JPH05106929A - Space heating controller for multichamber air conditioner - Google Patents

Abstract

(57) [Summary] [Purpose] In a multi-room air conditioner that controls the opening degree of the electric expansion valve of the indoor air conditioner to control the air conditioning capacity, the opening degree of the indoor expansion valve is appropriately controlled. Smoothly control the air conditioning temperature. [Structure] Supercooling degree detection means 18α (where α = a,
b, c), the first target disclosure calculation means 22 based on the deviation between the room temperature and the target temperature of the air conditioning, the second target opening calculation means 23 based on the degree of supercooling, and switching between these calculation means. Output of the memory device 25 that stores a control rule based on an empirical rule, the supercooling degree detection means 18α, the first target opening degree calculation means 22 and the second target opening degree calculation means 23 When,
It is composed of an opening degree determining means 27 and an opening degree controlling means 28 for determining the opening degree of the indoor electric expansion valve 17α by a fuzzy inference means 26 for performing a fuzzy logic operation from a control rule based on experience extracted from the memory device 25. ..

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a multi-room air conditioner (hereinafter referred to as an air conditioner), and in particular, by changing the air conditioning capacity by controlling the opening of an electric expansion valve, The present invention relates to a heating control device for a multi-room air conditioner that smoothly controls room temperature adjustment.

[0002]

2. Description of the Related Art In recent years, the mainstream of air conditioning in a building or the like is a so-called multi-room type air conditioner in which an indoor unit is installed in each room with a different air conditioning load and is controlled by one outdoor unit. is there. Such an air conditioner is disclosed in
A device provided with an electric expansion valve disclosed in Japanese Patent Laid-Open No. 63-180051 is well known.

FIG. 4 is a block diagram showing the structure of a conventional heating control device in an air conditioner using an electric expansion valve.
In the figure, 1 is a compressor, 2 is a condenser, 3 is an electric expansion valve, 4 is an evaporator, and these form a refrigerant circulation system 5. Further, 6 is room temperature detecting means, and 7 is the electric expansion valve 3 according to the deviation between the room temperature of the detected output and the room temperature target temperature.
Is a target opening calculation means for calculating the target opening value, and 8 is an opening control means for receiving the output of the target opening calculation means 7 and setting the opening of the electric expansion valve 3 to a preset target opening. To control the value. Reference numeral 9 is a superheat detection means for detecting the superheat of the refrigerant, and 10
Is a protection means prior to the opening control means 8.

In the operation of the conventional air conditioner thus configured, first, the target opening value of the electric expansion valve 3 according to the deviation between the room temperature and the room temperature target temperature during the air conditioning operation is calculated by the target opening calculating means 7 The opening degree control means 8 controls increase / decrease of the opening degree of the electric expansion valve 3 so that the target opening degree value is obtained.
As a result, the flow rate of the refrigerant to the evaporator 4 is appropriately adjusted, and the air conditioning load and the air conditioning capacity in the room correspond well, and the room is comfortably air conditioned.

Now, for example, when the air-conditioning load decreases and the superheat degree of the refrigerant decreases, the superheat degree of the refrigerant received by the superheat degree detecting means 9 is below a predetermined superheat value for so-called wet operation. , The protection means 10 in preference to the opening degree control means 8
Reduces the opening degree of the electric expansion valve 3, and as a result, the degree of superheat of the refrigerant increases, and the occurrence of a wet state of the refrigerant is effectively suppressed and prevented.

[0006]

However, in the above-mentioned configuration, the opening degree control of the electric expansion valve 3 changes greatly at a predetermined superheat value. Therefore, turbulence occurs at room temperature controlled near the boundary of superheat. Further, since there is no protection means provided when the degree of superheat is excessive, uneven distribution of the refrigerant occurs and the capacity distribution between the indoor units cannot be performed properly. Moreover, the above-mentioned publication also applies to heating. In the case of this heating, control by supercooling is not a method controlled by superheat, but an appropriate method.

The present invention has been made in view of the above-mentioned conventional air conditioner, and prevents the excessive increase or decrease of the degree of supercooling of the refrigerant, smoothly shifts the boundary of the cooling, and cools it at room temperature. An object of the present invention is to provide a heating control device for a multi-room air conditioner that prevents turbulence.

[0008]

SUMMARY OF THE INVENTION The present invention is directed to a first indoor expansion valve for controlling an air conditioning temperature in a multi-room air conditioner by controlling a deviation between a room temperature and a preset air conditioning temperature.
And a second target of the indoor electric expansion valve, which is calculated based on the degree of supercooling detected in the pipe section between the indoor heat exchanger and the indoor electric expansion valve. A fuzzy logic operation is performed by means for calculating the degree of opening and the control rule for the degree of opening of the indoor electric expansion valve based on an empirical rule for obtaining the optimum degree of opening from the first and second target openings. And a fuzzy inference means for performing the fuzzy inference, and controlling the opening degree of the indoor electric expansion valve based on the result of the fuzzy inference.

[0009]

According to the present invention, the first target opening degree of the electric expansion valve on the indoor side is calculated based on the temperature deviation between the detected room temperature and the set target temperature, and the indoor heat exchanger is calculated. The second target opening degree of the indoor electric expansion valve is calculated based on the degree of supercooling detected by the pipe between the indoor electric expansion valve and the indoor expansion valve, and the result and the detected degree of supercooling are calculated. , The indoor electric expansion valve opening is determined by fuzzy inference by a control rule based on empirical rules, and the indoor electric expansion valve opening is controlled to the determined opening, so that the air conditioning performed by each indoor unit is controlled. Is smoothly and comfortably controlled without temperature disturbance.

[0010]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram showing the configuration of a heating control device for a multi-room air conditioner according to an embodiment of the present invention. Reference numeral 11 is an outdoor unit having a variable capacity compressor 12 and an outdoor heat exchanger 13. It is composed of an outdoor expansion valve 14 and a four-way valve 15.

Further, 16a, 16b, 16c (hereinafter, referred to as 16α, α represents any one of a, b or c, and the same symbols are selected for other symbols in the same indoor unit. The indoor electric expansion valve 17α, the subcooling degree detecting means 18α, and the room temperature detecting means 19
α, a temperature setting means 20α, and an indoor heat exchanger 21α, and the supercooling degree detecting means 18α is a pipe connecting between the indoor heat exchanger 21α and the indoor electric expansion valve 17α. It is installed in.

Reference numeral 22 denotes a first target opening calculating means, which is a room temperature detected by the room temperature detecting means 19α and a temperature setting means 20α.
Based on the deviation from the target temperature set by
The first target opening of 17α is calculated. Reference numeral 23 denotes a second target opening degree calculating means, which calculates a second target opening degree of the indoor electric expansion valve 17α from the supercooling degree detected by the supercooling degree detecting means 18α. Further, 24 is a microprocessor, which is composed of a memory device 25 for temporarily storing the control rule and a fuzzy inference means 26. Reference numeral 27 denotes an opening degree determining means, which determines the opening degree of the indoor electric expansion valve 17α based on the result inferred by the fuzzy inference means 26, and the opening degree of the indoor electric expansion valve 17α is determined according to the determination. Controlled by.

The present invention has the above configuration and operates as described below.

First, the deviation between the room temperature detected by the room temperature detecting means 19α and the target temperature set by the temperature setting means 20α is obtained by the first target opening degree calculating means 22, and the first target opening degree is calculated from the deviation. The means 22 calculates the _first target opening degree S ₁ . Further, the second target opening degree calculating means 23 calculates the second target opening degree S ₂ from the supercooling degree SC detected by the supercooling degree detecting means 18α.

The first target opening S ₁ , the second target opening S _2, and the detected supercooling degree SC calculated as described above are input to the fuzzy inference means 26. The memory device 25 stores the control rules necessary for the fuzzy inference executed by the fuzzy inference means 26.

The fuzzy inference is executed based on the control rule. In this embodiment, the following three rules R1, R2 and R3 are used.
Was used.

Rule R1: If the degree of supercooling SC is small S, the opening degree is the second target opening degree S ₂ Rule R2: If the degree of supercooling SC is medium M, the opening degree is the second degree 1 target opening S ₁ rule R3: If the degree of supercooling SC is large B, the opening is the second target opening S ₂ This language rule is obtained by the inventor of the present invention from many experimental data. Electric expansion valve for indoor air conditioner, which was obtained from the rule of thumb
This is a control rule for determining the opening degree of α, which is shown in Table 1 below.

[0019]

[Table 1]

In this table, S, M, and B indicate the degree of supercooling degree SC in three stages, which are respectively small, medium, and large cooling degrees. The target opening degree F of the expansion valve 17α is set like S ₂ , S ₁ and S ₂ as in the above language rule.

The above language rules are stored in the memory device 25 of FIG. 1 as three control rules as described below.

Rule R1: IF SC IS S THEN F = S ₂ Rule R2: IF SC IS M THEN F = S ₁ Rule R3: IF SC IS B THEN F = S ₁ Next, in the fuzzy inference means 26, Thus, the control rule stored in the memory device 25 is read and fuzzy inference is performed to calculate the opening degree of the indoor electric expansion valve 17α.

Each of the control rules R1, R2 and R3 described above determines the opening degree of the indoor electric expansion valve 17α with respect to the degree of supercooling SC in a stepwise manner. It is necessary to calculate the degree to which the condition section (IF section) is satisfied and to determine the opening degree of the indoor electric expansion valve 17α according to the degree.

In this embodiment, the membership function of the fuzzy variable is used to calculate the degree of satisfaction of the antecedent part (IF part).

FIG. 2 shows membership functions μS (SC) and μM (S) of fuzzy variables S, M and B with respect to the degree of supercooling SC.
C) and μB (SC), which are fuzzy inference means 26
The fuzzy inference executed by the control rule R1,
The opening degree of the indoor electric expansion valve 17α is calculated using R2, R3 and the membership function of FIG.

FIG. 3 is a flow chart (a) showing the procedure for calculating the opening degree of the indoor electric expansion valve 17α, and an explanatory auxiliary diagram (b) thereof.

To calculate the opening degree of the indoor electric expansion valve 17α, first in step 1, a deviation between the detected temperature output by the room temperature detecting means 19α and the target temperature set by the temperature setting means 20α is obtained, and the deviation is calculated from the deviation. The first target opening degree calculation means 22 calculates the first target opening degree S ₁ . Next step 2
Then, the supercooling degree SC detected by the supercooling degree detecting means 18α
Then, the second target opening degree calculation unit 23 calculates the second target opening degree S ₂ . In step 3, the fuzzy inference means 26 uses the membership function of the fuzzy variable for the supercooling degree SC to calculate the membership value at the supercooling degree SC. Next, in step 4, the degree to which the membership value obtained in step 3 belongs to the antecedent part (IF part) of each of the control rules R1, R2, and R3 is calculated, and based on the calculated degree of membership By the opening degree determination means 27, the first
The opening degree is determined from the mixture ratio of the target opening degree S ₁ of the second target opening degree S ₂ and the second target opening degree S ₂ and the opening side control means 28 controls the indoor side electric expansion valve.
It controls the valve opening of 17α.

In this valve opening control, as shown in FIG. 3 (b), for example, when the supercooling degree SC is SC1, it belongs to the control rules R2 and R3 by 50%.
The required opening F is calculated by the following equation (1).

[0029]

[Equation 1]

The present invention has been described above with reference to one embodiment. However, when the degree of supercooling SC is appropriate, the present invention uses the deviation between the room temperature and the target temperature as a control parameter to control the indoor electric expansion according to the air conditioning load. Optimal opening control of valve 17α,
If the degree of supercooling SC is too large or too small, the degree of supercooling S
By using C as a control parameter, the indoor electric expansion valve can be properly
By controlling the opening of 17α and performing fuzzy inference when the degree of supercooling SC is appropriate, or when the degree of supercooling is too large or too small, fine and smooth opening control is possible, and the control rule is Since the empirical rule is used, each indoor expansion valve 17α can be optimally controlled, and the capacity of each indoor unit can be equalized.

[0031]

As described above, in the heating control device for a multi-room air conditioner according to the present invention, when the degree of supercooling SC is a proper parameter, the control parameter for determining the opening of the indoor electric expansion valve is used. , The deviation between the room temperature and the target temperature, the degree of supercooling SC when the degree of supercooling SC is too large or too small, and when the degree of supercooling is too large or too small for the proper degree of supercooling SC Since the fuzzy inference of the opening degree is performed by the control rule based on the empirical rule, the opening degree of the indoor electric expansion valve can be finely and smoothly controlled.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of a heating control device for a multi-room air conditioner according to an embodiment of the present invention.

FIG. 2 is a characteristic diagram showing a membership function of a fuzzy variable with respect to a supercooling degree.

FIG. 3 is a flow chart showing a procedure of an opening degree calculation by fuzzy inference, and a characteristic diagram showing a degree of belonging of a fuzzy variable as an explanatory auxiliary diagram thereof.

FIG. 4 is a block diagram showing a configuration of a heating control device in an air conditioner using a conventional electric expansion valve.

[Explanation of symbols]

11 ... Outdoor unit, 12 ... Compressor, 13 ... Outdoor heat exchanger,
14 ... Outdoor electric expansion valve, 16α (α = a, b, c) ... Indoor unit, 17α (α = a, b, c) ... Indoor electric expansion valve, 18α
(α = a, b, c) ... Supercooling degree detection means, 19α (α =
a, b, c) ... Room temperature detecting means, 20α (α = a, b, c)
... temperature setting means, 21α (α = a, b, c) ... indoor heat exchanger, 22 ... first target opening calculation means, 23 ... second target opening calculation means, 24 ... microprocessor, 25 ... Memory device, 26 ... Fuzzy inference means, 27 ... Opening degree determination means,
28 ... Opening control means.

Claims (1)

[Claims] 1. A multi-room type air conditioner comprising an outdoor unit having an outdoor electric expansion valve and a plurality of indoor units having an indoor electric expansion valve connected in parallel with the outdoor unit, and a room temperature and a preset air conditioning temperature. A first target opening degree of the indoor electric expansion valve for controlling the air conditioning temperature according to the deviation of
The second target opening degree calculation means of the indoor electric expansion valve, which is calculated based on the degree of supercooling detected in the pipe portion between the indoor heat exchanger and the indoor electric expansion valve;
To obtain the optimum opening from the first and second target openings,
According to the control rule of the opening degree of the indoor electric expansion valve based on an empirical rule, a fuzzy inference means for performing a fuzzy logic operation is provided, and based on the result of the fuzzy inference,
A heating control device for a multi-room air conditioner, which is characterized by controlling the opening of an indoor electric expansion valve.