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CN103808012A - variable-frequency water heater and control method thereof - Google Patents

variable-frequency water heater and control method thereof Download PDF

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Publication number
CN103808012A
CN103808012A CN201210452507.1A CN201210452507A CN103808012A CN 103808012 A CN103808012 A CN 103808012A CN 201210452507 A CN201210452507 A CN 201210452507A CN 103808012 A CN103808012 A CN 103808012A
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Prior art keywords
pressure
compressor
time
frequency
water heater
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CN201210452507.1A
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CN103808012B (en
Inventor
黄娟
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Gree Electric Appliances Inc of Zhuhai
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Gree Electric Appliances Inc of Zhuhai
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Priority to CN201210452507.1A priority Critical patent/CN103808012B/en
Publication of CN103808012A publication Critical patent/CN103808012A/en
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Abstract

The invention provides a variable-frequency water heater and a control method thereof. This frequency conversion water heater includes compressor, cross valve, evaporimeter, water fluorine heat exchanger or condenser and controller, and compressor, cross valve, evaporimeter, water fluorine heat exchanger or condenser connect gradually and form the refrigeration circuit, the frequency conversion water heater still includes pressure measurement device, pressure measurement device sets up the blast pipe department of compressor is used for detecting the exhaust pressure of compressor, pressure measurement device with the controller electricity is connected, the controller is in when pressure measurement device detects the exhaust pressure of compressor and reaches preset pressure, control reduces the frequency or the shutdown protection of compressor. The variable frequency water heater can carry out frequency control according to the exhaust pressure detected by the pressure detection device when running at high water temperature, thereby improving the heating capacity and accelerating the water heating speed.

Description

Frequency change water heater and control method thereof
Technical field
The present invention relates to refrigerating field, particularly relate to a kind of frequency change water heater and control method thereof.
Background technology
Frequency change water heater has the advantage that heating efficiency is variable and capability improving is fast, can meet the demand of the quick water of user.Under pattern in rapid hot water demand, the ability of unit output strengthens, and compressor frequency needs continuous rising even move to highest frequency, and pressure is very high when the high water temperature operation of unit, if now still very large with the possibility of high frequency operation high voltage protective.
So in design for safety conventionally adopt unit operation to high water temperature significantly the method for frequency reducing reduce before shutting down to obtain system pressure, but in high water temperature section significantly when frequency reducing, the inevitable heating efficiency that significantly sacrifice frequency change water heater.
Summary of the invention
In order to overcome the deficiencies in the prior art, the invention provides a kind of frequency change water heater and control method thereof, it has solved and has reduced the problem that system pressure loses heating capacity simultaneously, and the present invention realizes the technical scheme that above-mentioned purpose adopts and is:
A kind of frequency change water heater, comprises compressor, also comprises pressure-detecting device and controller;
Described pressure-detecting device is arranged on the blast pipe place of described compressor, for detection of the pressure at expulsion of described compressor;
Described controller is electrically connected with described pressure-detecting device, in the time that described pressure-detecting device detects that the pressure at expulsion of described compressor reaches preset pressure, controls running frequency or the stoppage protection of described compressor.
More preferably, described pressure-detecting device comprises the first pressure detecting subelement and the second pressure detecting subelement;
The first preset pressure switch value of described the first pressure detecting subelement is less than the second preset pressure switch value of described the second pressure detecting subelement;
In the time that described pressure at expulsion is greater than or equal to the first preset pressure switch value of the first pressure detecting subelement, compressor holding frequency is constant and continue operation described in described controller control, and shuts down after water temperature reaches default water temperature;
In the time that described pressure at expulsion is greater than or equal to the second preset pressure switch value of the second pressure detecting subelement, compressor shutdown described in described controller control.
More preferably, described the first pressure detecting subelement and the second pressure detecting subelement are pressure sensor or mechanical pressure switch.
More preferably, described frequency change water heater also comprises cross valve, evaporimeter and water fluorine heat exchanger or condenser;
Described compressor, cross valve, evaporimeter, water fluorine heat exchanger or condenser are in turn connected to form refrigerating circuit.
The control method that a kind of frequency change water heater is also provided, comprises the steps:
The pressure-detecting device of frequency change water heater detects the pressure at expulsion of the compressor of described frequency change water heater;
The controller of described frequency change water heater, in the time that described pressure-detecting device detects that the pressure at expulsion of described compressor reaches preset pressure, is controlled running frequency or the stoppage protection of described compressor.
More preferably, running frequency or the stoppage protection of compressor, comprise the steps: described in described controller control
In the time that described pressure at expulsion is greater than or equal to the first preset pressure switch value of pressure-detecting device, compressor holding frequency is constant and continue operation described in described controller control, and shuts down after water temperature reaches default water temperature;
In the time that described pressure at expulsion is greater than or equal to the second preset pressure switch value of pressure-detecting device, compressor shutdown described in described controller control.
More preferably, in the time that described pressure at expulsion is greater than or equal to the second preset pressure switch value of pressure-detecting device, after compressor shutdown, also comprise the steps: described in described controller control
Be less than described the second preset pressure switch value and be more than or equal to downtime after Preset Time when the pressure at expulsion of described compressor is reduced to, described compressor starts operation again, and is being more than or equal to shutdown again after described the second preset pressure switch value;
Repeat aforesaid operations, until the water temperature of frequency change water heater is shut down after reaching default water temperature.
More preferably; be less than described the second preset pressure switch value and be more than or equal to downtime after Preset Time when the pressure at expulsion of described compressor is reduced to; described compressor starts operation again, and being more than or equal to shutdown again after described the second preset pressure switch value, comprises the steps:
If work as the second preset pressure switch value that described pressure at expulsion is greater than or equal to pressure-detecting device; when compressor shutdown; the running frequency of described compressor is fstop; in the time that described compressor starts operation again; described in described controller control, the running frequency f of compressor is less than its running frequency fstop in the time of described the second preset pressure switch value, i.e. f < fstop.
Further, the running frequency after the restarting of described compressor is 0.9 times that f is no more than its running frequency fstop in the time of described the second preset pressure switch value, i.e. f≤0.9fstop;
Described Preset Time is for being greater than or equal to 3 minutes.
Further, in the time that described frequency change water heater shuts down or heat end, also comprise the steps:
Described controller is removed the restriction of f≤0.9fstop, and in the time starting shooting next time, controls described compressor and still move with original frequency; Or described controller memory f≤0.9fstop, and in the time starting shooting next time, control the running frequency operation of described compressor with f≤0.9fstop.
The invention has the beneficial effects as follows:
The pressure at expulsion that frequency change water heater of the present invention and control method thereof can detect according to pressure-detecting device frequency change water heater in the time of high water temperature operation is carried out FREQUENCY CONTROL, has improved heating efficiency and has accelerated water heating speed.
Accompanying drawing explanation
Fig. 1 is frequency change water heater one embodiment schematic diagram of the present invention;
Fig. 2 is the control flow chart of frequency change water heater one embodiment shown in Fig. 1;
Fig. 3 is the control flow chart of another embodiment of frequency change water heater shown in Fig. 1.
The specific embodiment
In order to make object of the present invention, technical scheme and advantage clearer, below in conjunction with drawings and Examples, frequency change water heater of the present invention and control method thereof are further elaborated.Should be appreciated that specific embodiment described herein, only in order to explain the present invention, is not intended to limit the present invention.
Fig. 1 is frequency change water heater one embodiment schematic diagram of the present invention, as shown in Figure 1, frequency change water heater one embodiment comprises compressor 1, cross valve 2, evaporimeter 3, electric motor fan 31, restricting element 4, water fluorine heat exchanger or condenser 5 and controller (not shown), described compressor 1, described cross valve 2, described evaporimeter 3, described water fluorine heat exchanger or condenser 5 are in turn connected to form refrigerating circuit, restricting element 4 is set in described refrigerating circuit, on described compressor 1, be provided with gas-liquid separator 11, described refrigerating circuit is by water fluorine heat exchanger or condenser 5 heating waters, described frequency change water heater also comprises the pressure-detecting device that is arranged at compressor 1 blast pipe place, for detection of the pressure at expulsion of described compressor 1, described controller is electrically connected with described pressure-detecting device, in order to detect the pressure at expulsion of described compressor 1, for in the time that described pressure-detecting device detects that the pressure at expulsion of described compressor reaches preset pressure, control running frequency or the stoppage protection of described compressor.
More preferably, as a kind of embodiment, described pressure-detecting device comprises the first pressure detecting subelement 6 and the second pressure detecting subelement 7;
The preset pressure switch value of described the first pressure detecting subelement 6 is the first preset pressure switch value, the preset pressure switch value of described the second pressure detecting subelement 7 is the second preset pressure switch value, and described the first preset pressure switch value is less than the second preset pressure switch value;
In the time that described pressure at expulsion is greater than or equal to described the first preset pressure switch value, compressor holding frequency is constant and continue operation described in described controller control, and shuts down after water temperature reaches default water temperature;
In the time that described pressure at expulsion is greater than or equal to described the second preset pressure switch value, compressor 1 is shut down described in described controller control.
Preferably, described the first pressure detecting subelement 6 and the second pressure detecting subelement 7 are pressure sensor or mechanical pressure switch.
With reference to Fig. 2 and Fig. 3, being mechanical pressure switch take described the first pressure detecting subelement and the second pressure detecting subelement describes the control method of frequency change water heater of the present invention as example, described the first pressure detecting subelement 6 and the second pressure detecting subelement 7 are respectively pressure switch P1 and pressure switch P2, wherein, the preset pressure switch value of described the first pressure detecting subelement 6 is the first preset pressure switch value P1, the preset pressure switch value of described the second pressure detecting subelement 7 is the second preset pressure switch value P2, P1 < P2, the control method of described frequency change water heater, comprise the steps:
The pressure-detecting device of frequency change water heater detects the pressure at expulsion of the compressor of described frequency change water heater;
The controller of described frequency change water heater, in the time that described pressure-detecting device detects that the pressure at expulsion of described compressor reaches preset pressure, is controlled running frequency or the stoppage protection of described compressor 1.
More preferably, as a kind of embodiment, running frequency or the stoppage protection of compressor 1, comprise the steps: described in described controller control
In the time that described pressure at expulsion is greater than or equal to the first preset pressure switch value P1, compressor 1 holding frequency is constant and continue operation described in described controller control, and shuts down after water temperature reaches default water temperature;
In the time that described pressure at expulsion is greater than or equal to the second preset pressure switch value P2, compressor 1 is shut down described in described controller control.
Further, in the time that described pressure at expulsion is greater than or equal to the second preset pressure switch value P2, after compressor 1 is shut down described in described controller control, also comprise the steps:
Be less than described the second preset pressure switch value P2 and be more than or equal to downtime after Preset Time when the pressure at expulsion of described compressor 1 is reduced to, described compressor 1 starts operation again, and is being more than or equal to shutdown again after described the second preset pressure switch value P2;
Repeat aforesaid operations, until the water temperature of frequency change water heater is shut down after reaching default water temperature.
More preferably; as a kind of embodiment; be less than described the second preset pressure switch value P2 and be more than or equal to downtime after Preset Time when the pressure at expulsion of described compressor 1 is reduced to; described compressor starts operation again; and being more than or equal to shutdown again after described the second preset pressure switch value P2, comprise the steps:
If when described pressure at expulsion is greater than or equal to the second preset pressure switch value P2; when compressor 1 is shut down; the running frequency of described compressor 1 is fstop; in the time that described compressor 1 starts operation again; described in described controller control, the running frequency f of compressor 1 is less than its running frequency fstop in the time of described the second preset pressure switch value P2, i.e. f < fstop.
Preferably, the running frequency after the restarting of described compressor 1 is 0.9 times that f is no more than its running frequency fstop in the time of described the second preset pressure switch value P2, i.e. f≤0.9fstop;
Described Preset Time is for being greater than or equal to 3 minutes.
More preferably, as another kind of embodiment, in the time that described frequency change water heater shuts down or heat end, described controller is removed the restriction of f≤0.9fstop, and in the time starting shooting next time, controls described compressor still with original frequency operation, as shown in Figure 2; Or described controller memory f≤0.9fstop, and in the time starting shooting next time, control the running frequency operation of described compressor with f≤0.9fstop, as shown in Figure 3.
The pressure at expulsion that frequency change water heater of the present invention and control method thereof can detect according to pressure-detecting device frequency change water heater in the time of high water temperature operation is carried out FREQUENCY CONTROL, has improved heating efficiency and has accelerated water heating speed.
The above embodiment has only expressed several embodiment of the present invention, and it describes comparatively concrete and detailed, but can not therefore be interpreted as the restriction to the scope of the claims of the present invention.It should be pointed out that for the person of ordinary skill of the art, without departing from the inventive concept of the premise, can also make some distortion and improvement, these all belong to protection scope of the present invention.Therefore, the protection domain of patent of the present invention should be as the criterion with claims.

Claims (10)

1. a frequency change water heater, comprises compressor, it is characterized in that:
Also comprise pressure-detecting device and controller;
Described pressure-detecting device is arranged on the blast pipe place of described compressor, for detection of the pressure at expulsion of described compressor;
Described controller is electrically connected with described pressure-detecting device, in the time that described pressure-detecting device detects that the pressure at expulsion of described compressor reaches preset pressure, controls running frequency or the stoppage protection of described compressor.
2. frequency change water heater according to claim 1, is characterized in that:
Described pressure-detecting device comprises the first pressure detecting subelement and the second pressure detecting subelement;
The first preset pressure switch value of described the first pressure detecting subelement is less than the second preset pressure switch value of described the second pressure detecting subelement;
In the time that described pressure at expulsion is greater than or equal to the first preset pressure switch value of the first pressure detecting subelement, compressor holding frequency is constant and continue operation described in described controller control, and shuts down after water temperature reaches default water temperature;
In the time that described pressure at expulsion is greater than or equal to the second preset pressure switch value of the second pressure detecting subelement, compressor shutdown described in described controller control.
3. frequency change water heater according to claim 2, is characterized in that:
Described the first pressure detecting subelement and the second pressure detecting subelement are pressure sensor or mechanical pressure switch.
4. according to the frequency change water heater described in claims 1 to 3 any one, it is characterized in that:
Also comprise cross valve, evaporimeter and water fluorine heat exchanger or condenser;
Described compressor, cross valve, evaporimeter, water fluorine heat exchanger or condenser are in turn connected to form refrigerating circuit.
5. a control method for frequency change water heater, is characterized in that:
Comprise the steps:
The pressure-detecting device of frequency change water heater detects the pressure at expulsion of the compressor of described frequency change water heater;
The controller of described frequency change water heater, in the time that described pressure-detecting device detects that the pressure at expulsion of described compressor reaches preset pressure, is controlled running frequency or the stoppage protection of described compressor.
6. control method according to claim 5, is characterized in that, running frequency or the stoppage protection of compressor, comprise the steps: described in described controller control
In the time that described pressure at expulsion is greater than or equal to the first preset pressure switch value of pressure-detecting device, compressor holding frequency is constant and continue operation described in described controller control, and shuts down after water temperature reaches default water temperature;
In the time that described pressure at expulsion is greater than or equal to the second preset pressure switch value of pressure-detecting device, compressor shutdown described in described controller control.
7. control method according to claim 6, is characterized in that, in the time that described pressure at expulsion is greater than or equal to the second preset pressure switch value of pressure-detecting device, after compressor shutdown, also comprises the steps: described in described controller control
Be less than described the second preset pressure switch value and be more than or equal to downtime after Preset Time when the pressure at expulsion of described compressor is reduced to, described compressor starts operation again, and is being more than or equal to shutdown again after described the second preset pressure switch value;
Repeat aforesaid operations, until the water temperature of frequency change water heater is shut down after reaching default water temperature.
8. control method according to claim 7, is characterized in that:
Be less than described the second preset pressure switch value and be more than or equal to downtime after Preset Time when the pressure at expulsion of described compressor is reduced to; described compressor starts operation again; and being more than or equal to shutdown again after described the second preset pressure switch value, comprise the steps:
If work as the second preset pressure switch value that described pressure at expulsion is greater than or equal to pressure-detecting device; when compressor shutdown; the running frequency of described compressor is fstop; in the time that described compressor starts operation again; described in described controller control, the running frequency f of compressor is less than its running frequency fstop in the time of described the second preset pressure switch value, i.e. f < fstop.
9. control method according to claim 8, is characterized in that:
Running frequency after the restarting of described compressor is 0.9 times that f is no more than its running frequency fstop in the time of described the second preset pressure switch value, i.e. f≤0.9fstop;
Described Preset Time is for being greater than or equal to 3 minutes.
10. control method according to claim 9, is characterized in that:
In the time that described frequency change water heater shuts down or heat end, also comprise the steps;
Described controller is removed the restriction of f≤0.9fstop, and in the time starting shooting next time, controls described compressor and still move with original frequency; Or described controller memory f≤0.9fstop, and in the time starting shooting next time, control the running frequency operation of described compressor with f≤0.9fstop.
CN201210452507.1A 2012-11-13 2012-11-13 variable-frequency water heater and control method thereof Active CN103808012B (en)

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CN103808012B CN103808012B (en) 2016-06-08

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Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
TWI597463B (en) * 2016-01-25 2017-09-01 保音股份有限公司 A method for detecting an exhaust line of a water heater device
CN111473466A (en) * 2020-04-21 2020-07-31 宁波奥克斯电气股份有限公司 Frequency control method and air conditioner
US10941955B2 (en) 2017-10-27 2021-03-09 Dometic Sweden Ab Systems, methods, and apparatuses for providing communications between climate control devices in a recreational vehicle
CN112856856A (en) * 2020-05-22 2021-05-28 青岛海尔新能源电器有限公司 Heat pump unit control method and heat pump unit
WO2021179644A1 (en) * 2020-03-13 2021-09-16 青岛海尔中央空调有限公司 Water outlet temperature correction-based unit starting/stopping control method, system and apparatus
CN113739350A (en) * 2021-09-23 2021-12-03 宁波奥克斯电气股份有限公司 Low-temperature heating frequency conversion control method and device, storage medium and air conditioner
CN113883681A (en) * 2021-09-28 2022-01-04 青岛海尔中央空调有限公司 Control method for refrigeration system and refrigeration system
US11254183B2 (en) 2017-08-25 2022-02-22 Dometic Sweden Ab Recreational vehicle, cooling device, controlling system and method for controlling the cooling device

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EP1972871A2 (en) * 2007-03-19 2008-09-24 Mitsubishi Electric Corporation Hot water system
JP2009150609A (en) * 2007-12-21 2009-07-09 Corona Corp Heat pump type water heater
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JP2008202809A (en) * 2007-02-16 2008-09-04 Matsushita Electric Ind Co Ltd Heat pump type water heater
EP1972871A2 (en) * 2007-03-19 2008-09-24 Mitsubishi Electric Corporation Hot water system
JP2009150609A (en) * 2007-12-21 2009-07-09 Corona Corp Heat pump type water heater
JP2009243774A (en) * 2008-03-31 2009-10-22 Panasonic Corp Heat pump type water heater
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Cited By (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
TWI597463B (en) * 2016-01-25 2017-09-01 保音股份有限公司 A method for detecting an exhaust line of a water heater device
US11254183B2 (en) 2017-08-25 2022-02-22 Dometic Sweden Ab Recreational vehicle, cooling device, controlling system and method for controlling the cooling device
US11919363B2 (en) 2017-08-25 2024-03-05 Dometic Sweden Ab Recreational vehicle, cooling device, controlling system and method for controlling the cooling device
US10941955B2 (en) 2017-10-27 2021-03-09 Dometic Sweden Ab Systems, methods, and apparatuses for providing communications between climate control devices in a recreational vehicle
WO2021179644A1 (en) * 2020-03-13 2021-09-16 青岛海尔中央空调有限公司 Water outlet temperature correction-based unit starting/stopping control method, system and apparatus
CN111473466A (en) * 2020-04-21 2020-07-31 宁波奥克斯电气股份有限公司 Frequency control method and air conditioner
CN111473466B (en) * 2020-04-21 2022-03-22 宁波奥克斯电气股份有限公司 Frequency control method and air conditioner
CN112856856A (en) * 2020-05-22 2021-05-28 青岛海尔新能源电器有限公司 Heat pump unit control method and heat pump unit
CN112856856B (en) * 2020-05-22 2023-02-28 青岛海尔新能源电器有限公司 Heat pump unit control method and heat pump unit
CN113739350A (en) * 2021-09-23 2021-12-03 宁波奥克斯电气股份有限公司 Low-temperature heating frequency conversion control method and device, storage medium and air conditioner
CN113739350B (en) * 2021-09-23 2022-05-03 宁波奥克斯电气股份有限公司 Low-temperature heating frequency conversion control method and device, storage medium and air conditioner
CN113883681A (en) * 2021-09-28 2022-01-04 青岛海尔中央空调有限公司 Control method for refrigeration system and refrigeration system

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