CN116293868A

CN116293868A - Heat exchange system and control method thereof

Info

Publication number: CN116293868A
Application number: CN202310239531.5A
Authority: CN
Inventors: 袁占彪; 吕根贵; 钟文朝
Original assignee: Hisense Guangdong Air Conditioning Co Ltd
Current assignee: Hisense Guangdong Air Conditioning Co Ltd
Priority date: 2023-03-13
Filing date: 2023-03-13
Publication date: 2023-06-23

Abstract

The invention discloses a heat exchange system and a control method of the heat exchange system, wherein the heat exchange system comprises a heat pump, a first circulation branch, a second circulation branch, a two-way valve, a water mixing pump, a water mixing temperature sensing bulb and a controller, wherein a first heat exchange device is arranged on the first circulation branch; a second heat exchange device is arranged on the second circulation branch; the two-way valve is used for controlling the waterway circulation state in the second circulation branch; the water mixing valve and the water mixing pump are used for mixing the water outlet of the heat pump with the water outlet of the second circulation branch and conveying the mixed water into the second circulation branch; the water mixing temperature sensing bag is used for collecting the water mixing temperature; the controller is configured to: detecting that the heat pump is started and the heat exchange system operates in a heating mode, controlling the two-way valve to be started, and controlling the water mixing valve and the water mixing pump to be started; calculating a valve adjusting time ratio according to the target water mixing temperature and the water mixing temperature; and adjusting the opening of the water mixing valve according to the valve adjusting time ratio, and controlling the running state of the water mixing pump according to the opening of the water mixing valve.

Description

Heat exchange system and control method thereof

Technical Field

The invention relates to the technical field of thermal circulation, in particular to a heat exchange system and a control method of the heat exchange system.

Background

In the places needing heating in winter, europe is taken as an example, especially in families in northern europe and other areas, the sensitivity of stairs, kitchens and other places to thermal comfort is not strong, the heat dissipation mode of a radiator can be adopted to ensure that internal articles are not frosted, the bedroom needs more comfortable room temperature, and the floor heating is more suitable for the thermal comfort requirement of human bodies. However, the existing air source heat pump can only provide water with a temperature, and the required water supply temperature is 55-65 ℃ for the radiator, but if the water with the temperature is directly introduced into the floor, the wood floor can be raised and cracked, and even the floor is damaged.

In the prior art, when facing multiple terminal such as low temperature type ground heating, high temperature type radiator, fan disc, to intelligent water temperature carries out single control, and high temperature end and low temperature end heat supply open simultaneously the condition, when water temperature is too high, causes the timber apron to damage easily, when water temperature is too low, then high Wen Moduan's radiating effect can be variation, and these two kinds of setting methods can not satisfy human travelling comfort. In addition, in the actual heat pump operation process, the water temperature is changed continuously along with the change of the load of the compressor, and if the trend of the fluid temperature cannot be accurately judged only by the instantaneous temperature change.

Disclosure of Invention

The present invention aims to solve at least one of the technical problems existing in the prior art. To this end, a first object of the present invention is to propose a heat exchange system. The heat exchange system can realize the control of different water supply temperatures at different heating terminals, can achieve the aim of comfort and energy conservation, can improve the stability of the target water outlet temperature, and ensures that the adjusting process is more stable and reasonable.

A second object of the present invention is to provide a method for controlling a heat exchange system.

In order to achieve the above object, a heat exchange system according to an embodiment of a first aspect of the present invention includes: the heat pump is provided with a water inlet and a water outlet; the water inlet of the first circulation branch is connected with the water outlet of the heat pump, the water outlet of the first circulation branch is connected with the water inlet of the heat pump, and a first heat exchange device is arranged between the water inlet of the first circulation branch and the water outlet of the first circulation branch; the water inlet of the second circulation branch is connected with the water outlet of the heat pump, the first water outlet of the second circulation branch is connected with the water inlet of the heat pump, the second water outlet of the second circulation branch is connected with the water inlet of the second circulation branch and the water inlet of the heat pump, and a second heat exchange device is arranged between the water inlet of the second circulation branch and the first water outlet and between the water inlet of the second circulation branch and the second water outlet; the two-way valve is arranged at the water inlet of the second circulation branch and is used for controlling the waterway circulation state in the second circulation branch; the water mixing valve is arranged among the water inlet of the heat pump, the second water outlet of the second circulation branch and the water inlet of the second circulation branch and is used for mixing the water outlet of the heat pump with the water outlet of the second circulation branch; the water mixing pump is arranged at the water inlet of the second circulation branch and connected with the water mixing valve, and is used for conveying mixed water to the water inlet of the second circulation branch; the water mixing temperature sensing bulb is arranged at the water inlet of the second circulation branch and is used for collecting the temperature of mixed water; a controller configured to: detecting that the heat pump is started and the heat exchange system operates in a heating mode, controlling the two-way valve to be started, and controlling the water mixing valve and the water mixing pump to be started; calculating a valve adjusting time ratio according to a target water mixing temperature and the water mixing temperature; and adjusting the opening of the water mixing valve according to the valve adjusting time ratio, and controlling the running state of the water mixing pump according to the opening of the water mixing valve.

According to the heat exchange system provided by the embodiment of the invention, through the arrangement of the two-way valve, the heat supply for the first circulation branch circuit can be realized independently, and the heat supply for the first circulation branch circuit and the second circulation branch circuit can be realized simultaneously. Through setting up mixing water valve, mixing water pump and mixing water temperature sensing package, the aperture of mixing water valve and the running state of mixing water pump can be controlled according to mixing water temperature to the controller, and then under the assurance heating mode, mixing water valve and mixing water pump mutually support can be with the low temperature water mixing of the delivery port output of heat pump and the second delivery port department of second circulation branch road into the moderate mixed water of temperature, consequently can satisfy the terminal water supply demand of low temperature simultaneously with high temperature, compromise human travelling comfort again. And when the second heat exchange device is a floor heating coil, the temperature of mixed water is reasonably controlled, so that the problem that the wood floor is damaged after high-temperature water is directly connected to the floor heating coil can be solved. And the opening degree of the water mixing valve and the running state of the water mixing pump are circularly regulated according to the target water mixing temperature and the water mixing temperature, so that the stability of the target water outlet temperature can be improved, and the regulating process is more stable and more reasonable.

In some embodiments of the invention, in said calculating the valve-adjusting time ratio from the target water mixing temperature and the water mixing temperature, the controller is configured to: circularly acquiring the water mixing temperature at the last moment and the current water mixing temperature; calculating a first difference between the current water mixing temperature and the target water mixing temperature, and calculating a second difference between the last-time water mixing temperature and the current water mixing temperature; and determining a valve adjusting time ratio according to the first difference value and the second difference value.

In some embodiments of the present invention, in adjusting the opening of the mixing valve according to the valve adjustment time ratio, the controller is specifically configured to: calculating valve adjusting time according to the valve adjusting time ratio; determining that the valve adjusting time ratio is greater than zero, and controlling the water mixing valve to execute opening action in the valve opening direction on the basis of the current opening degree and continuously adjusting the valve duration; or determining that the valve adjusting time ratio is smaller than zero, and controlling the water mixing valve to execute closing action in the valve closing direction on the basis of the current opening degree and continuously adjusting the valve duration; or determining that the valve adjusting time is equal to zero, and controlling the water mixing valve to maintain the current opening.

In some embodiments of the invention, after said calculating the valve-timing length from said valve-timing time ratio, said controller is specifically further configured to: if the current opening of the water mixing valve is determined to be the maximum opening and the valve adjusting time ratio is greater than zero, controlling the water mixing valve to maintain the current opening; or if the current opening of the water mixing valve is determined to be the minimum opening and the valve adjusting time ratio is smaller than zero, controlling the water mixing valve to maintain the current opening.

In some embodiments of the present invention, in controlling the operation state of the water mixing pump according to the opening degree of the water mixing valve, the controller is specifically configured to: when the opening of the water mixing valve is determined to be the maximum opening or the minimum opening, the water mixing pump is controlled to be closed; or when the opening degree of the water mixing valve is determined to be larger than the minimum opening degree and smaller than the maximum opening degree, controlling the water mixing pump to be started.

In some embodiments of the invention, after said controlling the two-way valve to open, the controller is configured to: detecting the state of the water mixing temperature sensing bulb in response to the regional control effective signal; and controlling the heat pump, the water mixing valve and the water mixing pump according to the state of the water mixing temperature sensing bulb.

In some embodiments of the present invention, when the heat pump, the water mixing valve, and the water mixing pump are controlled according to the state of the water mixing bulb, the controller is specifically configured to: determining that the water mixing temperature sensing bulb is normal, controlling the water outlet temperature of the heat pump to be a first preset temperature, controlling the water mixing valve to be opened to a first preset opening degree, keeping a first preset duration, and controlling the water mixing pump to be opened; or determining that the water mixing temperature sensing bulb is abnormal, controlling the water outlet temperature of the heat pump to be the first preset temperature, controlling the water mixing valve to be opened to a second preset opening degree and kept, and controlling the water mixing pump to be opened, wherein the second preset opening degree is larger than the first preset opening degree.

In some embodiments of the invention, after said controlling the two-way valve to open, the controller is further configured to: and responding to a zone control invalidation signal, controlling the water mixing valve and the water mixing pump to be closed, and controlling the water outlet temperature of the heat pump to be a second preset temperature, wherein the second preset temperature is smaller than the first preset temperature.

Or determining that the heat exchange system exits the heating mode, and controlling the water mixing valve and the water mixing pump to be closed.

In some embodiments of the invention, after said controlling the mixing valve and the mixing pump to be on, the controller is further configured to: detecting a zone control invalidation signal and/or determining that the heat exchange system exits the heating mode; and controlling the water mixing valve and the water mixing pump to be closed.

In order to achieve the above object, an embodiment of a second aspect of the present invention provides a control method of a heat exchange system, for a heat exchange system as set forth in any one of the above, the control method including the steps of: detecting that the heat pump is started and the heat exchange system operates in a heating mode, controlling the two-way valve to be started, and controlling the water mixing valve and the water mixing pump to be started; calculating a regulating time ratio according to a target water mixing temperature and the water mixing temperature; and adjusting the opening of the water mixing valve according to the valve adjusting time ratio, and controlling the running state of the water mixing pump according to the opening of the water mixing valve.

According to the control method of the heat exchange system provided by the embodiment of the invention, when the heat exchange system operates in a heating mode, the two-way valve is controlled to be opened, so that heat supply for the first circulation branch and the second circulation branch can be realized at the same time. The opening degree of the water mixing valve and the running state of the water mixing pump are controlled according to the state of the water mixing temperature sensing bulb, so that the water mixing valve and the water mixing pump are mutually matched in a heating mode, high-temperature water output by the water outlet of the heat pump and low-temperature water at the second water outlet of the second circulation branch can be mixed into mixed water with moderate temperature, and therefore the water supply requirements of the high-temperature tail end and the low-temperature tail end can be met simultaneously, and the human comfort is also considered. And when the low-temperature tail end is a floor heating coil pipe, the problem that the wood floor is damaged after high-temperature water is directly connected to the floor heating coil pipe can be solved by reasonably controlling the temperature of mixed water. And the state of the water mixing valve and the water mixing pump is circularly regulated according to the target water mixing temperature and the water mixing temperature, so that the stability of the target water outlet temperature can be improved, and the regulating process is more stable and more reasonable.

Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention.

Drawings

The foregoing and/or additional aspects and advantages of the invention will become apparent and may be better understood from the following description of embodiments taken in conjunction with the accompanying drawings in which:

FIG. 1 is a block diagram of a heat exchange system according to one embodiment of the present invention;

FIG. 2 is a schematic diagram of a heat exchange system according to one embodiment of the present invention;

FIG. 3 is a block diagram of a heat exchange system according to another embodiment of the present invention;

FIG. 4 is a schematic illustration of a heat exchange system according to another embodiment of the present invention;

FIG. 5 is a flow chart of a method of controlling a heat exchange system according to one embodiment of the present invention;

fig. 6 is a flowchart of a control method of a heat exchange system according to another embodiment of the present invention.

Reference numerals:

a heat exchange system 10;

the heat pump 1, the first heat exchange device 2, the second heat exchange device 3, the two-way valve 4, the water mixing valve 51, the water mixing pump 52, the water mixing temperature sensing bulb 6, the controller 7, the water outlet temperature sensing bulb 8, the water return temperature sensing bulb 9 and the bypass valve A.

Detailed Description

Embodiments of the present invention will be described in detail below, by way of example with reference to the accompanying drawings.

The following description of the embodiments of the present invention will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present invention, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.

In the description of the present invention, it should be understood that the terms "center," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," and the like indicate orientations or positional relationships based on the orientation or positional relationships shown in the drawings, merely to facilitate describing the present invention and simplify the description, and do not indicate or imply that the devices or elements referred to must have a specific orientation, be configured and operated in a specific orientation, and thus should not be construed as limiting the present invention.

The terms "first," "second," and the like, are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include one or more such feature. In the description of the present invention, unless otherwise indicated, the meaning of "a plurality" is two or more.

In the description of the present invention, it should be noted that, unless explicitly specified and limited otherwise, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be either fixedly connected, detachably connected, or integrally connected, for example; can be mechanically or electrically connected; can be directly connected or indirectly connected through an intermediate medium, and can be communication between two elements. The specific meaning of the above terms in the present invention will be understood in specific cases by those of ordinary skill in the art.

The prior technical proposal discloses a control method for a water mixing valve of a water heater, which comprises the following steps: determining that the water mixing valve stops water outlet; acquiring a first water inlet temperature of a hot water inlet; acquiring a second water inlet temperature of the cold water inlet; acquiring the water retention temperature of water retained in the water mixing cavity when the water mixing valve stops water outlet; acquiring the change relation of the temperature of the reserved water along with time; determining the opening degree of a valve associated with the cold water inlet according to the change relation; the valve is adjusted to the determined opening. The application scene of the method is a water heater, and the purpose is to prevent high-temperature water from scalding people through water mixing and improve water use safety. However, the domestic air-water heat pump (air to water heat pump) can only realize single water supply temperature control, so that when the situation is met, namely, when the floor heating and the radiator are simultaneously heated, the single water supply temperature cannot be adapted, and further, the ideal comfort requirement cannot be met. In order to improve the stability of the target water outlet temperature and enable the adjustment process to be more stable and more reasonable, the heat exchange system provided by the embodiment of the invention can mix two streams of water supply and water return fluid into floor heating water supply with specific temperature according to the set temperature of a user, so that the water supply requirements of a high-temperature tail end and a low-temperature tail end can be met at the same time, the comfort of a human body is also considered, and the purpose of more accurate and stable control is achieved.

Based on the structure and function of the heat exchange system described above, the operation of the heat exchange system according to the embodiment of the present invention will be illustrated. A heat exchange system according to an embodiment of the present invention is described below with reference to fig. 1 to 4.

As shown in fig. 1, a block diagram of a heat exchange system according to an embodiment of the present invention is shown, wherein the heat exchange system 10 includes a heat pump 1, a first heat exchange device 2, a second heat exchange device 3, a two-way valve 4, a water mixing valve 51, a water mixing pump 52, a water mixing bulb 6, and a controller 7, wherein a first circulation branch and a second circulation branch are not shown in the figure.

In some embodiments, the heat pump 1 may be an air source heat pump host, which uses a small amount of electric energy to drive a compressor to operate, the high-pressure liquid working medium is evaporated into a gas state in an evaporator after passing through an expansion valve, and absorbs a large amount of heat energy from the air, the gas working medium is compressed into a high-temperature and high-pressure liquid state by the compressor, and then enters a condenser to release heat to heat water, and the water can be heated to 50-65 ℃ through cyclic heating. The heat pump 1 is provided with a water inlet and a water outlet, the water outlet outputs high-temperature water, the water inlet is used for refluxing circulating water in the whole system to the heat pump 1, and the arrow direction in fig. 1 indicates the flow direction of the circulating water in a pipeline.

The first circulation branch is used to form a circulation water path with the heat pump 1, and specifically, the heat exchange system 10 according to an embodiment of the present invention may be understood with reference to fig. 2, and fig. 2 is a schematic diagram of the heat exchange system according to an embodiment of the present invention. Wherein the first and second circulation branches are not shown in fig. 2.

The water inlet of the first circulation branch is connected with the water outlet of the heat pump 1, the water outlet of the first circulation branch is connected with the water inlet of the heat pump 1, and a first heat exchange device 2 is arranged between the water inlet of the first circulation branch and the water outlet of the first circulation branch. That is, the water output from the water outlet of the heat pump 1 enters the water inlet of the first circulation branch, passes through the water outlet of the first circulation branch and the water inlet of the heat pump 1 after passing through the first heat exchange device 2, and flows back to the heat pump.

Specifically, the first heat exchange device 2 may be a fan coil, and when circulating water flows through the fan coil, heat exchange is performed with air to convey cold air or hot air to a room, so as to realize a refrigeration or heating function. Alternatively, the first heat exchange device 2 may be a radiator, and the circulating water with high temperature flows through the radiator to exchange heat with air in the room, so as to achieve the purpose of heating the room.

The second circulation branch is used for forming another circulation waterway with the heat pump 1, the water inlet of the second circulation branch is connected with the water outlet of the heat pump 1, the first water outlet of the second circulation branch is connected with the water inlet of the heat pump 1, the second water outlet of the second circulation branch is connected with the water inlet of the second circulation branch and the water outlet of the heat pump 1, and a second heat exchange device 3 is arranged between the water inlet of the second circulation branch and the first water outlet and between the water inlet of the second circulation branch and the second water outlet.

That is, after the water in the second circulation branch flows through the second heat exchange device 3, a part of the water flows back to the heat pump through the first water outlet of the second circulation branch and the water inlet of the heat pump 1, and the other part of the water is mixed with the water output by the water outlet of the heat pump 1 at the second water outlet of the second circulation branch to form mixed water, and the mixed water continuously flows into the water inlet of the second circulation branch to participate in water circulation.

Specifically, the second heat exchange device 3 may be a floor heating coil, and when the high-temperature circulating water flows through the floor heating coil, the high-temperature water exchanges heat with the bottom plate and air in the room, so as to achieve the purpose of heating the room. Hereinafter, the first heat exchanger 2 is used as a radiator, and the second heat exchanger 3 is used as a floor heating coil.

It will be appreciated that for a radiator, the required water supply temperature is approximately 55-65 ℃, such high temperature water directly introduced into the floor will cause the wood floor to warp and crack, which is prone to damage to the floor, and when the floor is used to supply heat to a room, if the temperature of the floor heating coil is too high, the comfort of the human body will be affected, so that the water supply temperature of the floor heating coil can be generally set lower than that of the radiator or the fan coil. According to the heat exchange system provided by the embodiment of the invention, the second water outlet of the second circulation branch is connected with the water inlet of the second circulation branch and the water outlet of the heat pump 1, so that the low-temperature water flowing to the second water outlet of the second circulation branch through the second heat exchange device 3 can be mixed with the high-temperature water output by the water outlet of the heat pump 1, the temperature of the circulating water in the second circulation branch is lower than that of the circulating water in the first circulation branch, and different water temperature control is provided for the first circulation branch and the second circulation branch.

The two-way valve 4 is arranged at the water inlet of the second circulation branch, as shown in fig. 2, the two-way valve 4 can be arranged on a main pipe of the floor heating for controlling the water circulation state in the second circulation branch, when the two-way valve 4 is closed, the second circulation branch participates in the water circulation of the heat exchange system 10, and when the two-way valve 4 is closed, the heat exchange system 10 does not circulate water for the floor heating coil.

The water mixing valve 51 is arranged between the water inlet of the heat pump 1, the second water outlet of the second circulation branch and the water inlet of the second circulation branch, the valve body of the water mixing valve 51 is provided with three ports, two inlets and one outlet, and the two inlets are respectively connected with the water outlet of the heat pump 1 and the second water outlet of the second circulation branch and are used for mixing the water outlet of the heat pump 1 with the water outlet of the second circulation branch. The water mixing pump 52 is disposed at the water inlet of the second circulation branch and connected to the outlet of the water mixing valve 51 for delivering the mixed water to the water inlet of the second circulation branch. The combination of the water mixing valve 51 and the water mixing pump 52 can realize the function of mixing the floor heating backwater and the water outlet of the heat pump 1 in proportion to the water temperature required by the floor heating.

The water mixing temperature sensing bulb 6 is arranged at the water inlet of the second circulation branch and is used for collecting the temperature of the mixed water, and the water mixing temperature sensing bulb 2 can comprise a temperature sensor and the like detection device. Specifically, as shown in fig. 2, the mixed water temperature sensing bulb 6 may be disposed after the mixed water pump 52 for detecting the water temperature of the mixed ground heating branch.

The controller 7 may be a general controller in the whole heat exchange system 10, and may implement a control function for each part in the whole heat exchange system 10, and the controller 7 may further include a wire controller, which may be used to set the outlet water temperature of the heat pump 1 and set the system operation mode, and hereinafter, the control function of each part in the whole heat exchange system 10 will be mainly described by the controller 7.

As indicated by the broken lines in fig. 1, the controller 7 is connected to the heat pump 1, the two-way valve 4, the water mixing valve 51, the water mixing pump 52, and the water mixing bulb 6, respectively, and only the controller 7 is connected to the heat pump 1 shown in fig. 2.

The controller 7 is configured to: it is detected that the heat pump 1 is turned on and the heat exchange system 10 is operated in the heating mode, the two-way valve 4 is controlled to be turned on, and the water mixing valve 51 and the water mixing pump 52 are controlled to be turned on.

After the air source heat pump host is powered on and started, the operation mode of the heat exchange system 10 is judged. It will be appreciated that if the heat exchange system 10 is operated in the heating mode, the first heat exchange device 2 and the second heat exchange device 3 should both implement the heat supply function, and at this time, the second heat exchange device 3 needs to participate in the heat cycle, control the two-way valve 4 to open, and the waterway in the second circulation branch begins to circulate. And, in the heat exchange system 10 having the water mixing valve 51 and the water mixing pump 52, the water temperature of each circulation path is controlled, and after the water mixing valve 51 is controlled to be opened and the water mixing pump 52 is controlled to be opened, the heat exchange system 10 can control different water supply temperatures.

Alternatively, in some embodiments, when the heat pump 1 is detected to be on and the heat exchange system 10 is operating in the cooling mode, the two-way valve 4 is controlled to be closed. It will be appreciated that if the first heat exchange device 2 is a fan coil, the fan coil is used to deliver cool air to the room when the heat exchange system 10 is in the cooling mode, and the floor heating is not required to heat the room at this time, so that circulating water can be circulated through the floor heating coil without controlling the two-way valve 4 to be closed.

In some embodiments, the valve adjustment time ratio is calculated from the target water mixing temperature and the water mixing temperature.

The target water mixing temperature can be set in advance by a user or a worker and stored in the controller 7, and the target water mixing temperature should be the temperature of the circulating water in the second circulation branch when the second heat exchange device 4 supplies heat normally, and when the second heat exchange device 4 is a floor heating coil, the target water mixing temperature can meet the comfort requirement of a human body under the state of ensuring the installation property of the bottom plate.

It will be appreciated that, for the water mixing valve 51, a certain time is required for the process of adjusting it from closed to fully open and the process of adjusting it from fully open to closed, and the opening rate and the closing rate of the water mixing valve 51 are constant, so that the opening degree of the water mixing valve 51 can be controlled according to the operation time of the water mixing valve 51. Specifically, the time taken for the water mixing valve 51 to go from the closed state to the fully open state may be denoted by sv_mix_on, and the valve opening direction of the valve opening time sv_mix_on of the water mixing valve 51 may be defined as the direction in which the opening degree of the water mixing valve 51 increases, that is, the opening direction of the water mixing valve 51. And, the time taken for the water mixing valve 51 to go from the fully opened state to the closed state may be denoted by sv_mix_off, and the valve closing direction of the valve closing time sv_mix_off of the water mixing valve 51 may be defined as the direction in which the opening degree of the water mixing valve 51 decreases, that is, the water mixing valve 51 closing direction.

The valve opening period+closing period of the water mixing valve 51 is t_mix_onoff, t_mix_on+t_mix_off, wherein t_mix_onoff, t_mix_on and t_mix_off are settable parameters, such as 120 seconds, 60 seconds and 60 seconds, respectively, that is, the time taken for the water mixing valve 51 to be in the closed state to be in the fully opened state and from the fully opened state to be in the closed state is 60S. The opening time ratio of the mixing valve 51 is 100% of t_mix_on/t_mix_onoff; the valve closing time ratio of the water mixing valve 51 is-t_mix_on/t_mix_onoff 100%, and when the opening time ratio of the water mixing valve 51 is 50%, it means that the water mixing valve 51 is in the fully open state, and when the valve closing time ratio of the water mixing valve 51 is 50%, it means that the water mixing valve 51 is in the closed state.

Based on the above, it is known whether the valve adjustment time ratio of the water mixing valve 51 is actually calculated to be the degree of adjustment required or the degree of adjustment in the valve opening direction or the valve closing direction of the water mixing valve 51. Thus, the water mixing temperature can be obtained in a circulating manner, and further, after the water mixing temperature is obtained each time, the valve adjustment time ratio is calculated according to the water mixing temperature and the target water mixing temperature, and further, the adjustment direction of the opening degree of the water mixing valve 51 is determined.

In some embodiments, the opening degree of the water mixing valve 51 is adjusted according to the valve adjustment time ratio, and the operation state of the water mixing pump 52 is adjusted according to the opening degree of the water mixing valve 51.

For example, when the valve adjustment time ratio is positive, it may be set to indicate that the mixing valve 51 needs to be controlled to adjust in the valve opening direction at the current opening, and when the valve adjustment time ratio is negative, it may be set to indicate that the mixing valve 51 needs to be controlled to adjust in the valve closing direction at the current opening.

And, it can be understood that the water mixing valve 51 needs to be controlled to be opened first by the action of mixing water, and the water mixing pump 52 needs to pump water, and the two conditions are in a same relationship, and the water mixing function can only be realized if all the two conditions are reached, and the water mixing effect can not be generated by either one alone. If the water mixing valve 51 is in a closed state, the water mixing pump 52 is operated to cause no water operation, and the water mixing pump 52 is easily damaged; if the water mixing valve 51 is in an open state, the water mixing pump 52 is not turned on, water does not flow, and a water mixing effect cannot be produced. Thus, when the water mixing valve 51 is controlled to be opened, the water mixing pump 52 is controlled to be opened, and when the water mixing valve 51 is closed, the water mixing pump 52 is controlled to be closed. Or when the water mixing valve 51 is determined to be in the full-open state, no obstruction exists in the pipeline, and the expected water mixing effect can be achieved without opening the water mixing pump 52, so that the water mixing pump 52 is controlled to be closed under the full-open state of the water mixing valve 51.

Through adjusting the aperture of the water mixing valve 51 and the running state of the water mixing pump 52, the water mixing temperature in the second circulation branch can be dynamically adjusted, and then the temperature of the mixed water is reasonably controlled, so that the second circulation branch can always provide proper heat for the space in a heating mode. In addition, the opening degree of the water mixing valve 51 and the running state of the water mixing pump 52 are circularly regulated according to the target water mixing temperature and the water mixing temperature, so that the stability of the target water outlet temperature can be improved, and the regulating process is more stable and reasonable.

According to the heat exchange system 10 provided by the embodiment of the invention, by arranging the two-way valve 4, the heat supply of the first circulation branch can be realized independently, and the heat supply of the first circulation branch and the second circulation branch can be realized simultaneously. Through setting up mixing valve 51, mixing pump 52 and mixing thermal bulb 6, the aperture of mixing valve 51 and the running state of mixing pump 52 can be controlled according to the mixed water temperature to the controller, and then under the assurance heating mode, mixing valve 51 and mixing pump 52 mutually support can be with the low temperature water mixing of the delivery port output of heat pump 1 and the second delivery port department of second circulation branch into the moderate mixed water of temperature, consequently can satisfy the terminal water supply demand of low temperature simultaneously with high temperature, compromise human travelling comfort again. And when the second heat exchange device 4 is a floor heating coil, the temperature of mixed water is reasonably controlled, so that the problem that the wood floor is damaged after high-temperature water is directly connected to the floor heating coil can be solved. And, by adjusting the opening of the water mixing valve 51 and the operation state of the water mixing pump 52 according to the target water mixing temperature and the water mixing temperature cycle, the stability of the target water outlet temperature can be improved, and the adjustment process can be made more stable and more reasonable.

In some embodiments of the present invention, when calculating the valve-adjusting time ratio from the target water mixing temperature and the water mixing temperature, the controller 7 is specifically configured to: and circularly acquiring the water mixing temperature at the last moment and the current water mixing temperature. And further calculating a first difference between the current water mixing temperature and the target water mixing temperature, and calculating a second difference between the water mixing temperature at the previous time and the current water mixing temperature.

Specifically, after the first control of the water mixing valve 51 to be opened to the first preset opening and the holding time to reach the first preset duration, the water mixing temperature at the previous time and the current water mixing temperature are circularly obtained. The detected water mixing temperature at the previous moment is recorded as T (n-1), and after a period of time, the current water mixing temperature is detected again and is then T (n), wherein the time interval for obtaining the water mixing temperature twice can be set to be 1min, namely the previous 1min at the current moment at the previous moment.

Further, the time interval for circularly acquiring the water mixing temperature at the previous time and the current water mixing temperature, that is, the time interval for acquiring the T (n-1) and the T (n) at the previous time and acquiring the T (n-1) and the T (n) at the next time, can be set to be 60s. Wherein the first difference is denoted as Δt1 and the second difference is denoted as Δt2, wherein Δt1=t (n) -T0, and Δt2=t (n) -T (n-1).

In some embodiments, the valve adjustment time ratio is determined from the first difference and the second difference.

Specifically, the relationship between the first difference, the second difference, and the valve timing ratio of the embodiment of the present invention can be understood from table 1.

TABLE 1

For example, as shown in table 1, when Δt1=4, Δt2= -1, the valve timing ratio is-5%; for another example, when Δt1= -3, Δt2=2, the valve timing ratio is 1%; for another example, when Δt1=0, Δt2=2, the valve timing ratio is-3%.

In some embodiments, in adjusting the opening of the mixing valve 51 according to the valve adjustment time ratio, the controller 7 is specifically configured to: and calculating the valve adjusting time according to the valve adjusting time ratio. The valve-adjusting time ratio is determined to be larger than zero, and the water mixing valve 51 is controlled to perform an opening action in the valve-opening direction on the basis of the current opening degree and to continue the valve-adjusting time period. Or, the valve adjusting time ratio is determined to be smaller than zero, and the water mixing valve 51 is controlled to perform closing action in the valve closing direction on the basis of the current opening and continuously adjust the valve adjusting time. Alternatively, the valve adjustment time is determined to be equal to zero, and the mixing valve 51 is controlled to maintain the current opening.

For example, when the valve-adjusting time ratio is 15%, the valve-adjusting time length is t_mix_onoff 15%, taking default t_mix_onoff=120s as an example, the valve-adjusting time length is 18S, when the valve-adjusting time ratio is-3%, the valve-adjusting time length is t_mix_onoff 3%, the valve-adjusting time length is 3.6S, when the valve-adjusting time ratio is 0%, the valve-adjusting time length is t_mix_onoff 0%, and the valve-adjusting time length is 0S.

Taking the valve adjusting time ratio of 15% as an example, that is, controlling the water mixing valve 51 to continuously perform the opening operation in the valve opening direction for 18S on the basis of the current opening degree; taking the valve adjusting time ratio of-3% as an example, that is, controlling the water mixing valve 51 to continuously execute the valve closing action in the valve closing direction for 3.6S on the basis of the current opening; taking the valve adjustment time ratio of 0% as an example, the mixing valve 51 is controlled to maintain the current opening degree unchanged until the next operation of adjusting the opening degree of the mixing valve 51 is performed.

Further, according to the heat exchange system 10 according to the embodiment of the present invention, after calculating the valve adjusting time period according to the valve adjusting time ratio, the controller 7 is specifically further configured to: if it is determined that the current opening of the water mixing valve 51 is the maximum opening and the valve adjustment time ratio is greater than zero, that is, if the calculated valve adjustment time ratio is greater than zero, but the water mixing valve 51 is already in the fully open state, at this time, the water mixing valve 51 cannot be further controlled to perform the opening operation, and the water mixing valve 51 is controlled to maintain the current opening. Alternatively, if it is determined that the current opening of the water mixing valve 51 is the minimum opening and the valve adjustment time ratio is smaller than zero, that is, if the calculated valve adjustment time ratio is smaller than zero, but the water mixing valve 51 is already in the closed state, at this time, the water mixing valve 51 cannot be further controlled to perform the closing operation, and the water mixing valve 51 is controlled to maintain the current opening.

Or if the valve adjusting time ratio is determined to be greater than zero, and the continuous opening time of the water mixing valve 51 is controlled to not reach the valve adjusting time in the process of controlling the water mixing valve 51 to execute the opening action, and the water mixing valve 51 is controlled to keep the maximum opening degree when the water mixing valve 51 reaches the maximum opening degree; or if the valve adjusting time ratio is determined to be smaller than zero, and the continuous closing time of the water mixing valve 51 is not up to the valve adjusting time in the process of controlling the water mixing valve 51 to execute the closing action, the water mixing valve 51 is controlled to be kept in the closing state after the water mixing valve 51 is closed.

In some embodiments, in controlling the operation state of the water mixing pump 52 according to the opening degree of the water mixing valve 51, the controller 7 is specifically configured to: when the opening of the water mixing valve 51 is determined to be the maximum opening or the minimum opening, the water mixing pump 52 is controlled to be turned off. Alternatively, when it is determined that the opening of the water mixing valve 51 is greater than the minimum opening and less than the maximum opening, the water mixing pump 52 is controlled to be turned on.

It is understood that the water mixing valve 51 is open and the water mixing pump 52 is on, whereby when it is determined that the opening time ratio of the water mixing valve 51 is 0%, the water mixing pump 52 is synchronously controlled to be off when the water mixing valve 51 is in the closed state. When the opening time ratio of 0% < the water mixing valve 51 is < 50%, it means that the water mixing valve 52 is in a partially opened state, and the water mixing valve 52 is controlled to be opened. And when the opening time ratio of the water mixing valve 51 is 50%, it means that the water mixing valve 51 is in a fully opened state, at this time, the water mixing valve 51 will not generate resistance to the water in the pipeline, and even if the water mixing pump 52 is not pumping water, the water from the water outlet of the heat pump 1 and the water from the second water outlet of the second circulation branch can automatically flow to the water inlet of the second circulation branch after being mixed, so that the water mixing pump 52 can be controlled to be closed when the water mixing valve 52 is in a fully opened state.

Further, when the water mixing pump 52 is turned from off to on, the water mixing requirement is illustrated, and considering that the change of the water temperature has hysteresis, the water temperature needs to wait for 1min, so that the condition that the water temperature is regulated to fluctuate and cannot be regulated is avoided; the mixing pump 52 is turned from on to off, indicating that the water temperature has fallen below a preset value, at which time if waiting continues, user comfort is affected, so it is desirable to turn off immediately.

Based on the above, by circularly adjusting the opening of the water mixing valve 51 according to the target water mixing temperature and the water mixing temperature and adjusting the operation state of the water mixing pump 52 according to the opening of the water mixing valve 51, the stability of the target water outlet temperature can be improved, and the adjustment process is more stable and reasonable.

In some embodiments, after controlling the two-way valve 4 to open, the controller 7 is further configured to: in response to the zonal control effective signal, the state of the water mixing temperature sensing bulb 6 is detected. The flag for determining whether or not the partition control valid signal is present may be a mixed water bulb 6. If the mixed water temperature sensing bulb 6 is detected, the heat exchange system 10 has the function of controlling the water temperature of each circulation branch, and the state of the mixed water temperature sensing bulb 6 needs to be further detected, if the mixed water temperature sensing bulb 6 is not detected, the heat exchange system 10 can only perform single water temperature control, and different water supply temperature control cannot be realized.

Further, in some embodiments, the heat pump 1, the water mixing valve 51, and the water mixing pump 52 are controlled according to the state of the water mixing bulb 6.

For example, when it is determined that the detected mixed water bulb 6 is normal, it means that the mixed water temperature can be monitored and adjusted later, that is, the heat exchange system 10 of the present invention can control the water temperature of each circulation branch separately. At this time, the water outlet temperature of the heat pump 1 can be controlled to be relatively high, and the water mixing valve 51 can be controlled to be opened and the water mixing pump 52 can be controlled to be opened, and at this time, the water mixing valve 51 has a function of dynamically adjusting the temperature of the mixed water. Or, when it is determined that the mixed water temperature sensing bulb 6 is abnormal, it is indicated that the heat exchange system 10 has a function of controlling the water temperature of each circulation branch, but monitoring and adjusting the mixed water temperature cannot be realized later. At this time, the outlet water temperature of the heat pump 1 can be controlled to be relatively low, and the water mixing valve 51 can be controlled to be opened and the water mixing pump 52 can be controlled to be opened, but at this time, the water mixing valve 51 does not have a function of dynamically adjusting the temperature of the mixed water.

In controlling the heat pump 1, the water mixing valve 51, and the water mixing pump 52 according to the state of the water mixing bulb 6, the controller 7 is specifically configured to: the water mixing temperature sensing bulb 6 is determined to be normal, the water outlet temperature of the heat pump 1 is controlled to be a first preset temperature, the water mixing valve 51 is controlled to be opened to a first preset opening degree and kept for a first preset duration, and the water mixing pump 52 is controlled to be opened.

It will be appreciated that when it is determined that the sensed water mixing bulb 6 is normal, this means that the temperature of the mixed water can be monitored and adjusted later, that is, the heat exchange system 10 of the present invention can control the water temperature of each circulation branch separately. At this time, the water outlet temperature of the heat pump 1 can be controlled to be relatively high, and the water mixing valve 51 and the water mixing pump 52 can be controlled to be opened, and at this time, the water mixing valve 51 has a function of dynamically adjusting the temperature of the mixed water.

As is clear from the above, the temperature of the circulating water in the second circulation path is lower than that in the first circulation path, and thus it is necessary to control the water mixing valve 51 to be opened and the water mixing pump 52 to be opened. At this time, the outlet water temperature of the heat pump 1 is approximately equal to the temperature of the circulating water in the first circulation branch, so the first preset temperature may be set according to the water temperature requirement in the first circulation branch or according to the operation requirement of the first heat exchanger 2, for example, when the first heat exchanger 2 is a radiator, the first preset temperature may be set to 55 ℃, 60 ℃, 65 ℃ or the like, which is not limited herein. And, when the water mixing valve 51 is controlled to be opened for the first time, since there is no reference data, the opening degree of the water mixing valve 51 cannot be determined directly according to the reference information, and therefore, an initial opening degree, that is, a first preset opening degree, needs to be preset, and each time the heat pump 1 is powered on and the water mixing valve 51 is opened for the first time, the opening degree of the water mixing valve 51 is adjusted to the first preset opening degree, and the water mixing pump 52 is controlled to be opened.

For example, the initial state of the water mixing valve 51 is closed, after the heat pump 1 is powered on and started, the water mixing valve 51 performs a valve opening operation, and the initial opening time ratio may be preset to be +25%, that is, the valve opening operation time is 30S, at this time, the opening of the water mixing valve 51 is adjusted to a first preset opening, and the first preset opening is half of the full opening state.

Further, considering that the operation state of the heat exchange system 10 is not stable when the first control of the water mixing valve 51 is opened, the power of the compressor in the heat pump 1 does not reach the predetermined operation state yet, so that the water mixing valve 51 needs to be kept for a certain period of time after being opened to the first preset opening degree, and the adjustment operation of the water mixing valve 51 is executed after the system operation is stable. The first preset time period may be set as required, for example, the first preset time period may be set to 8min or 9min or 10min or 11min, etc., which is not limited herein specifically. Preferably, the first preset time period may be set to 10 minutes.

Or, determining that the water mixing temperature sensing bulb 6 is abnormal, controlling the water outlet temperature of the heat pump 1 to be a first preset temperature, controlling the water mixing valve 51 to be opened to a second preset opening degree and keeping the water mixing valve, and controlling the water mixing pump 52 to be opened, wherein the second preset opening degree is larger than the first preset opening degree.

When it is determined that the mixed water temperature sensing bulb 6 is abnormal, it is indicated that the heat exchange system 10 has a function of controlling the water temperature of each circulation branch, but monitoring and adjusting the mixed water temperature may not be realized later. At this time, the outlet water temperature of the heat pump 1 can be controlled to be relatively low, and the water mixing valve 51 can be controlled to be opened and the water mixing pump 52 can be controlled to be opened, but at this time, the water mixing valve 51 does not have a function of dynamically adjusting the temperature of the mixed water.

And as can be seen from the above, the temperature of the circulating water in the second circulation branch should be lower than that of the circulating water in the first circulation branch, so that the opening of the water mixing valve 51 should be controlled to be kept at a certain opening, wherein the second preset opening is not too large or too small, so that the purpose of supplying heat to two circulation branches and basically ensuring that the temperature of the circulating water in the second circulation branch is lower than that of the circulating water in the first circulation branch can be achieved.

The second preset opening degree may be set as required, that is, the opening time ratio of the water mixing valve 51 may be set as required under the current working condition, for example, the opening time ratio may be set to +35%, that is, the valve opening action time is 42S, and the water mixing valve 51 is controlled to maintain the current opening degree, and the water mixing pump 52 is controlled to be opened.

In other embodiments, after controlling the two-way valve 4 to open, the controller 7 is further configured to: in response to the zone control invalidation signal, the water mixing valve 51 and the water mixing pump 52 are controlled to be closed, and the water outlet temperature of the heat pump 1 is controlled to be a second preset temperature, wherein the second preset temperature is smaller than the first preset temperature.

From the above, when the partition control invalidation signal is received, it indicates that the system does not detect the mixed water bulb 6, and the heat exchange system 10 can only perform single water temperature control, that is, the temperature of the circulating water in the second circulation branch is the same as the temperature of the circulating water in the first circulation branch, and different water supply temperature control cannot be achieved. Because the temperature of the circulating water in the second circulation branch is lower than that of the circulating water in the first circulation branch, the water temperature cannot be too high when the fan coil or the radiator heats with the floor heating, and the single water temperature control can be realized by controlling the water outlet temperature of the heat pump 1. The second preset temperature may be set as needed, and preferably, the second preset temperature may be set to be less than 40 ℃, for example, the first preset temperature may be set to 35 ℃, 38 ℃, 40 ℃, or the like, which is not limited herein. By limiting the set temperature of the outlet water of the heat pump 1 below 40 ℃, the use safety of the second heat exchange device 3 can be ensured on the basis of basically meeting the heat supply requirement. At this time, the water mixing valve 52 is not needed, and the water mixing valve 51 can be controlled to be closed and the water mixing pump 52 can be controlled to be closed.

In some embodiments, after controlling the mixing valve 51 and the mixing pump 52 to open, the controller 7 is further configured to: the zone control disable signal is detected and/or it is determined that the heat exchange system 10 is exiting the heating mode, and the mixing valve 51 and mixing pump 52 are controlled to close.

Wherein, in the process of circularly adjusting the water temperature in the second circulation branch, when the partition control invalidation signal is detected and/or the heat exchange system 10 exits from the heating mode, the second circulation branch does not need to participate in the water circulation in the system, at this time, different water temperature control is not needed to be provided for the first circulation branch and the second circulation branch, and the water mixing valve 51 and the water mixing pump 52 are controlled to be closed.

Furthermore, in some embodiments of the present invention, FIG. 3 is a block diagram of a heat exchange system according to another embodiment of the present invention; fig. 4 is a schematic view of a heat exchange system according to another embodiment of the present invention. The heat exchange system 10 of an embodiment of the present invention can be further understood in conjunction with fig. 3 and 4, wherein only the controller 7 is shown in fig. 4 in connection with the heat pump 1.

As shown in fig. 3 and 4, the heat exchange system 10 further includes a water outlet thermal bulb 8 and a water return thermal bulb 9, wherein the water outlet thermal bulb 8 is disposed at the water outlet of the heat pump 1, and is used for collecting the water outlet temperature of the heat pump 1. The backwater temperature sensing bag 9 is arranged at the second water outlet of the second circulation branch and is used for collecting backwater temperature at the second water outlet. The outlet water temperature sensing bulb 8 and the return water temperature sensing bulb 9 may include temperature sensor isothermal detection means. And the heat exchange system of the embodiment of the invention further comprises a bypass valve A, wherein the bypass valve A is arranged between the water outlet pipe and the water inlet pipe of the heat pump 1, and when the waterways in the first circulation branch and the second circulation branch are not communicated, the bypass valve A can conduct the water flow in the circulation loop to prevent the waterways from being protected.

In some embodiments of the present invention, a control method of a heat exchange system is also provided, for the heat exchange system 10 according to any one of the above embodiments, as shown in fig. 5, which is a flowchart of a control method of a heat exchange system according to one embodiment of the present invention, where the method includes the following steps S1-S4, specifically as follows.

S1, detecting that the heat pump is started and the heat exchange system operates in a heating mode, controlling the two-way valve to be started, and controlling the water mixing valve and the water mixing pump to be started.

After the air source heat pump host is powered on and started, if the heat exchange system operates in a heating mode, the first heat exchange device and the second heat exchange device are both required to realize a heat supply function, at the moment, the second heat exchange device needs to participate in heat circulation, the two-way valve is controlled to be opened, and a waterway in the second circulation branch circuit starts to circulate. And for the heat exchange system with the water mixing valve and the water mixing pump, the heat exchange system has the function of respectively controlling the water temperature of each circulation branch, and can control different water supply temperatures after controlling the water mixing valve to be opened and controlling the water mixing pump to be opened.

S2, calculating a valve adjusting time ratio according to the target water mixing temperature and the water mixing temperature.

The target water mixing temperature can be set in advance by a user or a worker and stored in the controller, the target water mixing temperature is the temperature of circulating water in the second circulating branch when the second heat exchange device supplies heat normally, and when the second heat exchange device is a floor heating coil, the target water mixing temperature can meet the comfort requirement of a human body under the condition of ensuring the installation property of the bottom plate.

The water mixing valve needs a certain time in the process of adjusting the water mixing valve from the closed state to the fully opened state and in the process of adjusting the water mixing valve from the fully opened state to the closed state, and the opening rate and the closing rate of the water mixing valve are certain, so that the opening degree of the water mixing valve can be controlled according to the action time of the water mixing valve. The valve adjusting time ratio of the water mixing valve is calculated, and the degree of the water mixing valve which is to be adjusted in the valve opening direction or the valve closing direction and is required to be adjusted is calculated. Therefore, the mixed water temperature can be circularly obtained, and the valve adjusting time ratio is calculated according to the mixed water temperature and the target mixed water temperature after the mixed water temperature is obtained each time, so that the adjustment direction of the opening of the mixed water valve is judged.

And S3, adjusting the opening of the water mixing valve according to the valve adjusting time ratio, and adjusting the running state of the water mixing pump according to the opening of the water mixing valve.

For example, when the valve adjustment time ratio is positive, it indicates that the mixing valve needs to be controlled to adjust in the valve opening direction at the current opening, and when the valve adjustment time ratio is negative, it indicates that the mixing valve needs to be controlled to adjust in the valve closing direction at the current opening.

And it can be understood that the action of mixing water needs to control the water mixing valve to be opened firstly, and the water mixing pump is required to pump water, and the two conditions are in a combined relation, so that the water mixing function can be realized only if all the two conditions are reached, and the effect of mixing water cannot be generated by any one of the two conditions alone. If the water mixing valve is in a closed state, the water mixing pump runs to cause no water running, so that the water mixing pump is easy to damage; if the water mixing valve is in an open state, the water mixing pump is not started, so that water cannot flow, and the water mixing effect cannot be generated. Therefore, after the water mixing valve is controlled to be opened, the water mixing pump is controlled to be opened, and when the water mixing valve is closed, the water mixing pump is controlled to be closed. Or when the water mixing valve is determined to be in the full-open state, no obstruction exists in the pipeline, the expected water mixing effect can be achieved without opening the water mixing pump, and the water mixing pump is controlled to be closed under the full-open state of the water mixing valve.

Through adjusting the aperture of mixing valve and the running state of mixing pump, can the dynamic adjustment second circulate the mixed water temperature in the branch road, and then the temperature of rational control mixed water for the second circulate the branch road under the heating mode, can provide suitable heat for the space all the time. In addition, the opening degree of the water mixing valve 51 and the running state of the water mixing pump 52 are circularly regulated according to the target water mixing temperature and the water mixing temperature, so that the stability of the target water outlet temperature can be improved, and the regulating process is more stable and reasonable.

According to the control method of the heat exchange system provided by the embodiment of the invention, when the heat exchange system operates in a heating mode, the two-way valve is controlled to be opened, so that heat supply for the first circulation branch and the second circulation branch can be realized at the same time. The opening degree of the water mixing valve and the running state of the water mixing pump are controlled according to the state of the water mixing temperature sensing bulb, so that the water mixing valve and the water mixing pump are mutually matched in a heating mode, high-temperature water output by the water outlet of the heat pump and low-temperature water at the second water outlet of the second circulation branch can be mixed into mixed water with moderate temperature, and therefore the water supply requirements of the high-temperature tail end and the low-temperature tail end can be met simultaneously, and the human comfort is also considered. And when the low-temperature tail end is a floor heating coil pipe, the problem that the wood floor is damaged after high-temperature water is directly connected to the floor heating coil pipe can be solved by reasonably controlling the temperature of mixed water. And, by adjusting the opening of the water mixing valve 51 and the operation state of the water mixing pump 52 according to the target water mixing temperature and the water mixing temperature cycle, the stability of the target water outlet temperature can be improved, and the adjustment process can be made more stable and more reasonable.

In some embodiments of the present invention, as shown in fig. 6, a flowchart of a control method of a heat exchange system according to another embodiment of the present invention is shown, wherein the control method includes the following steps S101-S113, specifically as follows.

And S101, after the heat pump is started to operate, judging whether the system operates in a heating mode, if the judging result is yes, executing the step S102, and if the judging result is no, executing the step S103, and closing a ground heating waterway two-way valve, wherein the ground heating waterway is recorded as a second circulation branch in the above.

S102, opening a ground heating waterway two-way valve.

S104, judging whether a water mixing temperature sensing bulb exists, if yes, executing step S105, and if no, executing step S106, and controlling the water mixing valve opening time ratio to be +35% and the water mixing pump to be opened.

S105, judging whether the water mixing temperature sensing bag is in fault, if the judging result is yes, executing step S107, controlling the opening degree of the water mixing valve to be fixed by 35%, and if the judging result is no, executing step S108.

S108, setting a target water mixing temperature T0.

S109, detecting the water mixing temperature T (n-1) at the previous moment and the water mixing temperature T (n) at the current moment,

s110, calculating a difference value delta T1 between the water mixing temperature and the target water mixing temperature, and calculating a difference value delta T2 between the water mixing temperature and the current water mixing temperature at the previous moment.

S111, adjusting the opening of the water mixing valve according to the DeltaT 1 and DeltaT 2, wherein the specific adjustment mode can be understood by combining the above description, and details are not repeated here.

S112, it is determined whether the current opening time of the water mixing valve has reached 60S, and if yes, the process returns to step S1099, and if no, the process proceeds to step S113.

S113, maintaining the current opening degree.

In the description of the present specification, reference to the terms "one embodiment," "some embodiments," "illustrative embodiments," "examples," "specific examples," or "some examples," etc., means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiments or examples.

While embodiments of the present invention have been shown and described, it will be understood by those of ordinary skill in the art that: many changes, modifications, substitutions and variations may be made to the embodiments without departing from the spirit and principles of the invention, the scope of which is defined by the claims and their equivalents.

Claims

1. A heat exchange system, comprising:

the heat pump is provided with a water inlet and a water outlet;

the water inlet of the first circulation branch is connected with the water outlet of the heat pump, the water outlet of the first circulation branch is connected with the water inlet of the heat pump, and a first heat exchange device is arranged between the water inlet of the first circulation branch and the water outlet of the first circulation branch;

the water inlet of the second circulation branch is connected with the water outlet of the heat pump, the first water outlet of the second circulation branch is connected with the water inlet of the heat pump, the second water outlet of the second circulation branch is connected with the water inlet of the second circulation branch and the water inlet of the heat pump, and a second heat exchange device is arranged between the water inlet of the second circulation branch and the first water outlet and between the water inlet of the second circulation branch and the second water outlet;

the two-way valve is arranged at the water inlet of the second circulation branch and is used for controlling the waterway circulation state in the second circulation branch;

the water mixing valve is arranged among the water inlet of the heat pump, the second water outlet of the second circulation branch and the water inlet of the second circulation branch and is used for mixing the water outlet of the heat pump with the water outlet of the second circulation branch;

The water mixing pump is arranged at the water inlet of the second circulation branch and connected with the water mixing valve, and is used for conveying mixed water to the water inlet of the second circulation branch;

the water mixing temperature sensing bulb is arranged at the water inlet of the second circulation branch and is used for collecting the temperature of mixed water;

a controller configured to:

detecting that the heat pump is started and the heat exchange system operates in a heating mode, controlling the two-way valve to be started, and controlling the water mixing valve and the water mixing pump to be started;

calculating a valve adjusting time ratio according to a target water mixing temperature and the water mixing temperature;

and adjusting the opening of the water mixing valve according to the valve adjusting time ratio, and controlling the running state of the water mixing pump according to the opening of the water mixing valve.

2. The heat exchange system according to claim 1, wherein, in calculating the valve-adjusting time ratio from the target water mixing temperature and the water mixing temperature, the controller is specifically configured to:

circularly acquiring the water mixing temperature at the last moment and the current water mixing temperature;

calculating a first difference between the current water mixing temperature and the target water mixing temperature, and calculating a second difference between the last-time water mixing temperature and the current water mixing temperature;

And determining a valve adjusting time ratio according to the first difference value and the second difference value.

3. The heat exchange system according to claim 2, wherein, in said adjusting the opening of the water mixing valve according to the valve adjustment time ratio, the controller is specifically configured to:

calculating valve adjusting time according to the valve adjusting time ratio;

determining that the valve adjusting time ratio is greater than zero, and controlling the water mixing valve to execute opening action in the valve opening direction on the basis of the current opening degree and continuously adjusting the valve duration;

or determining that the valve adjusting time ratio is smaller than zero, and controlling the water mixing valve to execute closing action in the valve closing direction on the basis of the current opening degree and continuously adjusting the valve duration;

or determining that the valve adjusting time is equal to zero, and controlling the water mixing valve to maintain the current opening.

4. A heat exchange system according to claim 3, wherein after said calculating a valve-timing duration from said valve-timing ratio, said controller is specifically further configured to:

if the current opening of the water mixing valve is determined to be the maximum opening and the valve adjusting time ratio is greater than zero, controlling the water mixing valve to maintain the current opening;

or if the current opening of the water mixing valve is determined to be the minimum opening and the valve adjusting time ratio is smaller than zero, controlling the water mixing valve to maintain the current opening.

5. The heat exchange system according to claim 4, wherein, in controlling the operation state of the water mixing pump according to the opening degree of the water mixing valve, the controller is specifically configured to:

when the opening of the water mixing valve is determined to be the maximum opening or the minimum opening, the water mixing pump is controlled to be closed;

or when the opening degree of the water mixing valve is determined to be larger than the minimum opening degree and smaller than the maximum opening degree, controlling the water mixing pump to be started.

6. The heat exchange system according to claim 2, wherein after the controlling the two-way valve to open, the controller is configured to:

detecting the state of the water mixing temperature sensing bulb in response to the regional control effective signal;

and controlling the heat pump, the water mixing valve and the water mixing pump according to the state of the water mixing temperature sensing bulb.

7. The heat exchange system according to claim 6, wherein, in controlling the heat pump, the water mixing valve, and the water mixing pump according to the state of the water mixing bulb, the controller is specifically configured to:

determining that the water mixing temperature sensing bulb is normal, controlling the water outlet temperature of the heat pump to be a first preset temperature, controlling the water mixing valve to be opened to a first preset opening degree, keeping a first preset duration, and controlling the water mixing pump to be opened;

Or determining that the water mixing temperature sensing bulb is abnormal, controlling the water outlet temperature of the heat pump to be the first preset temperature, controlling the water mixing valve to be opened to a second preset opening degree and kept, and controlling the water mixing pump to be opened, wherein the second preset opening degree is larger than the first preset opening degree.

8. The heat exchange system of claim 7, wherein after the controlling the two-way valve to open, the controller is further configured to:

and responding to a zone control invalidation signal, controlling the water mixing valve and the water mixing pump to be closed, and controlling the water outlet temperature of the heat pump to be a second preset temperature, wherein the second preset temperature is smaller than the first preset temperature.

9. The heat exchange system of claim 1, wherein after said controlling the water mixing valve and the water mixing pump to open, the controller is further configured to:

detecting a zone control invalidation signal and/or determining that the heat exchange system exits the heating mode;

and controlling the water mixing valve and the water mixing pump to be closed.

10. A control method for a heat exchange system according to any one of claims 1-9, comprising the steps of:

Determining that the heat exchange system operates in a heating mode, controlling the heat pump and the two-way valve to be opened, and controlling the water mixing valve and the water mixing pump to be opened;

calculating a regulating time ratio according to a target water mixing temperature and the water mixing temperature;