Passenger car air conditioner out-of-season verification system and method

Abstract

The invention belongs to the technical field of air conditioner verification, and provides a passenger car air conditioner out-of-season verification system and method.The resistance detector is provided with a first defrosting temperature detection line and a second defrosting temperature detection line which are used for detecting a defrosting sensor, and an in-car temperature detection line used for detecting an in-car temperature sensor; the pressure switch detection line is used for detecting the pressure sensor; after the detection resistance values of the defrosting sensor, the pressure sensor and the in-vehicle temperature sensor are judged to be normal, analog PWM signals of the PWM signal generator are transmitted to the to-be-detected air-conditioning system, and the to-be-detected air-conditioning system is verified and detected through the large-current detector, so that out-of-season verification of the air-conditioning system is realized; the bus air conditioning system can verify the functions of the air conditioning system in low-temperature environments in spring, autumn and winter, the verification process does not need tedious operation, and the verification efficiency and quality of the functions of the bus air conditioning system can be ensured when the bus air conditioning system leaves a factory.

Description

Technical Field

[0001] The invention belongs to the technical field of air conditioning verification, and in particular relates to a bus air conditioning off-season verification system and method. Background Art

[0002] During the process of bus production, delivery and sales, effective verification of the air-conditioning system function can ensure the factory qualification rate of the bus and reduce the maintenance rate of the bus after sales. Therefore, before the bus leaves the factory and is sold, the bus will be started and the air-conditioning system on the bus will be verified to ensure the normal operation of the air-conditioning system during the later use of the bus and reduce the failure rate of the bus air-conditioning system.

[0003] The operation of the bus air-conditioning system is affected by factors such as ambient temperature, pipeline pressure and pulse signal adjustment. When the temperature is too low or the pipeline is abnormal, the normal function of the air-conditioning system cannot be effectively verified. Therefore, when buses are manufactured and sold in spring, autumn and winter, the pressure sensors, temperature sensors, condensers, evaporators and compressors installed in the air-conditioning system cannot be effectively verified, which leads to frequent failures of the air-conditioning system on buses and huge market maintenance service costs. The verification method of pressure sensors, temperature sensors, condensers, evaporators and compressors through multimeters or power wiring can avoid the influence of temperature and pipeline pressure to a certain extent, but its operation is cumbersome, greatly affected by human factors, and inefficient. Summary of the invention

[0004] In order to solve the above problems, the present invention proposes a bus air-conditioning off-season verification system and method. After the host computer determines that the detection resistance values ​​of the defrost sensor, the pressure sensor and the in-car temperature sensor are normal, the analog PWM signal of the PWM signal generator is transmitted to the air-conditioning system to be tested through the communication relay module, and the air-conditioning system to be tested is verified and tested by a large current detector, thereby realizing the off-season verification of the air-conditioning system. The bus air-conditioning system can verify the function of the air-conditioning system in the environment of lower temperature in spring, autumn and winter, thereby ensuring the normal operation of various components in the bus air-conditioning system, improving the off-season verification quality of the air-conditioning system, avoiding the influence of temperature and pipeline pressure, and the verification process does not require cumbersome operations, which can ensure the verification efficiency and quality of the function of the bus air-conditioning system when leaving the factory.

[0005] In order to achieve the above-mentioned purpose, in a first aspect, the present invention provides a bus air conditioning off-season verification system, which adopts the following technical scheme:

[0006] A passenger car air conditioning off-season verification system comprises a host computer, and a resistance detector, a large current detector, a PWM signal generator and a communication relay module connected to the host computer;

[0007] The resistance detector is provided with a first defrost temperature detection line and a second defrost temperature detection line for detecting the defrost sensor, an in-vehicle temperature detection line for detecting the in-vehicle temperature sensor, and a pressure switch detection line for detecting the pressure sensor;

[0008] The host computer is used to determine that the detection resistance values ​​of the defrost sensor, the pressure sensor and the in-vehicle temperature sensor are normal, and then transmit the analog PWM signal of the PWM signal generator to the air-conditioning system to be tested through the communication relay module, and verify and detect the air-conditioning system to be tested through the large current detector.

[0009] Furthermore, the air-conditioning system to be tested is connected to a first power supply, and the resistance detector, the high current detector and the PWM signal generator are connected to a second power supply.

[0010] Furthermore, the resistance detector, the high current detector, the PWM signal generator and the communication relay module are connected to the air conditioning system socket.

[0011] Furthermore, the communication relay module includes a first relay, a second relay, a third relay and a fourth relay, which are respectively used to transmit the evaporator low speed signal, the condenser working signal, the compressor start signal and the fresh air mechanism opening signal to the air conditioning system to be tested.

[0012] Furthermore, the air conditioning system to be tested includes a compressor, a condenser, a fresh air mechanism and an evaporator.

[0013] In order to achieve the above-mentioned purpose, in a second aspect, the present invention also provides a bus air conditioner off-season verification method, which adopts the following technical scheme:

[0014] A bus air conditioning off-season verification method adopts the bus air conditioning off-season verification system as described in the first aspect, including: after determining that the detection resistance values ​​of the defrost sensor, the pressure sensor and the in-vehicle temperature sensor are normal, transmitting an analog PWM signal to the air conditioning system to be tested, and verifying and testing the air conditioning system to be tested through a large current detector.

[0015] Further, the second relay, the first relay, the third relay and the fourth relay are turned on in sequence, and after the signals corresponding to the previous relays pass through in sequence, the next step of the program is entered.

[0016] Further, the resistance values ​​of the pressure sensor, the defrost temperature sensor and the in-vehicle temperature sensor are measured in sequence; when the resistance value detected by the pressure sensor channel is less than or equal to the first preset resistance value, it indicates that the high-pressure switch and the low-pressure switch are normal; when the resistance value detected by the pressure sensor channel is greater than the second preset resistance value, it indicates that the pressure switch is not connected, the pressure switch is broken or damaged, or the pressure of the high and low pressure pipelines exceeds the requirement; when the resistance value detected by the pressure sensor channel is greater than the first preset resistance value and less than the second preset resistance value, it indicates that the wiring harness has a virtual connection or the pipeline pressure is at a critical point; the first preset resistance value is less than the second preset resistance value;

[0017] After the air conditioning pipeline pressure is normal, the defrost temperature sensor resistance detection is started. When the defrost sensor detection resistance is less than or equal to the third preset resistance, the defrost sensor is normal, and the air conditioning compressor is turned on normally without limiting the duration; when the defrost sensor detection resistance is greater than the third preset resistance and less than or equal to the fourth preset resistance, the defrost sensor is prone to frost, and the compressor start time is controlled within the preset time; when the defrost sensor detection resistance is greater than the fourth preset value, it means that the defrost sensor is not connected or is broken; the third preset resistance is less than the fourth preset resistance;

[0018] After the defrost temperature sensor is normal, the in-vehicle temperature sensor is detected. When the detected resistance value of the in-vehicle temperature sensor is less than the fifth preset resistance value, the air-conditioning compressor is turned on normally without limiting the duration; when the detected resistance value of the in-vehicle temperature sensor is greater than the fifth preset resistance value and not greater than the sixth predicted resistance value, the compressor start time is controlled within the preset time; when the detected resistance value of the in-vehicle temperature sensor is greater than the sixth predicted resistance value, it means that the defrost sensor is not connected or is damaged; the fifth preset resistance value is less than the sixth preset resistance value.

[0019] Furthermore, the wind speed change of the evaporator in the air-conditioning system is controlled by a PWM signal, the PWM duty cycle automatically increases from 0 to 100%, and then the PWM signal duty cycle automatically decreases from 100% to 0%, and a current curve is obtained using a large current detector; if there is an abnormal change in the current curve, the fan in the evaporator is abnormal or the logic is disturbed and the operation is abnormal.

[0020] Furthermore, the circuit operating current of the condenser, evaporator, compressor and fresh air mechanism in the air-conditioning system is detected by a large current detector. If the current deviation of the condenser and evaporator exceeds the first preset range value, it means that there is a problem with the fan coil, and the abnormal problem locations of the condenser and evaporator are obtained according to the opening sequence; if the current deviation of the fresh air mechanism and compressor exceeds the second preset range value, it means that there is an abnormality in the fresh air mechanism and the compressor.

[0021] Compared with the prior art, the present invention has the following beneficial effects:

[0022] 1. In the present invention, a first defrost temperature detection line and a second defrost temperature detection line for detecting a defrost sensor, an in-car temperature detection line for detecting an in-car temperature sensor, and a pressure switch detection line for detecting a pressure sensor are arranged on the resistance detector; during verification detection, after the host computer determines that the detection resistance values ​​of the defrost sensor, the pressure sensor and the in-car temperature sensor are normal, the analog PWM signal of the PWM signal generator is transmitted to the air-conditioning system to be tested through the communication relay module, and the air-conditioning system to be tested is verified and tested through a large current detector, thereby realizing off-season verification of the air-conditioning system. The bus air-conditioning system can verify the function of the air-conditioning system in an environment with lower temperatures in spring, autumn and winter, thereby ensuring the normal operation of various components in the bus air-conditioning system, improving the off-season verification quality of the air-conditioning system, avoiding the influence of temperature and pipeline pressure, and the verification process does not require cumbersome operations, which can ensure the verification efficiency and quality of the function of the bus air-conditioning system when it leaves the factory.

[0023] 2. In the present invention, the first power supply is used to power the air-conditioning system to be tested, and the second power supply is used to power the resistance detector, the large current detector and the PWM signal generator; the setting of the first power supply and the second power supply realizes the setting mode of the same voltage but different sources for the verification system and the air-conditioning system, and the power supplies of the verification system and the air-conditioning system are separated, thus avoiding the common ground interference problem.

[0024] 3. In the present invention, the second relay, the first relay, the third relay and the fourth relay are turned on in sequence, and the next step of the program is entered after the signals corresponding to the previous relays pass through in sequence, thereby avoiding the problem that when the compressor is turned on first, the condenser or evaporator does not work, resulting in high-temperature damage to the condenser, reducing the intensity of frequent manual operations and misoperations, and realizing simulated manual operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The drawings in the specification that constitute a part of this embodiment are used to provide a further understanding of this embodiment. The schematic embodiments of this embodiment and their descriptions are used to explain this embodiment and do not constitute improper limitations on this embodiment.

[0026] Figure 1 This is a schematic diagram of the system structure of Embodiment 1 of the present invention;

[0027] Figure 2 This is a diagram showing the verification working principle of Example 1 of the present invention;

[0028] Among them, 1. the first power supply; 2. the resistance detector; 3. the second power supply; 4. the PWM signal generator; 5. the host computer; 6. the air conditioning system to the socket strip; 7. the high current detector; 8. the communication relay module; 801. the first relay; 802. the second relay; 801. the third relay; 801. the fourth relay; 9. the data line; 10. the first defrost temperature detection line; 11. the second defrost temperature detection line; 12. the in-vehicle temperature detection line; 13. the pressure switch detection line; 14. the compressor; 15. the condenser; 16. the fresh air mechanism; 17. the evaporator; 18. the control panel socket strip; 19. the temperature sensor; 20. the pressure switch; 21. the first condenser control panel; 22. the second condenser control panel; 23. the evaporator excitation control panel. DETAILED DESCRIPTION

[0029] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0030] It should be noted that the following detailed descriptions are exemplary and are intended to provide further explanation of the present application. Unless otherwise specified, all technical and scientific terms used herein have the same meanings as those commonly understood by those skilled in the art to which the present application belongs.

[0031] Embodiment 1:

[0032] like Figure 1 As shown, this embodiment provides a bus air conditioning off-season verification system, including a first power supply 1, a resistance detector 2, a second power supply 3, a PWM signal generator 4, a host computer 5, an air conditioning system socket 6, a large current detector 7, a communication relay module 8, and a data line 9. The communication relay module 8 includes a first relay 801, a second relay 802, a third relay 803, and a fourth relay 804.

[0033] Specifically, the resistance detector 2, the PWM signal generator 4, the large current detector 7, the communication relay module 8, etc. are connected to the host computer 5 through the data line 9. The resistance detector 2, the PWM signal generator 4, the large current detector 7, the communication relay module 8, etc. are connected to the air conditioning system socket 6. Through the host computer 5, the communication relay module 8 and the PWM signal generator 4, the evaporator 17, the condenser 15, the compressor 14 and the fresh air mechanism 16 can be simulated and controlled; the current is detected by the large current detector 7, so as to realize the rapid detection of the bus air conditioning system, eliminate the influence of off-season pressure and temperature on the air conditioning system, and can quickly realize the automatic detection and verification of the bus air conditioning system, thereby improving the online debugging efficiency and control quality of the air conditioning system.

[0034] Optionally, the first power supply 1 can adopt a 5000W 24V high-power power supply; the second power supply 3 can adopt a 200W 24V device power supply; the communication relay module 8 is a 485 communication relay module; the evaporator 17 can adopt a seven-speed evaporation fan; the condenser 15 can adopt a condensing fan; the data cable 9 can adopt a USB to 485 data cable.

[0035] like Figure 2 As shown, the air-conditioning system in this embodiment may include a compressor 14, a condenser 15, a fresh air mechanism 16, an evaporator 17, a control panel strip 18, a temperature sensor 19, a pressure switch 20, a first condenser control panel 21, a second condenser control panel 22 and an evaporator excitation control panel 23, etc.

[0036] like Figure 2 As shown, the first power supply 1 is used to power the compressor 14, the condenser 15, the fresh air mechanism 16, and the evaporator 17, etc.; the second power supply 3 is used to power the resistance detector 2, the large current detector 7, and the PWM signal generator 4, etc. The setting of the first power supply 1 and the second power supply 3 realizes the setting mode of the verification system and the air conditioning system with the same pressure but different sources, and the power supply of the verification system and the air conditioning system is separated, avoiding the common ground interference problem.

[0037] like Figure 1 and Figure 2 As shown, the host computer 5 automatically controls the communication relay module 8 to sequentially open the first relay 801, the second relay 802, the third relay 803 and the fourth relay 804, and obtains the evaporator low speed signal, the condenser working signal, the compressor start signal and the fresh air mechanism opening signal. It has a sequential operation sequence, and only after passing through the sequence can the next step of the program be entered, so as to avoid the problem that when the compressor 14 is turned on first, the condenser 15 or the evaporator 17 does not work, resulting in the high temperature damage of the condenser 15, reduce the frequent manual operation intensity and misoperation, and realize simulated manual operation.

[0038] like Figure 1 and Figure 2 As shown, between the resistance detector and the air conditioning system, a first defrost temperature detection line 10, a second defrost temperature detection line 11, an in-vehicle temperature detection line 12 and a pressure switch detection line 13 are connected through the air conditioning system docking socket 6.

[0039] When the resistance detected by the pressure sensor channel is less than or equal to the first preset resistance, it means that the high-pressure switch and the low-pressure switch are normal; when the resistance detected by the pressure sensor channel is greater than the second preset resistance, it means that the pressure switch is not connected, the pressure switch is broken or the pressure of the high and low pressure pipelines exceeds the requirement; when the resistance detected by the pressure sensor channel is greater than the first preset resistance and less than the second preset resistance, it means that there is a virtual connection in the wiring harness or the pipeline pressure is at a critical point; the first preset resistance is less than the second preset resistance; after the air-conditioning pipeline pressure is normal, it enters the defrost temperature sensor resistance detection. When the defrost sensor detection resistance is less than or equal to the third preset resistance, the defrost sensor is normal and the air-conditioning compressor is turned on normally without limiting the duration; when the defrost sensor detection resistance is greater than the first preset resistance, the air-conditioning compressor is turned on normally without limiting the duration. When the resistance value detected by the defrost sensor is greater than the fourth preset resistance value and is less than or equal to the fourth preset resistance value, the defrost sensor is prone to frost, and at this time the compressor start-up time is controlled within the preset time; when the defrost sensor detection resistance value is greater than the fourth preset resistance value, it means that the defrost sensor is not connected or is damaged by a short circuit; the third preset resistance value is less than the fourth preset resistance value; after the defrost temperature sensor is normal, the in-vehicle temperature sensor is detected. When the in-vehicle temperature sensor detection resistance value is less than the fifth preset resistance value, the air-conditioning compressor is turned on normally without limiting the duration; when the in-vehicle temperature sensor detection resistance value is greater than the fifth preset resistance value and not greater than the sixth predicted resistance value, the compressor start-up time is controlled within the preset time; when the in-vehicle temperature sensor detection resistance value is greater than the seventh predicted resistance value, it means that the defrost sensor is not connected or is damaged by a short circuit.

[0040] Specifically, the resistance tester 2 is used to automatically measure the resistance values ​​of the pressure switch, the defrost temperature switch and the in-vehicle temperature switch in sequence; specifically, when the resistance detected by the pressure sensor channel is ≤30Ω, it means that the high-pressure switch and the low-pressure switch are normal; when the detected resistance is greater than 5KΩ, it means that the pressure switch is not connected, the pressure switch is short-circuited and damaged, or the pressure of the high and low pressure pipelines exceeds the requirement; when 30Ω<the detected resistance is ≤5KΩ, it means that there is a virtual connection in the wiring harness or the pipeline pressure is at a critical point.

[0041] After the air conditioning pipeline pressure returns to normal, the defrost temperature sensor resistance detection is started. When the defrost sensor detection resistance is <12KΩ (12K corresponds to 2℃, that is, the defrost temperature is ≥2℃), the defrost sensor is normal and the air conditioning compressor can be turned on normally without limiting the duration. The compressor is turned on for 15 minutes to test the sealing. When 5KΩ≤defrost temperature sensor detection resistance≤12KΩ (temperature is -30-2℃), the defrost sensor is prone to frost. At this time, the compressor start time is controlled within 2 minutes to protect the evaporator. When the defrost temperature is normal, the compressor is engaged and the working status test verification is completed; when the defrost temperature sensor temperature is >50KΩ, it means that the defrost sensor is not connected or is damaged.

[0042] After the defrost temperature sensor is normal, test the in-vehicle temperature sensor. When the resistance of the temperature sensor is ≤7KΩ (temperature ≥16℃), the air-conditioning compressor can be turned on normally without time limit. The compressor is turned on for 15 minutes to test the compressor sealing; when 7KΩ<temperature sensor detection resistance ≤11.72KΩ (temperature between -30-16℃), the compressor start-up time is controlled within 1 minute to avoid compressor liquid shock damage; when the temperature sensor temperature is greater than 50KΩ, it means that the defrost sensor is not connected or is damaged; the resistance value of each sensor and switch channel corresponds to the control logic and working status, which not only eliminates the influence and restriction of external temperature and environmental pressure on the air conditioner, but also realizes the off-season verification of the air-conditioning system.

[0043] like Figure 1 and Figure 2 As shown in the figure, the evaporator wind speed in the air conditioning system is controlled by the PWM signal. The PWM duty cycle is automatically increased from 0 to 100%, and then the PWM signal duty cycle is automatically decreased from 100% to 0%. The current curve is obtained by using a large current detector. If there is an abnormal change in the current curve, the fan in the evaporator is abnormal or the logic is disturbed and the operation is abnormal.

[0044] Specifically, after the resistance value is qualified, the program automatically controls the wind speed change of the evaporator 17 through the PWM signal emitted by the PWM signal generator 4. The PWM duty cycle is first automatically increased from 0 to 100%, so that the wind speed of the evaporator 17 is increased from the lowest gear to the highest gear. At this time, the current curve read by the large current detector 7 is an increasing current curve of 7-50A, and then the PWM signal duty cycle is automatically decreased from 100% to 0%, and the fan wind speed is reduced from full load to minimum load. At this time, the current curve read by the large current detector 7 is a decreasing current curve of 50-7A. If there is an abnormal change in the detected current curve, it means that the fan of the evaporator 17 is abnormal or the logic is disturbed and working abnormally. The PWM is automatically controlled by the program to increase and decrease the speed of the evaporator 17 in turn, which has a higher degree of automation and eliminates the incomplete signal verification caused by human laziness. At the same time, it cooperates with the large current sensor for detection to realize automatic judgment of the quality of the fan and control logic.

[0045] The circuit operating current of the condenser, evaporator, compressor and fresh air mechanism in the air-conditioning system is detected by a large current detector. If the current deviation of the condenser and evaporator exceeds the first preset range value, it means that there is a problem with the fan coil, and the abnormal location of the condenser and evaporator can be obtained according to the opening sequence; if the current deviation of the fresh air mechanism and compressor exceeds the second preset range value, it means that there is an abnormality in the fresh air mechanism and the compressor. Specifically, the working current of the main circuit of the condenser 15, the evaporator 17, the compressor 14 and the fresh air mechanism 16 is detected by the large current detector 7. The current of a single fan is 7A. The 1-7 gears correspond to the rotation of 1-7 fans. The current change should correspond to 7A, 14A, 21A, 28A, 35A, 42A and 49A. The control deviation range is ±1A. If it exceeds the range value, it means that there is a problem with the fan coil. The abnormal problem fan position of the condenser 15 and the evaporator 17 is quickly determined according to the opening sequence. The current of the fresh air mechanism 16 and the compressor 14 is 3A. The control deviation is about ±0.5A. If the current is checked to be beyond the control range, it means that there is an abnormality in the fresh air mechanism 16 and the compressor 14. Combined with the current change, it is quickly stacked to determine whether the working current of each system is normal, and the current value is transmitted to the host computer 5. At the same time, the host computer 5 quickly determines whether the working state of the condenser 15, the evaporator 17, the compressor 14 and the fresh air mechanism 16 is normal according to the preset value.

[0046] Embodiment 2:

[0047] This embodiment provides a bus air conditioning off-season verification system, and further illustrates the system in Embodiment 1.

[0048] Optional, such as Figure 2 As shown, the air conditioning system power cord and controller socket are connected to the air conditioning system socket 6. At this time, the "+" pole of the first power supply 1 is connected to the 150A power supply of the air conditioning system through the large current detector 2 to power the air conditioning system, and the other "+" pole is connected to the normally open pins of the evaporator low speed signal, the condenser working signal, the compressor start signal and the air conditioning fresh air start signal through the communication relay module 8. The second power supply supplies power to the first power supply 1, the resistance detector 1, the large current detector 7 and the PWM signal generator 4 respectively.

[0049] When the detection starts, the host computer 5 sends a signal instruction to the resistance detector 2 through the data line 9. The resistance detector 2 starts to detect the resistance values ​​of the pressure switch, the temperature sensor, and the defrost temperature sensor through the pressure switch detection line 13, the in-vehicle temperature detection line 12, the first defrost temperature detection line 10, and the second defrost temperature detection line 11. If the resistance value is consistent with the sensor range preset in the host computer 5, it is determined that the pressure switch and the sensor resistance value meet the test requirements, and the resistance value passes the test requirements, thereby entering the next test procedure; at this time, the host computer 5 sends instructions to the four relay closing instructions in the communication relay module 8 in turn through the data line 9, respectively controlling the evaporator low speed signal, the condenser signal, the compressor start signal and the air conditioner new The wind mechanism starts the signal. At this time, according to the corresponding instructions, the evaporator 17, condenser 15, compressor 14 and fresh air mechanism 16 in the air-conditioning system work in sequence; at the same time, the host computer 5 sends an instruction, and the PWM signal generator 4 controls the evaporator 15 to work through the duty cycle. At this time, the duty cycle is automatically adjusted from 0% to 100%, and then automatically adjusted from 100% to 0%. At this time, the large current detector 7 detects the current of each working state respectively, and transmits the current value to the host computer 5. The host computer 5 compares it with the preset current parameter value. If the deviation range is within the set range, it is judged to be qualified. If it fails, the failure is reported in the corresponding working link, so as to quickly determine whether the working states of the air-conditioning system are normal.

[0050] Embodiment 3:

[0051] The present embodiment provides a method for off-season verification of bus air conditioners, which adopts the off-season verification system of bus air conditioners as described in Example 1 or Example 2, including: after determining that the detection resistance values ​​of the defrost sensor, the pressure sensor and the in-vehicle temperature sensor are normal, transmitting the analog PWM signal to the air-conditioning system to be tested, and verifying and testing the air-conditioning system to be tested through a large current detector.

[0052] Optionally, the second relay, the first relay, the third relay and the fourth relay are turned on in sequence, and the next step of the program is entered after the signals corresponding to the previous relays pass through in sequence.

[0053] Optionally, measure the resistance values ​​of the pressure sensor, the defrost temperature sensor and the in-vehicle temperature sensor in turn; when the resistance detected by the pressure sensor channel is less than or equal to the first preset resistance, it means that the high-pressure switch and the low-pressure switch are normal; when the resistance detected by the pressure sensor channel is greater than the second preset resistance, it means that the pressure switch is not connected, the pressure switch is broken or the pressure of the high and low pressure pipelines exceeds the requirement; when the resistance detected by the pressure sensor channel is greater than the first preset resistance and less than the second preset resistance, it means that there is a virtual connection in the wiring harness or the pipeline pressure is at a critical point; the first preset resistance is less than the second preset resistance; after the air-conditioning pipeline pressure is normal, it enters the defrost temperature sensor resistance detection, and when the defrost sensor detection resistance is less than or equal to the third preset resistance, the defrost sensor is normal, and the air-conditioning compressor is turned on normally without limiting the duration; when the defrost sensor When the detected resistance is greater than the third preset resistance and less than or equal to the fourth preset resistance, the defrost sensor is prone to frost, and at this time the compressor start time is controlled within the preset time; when the detected resistance of the defrost sensor is greater than the fourth preset resistance, it means that the defrost sensor is not connected or is damaged by a short circuit; the third preset resistance is less than the fourth preset resistance; after the defrost temperature sensor is normal, the in-vehicle temperature sensor is detected. When the detected resistance of the in-vehicle temperature sensor is less than the fifth preset resistance, the air-conditioning compressor is turned on normally without limiting the duration; when the detected resistance of the in-vehicle temperature sensor is greater than the fifth preset resistance and not greater than the sixth predicted resistance, the compressor start time is controlled within the preset time; when the detected resistance of the in-vehicle temperature sensor is greater than the sixth predicted resistance, it means that the defrost sensor is not connected or is damaged by a short circuit; the fifth preset resistance is less than the sixth preset resistance.

[0054] Optionally, the wind speed change of the evaporator in the air-conditioning system is controlled by a PWM signal, the PWM duty cycle automatically increases from 0 to 100%, and then the PWM signal duty cycle automatically decreases from 100% to 0%, and a current curve is obtained using a large current detector; if there is an abnormal change in the current curve, the fan in the evaporator is abnormal or the logic is disturbed and the operation is abnormal.

[0055] Optionally, the circuit operating current of the condenser, evaporator, compressor and fresh air mechanism in the air-conditioning system is detected by a large current detector. If the current deviation of the condenser and evaporator exceeds the first preset range value, it means that there is a problem with the fan coil, and the abnormal location of the condenser and evaporator is obtained according to the opening sequence; if the current deviation of the fresh air mechanism and compressor exceeds the second preset range value, it means that there is an abnormality in the fresh air mechanism and the compressor.

[0056] The above description is only a preferred embodiment of the present embodiment and is not intended to limit the present embodiment. For those skilled in the art, the present embodiment may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present embodiment shall be included in the protection scope of the present embodiment.

Claims

1. A passenger car air conditioning off-season verification system, characterized in that: It includes a host computer, and a resistance detector, a large current detector, a PWM signal generator and a communication relay module connected to the host computer; The resistance detector is provided with a first defrost temperature detection line and a second defrost temperature detection line for detecting the defrost sensor, an in-vehicle temperature detection line for detecting the in-vehicle temperature sensor, and a pressure switch detection line for detecting the pressure sensor; The host computer is used to determine that the detection resistance values ​​of the defrost sensor, the pressure sensor and the in-vehicle temperature sensor are normal, and then transmit the analog PWM signal of the PWM signal generator to the air-conditioning system to be tested through the communication relay module, and verify and detect the air-conditioning system to be tested through the large current detector.

2. A passenger car air conditioning off-season verification system as claimed in claim 1, characterized in that: The air conditioning system to be tested is connected to a first power supply, and the resistance detector, the high current detector and the PWM signal generator are connected to a second power supply.

3. The off-season verification system for passenger car air conditioner according to claim 1, characterized in that: The resistance detector, the high current detector, the PWM signal generator and the communication relay module are connected to the air conditioning system socket.

4. The off-season verification system for passenger car air conditioner according to claim 1, characterized in that: The communication relay module includes a first relay, a second relay, a third relay and a fourth relay, which are respectively used to transmit the evaporator low speed signal, the condenser working signal, the compressor start signal and the fresh air mechanism opening signal to the air conditioning system to be tested.

5. The off-season verification system for passenger car air conditioner according to claim 1, characterized in that: The air conditioning system to be tested includes a compressor, a condenser, a fresh air mechanism and an evaporator.

6. A passenger car air conditioning off-season verification method, characterized in that: The off-season verification system for passenger car air conditioners as described in any one of claims 1 to 5 is adopted, comprising: after determining that the detection resistance values ​​of the defrost sensor, the pressure sensor and the in-car temperature sensor are normal, transmitting the analog PWM signal to the air-conditioning system to be tested, and verifying and testing the air-conditioning system to be tested through a large current detector.

7. A passenger car air conditioning off-season verification method as claimed in claim 6, characterized in that: Open the second relay, the first relay, the third relay and the fourth relay in sequence. After the signals corresponding to the previous relays pass through in sequence, enter the next step of the program.

8. A passenger car air conditioning off-season verification method as claimed in claim 6, characterized in that: Measure the resistance values ​​of the pressure sensor, defrost temperature sensor and in-vehicle temperature sensor in sequence; when the resistance value detected by the pressure sensor channel is less than or equal to the first preset resistance value, it indicates that the high-pressure switch and the low-pressure switch are normal; when the resistance value detected by the pressure sensor channel is greater than the second preset resistance value, it indicates that the pressure switch is not connected, the pressure switch is broken or damaged, or the pressure of the high and low pressure pipelines exceeds the requirement; when the resistance value detected by the pressure sensor channel is greater than the first preset resistance value and less than the second preset resistance value, it indicates that the wiring harness has a virtual connection or the pipeline pressure is at a critical point; the first preset resistance value is less than the second preset resistance value; After the air conditioning pipeline pressure is normal, the defrost temperature sensor resistance detection is started. When the defrost sensor detection resistance is less than or equal to the third preset resistance, the defrost sensor is normal, and the air conditioning compressor is turned on normally without limiting the duration; when the defrost sensor detection resistance is greater than the third preset resistance and less than or equal to the fourth preset resistance, the defrost sensor is prone to frost, and the compressor start time is controlled within the preset time; when the defrost sensor detection resistance is greater than the fourth preset value, it means that the defrost sensor is not connected or is broken; the third preset resistance is less than the fourth preset resistance; After the defrost temperature sensor is normal, the in-vehicle temperature sensor is detected. When the resistance value detected by the in-vehicle temperature sensor is less than the fifth preset resistance value, the air-conditioning compressor is turned on normally without limiting the duration; When the resistance detected by the in-vehicle temperature sensor is greater than the fifth preset resistance and not greater than the sixth predicted resistance, the compressor start time is controlled within the preset time; when the resistance detected by the in-vehicle temperature sensor is greater than the sixth predicted resistance, it means that the defrost sensor is not connected or is damaged; the fifth preset resistance is less than the sixth preset resistance.

9. A passenger car air conditioning off-season verification method as claimed in claim 6, characterized in that: The evaporator wind speed in the air conditioning system is controlled by a PWM signal. The PWM duty cycle automatically increases from 0 to 100%, and then the PWM signal duty cycle automatically decreases from 100% to 0%. A large current detector is used to obtain a current curve. If there is an abnormal change in the current curve, the fan in the evaporator is abnormal or the logic is disturbed and the operation is abnormal.

10. A passenger car air conditioning off-season verification method as claimed in claim 6, characterized in that: The circuit operating current of the condenser, evaporator, compressor and fresh air mechanism in the air-conditioning system is detected by a large current detector. If the current deviation of the condenser and evaporator exceeds the first preset range value, it means that there is a problem with the fan coil, and the abnormal location of the condenser and evaporator can be obtained according to the opening sequence; if the current deviation of the fresh air mechanism and compressor exceeds the second preset range value, it means that there is an abnormality in the fresh air mechanism and the compressor.

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