JP3515582B2 - Automotive air conditioner control device - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control device for an air conditioner for an automobile, and more particularly to a control device for an air conditioner, which has a hysteresis characteristic at a switching point of an outlet mode in fuzzy control. The present invention relates to a device capable of preventing a sense of discomfort when switching modes. 2. Description of the Related Art In recent years, air conditioners for automobiles have been designed to keep the interior of a vehicle always comfortable by means of information such as the outside air temperature, the amount of solar radiation, the temperature of the vehicle interior, and a temperature switch set to a desired temperature. 2. Description of the Related Art Auto air conditioners that automatically control blow temperature, blow air volume, switching of blow outlets, and the like have become widespread. And
Recently, a device has been devised that can perform warm-up and cool-down in a short time by using so-called fuzzy control, and can also easily perform a program setting and a change operation in a short time. . [0003] In the following, for example, an example in which fuzzy control is applied to control in an outlet mode will be described. First, as shown in FIG.
As in a general automobile air conditioner, an intake unit 1 for selectively taking in inside air or outside air, a cooling unit 2 for cooling intake air, and a conditioned air after adjusting the temperature of the intake air in the vehicle compartment. And a heater unit 3 that blows out. The intake unit 1 has a fan 5 rotated at a predetermined speed by a motor 4, and the cooling unit 2 has therein an evaporator 6 constituting a cooling cycle. [0004] A heater core 7 is provided in the heater unit 3, and a detour 9 is formed near the heater core 7 so that intake air bypasses the heater core 7 to reach the mixing chamber 8. An air mix door 10 for adjusting the ratio of the amount of air passing through the heater core 7 to the amount of air passing through the bypass 9 is provided rotatably on the upstream side of the heater core 7. This air mix door 10
As a result, the warm air heated through the heater core 7 and the unheated cool air passed through the bypass 9 flow down into the mixing chamber 8, where they are mixed and mixed to an appropriate temperature. After that, the differential air outlet 11 opened in the mixing chamber 8,
The air is supplied from one of the vent outlet 12 and the foot outlet 13 into the vehicle interior. Here, the differential outlet 11 is an outlet for guiding warm air to the inner surface of the windshield to remove fogging of the glass, and the vent outlet 12 blows out conditioned air to the upper body of the occupant to control the temperature in the room. Outlet for The foot outlet 13 is an outlet for mainly guiding warm air to the feet of the occupant to enhance the occupant's feeling of heating. A differential door 14, a vent door 15, and a foot door 16 are rotatably provided at these outlets 11 to 13, respectively. These three control doors 14 to 16 are connected to a mode such as an electric actuator via a link mechanism (not shown). The door is opened and closed by a door actuator 17. The outlet mode configured by combining the open / close positions of the three control doors 14 to 16 is, for example, a vent mode (VE) in which only the vent door 15 is opened.
NT mode), a foot mode (FOOT mode) in which the foot door 16 and the differential door 14 are each half-opened, and a bi-level mode (B / L mode) in which the vent door 15 and the foot door 16 are each half-opened. [0005] This air conditioner for automobiles detects a current opening degree of the air mix door 10 by, for example, PBR.
An air mix door position detector 18 is provided. The air mix door position detector 18 detects whether the air mix door 10 is currently located on the COOL side, the HOT side, or an intermediate position, and determines whether the air mix door 10 is at the middle position.
9 is output. On the other hand, although not shown, a fuzzy controller 19 includes an A / D converter for converting a position analog signal from the air mix door position detector 18 into a digital signal of 2 to 8 bits, and a membership for fuzzy inference. A ROM that stores functions, a fuzzy inference unit that stores fuzzy inference logic, and an arithmetic unit that calculates an operation position (voltage applied to the mode door actuator 17) and outputs the calculated position to the external signal conversion circuit 20 It is configured. The fuzzy controller 19 determines the operating position of the mode door actuator 17 by fuzzy inference in accordance with the control rules shown in FIG. 5, and the operation amount is determined by the control rules obtained from the control rules stored in the ROM in advance. This is executed according to the likelihood value (CF value). That is,
FIG. 5A shows a membership function relating to the antecedent variable, in which the horizontal axis represents the output voltage (PBR voltage) from the PBR, which is the air mix door position detector 18, and the CF corresponding thereto.
The values are shown on the vertical axis. At this time, when the CF value is represented by a fuzzy label, that is, a concept including ambiguity, when the PBR voltage is 2 V or more, “HOT side”, 1.7 to 2.5 V
Is "intermediate position", and 2V or less is "COOL side". On the other hand, FIG. 5C shows a membership function related to the consequent variable, in which the voltage applied to the mode door actuator 17 as the calculation result is shown on the horizontal axis, and the outlet mode is shown on the horizontal axis. FIG. 5B shows a fuzzy rule stored in advance in the fuzzy inference unit. If the PBR voltage is on the COOL side, the outlet mode is set to the vent mode, and if the PBR voltage is at the intermediate position, the blowing is performed. The exit mode is set to the bi-level mode, and if the PBR voltage is HO
If it is the T side, the outlet mode is set to the foot mode. The fuzzy controller 19 expresses the position data obtained by the air mix door position detector 18 with the membership function shown in FIG. 5A as an input condition in an ambiguous amount using the membership function. And
This is applied to the antecedent part of the fuzzy rule shown in FIG. 5 (b) to obtain the result of the consequent part, and the operation result expressed by the ambiguity is output using the membership function shown in FIG. 5 (c) as an output condition. Using the membership function, the mode door actuator is converted into an output value of the operating position. By such fuzzy inference, it is possible to perform smooth air outlet control generally similar to human feeling. However, in such a conventional fuzzy control, the PBR under the input condition is
When the voltage fluctuates, the air outlet fluctuates at the switching point of the air outlet mode under the output condition, and the occupant may feel uncomfortable. Further, at the switching point of the outlet mode, a malfunction may occur due to noise of the input signal. The present invention has been made in view of such problems of the prior art, and has a hysteresis characteristic at a switching point of an outlet mode in an outlet control by fuzzy control to prevent a sense of incongruity at the time of mode switching. It is an object of the present invention to provide a control device for an air conditioner for a vehicle which can be controlled. According to the present invention, there is provided an air mix door position detecting means for detecting a turning position of an air mix door for adjusting a mixing ratio of hot air and cold air. A mode door driving means for selecting an open / close position of a plurality of control doors provided at each of a plurality of outlets, and a detection signal from the air mix door position detection means, in accordance with a preset fuzzy control law. A control device for an air conditioner for a vehicle having fuzzy inference means for inferring an operation position of the mode door driving means, wherein an output signal from the fuzzy inference means is fed back to an input side, and the feedback signal and the air mix The outlet mode is set based on a detection signal from the door position detecting means and a preset fuzzy control law. When performing fuzzy control , the feedback signal
Using the membership function in the fuzzy control law
And express it as an ambiguous amount, and maintain the current outlet mode.
In the fuzzy control law provided to have
Apply the antecedent part of the fuzzy rule to maintain the current state
In the direction of the
Is controlled by fuzzy control . According to the present invention, the detection signal from the air mix door position detecting means, the feedback signal from the output side of the fuzzy inference means, and the fuzzy control preset in the fuzzy inference means are provided. The operating position of the mode door driving means is inferred based on the law. The fuzzy control rule has a fuzzy rule which is a set of rules defining a control method, and a membership function expressing an ambiguity. In the present invention, as the membership function, the first membership function for the detection signal from the air mix door position detecting means relating to the antecedent variable of the fuzzy rule and the fuzzy inference means relating to the consequent variable of the fuzzy rule are used. Three are set: a second membership function for the operation result and a third membership function for the feedback signal of the operation result of the fuzzy inference means relating to the antecedent variable of the fuzzy rule. The position data obtained by the air-mix door position detecting means is expressed in an ambiguous amount using the first membership function, and this is applied to the antecedent of the fuzzy rule to obtain the result of the consequent. The result expressed by the amount of ambiguity is converted into an output value of the operating position of the mode door driving means using the second membership function. At this time, the operation result, which is the output value of the fuzzy inference means, is returned to the input side and expressed in an ambiguous amount using the third membership function, and this is applied to the antecedent part of the fuzzy rule to apply the current outlet mode. Give the result of the consequent part to maintain the state. As described above, by feeding back the output of the fuzzy inference means to the input side, control is performed in a direction to maintain the current mode state. As a result, the switching point of the outlet mode has a hysteresis characteristic. Can be. An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing a control device of an air conditioner for a vehicle according to one embodiment of the present invention, and FIG. 2 is a diagram showing fuzzy control rules stored in a fuzzy controller of the embodiment. (a) and (b) show the membership function for the antecedent variable, (c) shows the fuzzy rule, and (d) shows the membership function for the consequent variable. FIG. 3 is a diagram showing a result of controlling the outlet according to the embodiment. In FIG. 1, the same members as those in FIG. 4 are denoted by the same reference numerals. This embodiment is a case where fuzzy control is applied to the control of the outlet mode. Since the configuration of the air conditioner for a vehicle shown in FIG. 1 is the same as that of the conventional example shown in FIG.
Here, only a brief description will be given. The main body of the vehicle air conditioner is composed of an intake unit 1, a cooling unit 2, and a heater unit 3. A fan 5 rotated by a motor 4 is provided in the intake unit 1, and an evaporator 6 is provided in the cooling unit 2. However, in the present invention, the cooling unit 2 is not essential, and the intake unit 1 and the heater unit 3 may be directly connected. The heater unit 3 has a heater core 7 therein. A detour 9 for intake air is formed near the heater core 7, and an air mixing door 10 is provided rotatably upstream of the heater core 7. A mixing chamber 8 is formed downstream of the heater core 7. The mixing chamber 8 is provided with a differential air outlet 11, a vent air outlet 12, and a foot air outlet 13.
13 to 13, a differential door 14, a vent door 15, and a foot door 16 are provided rotatably. These three control doors 14 to 16 are connected to a mode door actuator 17 such as an electric actuator via a link mechanism (not shown).
It is configured to be opened and closed by The outlet mode includes, for example, a vent mode (VENT mode) in which only the vent door 15 is opened, a foot door 16 and a differential door 1.
4 includes a foot mode (FOOT mode) in which the vent door 15 and the foot door 16 are each half-opened. It should be noted that such an outlet mode can be variously set without being limited to the present embodiment. Further, in this embodiment, there is provided an air mix door position detector 18 made of, for example, PBR or the like, which detects the current opening degree of the air mix door 10. The air mix door position detector 18 detects the current position of the air mix door 10 on the COOL side, the HOT side, or an intermediate position, and outputs it to the fuzzy controller 21. On the other hand, although not shown, the fuzzy controller 21 includes an A / D converter for converting a position analog signal from the air mix door position detector 18 into a digital signal of 2 to 8 bits, and a membership for fuzzy inference. A ROM that stores functions, a fuzzy inference unit that stores fuzzy inference logic, and an arithmetic unit that calculates an operation position (voltage applied to the mode door actuator 17) and outputs the calculated position to the external signal conversion circuit 20 It is configured.
In this embodiment, the signal on the output side of the fuzzy controller 21 is configured to be fed back to the input side. The fuzzy controller 21 determines the operating position of the mode door actuator by fuzzy inference according to the control rules shown in FIG. 2, and the operation amount is a certainty determined from each control rule stored in advance in the ROM. (CF value). That is, FIG. 2A shows a membership function related to the antecedent variable, and the horizontal axis represents the output voltage (PBR voltage) from the PBR, which is the air-mix door position detector 18, and the corresponding C
The F value is shown on the vertical axis. At this time, if the CF value is represented by a fuzzy label, that is, a concept including ambiguity, PBR
When the voltage is 2 V or more, “HOT side”, 1.7 to 2.5
V is the “intermediate position”, and 2 V or less is the “COOL side”. FIG. 2 (b) shows a membership function related to the antecedent variable, which is an operation result fed back from the output side of the fuzzy controller 21 (this is referred to as an input mode in the sense of an input mode, abbreviated as IMODE). )
The horizontal axis shows the voltage applied to the barrel mode door actuator 17, and the horizontal axis shows the CF value in the outlet mode corresponding to this. On the other hand, FIG. 2D shows a membership function relating to the consequent part variable, which is a calculation result output from the fuzzy controller 21 (the output result in the sense of the output mode).
The horizontal axis indicates the voltage applied to the mode door actuator 17 (MODE, abbreviated as OMODE), and the horizontal axis indicates the CF value of the outlet mode corresponding to this. Note that the output-side operation result (OMODE) and the input-side operation result (IMO)
DE) are the same. FIG. 2C shows fuzzy rules stored in the fuzzy inference unit in advance, and these control rules are qualitatively described in a language. That is, if the operation result (IMODE) is the vent mode, the outlet mode (OMODE) is set to the vent mode. Similarly, if the operation result (IMODE) is the bilevel mode, the outlet mode (OMODE) is set to the bilevel mode. If the operation result (IMODE) is the foot mode, the outlet mode (OMODE) is set to the foot mode. If the PBR voltage is on the COOL side, the outlet mode (OMODE) is set to the vent mode. If the PBR voltage is at the intermediate position, the outlet mode (OMODE) is set to the vent mode and the foot mode. If the PBR voltage is on the HOT side, the outlet mode (OMODE) is set to the foot mode. Then, the fuzzy controller 21 compares the membership functions shown in FIGS.
Fuzzy inference is performed with the fuzzy rules shown in (c). First, a membership function of the antecedent part is determined for each rule using the input value, that is, the PBR voltage and the calculation result. From this result, the form of the membership function in the consequent is modified. The output value used for the control is obtained by integrating the forms of the membership function obtained for each rule. The operation of obtaining this output value is called defuzzifier processing.The most commonly used method is to create a figure in which all the obtained membership function shapes of the consequent part are superimposed, and to set the horizontal axis coordinate of the position of the center of gravity. , And this is used as the output value of fuzzy inference. In this fuzzy inference, in the present embodiment, the calculation result (OMO) on the output side of the fuzzy controller 21 is used.
DE) is fed back to the input side and expressed in an ambiguous amount using the membership function shown in FIG. 2 (b), which is provided to maintain the current outlet mode as shown in FIG. 2 (c). By applying the rule to the antecedent part of the rule, the result of the consequent part is output in a direction to maintain the current state.
As a result, as shown in the control result of FIG. 3, hysteresis is formed at the switching point of the outlet mode. Therefore, even if the position of the PBR 18 fluctuates at the switching point of the outlet mode, the outlet does not change. Therefore, in the outlet control by the fuzzy control, the uncomfortable feeling of the occupant due to the fluctuation of the outlet is eliminated. Also, PBR
Malfunction due to voltage noise is also prevented. It should be noted that the concept of the present invention that the signal on the output side of the fuzzy controller 21 is fed back to the input side to provide a hysteresis characteristic at the switching point is only in the case of the control in the outlet mode as in this embodiment. And can be applied to all fuzzy controls. This allows
It is possible to eliminate a feeling of strangeness in control and prevent a malfunction due to noise of the input signal. Further, in the conventional method, the fuzzy control is applied only to a portion that is not so noticeable even if a malfunction occurs slightly. However, according to the concept of the present invention, the fuzzy control can be applied to all the portions that are originally desired to be switched. In addition to improved controllability, the program development time is shortened, and the program can be applied to almost all types of control, so that there is an effect that a degree of freedom can be obtained in the program. As described above, according to the present invention, in the control of the outlet mode by fuzzy control, the output of the fuzzy inference means is fed back to the input side to maintain the current mode state. Therefore, the switching point of the outlet mode can be provided with a hysteresis characteristic, and the occupant's discomfort at the mode switching point can be eliminated.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram showing a control device of an air conditioner for a vehicle according to one embodiment of the present invention. FIG. 2 is a diagram showing a fuzzy control law stored in a fuzzy controller of the embodiment, wherein FIG.
(b) is a diagram showing the membership function related to the antecedent variable,
FIG. 13C shows a fuzzy rule, and FIG. 14D shows a membership function related to the consequent variable. FIG. 3 is a view showing an outlet control characteristic according to the embodiment. FIG. 4 is a block diagram showing a control device of a conventional air conditioner for a vehicle. 5A and 5B are diagrams showing fuzzy control rules stored in the fuzzy controller of FIG. 4, wherein FIG. 5A shows a membership function relating to antecedent variables, and FIG. 5B shows a fuzzy rule. And (c) is a diagram showing a membership function related to the consequent variable. DESCRIPTION OF SYMBOLS 10 ... Air mix door 11 ... Differential outlet 12 ... Vent outlet 13 ... Foot outlet 14 ... Differential door 15 ... Vent door 16 ... Foot door 17 ... Mode door actuator (mode door driving means) 18 ... PBR (Air Mixed door position detecting means) 21 ... Fuzzy controller (Fuzzy inference means)

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int.Cl. ⁷ , DB name) B60H 1/00

Claims (1)

(57) Claims: 1. An air mix door position detecting means (18) for detecting a turning position of an air mix door (10) for adjusting a mixing ratio of hot air and cold air; A mode door driving means (17) for selecting an open / close position of a plurality of control doors (14, 15, 16) provided in each of the air outlets (11, 12, 13); and an air mix door position detecting means (18). A) a fuzzy inference means (21) for inferring the operating position of the mode door drive means (17) according to a preset fuzzy control law using the detection signal from It is fed back to the input side of the output signal from said fuzzy inference means (21), the detection signal from the feedback signal, the air mixing door position detection means (18) , Upon which the fuzzy control outlet mode on the basis of the preset fuzzy control rule, the feed
The back signal is used for the membership in the fuzzy control law.
Is expressed as an ambiguous quantity using the
The fuzzy system provided to maintain the mouth mode
Applied to the antecedent part of fuzzy rules in rules
Try to keep a certain condition,
A control device for an air conditioner for a vehicle, characterized in that the outlet mode is fuzzy controlled .