JP2633415B2 - Control device for air conditioner - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control device for an air conditioner such as an air handling unit used for air conditioning of a building or the like.

[0002]

2. Description of the Related Art In recent years, there has been a demand for a control device for an air conditioner to improve comfort and reduce driving power.

A conventional air conditioner control device, for example, an air handling unit as an air conditioner, has a general configuration as shown in Japanese Patent Application Laid-Open No. 61-220611. Hereinafter, a conventional control device for an air conditioner will be described with reference to FIGS.

[0004] As shown in the figure, a cold / hot water coil 102 and a blower 1 for sending air heat exchanged by the cold / hot water coil 102 into a room are provided in a housing 101 of the air handling unit.
03, a filter 104 and an air supply duct 105
To the air-conditioned room 106 via the The casing 101 of the air handling unit and the room to be conditioned 106 are connected by a return air duct 107. Inside the return air duct 107, the air-handling unit housing 1
Return air temperature sensor 108 that measures the temperature of air returning to 01
The air supply duct 105 is provided with an air supply temperature sensor 109 for measuring the temperature of the air supplied from the housing 101 of the air handling unit to the room to be air-conditioned 106. The signal of the return air temperature sensor 108 and the signal of the supply air temperature sensor 109 are input to the return air temperature comparison means 111 and the supply air temperature comparison means 112 of the control device 110, respectively.

The control device 110 includes a return air temperature setting means 113 for setting a return air temperature set value, a return air temperature comparison means 111 for comparing a signal of the return air temperature and a signal of the return air temperature set value, and a return air temperature comparison means. Air supply amount calculation means 115 which receives the signal from 111 to determine the air supply amount and controls the blower 103 via an inverter 114, and air supply temperature setting means 116 which sets an air supply temperature set value, supply air temperature and air supply Supply air temperature comparison means 112 for comparing the signal of the air temperature set value, receiving the signal from the air supply temperature comparison means 112, determining the opening of the valve 117 for adjusting the water amount of the cold / hot water coil 102, and controlling the valve 117 Through a valve driving device 118.

Next, the operation of the above configuration will be described. Air is supplied from the blower 103 to the air-conditioned room 106 through the air supply duct 105. The air in the air-conditioned room 106 is returned to the housing 101 of the air handling unit through the return air duct 107. The air is filtered 10
4. The air is supplied to the air-conditioned room 106 through the air supply duct 105 again by the blower 103 after passing through the cold / hot water coil 102.
The return air temperature sensor 108 and the supply air temperature sensor 109 send respective temperature signals to the return air temperature comparison means 111 and the supply air temperature comparison means 112 in the control device 110 to control the air handling unit.

Next, the operation and operation of the control device 110 will be described. The operation of the control device 110 is divided into a part that controls the blower 103 by the return air temperature and a part that controls the valve 117 by the supply air temperature.

In FIG. 14, return air temperature setting means 113
Then, the operator sets the return air temperature set value (T _R ) so that the room temperature becomes comfortable. Return air temperature sensor 108 detects return air temperature t _R. Return air temperature comparison means 111

[0009]

(Equation 3)

Thus, the deviation e _R of the return air temperature is obtained.
The supply air amount calculation means 115 calculates the return air temperature deviation e _R

[0011]

(Equation 4)

The PI calculation shown in FIG. 1 is performed, and the rotation speed V _{R of the} blower is calculated.
Is determined, and a command signal is sent to the inverter 114 to change the rotation speed of the blower 103. Thereafter return air temperature sensor 10
8, the same operation is repeated. Here, K _CR is a proportional gain and T _iR is an integration time, a parameter given by the operator with a constant value.

In FIG. 15, supply air temperature setting means 116
Then, the operator sets the supply air temperature set value (T _s ) so that the room temperature becomes comfortable. The supply air temperature sensor 109 detects the supply air temperature t _s . In the supply air temperature comparison means 112

[0014]

(Equation 5)

Thus, a deviation e _s of the supply air temperature is obtained.
The flow rate calculating means 119 calculates the deviation e of the obtained supply air temperature.
from _s

[0016]

(Equation 6)

The PI operation shown in the following is performed to determine the valve opening U _v , and a command signal is sent to the valve driving device 118 to change the opening of the valve 117. Thereafter, the flow returns to the supply air temperature sensor 109 and the same operation is repeated. Here, K _CS is a proportional gain, T _iS
Is a parameter given a constant value by the operator during the integration time.

The above two operations attempt to keep the room temperature comfortable.

[0019]

In such a conventional control device for an air conditioner, a control loop for controlling the return air temperature by changing the number of revolutions of a fan and an air supply by changing the opening of a valve are provided. The return air temperature and the supply air temperature are controlled by two independent one-input, one-output control loops of the control loop that controls the temperature. However, when the fan speed is changed, not only the return air temperature but also the supply air temperature is controlled. The air temperature also changes. Changing the opening of the valve changes not only the supply air temperature but also the return air temperature.
Therefore, there is a problem that two control loops interfere with each other and a good control result cannot be obtained.

An object of the present invention is to solve the above-mentioned problems, and a first object of the present invention is to provide an air conditioner control device capable of maintaining a comfortable indoor temperature by performing a multi-input multi-output control. Is what you do.

A second object of the present invention is to provide a control device for an air conditioner which can change the linear operation coefficient of the control amount operation means depending on the current control condition and can keep the room temperature comfortable in any case. .

A third object of the present invention is to provide an air conditioner control device capable of changing both the linear operation coefficient of the control amount calculating means depending on the control situation and maintaining both the indoor temperature and the indoor CO ₂ concentration comfortably. is there.

[0023]

A first air conditioner control device for achieving the first object of the present invention comprises a plurality of sensors (measurement of each sensor) for measuring indoor environment such as temperature and humidity. and the values and _{y 1, y 2 ··· y n} ), a plurality of actuators for changing the capacity of the air conditioner, y ₁
A target value r ₁ for y ₂ , a target value r ₂ for y ₂ ,
A plurality of target value setting means for setting · · y _n the target value r _n for each control quantity u ₁ from the y ₁ and r ₁ Tokyo,
... said control quantity u ₂ from the y ₂ and r ₂ Metropolitan y _n and r
a plurality of control amount calculation means for calculating respective control quantity u _n by equation (1) and a _n, the u _1, u ₂ ··· u plurality of manipulated variable by _n from the equation (2) U _1, U ₂・ ・ ・ U _m
An operation amount calculating means for calculating a manipulated variable of the plurality of actuators are those Karakara configured with a plurality of operating means for operating the actuator such that U _1, U ₂ ··· U _m respectively.

The second means for achieving the second object is a current operation amount U calculated by the operation amount calculating means.
_1, U ₂ · · · formed a fuzzy inference means for changing the operation coefficient of manipulated variable calculation means by fuzzy inference from U _m in addition to the first means.

A third means for attaining the third object includes a return air temperature sensor for measuring the temperature of the return air to the air conditioner, and a CO ₂ sensor for measuring the indoor CO ₂ concentration. An air supply temperature sensor that measures the temperature of the air blown out of the air conditioner is provided as a sensor, and a blower that changes the air volume of the air blown out of the air conditioner, and the amount of hot or cold water or refrigerant flowing through the piping of the heat exchanger And an external air damper that changes the exchange ratio between the outside air and the indoor air as an actuator.

[0026]

According to the first aspect of the present invention, the operation amount of each actuator is calculated from a measured value of each sensor and a target value corresponding thereto by a simple formula, and each actuator is operated with high accuracy to thereby obtain a room temperature. Can be kept comfortable.

Further, according to the configuration of the second means, the control state, that is, the current operation state (operating amount) of each actuator is calculated, and the linear operation coefficient of the control amount calculating means is changed by the calculated operating amount. In any case, the room temperature can be kept comfortable.

Further, with the configuration of the third means, the linear operation coefficient of the control amount calculating means is changed according to the control situation, so that the room temperature and the indoor CO ₂ concentration can be kept comfortable in any case.

[0029]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be described below with reference to FIGS. For the sake of concreteness, a control device in the case of using a return air temperature sensor and a supply air temperature sensor as sensors and a valve and a blower as actuators will be described using an air handling unit as an example as in the conventional example. . Since the configuration of the air handling unit is the same as that of the conventional example, the description will be omitted.

In FIG. 1, the measured value y ₁ of the return air temperature sensor 108 for detecting the temperature in the return air duct 107 and the target return air temperature value r ₁ set in the return air temperature target value setting means 1a are controlled. is input to an amount calculation means 2a, the control amount calculation means 2a outputs the control amount u ₁ to the operation amount calculation unit 3a. Similarly, the measured value y ₂ and the supply air temperature target value setting means 1b of the supply air temperature sensor 109 for detecting the temperature in the supply duct 105
Supply air temperature target value r ₂ set in is input to the control amount arithmetic means 2b, the control amount calculation means 2b outputs a control amount u ₂ to the operation amount calculation unit 3a. Operation amount computing means 3a outputs a manipulated variable U ₁ in the valve operating means 4a, and outputs the manipulated variable U ₂ to the blower operating means 4b. The valve operating means 4a is a valve 117
Output an electrical signal to the Similarly, the blower operation means 4b outputs an electric signal to the blower 103.

The operation of the above configuration will be described. 2, return air return air temperature target value r ₁ by the temperature target value setting means 1a at the operator set, supply air temperature target value r ₂ is set by the operator in the supply air temperature target value setting means 1b . The return air temperature sensor 108 measures the return air temperature y ₁ , and the control amount calculation means 2 a

[0032]

(Equation 7)

When the calculation shown in the following is performed and n is 1, the control amount u ₁
Is required. Here, y ₁ ^′ , y ₁ ^″ , and u _1B are y
First order differential value of _1, the second-order differential value of the y _1, which is the last u _1. Also, G ₁ is the gain, zeta ₁ is the damping factor,
ω ₁ is a natural frequency and is a parameter given a constant value by the operator.

Note that (Equation 7) is based on "JAACE '85-
5 32nd System and Control Research Presentation Performance P55-
P56 "TDC (Time Delay Contr
ol), the reference model is a second-order lag system model

[0035]

(Equation 8)

It is derived if selected. Here, y _Mn in the output of the reference _{model, y Mn ', y Mn'} 1 order derivative of the 'each y _Mn, a second order derivative in the y _Mn. Similarly, the supply air temperature sensor 109 measures the supply air temperature y ₂ , and the control amount calculation means 2 b

[0037]

(Equation 9)

The control amount u ₂ is obtained by performing the calculation shown in the following. ^{_{Here, y 2 ', y 2 "}} , 1 order derivative of the respective u _2B y _2, 2-order differential value of y _2, a last u ₂ .G ₂ gain, zeta ₂ is the damping factor, omega _The parameter ₂ is a natural frequency and is a parameter given a constant value by the operator.The operation amount calculating means 3a calculates the control amount u ₁ and the control amount u ₂

[0039]

(Equation 10)

The operation amount U ₁ and the operation amount U ₂ are determined by performing the linear operation shown in FIG. 3, and U ₁ is output to the valve operation means 4a and U ₂ is output to the blower operation means 4b. Here, a ₁₁ ~a ₂₂ is a parameter that is given a constant value by the operator by linear calculation coefficient. An electric signal corresponding to U ₁ in the valve operating means 4a for operating the feed valve 117 to the valve 117. Similarly, blowing an electrical signal corresponding to U ₂ in the blower operating means 4b machine 10
3 and the blower 103 is operated. Thereafter, the operation returns to the return air temperature sensor 108 and the same operation is repeated.

As described above, according to the control device for an air conditioner of the first embodiment of the present invention, the TDC is applied to the air-conditioning control, and the second-order lag system model is selected as the reference model. ), (Equation 10), it is possible to calculate and control by a microcomputer, that is, to calculate and operate the valve operation amount and the blower operation amount simultaneously based on the return air temperature and the supply air temperature. In order to prevent interference between the valve and the blower, as shown in FIG. 3, the room temperature is kept comfortable to keep the return air temperature and the supply air temperature at target values, and a general control method as shown in FIG. A better control result than a certain PID control result is obtained, and the operation of the air conditioner can be performed without waste.

Next, a second embodiment of the present invention will be described with reference to FIGS.
This will be described with reference to FIG. The second embodiment is configured by adding fuzzy inference means 6a to the first embodiment. Therefore, the configuration of the air handling unit is the same as that of the conventional example, and the description is omitted. The same parts as those in the first embodiment are denoted by the same reference numerals, and the description is omitted. FIG.
A fuzzy inference unit 6a is a linear operation coefficients of the operation amount calculation unit 3a the operation amount of the current operating status of the operation amount calculation operation amount calculated by means 3a U ₁ and U ₂ values clogging valve 117 and the blower 103 in ₁₁ changes the value of ~a _22.

Next, the operation of the fuzzy inference means 6a will be described. The fuzzy inference means 6 a
Based on the values of the manipulated variables U ₁ and U ₂ calculated in a

[0044]

[Equation 11]

Fuzzy inference indicated by the rule of
₁₁ determines the value of ~a _22. Here, S is Small, B
Represents Big and M represents Middle. Further, membership functions of U ₁ and U ₂ is a ₁₁ ~a ₂₂ as in FIG. 6
Is defined as shown in FIG. Here, a _max and a _min are parameters given a constant value by the operator.

As described above, according to the control apparatus for an air conditioner of the second embodiment of the present invention, the operation amount of the current operation state of each actuator is calculated and determined. Is difficult to control because the values of a _{11 to} a ₂₂ are changed by fuzzy inference means in consideration of the fact that the air volume is small and the supply air temperature is likely to change, and the values of a _{11 to} a ₂₂ are changed by the fuzzy inference means in consideration of the valve opening and the S-shaped characteristic of the flow rate Interim period (May, June, 10
Even when the air-conditioning load is small (e.g., Monday, November), good control is possible, and the room temperature can be kept comfortable.

FIGS. 8 to 11 show a third embodiment of the present invention.
This will be described with reference to FIG. The third embodiment is different from the first and second embodiments in that a CO ₂ concentration sensor is used as a sensor, an outside air damper is used as a target value setting unit, and a CO ₂ concentration target value setting unit is used as an operation unit. It is configured as Further, the operation of the operation amount calculating means and the operation of the fuzzy inference means are different. Therefore, in the configuration of the air handling unit, the same parts as those in the conventional example are denoted by the same reference numerals, and description thereof will be omitted. The same parts as those in the first and second embodiments are denoted by the same reference numerals, and the description is omitted.

In FIG. 8, the CO ₂ concentration sensor 7 measures the CO ₂ concentration in the room to be air-conditioned 106. Part of the air returning from the air-conditioned room 106 to the casing 101 of the air handling unit through the return air duct 107 is exchanged with the outside air through the outside air duct 8. The exchange ratio with the outside air changes according to the opening degree of the outside air damper 9. The opening degree of the outside air damper 9 is controlled by the outside air damper operating means 4c. The signal from the CO ₂ concentration sensor 7 is input to the control device 10, and a signal is output from the control device 10 to the outside air damper operating means 4 c.

Next, the configuration of the control device according to the third embodiment will be described. In FIG. 9, the measured value y ₃ of the CO ₂ sensor 7 for detecting the CO ₂ concentration in the room to be air-conditioned 106 and the CO ₂ concentration target value r ₃ set in the CO ₂ concentration target value setting means 1c.
Is input to the control amount calculating means 2c, and the control amount calculating means 2c
Outputs the control amount u ₃ to the operation amount calculating means 3b. Manipulated variable calculation means 3b outputs the manipulated variable U ₁ in the valve operating means 4a a manipulated variable U ₂ to the blower operating means 4b the operating amount U ₃ to the outside air damper operating means 4c. The outside air damper operating means 4c outputs an electric signal to the outside air damper 9. Fuzzy inference means 6b
Are the operation amounts U ₂ and U calculated by the operation amount calculation means 3b.
The values of α and β, which are the linear operation coefficients of the operation amount calculation means 3b, are changed from the value of ₃ , ie, the operation amounts of the blower 103 and the outside air damper 9.

Next, the operation of the third embodiment will be described.
Is CO ₂ concentration target value r ₃ is set by the operator in the CO ₂ concentration target value setting means 1c in FIG. CO ₂
The CO ₂ concentration y ₃ is measured from the sensor 7 and is controlled by the control amount calculating means 2c.

[0051]

(Equation 12)

The control amount u ₃ is obtained by performing the calculation shown in the following. ^{_{Here, y 3 ', y 3 "}} , u 3B are first order differential value of each y _3, 2-order differential value of y _3, a last u _3. Also, G
₃ is a gain, ζ ₃ is a damping factor, and ω ₃ is a natural frequency, all of which are parameters given constant values by an operator. The operation amount calculating means 3b calculates the control amount u ₁ , the control amount u _2, and the control amount u ₃

[0053]

(Equation 13)

The operation amount U ₁ , the operation amount U ₂ and the operation amount U ₃ are determined by performing the linear operation shown in the following, and U ₁ is transmitted to the valve operation means 4 a, U ₂ is transmitted to the blower operation means 4 b, and U ₃ is transmitted to the outside air damper operation means 4 c. Output to Here, G _S , G _R , G _C , α, and β are linear operation coefficients, and G _S , G _R , and G _C are given constant values by the operator, and α, β are changed by the fuzzy operation means 6b. Is done. An electric signal corresponding to the U ₃ in outdoor air damper operating means 4c for operating the outdoor air damper 9 is sent to the outdoor air damper 9. Thereafter, the operation returns to the return air temperature sensor 108 and the same operation is repeated.

[0055] Also, when you describe the operation of the fuzzy inference means 6b, the fuzzy inference means 6b is based on the value of the operation manipulation amount calculated by weight calculating unit 3b U ₂ and the operation amount U ₃

[0056]

[Equation 14]

The fuzzy inference indicated by the rule of
And determine the value of β. Here, S is Small, B
Is Big, NB is Not Big, NS is Not Sm
means all. The membership functions of U ₂ and U ₃ are defined as shown in FIG. 11, and the membership functions of α and β are defined as shown in FIG.

As described above, according to the control device for the air conditioner of the third embodiment of the present invention, when the air conditioning load is large and the amount of air blown by the blower is large, the return air temperature, the supply air temperature, and the CO ₂ concentration are all set to the target values. However, as the air-conditioning load decreases and the amount of air blown by the blower decreases, the values of the linear operation coefficients α and β are changed by fuzzy inference means to stop the control of the supply air temperature and return air temperature. The control is gradually shifted to control to keep only the indoor CO ₂ concentration at the target value and the indoor temperature and the indoor CO ₂ concentration can be maintained in a comfortable state even when the air conditioning load is small. In addition, since the control is gradually shifted by the fuzzy inference, the operation can be performed without waste without causing any inconvenience due to the shift of the control.

Although the configuration and operation of the control device for an air conditioner of the present invention have been described using an example of a water piping type air conditioner such as an air handling unit, a refrigerant piping type air conditioner such as a packaged air conditioner is described. It is needless to say that the same effect can be obtained even if it is used.

[0060]

As is apparent from the above embodiments, according to the present invention, the operation amounts of the plurality of actuators are determined by using a simple formula which can be used by the microcomputer in order to keep all the measurement values of the plurality of sensors at the target values. Therefore, it is possible to provide a control device for an air conditioner that has an effect of eliminating interference between actuators, maintaining a comfortable indoor temperature, and performing operation without waste.

In any case, since the operation coefficient is changed while observing the current operation state (operating amount) of each actuator, the control device of the air conditioner can maintain the indoor temperature in a comfortable state. Can be provided.

Furthermore, a control device for an air conditioner that can maintain the indoor temperature and the indoor CO ₂ concentration in a comfortable state in any case can be provided.

[Brief description of the drawings]

FIG. 1 is a diagram showing a control device of an air conditioner according to a first embodiment of the present invention.

FIG. 2 is a flowchart showing an outline of the operation of the control device.

FIG. 3 is a diagram showing a control result of room temperature and supply air temperature by TDC.

FIG. 4 is a diagram showing a control result of a room temperature and an air supply temperature by PID control;

FIG. 5 is a diagram showing a control device of an air conditioner according to a second embodiment of the present invention.

FIG. 6 is a diagram showing membership functions of U ₁ and U ₂ in fuzzy inference means of the control device.

[7] a ₁₁ ~ in fuzzy inference means of the same control device
shows a membership function of a ₂₂

FIG. 8 is a diagram showing a schematic configuration of an air conditioner according to a third embodiment of the present invention.

FIG. 9 is a diagram showing a control device for an air conditioner according to a third embodiment of the present invention.

FIG. 10 is a flowchart outlining the operation of the control device;

FIG. 11 shows U ₂ in the fuzzy inference means of the control device.
Shows a membership function of U ₃ and

FIG. 12 is a diagram showing membership functions of α and β in fuzzy inference means of the control device.

FIG. 13 is a diagram showing a schematic configuration and a control device of a conventional air conditioner.

FIG. 14 is a flowchart showing an outline of an operation of controlling the rotation speed of the blower by the control device;

FIG. 15 is a flowchart showing an outline of the operation of the control device for controlling the valve of the cold / hot water coil.

[Explanation of symbols]

1a return air temperature target value setting means 1b supply air temperature target value setting means 1c CO ₂ concentration target value setting means 2a control amount calculation means 2b control amount calculation means 2c control amount calculation means 3a operation amount calculation means 3b manipulated variable computing means 4a Valve operating means 4b Blower operating means 4c Outside air damper operating means 5a Low pass filter 5b Low pass filter 6a Fuzzy inference means 6b Fuzzy inference means 7 CO ₂ sensor 8 Outside air duct 9 Outside air damper 103 Blower 108 Return air temperature sensor 109 Supply air temperature sensor 117 valve

Claims (3)

(57) [Claims] A plurality of sensors for measuring indoor environment such as temperature and humidity (hereinafter, measurement values of each sensor are represented by y ₁ , y _2, ...).
· A y _n and), and a plurality of actuators for changing the air-conditioning capacity of the air conditioner (hereinafter an operation amount of each actuator and _{U 1, U 2 ··· U m} ), the target relative to the y ₁ The value r ₁ , the target value r ₂ for y _{2 ,.}
A plurality of target value setting means for setting respective target value r _n In contrast, a control amount u ₁ from the y ₁ and r ₁ Prefecture, wherein y ₂
A control amount u _n from the r ₂ Metropolitan control amount U ₂ and ... the y _n and r _n from Equation 1] From a plurality of control amount calculating means respectively calculating by the following formulas and u ₁ , u ₂ ... U _n. Operation and operation amount calculating means for calculating a plurality of manipulated variables _{U 1, U 2 ··· U m} , the actuator so that the operations of the plurality of actuators is U _1, U ₂ ··· U _m respectively by A control device for an air conditioner, comprising: a plurality of operating means. Wherein characterized in that a fuzzy inference means for changing the operation coefficient of manipulated variable calculation means by fuzzy inference from the operation amount calculation current operation amount calculated by the means U _1, U ₂ ··· U _m The control device for an air conditioner according to claim 1, wherein 3. A CO ₂ for measuring the return air temperature sensor for measuring the temperature of went back air to the air conditioner, the CO ₂ concentration in the chamber
A sensor, a supply air temperature sensor that measures the temperature of the air blown out of the air conditioner as a sensor, a blower that changes the air volume of the air blown out of the air conditioner, and hot or cold water or refrigerant flowing through the piping of the heat exchanger 2. A valve according to claim 1, further comprising a valve for changing an amount of air and an outside air damper for changing an exchange ratio between outside air and room air.
Or the control device of the air conditioner according to 2.