Method for controlling vehicle air-conditioning system, and vehicle air-conditioning system

Patent metadata

Field	Value
Publication number	US-10486499-B2
Application number	US-201314904802-A
Country	US
Kind code	B2
Filing date	Jul 18, 2013
Priority date	Jul 18, 2013
Publication date	Nov 26, 2019
Grant date	Nov 26, 2019

Abstract

A method for controlling a vehicle air-conditioning system and a vehicle air-conditioning system, the method includes acquiring an actual degree of superheat, a preset degree of superheat and a degree of opening of an electronic expansion valve; determining, according to the actual degree of superheat, the preset degree of superheat and the degree of opening of the electronic expansion valve and whether the electronic expansion valve is in a fault state; and outputting a control signal to an executive control mechanism to adjust a parameter of a device in a vehicle air-conditioning system, which influences the variation of the actual degree of superheat, so as to adjust the degree of superheat of the vehicle air-conditioning system.

First claim

The invention claimed is:

1. A control method for a vehicle air-conditioning system, comprising successive diagnosis cycles, wherein each of the successive diagnosis cycles comprises:
acquiring, while performing a superheat degree control, an opening degree of an electronic expansion valve, an actual superheat degree, and a preset superheat degree;
adding one to a quantity of abnormality times of the electronic expansion valve in response to the vehicle air-conditioning system meeting a first condition or a second condition; and
resetting the quantity of abnormality times to be zero and entering a next one of the successive diagnosis cycles in response to the vehicle air-conditioning system meeting neither the first condition nor the second condition;
wherein after adding one to the quantity of abnormality times of the electronic expansion valve, the method further comprises:
determining that the electronic expansion valve is in a fault state in response to the quantity of abnormality times being greater than or equal to a preset number; and
entering the next one of the successive diagnosis cycles in response to the quantity of abnormality times being smaller than a preset number;

wherein after determining that the electronic expansion valve is in the fault state, the method further comprises:
outputting a control signal to a vehicle-mounted electronic control unit (ECU); and
adjusting, by the vehicle-mounted ECU, a device to adjust the superheat degree of the vehicle air-conditioning system, wherein the device comprises at least one of a compressor, an evaporator fan or a condenser fan; or controlling, by the vehicle-mounted ECU, to turn off the device or the air-conditioning system;

wherein the first condition is: a result of the preset superheat degree minus the actual superheat degree being greater than a first fixed value, and the opening degree of the electronic expansion valve reaching a minimum value, and
wherein the second condition is: a result of the actual superheat degree minus the preset superheat degree being greater than a second fixed value, and the opening degree of the electronic expansion valve reaching a maximum value.

2. The control method for the vehicle air-conditioning system according to claim 1 , wherein each of the successive diagnosis cycles comprises:
S 01 , acquiring the opening degree of the electronic expansion valve, the actual superheat degree, and the preset superheat degree, and going to step S 021 ;
S 021 , determining whether the preset superheat degree minus the actual superheat degree is greater than the first fixed value (w 1 ), and going to S 022 if the preset superheat degree minus the actual superheat degree is greater than the first fixed value (w 1 ), and going to step S 025 if the preset superheat degree minus the actual superheat degree is not greater than the first fixed value (w 1 );
S 022 , determining whether the opening degree of the electronic expansion valve reaches the minimum value; and going to step S 023 if the opening degree of the electronic expansion valve reaches the minimum value, and going to step S 025 if the opening degree of the electronic expansion valve does not reach the minimum value;
S 023 , adding 1 to the quantity of abnormality times (n), and going to step S 024 ;
S 024 , determining whether the quantity of abnormality times (n) is greater than or equal to the preset number (N); and if the quantity of abnormality times (n) is greater than or equal to the preset number (N), determining that the electronic expansion valve is currently in the fault state, and going to step S 03 or simultaneously going to step S 03 and step S 05 ;
S 025 , determining whether the actual degree of superheat minus the preset degree of superheat is greater than the second fixed value (w 2 ); and going to step S 026 if the actual degree of superheat minus the preset degree of superheat is greater than the second fixed value (w 2 ), and going to step S 05 if the actual degree of superheat minus the preset degree of superheat is not greater than the second fixed value (w 2 );
S 026 , determining whether the opening degree of the electronic expansion valve reaches the maximum value, and going to step S 023 if the opening degree of the electronic expansion valve reaches the maximum value; and going to step S 05 if the opening degree of the electronic expansion valve does not reach the maximum value;
S 03 , outputting the control signal of fault of the electronic expansion valve to the vehicle-mounted ECU; and
S 05 , resetting the quantity of abnormality times (n).

3. The control method for the vehicle air-conditioning system according to claim 2 , wherein before determining that the electronic expansion valve is in the fault state, the method comprises:
entering the next one of the successive diagnosis cycles in response to determining that an operating environment meets an operating limit of the air-conditioning system.

4. The control method for the vehicle air-conditioning system according to claim 2 , wherein performing the superheat degree control comprises:
acquiring, by a control system in real time, an actual superheat degree, a preset superheat degree, and a feedforward information affecting the change of the actual superheat degree, wherein the feedforward information comprising the change of the rotational speed and/or displacement of the compressor; and/or the change of the rotational speed of the evaporator fan; and
adjusting the opening degree of the electronic expansion valve in real time according to the actual superheat degree, the preset superheat degree, and the feedforward information acquired, to control the superheat degree of the vehicle air-conditioning system.

5. The control method for the vehicle air-conditioning system according to claim 1 , wherein each of the successive diagnosis cycles comprises:
S 01 , acquiring the opening degree of the electronic expansion valve, the actual superheat degree, and the preset superheat degree, and going to step S 025 ;
S 025 , determining whether the actual superheat degree minus the preset superheat degree is greater than the second fixed value (w 2 ); and going to step S 026 if the actual superheat degree minus the preset superheat degree is greater than the second fixed value (w 2 ), and going to step S 021 if the actual superheat degree minus the preset superheat degree is not greater than the second fixed value (w 2 );
S 026 , determining whether the opening degree of the electronic expansion valve reaches the maximum value; and going to step S 023 if the opening degree of the electronic expansion valve reaches the maximum value, and going to step S 021 if the opening degree of the electronic expansion valve does not reach the maximum value;
S 023 , adding 1 to the quantity of abnormality times (n), and going to step S 024 ;
S 021 , determining whether the preset superheat degree minus the actual superheat degree is greater than the first fixed value (w 1 ); and going to step S 022 if the preset superheat degree minus the actual superheat degree is greater than the first fixed value (w 1 ), and going to step S 05 if the preset superheat degree minus the actual superheat degree is not greater than the first fixed value (w 1 );
S 022 , determining whether the opening degree of the electronic expansion valve reaches the minimum value; and going to step S 023 if the opening degree of the electronic expansion valve reaches the minimum value, and going to step S 05 if the opening degree of the electronic expansion valve does not reach the minimum value;
S 024 , determining whether the quantity of abnormality times (n) is greater than or equal to the preset number (N); and determining that the electronic expansion valve is in the fault state currently, and going to

Assignees

• Hangzhou Sanhua Res Inst Co Ltd

Inventors

• Stanke Edwin J
• Zhang Rongrong
• Tang Li
• Zhang Jun

Classifications

• B60H2001/3285

  related to an expansion unit · CPC title

• B60H2001/3267

  related to the operation of an expansion valve · CPC title

• B60H1/3225

  characterised by safety arrangements, e.g. compressor anti-seizure means or by signalling devices · CPC title

• F25B2500/19

  Calculation of parameters · CPC title

• F25B2600/2513

  Expansion valves · CPC title