JP3333218B2 - Vehicle 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 vehicle for processing a plurality of physical quantities relating to a heat load required for air conditioning, such as an outside air temperature and an amount of solar radiation, in accordance with a system control theory (modern control theory) to air-condition a vehicle interior to a target temperature. The present invention relates to an air conditioner.

[0002]

2. Description of the Related Art Conventionally, a vehicle air conditioner for controlling the air volume and an air outlet based on a vehicle interior temperature set value, an actual vehicle interior temperature, an outside air temperature and an amount of solar radiation to air the vehicle interior to a target temperature. (For example, see Nissan Service Newsletter, No. 578, June 1987). In this type of device, as shown in FIG. 10, the vehicle interior temperature set value Tptc,
Vehicle interior temperature Tinc, solar radiation Qsun and outside air temperature T
amb is input to the controller 1, and the difference between the set temperature Tptc and the actual vehicle compartment temperature Tinc, the amount of solar radiation Qsun, the outside air temperature Tamb, and the set temperature Tptc are multiplied by experimentally obtained control constants K10 to K13, respectively. The control command value is calculated, and the control amounts of the air conditioning unit 2, that is, the air mixing door opening X and the blower driving voltage Vf are determined by the computing units 1a and 1b. The air conditioning of the passenger compartment 3 is performed by controlling the well-known air-conditioning unit 2 comprising the target air temperature To and the target air volume Ga.

[0003]

However, in the conventional apparatus, in order to determine a control constant of a controller satisfying responsiveness and stability under any environmental conditions,
In addition to requiring a large number of experimental man-hours, there is a problem that the comfort of the occupant is not satisfied in an environment other than the environmental conditions assumed in advance.

An object of the present invention is to provide an air conditioner for a vehicle which follows a target value while ensuring responsiveness and stability under all environmental conditions, and can easily tune a control constant.

[0005]

Means for Solving the Problems The present invention will be described with reference to FIG. 1 which is a claim correspondence diagram.
Adjusting means 2 for adjusting the temperature and air volume of the conditioned air blown into the interior
And vehicle interior temperature detecting means 100 for detecting the vehicle interior temperature
And a mathematical model of the control targets 2 and 3 previously identified as the control targets 2 and 3 which output the vehicle interior temperature by inputting the control amount of the adjusting means 2 and feed back the occupant's skin temperature as a state variable. A skin temperature estimating means 72 having a formalized model for feeding back the deviation between the output of the formalized model and the detected value of the vehicle interior temperature, and using the skin temperature of the state variable of the formalized model as an estimated skin temperature; A target value generation means 71 for generating a target value to be temporally changed between the room temperature and the occupant skin temperature, and the detected vehicle interior temperature value and the estimated skin temperature value are matched with the target vehicle interior temperature value and the target skin temperature value, respectively. By calculating a control amount of the adjusting means 2 for causing the control means 74 to control the adjusting means 2,
The above object is achieved.

[0006]

A control system which feeds back a mathematical model of the controlled objects 2 and 3 which receives a control amount of the control means 2 and outputs a vehicle interior temperature as a state variable, and a control system which feeds back an occupant's skin temperature as a state variable; A control system that feeds back a deviation from the vehicle interior temperature detection value is constructed,
In advance. That is, when the same control amount is input to the actual control targets 2 and 3 and the mathematical model, coefficients and parameters are set so that the skin temperature of each state variable and the vehicle interior temperature of the output become the same. Accordingly, when the same control amount as that of the controlled objects 2 and 3 is input to the mathematical model, the mathematical model performs the same operation as the controlled objects 2 and 3,
The state variables of skin temperature in the mathematical model are also controlled
At the same time as the actual occupant skin temperature. Therefore, the skin temperature of the state variable in the mathematical model is used as an estimated skin temperature, and a target value that is to be changed over time between the vehicle interior temperature and the occupant's skin temperature is generated. The control amount of the adjusting means 2 for making the estimated values coincide with the target values is calculated, and the temperature and the amount of the conditioned air blown into the vehicle interior 3 are adjusted.

In the means and means for solving the above-mentioned problems which explain the constitution of the present invention, the same reference numerals as those of the embodiment corresponding to the reference numerals of the respective means are used to make the present invention easy to understand. Although used, the present invention is not limited to the examples.

[0008]

FIG. 2 is a block diagram showing the configuration of one embodiment. It is to be noted that the same reference numerals are given to the same devices as those in FIG. In the figure, 4 is a solar radiation sensor for detecting the amount of solar radiation Qsun, and 5 is an outside air temperature Ta.
An outside air temperature sensor 6 for detecting mb is a room temperature setting device for setting a vehicle interior temperature set value Tptc.

Reference numeral 7 denotes a controller comprising a microcomputer and its peripheral parts, which comprises a reference model 71, an observer 72, a linear compensator 73, and an optimum regulator 74, and has a solar radiation Qsun, an outside air temperature Ta.
mb, vehicle interior temperature set value Tptc and vehicle interior temperature Ti
Based on nc, a control amount, that is, an air mix door opening X and a blower driving voltage Vf are calculated, and the air conditioning unit 2 is controlled.

The normative model 71 formulates the time-dependent change of the blow-off air volume Ga and the blow-off temperature To and the environmental change in accordance with human comfort as shown in the following equation, and changes the vehicle interior temperature set value Tptc. Target skin temperature Tf ^*
And the target vehicle interior temperature Tinc ^* is calculated. These target skin temperature Tf ^* and target vehicle interior temperature Tinc ^* are
The purpose of the present invention is to determine a comfortable air-conditioning temperature at a regular time and at the same time, to determine a degree of change in the temperature suitable for the occupant's feeling of comfort even during a transition until reaching the target temperature. dXr / dt = Ar · Xr + Br · Tptc (1) Yr = Cr · Xr (2) where Xr is a state variable vector, Yr is an output variable vector, and Xr = Yr = [Tf ^* , Tinc ^* ] ^T , and Ar, Br, and Cr are coefficient matrices.

FIG. 3 is a time chart showing the air conditioning result (solid line) by the vehicle air conditioner according to the present invention and the air conditioning result (broken line) by the conventional device.
Shows the time when the set temperature Tptc is lowered, and FIG.
2 shows when the set temperature Tptc is increased. In the conventional air conditioner, the transient change of the vehicle interior temperature Tinc when the set temperature Tptc is changed is determined by the control amount of the controller 1, and the transient state does not always satisfy the comfort of the occupant. In the air conditioner of the present invention, the target skin temperature Tf ^* and the target vehicle interior temperature Tinc ^* according to the time change and the environmental change are determined in the reference model 71. The air conditioning temperature that suits the feeling is set.

FIG. 4 is a control block diagram showing the structure of the observer 72. In the following, symbols and the like in the control block diagram are displayed according to a general notation of system control (modern control), and description thereof will be omitted. In the figure, reference numeral 72a denotes an actual control target system, and fixed coefficient matrices Ao, Bo,
Linear time-invariant system with Co (fixed coefficient system)
It is assumed that The observer 72 has an estimated model of the control target system 72a identified in advance, and a deviation between the measurable interior temperature Yo (= Tinc) and the estimated interior temperature Yo ^S output from the identified model ( by feeding back the Yo-Yo ^S),
The vehicle temperature Tm, which cannot be measured or is difficult to measure as shown in FIG.
The blowout air amount Ga, the air mix door opening Xmm (not shown), and the like are estimated, and the current skin temperature Tf is estimated based on these estimated values.

Now, the state process of the system 72a to be controlled will be described.
Expressions and output expressions are expressed as follows. dXo / dt = Ao · Xo + Bo · U (3) Yo = Tinc = Co · Xo (4) where Xo is a state variable vector, and Xo = [Tm, Tinc, Ga, Xmm]^T U is a control command value vector. Identified in advance
Body temperature Tm and blown air volume G estimated by the constant model
a and the state variable Xo of the air mix door opening Xmm
Xo^SThen, the estimation model is expressed by the following equation.
Is done. dXo^S/ Dt = Ao ・ Xo^S+ Bo · U (5) Yo = Tinc^S＝ Co ・ Xo^S ... (6) where Xo^S= [Tm^S, Tinc^S, Ga^S, Xm
m^S]^T, Tm^SIs the estimated value of the vehicle body temperature Tm, Tinc^SIs a car
Estimated value of room temperature Tinc, Ga S is the blowing air volume Ga
Estimated value, Xmm^SEstimates Amix door opening Xmm
Value. For fluctuation of coefficient matrix Ao, Bo and disturbance
Error eo (= Xo)^S-X
In order to make o) converge to 0, as shown in FIG.
By adding the back to the estimation model, observer 7
2 is expressed as follows. dXo^S/ Dt = Ao ・ Xo^S+ Bo ・ U + F ・ (Yo-Yo^S(7) where F is a feedback coefficient matrix.

Incidentally, the system to be controlled in the air conditioner is non-linear, and it is difficult to make the optimum regulator 74 described later to operate non-linearly. Therefore, linearization compensation is performed by the linear compensator 73. The linear compensator 73 corresponds to FIG.
As shown in (a), it is constituted by nonlinear state feedback and nonlinear state feedforward. That is, u = f (X, t) + g (X, t) · U (8) where U = [u1, u2] ^T , where u1 is a control command value for determining the blower voltage, and u2 Is a control command value for determining the blowing temperature. F (X, t) is a nonlinear feedback function, and g (X, t) is a nonlinear feedforward function. According to equation (8), U to Y are linearized and converted as in the following equation (FIG. 6 (b): dY / dt = A1 · Y + B1 · U (9) where A1, B1 Is a coefficient matrix.

The optimal regulator 74 has a reference model 71
Responsiveness using the evaluation function J to follow the target value of
Calculate the optimal value of the control constant to achieve both stability and control
To determine. The evaluation function J is represented by the following equation. J = ∫ ｛W1 · (ΔTinc)^Two+ W2 · (ΔTf)^Two+ W3 · (du1 / dt) 2 + W4 · (du2 / dt)^Two｝ Dt (10) where ΔTinc is the vehicle interior temperature Tinc and its target
Value Tinc^*ΔTf is the occupant skin temperature Tf
And its target value Tf^*Deviation, du1 / dt is the blower
Indicates a sharp difference in the change of the control command value that determines the drive voltage Vf.
Time differential value, du2 / dt, determines the blowing temperature To
Differential value indicating the sharp difference in the change of the control command value
1, W2, W3, and W4 are weight coefficients. ∫ is 0
The integral operation from to is shown. In the above equation, ΔTf is
Represents the local thermal sensation in the area where solar radiation or blowing wind hits, and d
u1 / dt and du2 / dt are blower noise and blowing
It expresses the sense of change in air flow and blowout temperature. These ΔTin
c, ΔTf, du1 / dt and du2 / dt are occupants.
Is a key parameter affecting the comfort of the
In order to evaluate comfort comfortably, the weight
The numbers W1, W2, W3, W4 are determined.

From the above equations (1), (2) and (9), an expansion system as shown in the following equation is constructed. dE / dt = Ae · E + Be · dU / dt (11) where E = [dY / dt, e, dXr / dt] ^T , Ae and Be are coefficient matrices, and e is a deviation vector (e = Yr-Y). In equation (11), the control law that minimizes the evaluation function J is represented by the following equation. dU / dt = K1 · dY / dt + K2 · e + K3 · dXr / dt (12) Here, K1, K2, and K3 are control constant matrices. The time differential value dU of the control command value vector of equation (12)
To keep / dt as small as possible and follow the target value, control constants K1, K2, and K3 are determined by the following equations. (K1, K2, K3) = − R ⁻¹ Be ^T P (13) Here, R is a weight coefficient matrix, and P is a matrix solution of the following Riccati equation. Ae ^T・ P + P ・ Ae + Q-P ・ Be ・ R ^-1・ Be ^T・ P = 0 (14) Here, Q is a weight coefficient matrix. in this way,
By setting the weight coefficient matrices Q and R, the control constants K1, K2 and K3 are determined according to a predetermined algorithm. The control constants K1, K2, determined by the above equation
By substituting K3 into equation (11) and integrating, the optimal control command value vector U, that is, the control amount of the air conditioning unit 2 is determined. U = K1 · Y + K2 · {edt + K3 · Xr + {U (0) −K1 · Y (0) −K3 · Xr (0)} (15) where U (0), Y (0), Xr (0) is a control command value, an output, and an initial value of a state variable, respectively.

FIG. 7 is a control block diagram showing the configuration of the optimal regulator 74 designed in this manner. FIG. 8 is a time chart showing a process of calculating the control command value of the optimal regulator 74. Optimal regulator 74
Difference, as shown at time t3 in FIG. 8, and the calculated target vehicle interior temperature Tinc ^* and the target skin temperature Tf ^* in the reference model 71, the estimated value Tf ^S of the actual cabin temperature Tinc and skin temperature The control amount of the air conditioning unit 2 is determined so that the area of the air conditioner is minimized. That is, while ensuring responsiveness and stability under all conditions based on the evaluation function J for evaluating the comfort of the occupant, the air conditioning unit 2 is controlled so that the temperature target value of the reference model 71 conforms to the comfort of the occupant. Control. Note that the control amount calculated by the optimal regulator 74 is linearized by the linear compensator 73 as described above.

FIG. 9 is a flowchart showing a control program executed by the microcomputer of the controller 7. The microcomputer starts executing the control program when a main switch (not shown) of the air conditioner is turned on. The operation of the controller 7 will be described with reference to this flowchart. In step S1, the vehicle interior temperature set value Tptc set by the room temperature setter 6 is set.
, And calculates the target skin temperature Tf ^* and the target vehicle interior temperature Tinc ^* that match the comfort of the occupant with the reference model 71, and outputs them to the optimal regulator 74. In the following step S2, the vehicle body temperature Tm, the blown air volume Ga, the air mix door opening Xmm, etc., which cannot be measured by the observer 72 or are difficult to measure, are estimated, and the current skin temperature Tf is predicted based on these estimated values. Output to the optimal regulator 74.

In step S3, the deviation from the target value is determined by the optimum regulator 74 based on the target value of the reference model 71, the estimated skin temperature Tf ^S estimated by the observer 72, and the measured vehicle interior temperature Tinc. The amount of change in the control amount is calculated, and the optimum control constant for following the target value is calculated by the evaluation function J. The control amount is determined and output to the linear compensator 73. Step S4
Then, the control amount from the optimal regulator 74 is linearized by the linear compensator 73. Then, in step S5, the linearized control amount is output to the air conditioning unit 2. The air conditioning unit 2 drives the actuators of the air mix door and each outlet door according to the control amount, and drives the blower to perform air conditioning of the passenger compartment 3.

As described above, in the reference model 71, the target skin temperature Tf ^{* in} the steady state and the transient state that matches the occupant's feeling of comfort ^.
The target vehicle interior temperature Tinc ^* is set, and the observer 72 estimates the unmeasurable or difficult-to-measure vehicle body temperature Tm, the blown air volume Ga, and the air mix door opening Xmm, and estimates these estimated values Tm ^S , Ga ^S , seeking skin temperature estimated value Tf ^S based on xmm ^S, optimal regulator 74
And the target skin temperature Tf ^* and the target vehicle interior temperature Tinc ^*
The optimum value of the control constant is calculated by the evaluation function J to follow the target value, the target skin temperature Tf ^* , the target vehicle interior temperature Tinc ^* , the estimated physical quantity Tm ^S of the observer 72, Ga
^S, since so as to determine the control amount based on the X mm ^S and measurable cabin temperature Tinc, it becomes possible to follow the target temperature while ensuring responsiveness and stability for all environmental conditions, Experimental man-hours for tuning control constants are reduced. Furthermore, observer 72
The skin temperature Tf, which is an important parameter for realizing comfortable air conditioning of the occupant, is estimated.
It is possible to detect the skin temperature Tf without wearing a skin temperature sensor that causes discomfort to the occupant.

In the above-described embodiment, the reference model 71 generates the target skin temperature Tf ^* and the target vehicle interior temperature Tinc ^* , and the observer 72 generates the vehicle body temperature Tm and the blowing air volume G.
a, Air mix door opening Xmm and skin temperature Tf
Is estimated, but the physical quantity generated by the reference model 71 and the physical quantity estimated by the observer 72 are not limited to the above embodiment.

In the configuration of the above embodiment, the air conditioning unit 2 controls the adjusting means, the observer 72 controls the skin temperature estimating means, the reference model 71 controls the target value generating means, the optimal regulator 74 controls the controlling means, and the air conditioning unit 2 controls the controlling means. The cabin 3 constitutes a control target.

[0023]

As described above, according to the present invention, a target value to be temporally changed between the vehicle interior temperature and the occupant's skin temperature is generated, and the occupant is identified by a mathematical model of the controlled object identified as the controlled object. The skin temperature of the air conditioning is estimated, and the temperature and air volume of the conditioned air are adjusted so that the detected vehicle interior temperature value and the estimated skin temperature value match the respective target values. Thereby, the present invention has the following effects. First, the values that should be changed over time to the target values of the vehicle interior temperature and skin temperature are set, so when changing the target values in accordance with changes in environmental conditions, the occupants can be used not only in the steady state but also in the transient state. It is possible to set an air-conditioning style that matches the comfort of the user. Further, since the target values of the vehicle interior temperature and the occupant's skin temperature are set, the man-hour for adjusting the device can be greatly reduced. That is, if the air conditioning control is performed only by the target value of the vehicle interior temperature, the number of combinations of the temperature of the conditioned air and the air volume can be made innumerable, and the combination must be narrowed down by experiments. In addition to the target temperature of the room temperature, the target value of the skin temperature of the occupant, which has a strong correlation with the occupant's thermal sensation, is set. . Next, since the occupant's skin temperature is estimated using the mathematical model identified as the control target, the skin temperature can be accurately estimated without using a contact-type sensor that causes discomfort to the occupant or a complicated and expensive non-contact type sensor. can do. Furthermore, since the temperature and air volume of the conditioned air are adjusted so that the vehicle interior temperature detection value and the skin temperature estimation value match the respective target values, air conditioning that matches the occupant's thermal sensation under all environmental conditions is performed. be able to.

[Brief description of the drawings]

FIG. 1 is a diagram corresponding to claims.

FIG. 2 is a block diagram showing a configuration of one embodiment.

FIG. 3 is a time chart showing a change in vehicle interior temperature when a set value of vehicle interior temperature is changed.

FIG. 4 is a control block diagram showing a configuration of an observer.

FIG. 5 is a diagram showing physical quantities relating to a heat load required for air conditioning control.

FIG. 6 is a control block diagram showing a linear compensator.

FIG. 7 is a control block diagram showing an optimal regulator.

FIG. 8 is a view for explaining a method of calculating a control amount in an optimal regulator.

FIG. 9 is a flowchart showing an example of a control program executed by a microcomputer of the controller.

FIG. 10 is a block diagram showing a conventional vehicle air conditioner.

[Explanation of symbols]

 2 Air-conditioning unit 4 Solar radiation sensor 5 Outside temperature sensor 6 Room temperature setting device 7 Controller 71 Reference model 72 Observer 73 Linear compensator 74 Optimal regulator

 ──────────────────────────────────────────────────続 き Continuing from the front page Judge of the colleague Judge Kenichi Awazu Judge Kohei Sakurai Judge Judge Hiroyuki Aida (56) Hei 2-109715 (JP, A) Real opening Hei 2-112573 (JP, U)

Claims (1)

(57) [Claims] 1. The temperature and air volume of conditioned air blown into a vehicle cabin
Adjusting means for adjusting, a cabin temperature detecting means for detecting a cabin temperature, and a control amount of the adjusting means as an input and a cabin temperature as an output.
Is a mathematical model of the control target previously identified as the control target.
The occupant's skin temperature as a state variable
And the output of the mathematical model and the temperature in the cabin.
Formula model that feeds back the deviation from the degree detection value
Having the skin temperature of the state variable of the mathematical model
Skin temperature estimating means for estimating skin temperature, and time course of vehicle interior temperature and occupant skin temperature
Target value generating means for generating a target value, the vehicle interior temperature detection value and the skin temperature estimation value
Match the vehicle interior temperature target value and the skin temperature target value
Calculating the control amount of the adjusting means for adjusting
Control means for controlling the air conditioner.