JPH07101121B2 - Air conditioner control system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of Industrial Application The present invention relates to an air conditioner control system using fuzzy inference to control the operating capacity of a compressor, and particularly to fuzzy inference during cooling operation and heating operation. It is about fuzzy reasoning.

(B) Prior Art Generally, a conventional fuzzy control device is disclosed in JP-A-1-1429.
There was something like that described in the 02 publication. What is described in this publication is, "In a fuzzy control system of an automobile, which includes a fuzzy control unit for performing fuzzy control of a controlled object such as a propulsion device of the automobile by a processor mounted on the automobile, a storage device is provided in the fuzzy control unit. And a read control unit of the storage control device, the detection amount and temporal change in the controlled object unit are calculated in advance in the storage device according to a predetermined rule, and the result is stored as a table. Read control section reads the table at a predetermined time to control the controlled section.

By configuring the fuzzy controller in this way,
When the processor is provided with a detection value, the fuzzy control can be performed only by reading the value corresponding to the detection value from the table. That is, the processor does not need to perform fuzzy inference that takes a long processing time for each detected value, and has an advantage that the processing time for fuzzy control in the processor can be shortened.

(C) Problems to be Solved by the Invention In the conventional technology configured as described above, the processing time of the processor can be shortened by using the table. However, this table can be used for a specific controlled object part. It was made in advance. Therefore, there is a problem that the same fuzzy inference is always applied even when the controlled object has a plurality of operating states. For example, when the controlled object is an air conditioner, in general, the user's perception of the room temperature is different between the cooling operation and the heating operation, and when fuzzy inference having only the single characteristic is used, The control suitable for each operating condition cannot be performed sufficiently.

With respect to such a problem, the present invention changes the characteristics of fuzzy inference according to the operating state of the controlled object, and provides an air conditioner configured to perform optimum fuzzy control in accordance with each operating state. It provides a control method.

(D) Means for Solving the Problems The present invention relates to fuzzy control used for operation control of an air conditioner, in which the fuzzy control obtains the degree of establishment of the membership function of the antecedent part based on the room temperature. The membership function of the department is applied to the control rule to weight the membership function of the consequent part, and the control output is obtained according to the weighting of the membership function of the consequent part. Besides, the membership function of the antecedent part and / or the consequent part is changed during the cooling operation and the heating operation of the air conditioner.

When the air conditioner is in cooling operation, some of the membership functions of the antecedent part and / or the consequent part are shifted in the direction in which the control output is decreased, or
And some of the membership functions of the consequent part are changed from the form of the membership function of the antecedent part and / or the consequent part during the heating operation in the direction in which the control output is decreased.

Further, the fuzzy control obtains the degree of satisfaction of the membership function of the antecedent part based on the room temperature, and applies the degree of satisfaction of the membership function of the antecedent part to the control rule to determine the membership function of the consequent part. Weighting is performed, and the consequent part is configured to obtain a control output according to the weighting level of the membership function, and a part of the control rule is changed during cooling operation and heating operation of the air conditioner. It will be.

(E) Operation By using the air conditioner control system configured in this way, the characteristics of fuzzy inference can be changed according to the operating conditions of the air conditioner.

(F) Embodiments Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic diagram when the fuzzy control device is applied to temperature control of a conditioned room. In the figure, 1 is a temperature-controlled room, 2 is an air-conditioning unit that is provided in the room and is capable of cooling and heating operations, and discharges cooling air or heating air from a discharge port. The air-conditioned room is cooled or heated. This air conditioning unit can change the cooling capacity or the heating capacity by using an inverter device described later. Reference numeral 3 is a temperature sensor attached so as to detect the room temperature of the room to be conditioned 1, and uses a detection element such as a thermistor whose internal resistance value changes with temperature. A room temperature setting device 4 outputs a signal corresponding to the set temperature. As this room temperature setting device, there are various ones such as one that changes a resistance value by using a variable resistor, one that changes an output voltage by using a voltage generator, and one that outputs a code or a signal having a value corresponding to the set value. Can be used. Reference numeral 5 denotes a detection value output unit, which calculates a corresponding room temperature T from a change in the internal resistance value of the temperature sensor 3, and a difference "e = T-" between the room temperature T and the room temperature S set in the room temperature setting device 4. S "is calculated (note that when heating operation is performed," e =-(T-S) ". The difference between the previously obtained difference e'and the presently obtained difference e" Δe = e '"
-E "is calculated, and the difference e and Δe are output to the microcomputer computer 6. The microcomputer 6 calculates the output using the difference e, Δe and outputs it to the inverter device 11. The inverter device 11 variably controls the operating capacity of the air conditioning unit 2 based on a signal given from the microcomputer 6. For example,
When a compressor using an induction motor as a drive source is used for the air conditioning unit 2, the operating capacity of the air conditioning unit 2 can be changed by changing the frequency of the AC power supplied to this induction motor. As another method, when a compressor using a DC electric motor as a drive source is used, the operating capacity of the air conditioning unit 2 can be changed by changing the voltage of DC electric power supplied to this DC electric motor. Incidentally, 7-
Reference numeral 10 denotes a storage unit, and in the present embodiment, one storage element is divided and a plurality of areas are set and distributed to the storage units 7 to 10.

The operation of the microcomputer 6 will be described below. The microcomputer 6 performs fuzzy inference using the above e and Δe. Fig. 2 shows an example of a membership function (isosceles triangle). Set this membership function as a function that gives the values of A and C on the horizontal axis and the maximum satisfaction degree B on the vertical axis. You can
That is, when (1) e <A, the degree of satisfaction of the membership function is 0, and when (2) A ≦ e <(A + C) / 2, the degree of satisfaction of the membership function is (2B × (e−A)) / (C −
A), (3) (A + C) / 2 ≦ e <C, the degree of satisfaction of the membership function is − (2B × (e−C)) / (C−
In A) and (4) C ≦ e, the degree of establishment of the membership function is 0. In this way, if the constants A, B, and C shown in FIG. 2 are set, the function representing this membership function can be set. Therefore, if the value of e is obtained, the degree of establishment of the membership function can be obtained. still,
Membership functions are not limited to isosceles triangles, but are equilateral triangles, trapezoids, bells, and other controlled objects and users
It may be set arbitrarily based on the feeling, but it is preferable that it is a form that can be easily made into a function.

FIG. 3 is a characteristic diagram showing the membership function of the antecedent portion with respect to the difference e between the room temperature and the set value in the cooling operation mode. The membership functions NB, NS, Z0, PS, and PB are set to constants corresponding to A, B, and C in FIG. 2, and the functions that represent the membership functions are set from these constants. There is. A list of constants representing these functions is shown in FIG. It should be noted that the membership function Z0 represents a set in which there is no difference e, the membership function PS represents a set in which the difference e is slightly on the plus side, and the membership function PB indicates that the difference e is large on the plus side. The membership function NS represents a set in which the difference e is slightly on the negative side, and the membership function NB is a set in which the difference e is large on the negative side. FIG. 3 is a membership function of the antecedent part in the heating operation mode, and a list of constants is shown in FIG. 5 at the same time as the membership function shown in FIG.

Therefore, the degree of establishment of each of the membership functions of the antecedent part with respect to the difference e can be calculated from the above formula using the constants of the cooling operation mode or the heating operation mode for each of the membership functions NB to PB. it can.

Although the membership function of the antecedent part shown in FIGS. 3 and 4 is changed in both shape and arrangement, only one of them may be changed.

Similarly, for the rate of change Δe of the difference e, the membership function of the antecedent part can be set. In this case, the constant of the function representing the membership function may be changed between the cooling operation mode and the heating operation mode, or the same constant may be used. Generally, when the change width of Δe is set to be large, it is preferable to change the constant between the cooling operation mode and the heating operation mode. When the change width of Δe is small, the same constant can be used, but the invention is not limited to this. In addition, Δ
As for the membership function for e, five kinds of membership functions from NB to PB are set similarly to the membership function for e.

Figure 6 is a relational diagram of tuning for weighting the membership function of the consequent part (rules used for fuzzy inference)
And the degree of satisfaction of the membership function with respect to e and Δ
The membership function of the consequent part is weighted based on the degree of establishment of the membership function for e.
The membership function of the consequent part sets seven functions NB to PB. The membership function Z0 represents a set that does not change the operating capacity of the air conditioning unit 2 shown in FIG. 1, the membership function PS represents a set that slightly increases the operating capacity of the air conditioning unit 2, and the membership function PM represents the membership function PM. The membership function PB represents a set that significantly increases the operating capacity of the air conditioning unit 2, and the membership function NS
Represents a set that slightly reduces the operating capacity of the air conditioning unit 2, the membership function NM represents a set that reduces the operating capacity of the air conditioning unit 2 to a medium level, and the membership function NB significantly reduces the operating capacity of the air conditioning unit 2. Represents a set. The horizontal axis of these membership functions sets the amount of increase or decrease in the operating capacity of the air conditioning unit 2. The following 17 rules are set as fuzzy reasoning rules.

(1) Membership function NB for e is established and Δ
If the membership function NB for e is established, the membership function NB of the consequent part is established.

(2) Membership function NS for e is established and Δ
If the membership function NS regarding e is established, the membership function NM of the consequent part is established.

:: (17) Membership function PB for e holds and Δ
If the membership function PB relating to e is established, the membership function PB of the consequent part is established.

FIG. 7 is a tuning relationship diagram showing other characteristics,
When the relationship shown in FIG. 6 is the heating operation, the relationship shown in FIG. 7 shows the cooling operation. In this figure, the difference from the relationship diagram shown in FIG. 6 is that if the membership function NS regarding e is satisfied and the membership function NS regarding Δe is satisfied, the membership function of the consequent part is the same as the above-mentioned rule (1). NS is established ", when the membership function PB for e is established and the membership function Z0 for Δe is established, and when the membership function Z0 for e is established and the membership function PB for Δe is established. The point is that the rule of time was deleted. By changing the tuning relationship in this way, the weighting of the membership function NS in the consequent part as well as the weighting of the membership function NS is reduced, and fuzzy inference tends to not increase the operating capacity of the air conditioner as a whole. The characteristics of will change.

FIG. 8 is a characteristic diagram of the membership function of the consequent part weighted by the tuning relation diagram of FIG. 6 or 7. In this figure, the horizontal axis represents the output, that is, the increase / decrease value of the operating capacity of the air conditioning unit 2. The functions representing the membership functions NB to PB of the consequent part are determined in the same manner as the membership function of the antecedent part if the three constants A, B and C are determined. Among the constants, A and C are preset from the membership function of the consequent part shown in FIG. Similar to the membership function of the antecedent part, these constants may store two types of constants of the cooling operation mode and the heating operation mode, and may be selected and used according to the operation state of the air conditioning unit. The constant B represents a weight value and is a value set by the above rules (1) to (17).

In this figure, the membership function represented by the constants A = f2 ', B = y13', C = f4 '(the membership function along the dotted line) is a function that replaces the membership function NS during cooling operation. NS has moved to the left.

FIG. 9 is an explanatory diagram showing the values of the constants A and C of the membership function of the consequent part. As the constant B, a value weighted by a tuning relationship diagram is used. As the constant of the membership function NS, the value of the constant used in the cooling operation mode and the value used in the heating operation mode are different. That is, the left side (A = f2, C = F4) of the membership function NS column in FIG. 9 is a constant used in the heating operation mode, and the right side (A = f2 ', C = f4') is used in the cooling operation mode. It is a constant.

Next, the main operation of the microcomputer 6 will be described with reference to the flowchart of FIG. First, fuzzy inference is started from step S0. This fuzzy inference is performed every predetermined period (once every 30 seconds) as part of the control of the air conditioning unit. Therefore, the operation capacity of the air conditioning unit is changed every predetermined period. Next, in step S1, it is determined whether or not the cooling operation is performed. That is, it is determined whether to use the data of the cooling operation mode or the data of the heating operation mode. The distinction between the cooling operation mode and the heating operation mode is not limited to whether the air conditioning unit is set to the cooling operation / heating operation, and a seasonal change may be incorporated in the switching element. Needless to say, the number of modes may be two or more in addition to the intermediate mode. Next, in steps S2 and S3, the data corresponding to the mode is read from the storage unit. In step S2, the constants for the cooling operation shown in FIG. 5, the data showing the tuning relationship on the cooling operation side shown in FIG. 7, and the constants for the cooling operation shown in FIG. 9 are read from the storage unit. The function that represents the membership function is set. Similarly, in step S3, the constant for heating operation is read from the storage unit to set the function for heating operation.

Next, in step S4, the values of e and Δe are input, and then step S5
Calculate the degree of establishment of each membership function.
For example, when e = e1 and Δe = Δe1 in the cooling operation mode, e1 and Δ are respectively added to the function (the function using the data in the cooling operation mode) representing the membership function of the antecedent part described above.
By substituting e1, for e, as shown in FIG. 11, the degree of satisfaction of the membership function Z0 becomes E2, and the degree of satisfaction of the membership function PS becomes E1.
The degree of establishment of PB is 0. Regarding Δe, as shown in FIG. 12, the degree of satisfaction of the membership function Z0 is ΔE2, the degree of satisfaction of the membership function PS is ΔE1, and the degree of satisfaction of the membership functions NB, NS, PB is 0.

Next, in step S6, the membership functions NB to PB of the consequent part are weighted. The membership functions for which the antecedent part holds from FIGS. 11 and 12 are the membership function Z0 and the membership function PS for e, and the membership function Z0 and the membership function PS for Δe. . Therefore, the rule of the shaded part as shown in FIG. 13 is applied. This rule is the rule described with reference to FIG. That is, in the consequent part, membership function Z0, membership function PS, membership function
PM is approved. The respective weighting values are E2 × ΔE2, E1 × ΔE2
(E1 × ΔE2 <E2 × ΔE1 is used for E1 × ΔE2), E1
× ΔE1.

In this embodiment, the degree of establishment of the membership function of the antecedent part is represented by byte data of 0 to FF (hexadecimal system), and the weighting of the membership function of the consequent part is 0 to FFFF (hexadecimal system).
However, the degree of establishment and the weighting may be converted into a value of 0 to 1 for handling. At this time, the constant y stored in the storage unit is set to a value of 0 to 1.

In this way, the weighting value of the membership function of the consequent part thus obtained is taken as the constant B of this membership function, and the respective membership functions are synthesized using the constants A and C shown in FIG. A synthetic figure as shown in FIG. 14 is obtained.

Next, in step S7, the center of gravity of the composite figure shown in FIG. 14 is calculated. The center of gravity is the constant A, B of the membership function before composition.
(Weighting value), C is used to calculate. The calculated center of gravity is G. Then, in step S8, the value Δf1 on the horizontal axis corresponding to the center of gravity is obtained. This Δf1 is output to the inverter device 11 as the amount of change in the capacity of the air conditioning unit. When the frequency of the AC power supply that supplies the operating capacity of the air conditioning unit 2 is changed, Δf1 corresponds to the increase / decrease value of the frequency.

In addition, since the constants and rules for the heating operation are set in step S3 during the heating operation, e = e1, Δ
Even if the detected value is e = Δe1 and is the same value as during the cooling operation, the degree of establishment of the membership function PS of the antecedent shown in FIG. 4 becomes large. Therefore, the final (the increase / decrease value of the operating capacity of the air conditioning unit) becomes larger on the positive side than in the cooling operation.

In this way, the characteristics of the fuzzy evolution theory are changed between the cooling operation and the heating operation, so that even if the same detection value is input, the magnitude of the output changes between the cooling operation and the heating operation. Therefore, fuzzy inference can be set during cooling operation so that it is suitable for cooling operation, and fuzzy inference can be set during heating operation that is suitable for heating operation. It is capable of fuzzy reasoning.

(G) Effect of the Invention As described above, in the present invention, in the fuzzy control used for the operation control of the air conditioner, the fuzzy control obtains the degree of establishment of the membership function of the antecedent part based on the room temperature. Applying the degree of establishment of the membership function of the above to the control rule to weight the membership function of the consequent part,
The control output is obtained according to the weighting of the membership function of the consequent part, and the membership of the antecedent part and / or the consequent part during the cooling operation and the heating operation of the air conditioner. Since the arrangement or shape of the function or the control rule is changed, the characteristics of fuzzy inference can be changed between the cooling operation and the heating operation of the air conditioner. Therefore, it is possible to set the fuzzy inference suitable for each of the cooling operation and the heating operation, perform the optimum fuzzy inference regardless of the cooling operation and the heating operation, and improve the comfort of the controlled room.

[Brief description of drawings]

FIG. 1 is a schematic diagram showing an outline of the present invention, FIG. 2 is a characteristic diagram showing an example of a membership function (isosceles triangle), and FIG.
Cormorant is a characteristic diagram of the membership function in the antecedent part of the cooling operation mode, Fig. 4 is a characteristic diagram of the membership function in the antecedent part of the heating operation mode, and Fig. 5 is before use in the cooling operation mode and the heating operation mode. Correspondence diagram of the constants of the function representing the membership function of the condition part, Fig. 6 is a related diagram when weighting the membership function of the condition part, and Fig. 7 is the membership of the condition part used in the cooling operation mode. Relationship diagram when weighting functions, Fig. 8 is a characteristic diagram of membership function of consequent part, Fig. 9 is a correspondence diagram of constants of membership function of consequent part, and Fig. 10 is micro. Fig. 11 is a flowchart showing the operation of fuzzy control by a computer.
= E1, an explanatory diagram showing the degree of satisfaction of the antecedent part, Fig. 12 is an explanatory diagram showing the degree of satisfaction of the antecedent part when Δe = Δe1, and Fig. 13 when e = e1, Δe = Δe1. FIG. 14 is an explanatory view showing a membership function for weighting, and FIG. 14 is a diagram of a figure obtained by combining the membership functions of the consequent part weighted by FIG. 1 ... Conditioned room, 2 ... Air conditioning unit, 3 ... Temperature sensor, 4 ... Room temperature setting device, 5 ... Output unit, 6 ... Microcomputer, 7-10 ... Storage unit, 11 ... Inverter device .

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yoshitaka Hara 2-18 Keihan Hondori, Moriguchi City, Osaka Sanyo Electric Co., Ltd. (72) Kazuhito Fujinaka 2-18 Keihan Hondori, Moriguchi City, Osaka Sanyo Electric Machinery Co., Ltd. (56) Reference JP 63-131942 (JP, A) JP 56-110859 (JP, A)

Claims (4)

[Claims] 1. A refrigeration cycle is constructed using a compressor, a condenser, a decompression device, and an evaporator whose operation capacity can be arbitrarily changed.
When controlling the operating capacity of the compressor of the air conditioner configured to perform the air conditioning operation of the controlled room by changing the operating capacity of the compressor based on the difference between the room temperature and the set temperature of the controlled room,
In the control method using the fuzzy control, which detects the room temperature of the room to be conditioned, and applies the detected value to the control rule based on the empirical rule, the fuzzy control is based on the detected value of the room temperature and the membership function of the antecedent part. Of the membership function of the antecedent part is applied to the control rule to weight the membership function of the antecedent part, and the weighting degree of the membership function of the antecedent part is calculated. The control function of the air conditioner is characterized in that the membership function of the antecedent part and / or the consequent part is changed during the cooling operation and the heating operation of the air conditioner. method. 2. When the air conditioner is in a cooling operation, some of the membership functions of the antecedent part and / or the consequent part are shifted in a direction in which the control output is decreased. The control system for the air conditioner according to item 1. 3. The membership function of the antecedent part and / or the consequent part during the heating operation when some forms of the membership function of the antecedent part and / or the consequent part are used when the air conditioner is in the cooling operation. The control method of the air conditioner according to claim 1, wherein the control output is changed in the direction in which the control output is decreased. 4. A refrigeration cycle is configured by using a compressor, a condenser, a pressure reducing device, and an evaporator whose operation capacity can be arbitrarily changed,
When controlling the operating capacity of the compressor of the air conditioner configured to perform the air conditioning operation of the controlled room by changing the operating capacity of the compressor based on the difference between the room temperature and the set temperature of the controlled room,
In the control method using the fuzzy control, which detects the room temperature of the room to be conditioned, and applies the detected value to the control rule based on the empirical rule, the fuzzy control is based on the detected value of the room temperature and the membership function of the antecedent part. Of the membership function of the antecedent part is applied to the control rule to weight the membership function of the antecedent part, and the weighting degree of the membership function of the antecedent part is calculated. A control method for an air conditioner, characterized in that a part of the control rule is changed during cooling operation and heating operation of the air conditioner.