Air conditioner for automobiles

• US 4,696,167 A
• Filed: 10/18/1985
• Issued: 09/29/1987
• Est. Priority Date: 10/19/1984
• Status: Expired due to Term

• Current Assignee: Nippondenso Co., Ltd. (DENSO Corporation)
• Original Assignee: Nippondenso Co., Ltd. (DENSO Corporation)
• Inventors: Kawai, Takayoshi, Ohba, Masahiro, Matsui, Katsumasa, Kakehi, Tohru
• Primary Examiner(s): Tanner, Harry
• Application Number:
  US06/789,013
• Time in Patent Office: 711 Days
• Field of Search: 62/180, 62/243, 62/244, 62/239, 62/231, 62/157, 236/49, 236/78 D, 236/46 R, 236/46 C, 236/46 A, 165/42, 165/43, 165/44, 165/16, 165/12, 364/149, 364/150, 364/151, 364/557, 364/165
• US Class Current: 62/180
• CPC Class Codes: B60H 1/00735 Control systems or circuits characterised by their input, i.e. by the detection, measurement or calculation of particular conditions, e.g. signal treatment, dynamic models
• CPC Class Codes: G05B 13/045 using a perturbation signal
• CPC Class Codes: G05D 23/1917 using digital means
• CPC Class Codes: G05D 23/24 the sensing element having a resistance varying with temperature, e.g. a thermistor

Abstract

In an air conditioner for automobiles, control unit for performing feedback control of blow off air is constructed in the form of an integral-added optimal regulator (M4) which performs the feedback control on the basis of optimal feedback gain predetermined according to dynamic model(s) of an air conditioning system including the vehicle compartment (M1) and the used air conditioning unit (M2). According to another feature of the present invention, an environmental condition, such as solar radiation to the vehicle compartment (M1), is detected to further accurately control the internal air temperature. In one embodiment, the internal variables including optimal feedback gain of the integral-added optimal regulator (M4) are changed in accordance with the variation in the dynamic model depending on the detected environmental condition. In another embodiment, in addition to the above-mentioned feedback gain, feedforward gain is used so as to finally determine controlled variables of blow off air control unit (M2). Furthermore, according to another feature of the present invention, temperature control may be performed at a plurality of different positions within a vehicle compartment using a plurality of air conditioning units without suffering from interference between a plurality of airflows.

Claims

1. An air conditioner for a vehicle, comprising:

(a) air duct means for supplying a vehicle compartment with air;

(b) supply heat quantity controlling means for controlling an amount of heat of the air supplied from said air duct means to said vehicle compartment;

(c) temperature setting means for setting a target temperature for air in said vehicle compartment;

(d) compartment temperature detecting means for detecting an actual temperature of air in said vehicle compartment as a detected compartment temperature;

(e) deviation computing means for computing the temperature deviation of said detected compartment temperature from said target temperature;

(f) temperature perturbation component computing means for computing perturbation components of said detected compartment temperature relative to a reference temperature of said vehicle compartment under a steady air-conditioning state in a dynamic model used for controlling said heat quantity which is predetermined through system identification;

(g) internal state estimating means for estimating an estimated internal state of said dynamic model using said perturbation components computed by said temperature perturbation component computing means;

(h) adjusting amount perturbation component computing means for computing adjusting amount perturbation components of said supply heat quantity controlling means relative to a reference adjusting amount under said steady air-conditioning state in said dynamic model on the basis of said temperature deviation computed by said deviation computing means and said estimated internal state of said internal state estimating means; and

(i) control adjusting amount determining means for determining an adjusting amount of said amount of heat of air on the basis of said adjusting amount perturbation components and said reference adjusting amount.

2. An air conditioner as claimed in claim 1, wherein said supply heat quantity controlling means is also for to controlling:

(a) the amount of air fed from said air duct means to said vehicle compartment, (b) capability of cooling the air within said air duct means, and (c) the degree of reheating cooled air.

3. An air conditioner as claimed in claim 1, wherein said temperature perturbation component computing means comprises dynamic model selecting means for selecting a dynamic model that satisfies linear approximation in accordance with the deviation of detected compartment temperature, said dynamic model selecting means computing a reference compartment temperature under said steady air-conditioning state in a selected dynamic model.

4. An air conditioner as claimed in claim 1, wherein said internal state estimating means is also for computing a state estimation value indicative of an internal state of said dynamic model, on the basis of said adjusting amount perturbation components and said temperature perturbation components.

5. An air conditioner as claimed in claim 1, wherein said adjusting amount perturbation component computing means comprises integrator means for integrating said temperature deviation to provide an integrated temperature difference, and feedback amount computing means for computing said adjusting amount perturbation component on the basis of said integrated temperature difference from said integrator means, said estimated internal state obtained by said internal state estimating means, and an optimal feedback gain for causing said compartment temperature with said dynamic model to approach said target temperature.

6. An air conditioner as claimed in claim 3, wherein said adjusting amount perturbation component computing means comprises integrator means for integrating said temperature deviation to provide an integrated temperature difference, and feedback amount computing means for computing said adjusting amount perturbation component on the basis of said integrated temperature difference from said integrator means, said estimated internal state obtained by said internal state estimating means, and an optimal feedback gain for causing said compartment temperature with said dynamic model to approach said target temperature, said feedback amount computing means comprising feedback gain determining means for determining said optimal feedback gain in accordance with said dynamic model selected by said dynamic model selecting means.

7. An air conditioner for a vehicle, comprising:

(a) air duct means for supplying a vehicle compartment with air;

(b) supply heat quantity controlling means for controlling a quantity of heat of air supplied from said air duct means to said vehicle compartment;

(c) temperature setting means for setting a target temperature for air in said vehicle compartment;

(d) compartment temperature detecting means for detecting an actual detected temperature of air in said vehicle compartment;

(e) deviation computing means for computing a temperature deviation of said detected temperature in said compartment from said target temperature;

(f) air-conditioning environmental condition detecting means for detecting an environmental condition having an influence on the change of said compartment air temperature;

(g) temperature perturbation component computing means for computing perturbation components of said detected compartment temperature relative to a reference temperature of said vehicle compartment under a steady air-conditioning state in a dynamic model used for controlling said heat quantity which is predetermined through system identification;

(h) internal state estimating means for estimating the internal state of said dynamic model as an estimated internal state using the detected air-conditioning environmental condition said perturbation components computed by said temperature perturbation component computing means;

(i) adjusting amount perturbation component computing means for computing adjusting amount perturbation components of said supply heat quantity controlling means relative to a reference adjusting amount under said steady air-conditioning state in said dynamic model on the basis of said temperature deviation computed by said deviation computing means, said detected air-conditioning environmental condition, and said estimated internal state from said internal state estimating means; and

(j) control adjusting amount determining means for determining an adjusting amount of said supply heat quantity on the basis of said adjusting amount perturbation components and said reference adjusting amount.

8. An air conditioner as claimed in claim 7, wherein said supply heat quantity controlling means is also for controlling:

(a) the amount of air fed from said air duct means to said vehicle compartment, (b) a capability of cooling the air within said air duct means, and (c) the degree of reheating cooled air.

9. An air conditioner as claimed in claim 7, wherein said internal state estimating means is also for computing a state estimation value indicative of said internal state of said dynamic model on the basis of said air-conditioning environmental condition, said adjusting amount perturbation components, and said temperature perturbation components.

10. An air conditioner as claimed in claim 7, wherein said temperature perturbation component computing means comprises dynamic model selecting means for selecting a dynamic model which satisfies linear approximation in accordance with the change of detected compartment temperature, said dynamic model selecting means computing a reference compartment temperature under said steady air-conditioning state in a selected dynamic model.

11. An air conditioner as claimed in claim 7, wherein said adjusting amount perturbation component computing means comprises integrator means for integrating said temperature deviation to produce an integrated temperature difference, and feedback amount computing means for computing said adjusting amount perturbation component on the basis of said integrated temperature difference from said integrator means, said estimated internal state from said internal state estimating means, said air-conditioning environmental condition, and an optimal feedback gain for causing said compartment temperature with said dynamic model to approach said target temperature.

12. An air conditioner as claimed in claim 10, wherein said adjusting amount perturbation component computing means comprises integrator means for integrating said temperature deviation to produce an integrated temperature difference, and feedback amount computing means for computing said adjusting amount perturbation component on the basis of saod integrated temperature difference from said integrator means, said estimated internal state from said internal state estimating means, said air-conditioning environmental condition, and an optimal feedback gain for causing said compartment temperature with said dynamic model to approach said target temperature, said feedback amount computing means comprising feedback gain determining means for determining said optimal feedback gain in accordance with said dynamic model selected by said dynamic model selecting means, and said air-conditioning environmental condition.

13. An air conditioner as claimed in claim 7, wherein said adjusting amount perturbation component computing means comprises integrator means for integrating said temperature deviation to produce an integrated temperature difference;

feedback amount computing means for computing said adjusting amount perturbation component on the basis of said integrated temperature difference from said integrator means, said estimated internal state from internal state estimating means, and an optimal feedback gain, for causing said compartment temperature with said dynamic model to approach said target temperature; and

feedforward amount computing means for computing a feedforward gain according to said dynamic model and for computing a feedforward amount to be added to said adjusting amount perturbation component computed by said feedback amount computing means on the basis of said feedforward gain.

14. An air conditioner as claimed in claim 7, wherein said air-conditioning environmental condition detecting means is arranged to detect at least one of amount of solar radiation, exterior temperature, humidity, vehicle speed, and speed of the engine of said vehicle.

15. An air conditioner for a vehicle, comprising:

(a) air duct means for supplying a vehicle compartment with air through a plurality of air outlets to blow air toward a plurality of positions in said vehicle compartment;

(b) supply heat quantity controlling means for controlling the quantity of heat of air supplied from said air duct means to said vehicle compartment;

(c) temperature setting means for setting a target temperature for air in said vehicle compartment;

(d) compartment temperature detecting means for detecting actual detected temperatures of air at said plural positions in said vehicle compartment;

(e) deviation computing means for computing a temperature deviation of a detected compartment temperature from said target temperature for each of said temperatures at said plural positions;

(f) temperature perturbation component computing means for computing respective perturbation components of said detected compartment temperatures at said plural positions relative to a plurality of reference temperatures for said plural positions in said vehicle compartment under a steady air-conditioning state in a dynamic model used for controlling said heat quantity which is predetermined through system identification;

(g) internal state estimating means for estimating the internal state of said dynamic model as an estimated internal state using said perturbation components computed by said temperature perturbation component computing means;

(h) adjusting amount perturbation component computing means for computing adjusting amount perturbation components of said supply heat quantity controlling means relative to a reference adjusting amount under said steady air-conditioning state in said dynamic model on the basis of said temperature deviation computed by said deviation computing means and said estimated internal state; and

(i) control adjusting amount determining means for determining an adjusting amount of said supply heat quantity on the basis of said adjusting amount perturbation components and said reference adjusting amount.

16. An air conditioner as claimed in claim 15, wherein said supply heat quantity controlling means is also for controlling (a) an amount of air fed from said air duct means to said vehicle compartment, (b) a capability of cooling the air within said air duct means, and (c) the degree of reheating cooled air.

17. An air conditioner as claimed in claim 15, wherein said temperature perturbation component computing means comprises dynamic model selecting means for selecting a dynamic model satisfies linear approximation in accordance with the deviation of detected compartment temperature, said dynamic model selecting means computing a reference compartment temperature under said steady air-conditioning state in a selected dynamic model.

18. An air conditioner as claimed in claim 15, wherein said internal state estimating means is arranged to compute a state estimation value indicative of said internal state of said dynamic model on the basis of said adjusting amount perturbation components and said temperature perturbation components.

19. An air conditioner as claimed in claim 15, wherein said adjusting amount perturbation component computing means comprises integrator means for respectively integrating said temperature deviations to produce an integrated temperature difference, and feedback amount computing means for computing said adjusting amount perturbation component on the basis of said integrated temperature difference from said integrator means, said estimated internal state from said internal state estimating means, and an optimal feedback gain for causing said compartment temperature with said dynamic model to approach said target temperature.