PTC auxiliary heating device control method and device, automobile air conditioner, medium and product

Abstract

The invention discloses a control method and device of a PTC auxiliary heating device, an automobile air conditioner, a storage medium and a computer program product.The method comprises the steps that under the condition that the PTC auxiliary heating device does not start to work after the automobile air conditioner is powered on, whether a direct current contactor breaks down or not is determined according to standby parameters of the automobile air conditioner; if yes, it is determined that the automobile air conditioner can be started and run according to the preset starting mode; if it is determined that the fault occurs, initiating a reminding message of the fault of the direct current contactor; according to the on-off parameters of the PTC protection loop, whether the temperature protection module breaks down or not is determined, and if not, it is determined that the automobile air conditioner can operate in a preset electric auxiliary heating mode; and if it is determined that a fault occurs, a reminding message that the temperature protection module has the fault is initiated. According to the scheme, protection measures are taken when faults of the direct current contactor and the temperature protection module are recognized, and the reliability and safety of the automobile air conditioner are improved.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of automobile air conditioners, and particularly relates to a control method and device of a PTC auxiliary heating device, an automobile air conditioner, a storage medium and a computer program product, in particular to a control method and device of a PTC auxiliary heating device of an electric automobile air conditioner, an automobile air conditioner, a storage medium and a computer program product. BACKGROUND

[0002] An automobile air conditioning system is a device for realizing functions of refrigeration, heating and ventilation of air in a vehicle cabin. In related solutions, a PTC (Positive Temperature Coefficient) air conditioner is generally used for heating in winter. With the rapid development of new energy and direct current products, the energy for operating an electric automobile air conditioner is derived from a vehicle power battery, and the market demand and market share are rapidly increasing.

[0003] In order to increase the endurance capability, the rated power supply voltage of the vehicle power battery is higher and higher. Limited by the selection of the rated voltage, the temperature limiter and thermal fuse protector of the PTC auxiliary heating device of the electric automobile air conditioner cannot be arranged in the PTC power main circuit, and only a low-voltage weak current on-off signal feedback circuit can be designed separately. The PTC auxiliary heating device is powered by controlling a direct current contactor. However, if the direct current contactor is stuck or the temperature limiter or thermal fuse protector is faultily disconnected and not restored, the safety of the air conditioner and the automobile is affected.

[0004] The above content is only used to assist in understanding the technical solutions of the present application and does not represent the acknowledgement of the above content as prior art. SUMMARY

[0005] The present application aims to provide a control method and device of a PTC auxiliary heating device, an automobile air conditioner, a storage medium and a computer program product, to solve the problem that the temperature limiter and thermal fuse protector of the PTC auxiliary heating device of the automobile air conditioner are located in a low-voltage weak current on-off signal feedback circuit, the PTC auxiliary heating device is powered by controlling a direct current contactor, and if the direct current contactor is stuck or the temperature limiter or thermal fuse protector is faultily disconnected and not restored, the safety of the air conditioner and the automobile is affected. The effect of improving the reliability and safety of the automobile air conditioner and the safety of the automobile is achieved by identifying the sticking fault of the direct current contactor and identifying the disconnection fault of the temperature limiter or thermal fuse protector, and then taking protective measures.

[0006] The application provides a control method of a PTC auxiliary heating device, which can be applied to an automobile air conditioner; the PTC auxiliary heating device comprises a PTC heating body and a temperature protection module; the PTC heating body is located in a PTC power supply circuit of the automobile air conditioner, and a direct current contactor is arranged at a power supply end of the PTC heating body; the temperature protection module is located in a PTC protection circuit of the automobile air conditioner; the control method of the PTC auxiliary heating device comprises the following steps: in the case that the PTC auxiliary heating device does not start working after the automobile air conditioner is powered on, standby parameters of the automobile air conditioner are acquired, and on-off parameters of the PTC protection circuit are acquired; whether the direct current contactor is faulty is determined according to the standby parameters of the automobile air conditioner; whether the temperature protection module is faulty is determined according to the on-off parameters of the PTC protection circuit; if it is determined that the direct current contactor is not faulty, it is determined that the automobile air conditioner can start and run in a preset start mode; if it is determined that the direct current contactor is faulty, a prompt message that the direct current contactor is faulty is initiated; if it is determined that the temperature protection module is not faulty, it is determined that the automobile air conditioner can run in a preset electric auxiliary heating mode; if it is determined that the temperature protection module is faulty, a prompt message that the temperature protection module is faulty is initiated.

[0007] In some embodiments, the automobile air conditioner has a main control board, a coil of the direct current contactor is connected with a first port of the main control board, contacts of the direct current contactor are connected between a power supply battery of the automobile air conditioner and the PTC heating body, and the standby parameters of the automobile air conditioner comprise an end voltage between the contacts of the direct current contactor; whether the direct current contactor is faulty is determined according to the standby parameters of the automobile air conditioner, which comprises the following steps: whether the end voltage between the contacts of the direct current contactor is the voltage of the power supply battery is determined, and whether the end voltage between the contacts of the direct current contactor is 0 is determined; if it is determined that the end voltage between the contacts of the direct current contactor is the voltage of the power supply battery, it is determined that the direct current contactor is not faulty; if it is determined that the end voltage between the contacts of the direct current contactor is 0, it is determined that the contacts of the direct current contactor are stuck, that is, it is determined that the direct current contactor is faulty.

[0008] In some embodiments, the automobile air conditioner has a main control board, a coil of the DC contactor is connected to a first port of the main control board, and a contact of the DC contactor is connected in the PTC power supply circuit; the standby parameters of the automobile air conditioner further include a current value of the PTC power supply circuit; and determining whether the DC contactor is faulty according to the standby parameters of the automobile air conditioner further includes determining whether the current value of the PTC power supply circuit is 0; if it is determined that the current value of the PTC power supply circuit is 0, it is determined that the DC contactor is not faulty; and if it is determined that the current value of the PTC power supply circuit is not 0, it is determined that the contact of the DC contactor is stuck, i.e., it is determined that the DC contactor is faulty.

[0009] In some embodiments, the automobile air conditioner has a main control board, a coil of the DC contactor is connected to a first port of the main control board, and a contact of the DC contactor is connected in the PTC power supply circuit; the standby parameters of the automobile air conditioner further include a current value of the PTC power supply circuit; and determining whether the DC contactor is faulty according to the standby parameters of the automobile air conditioner further includes determining whether the current value of the PTC power supply circuit is 0; if it is determined that the current value of the PTC power supply circuit is 0, it is determined that the DC contactor is not faulty; and if it is determined that the current value of the PTC power supply circuit is not 0, it is determined that the contact of the DC contactor is stuck, i.e., it is determined that the DC contactor is faulty.

[0010] In some embodiments, determining whether the temperature protection module is faulty according to the on-off parameters of the PTC protection circuit includes determining whether the PTC protection circuit is in a conducting state or a disconnected state according to the on-off parameters of the PTC protection circuit; if it is determined that the PTC protection circuit is in the conducting state, it is determined that the temperature protection module is not faulty; and if it is determined that the PTC protection circuit is in the disconnected state, it is determined that the temperature protection module is disconnected, i.e., it is determined that the temperature protection module is faulty.

[0011] In some embodiments, the determining whether the temperature protection module is faulty according to the on-off parameter of the PTC protection circuit further comprises: in the case that the temperature protection module is determined to be not faulty, controlling the PTC auxiliary heating device to operate in the electric auxiliary heating mode of the automobile air conditioner, and then determining whether the PTC protection circuit is in the on state or the off state according to the on-off parameter of the PTC protection circuit again; if the PTC protection circuit is determined to be in the on state, controlling the PTC auxiliary heating device to maintain the current operation; if the PTC protection circuit is determined to be in the off state, controlling the PTC auxiliary heating device to stop working, and controlling the fan of the automobile air conditioner to start and operate; after a set time, determining whether the PTC protection circuit is in the on state or the off state according to the on-off parameter of the PTC protection circuit; if the PTC protection circuit is determined to be in the on state, determining that the temperature protection module is not faulty; and if the PTC protection circuit is determined to be in the off state, determining that the temperature protection module is off and cannot be recovered, i.e., determining that the temperature protection module is faulty.

[0012] In another aspect, the present application provides a control device of a PTC auxiliary heating device, which can be applied to an automobile air conditioner. The PTC auxiliary heating device comprises a PTC heating body and a temperature protection module. The PTC heating body is located in a PTC power supply circuit of the automobile air conditioner, and a direct current contactor is arranged at a power supply end of the PTC heating body. The temperature protection module is located in a PTC protection circuit of the automobile air conditioner. The control device of the PTC auxiliary heating device comprises an acquisition unit configured to acquire standby parameters of the automobile air conditioner and acquire an on-off parameter of the PTC protection circuit in the case that the PTC auxiliary heating device does not start working after the automobile air conditioner is powered on; and a control unit configured to determine whether the direct current contactor is faulty according to the standby parameters of the automobile air conditioner, and determine whether the temperature protection module is faulty according to the on-off parameter of the PTC protection circuit. The control unit is further configured to determine that the automobile air conditioner can start and operate in a preset start mode in the case that the direct current contactor is determined to be not faulty, and initiate a prompt message that the direct current contactor is faulty in the case that the direct current contactor is determined to be faulty. The control unit is further configured to determine that the automobile air conditioner can operate in a preset electric auxiliary heating mode in the case that the temperature protection module is determined to be not faulty, and initiate a prompt message that the temperature protection module is faulty in the case that the temperature protection module is determined to be faulty.

[0013] In some embodiments, the automobile air conditioner has a main control board, a coil of the direct current contactor is connected to a first port of the main control board, a contact of the direct current contactor is connected between a power supply battery of the automobile air conditioner and the PTC heating body, standby parameters of the automobile air conditioner include an end voltage across the contact of the direct current contactor, and the control unit determines whether the direct current contactor has a fault according to the standby parameters of the automobile air conditioner, including determining whether the end voltage across the contact of the direct current contactor is a voltage of the power supply battery and determining whether the end voltage across the contact of the direct current contactor is 0, determining that the direct current contactor has no fault if it is determined that the end voltage across the contact of the direct current contactor is the voltage of the power supply battery, and determining that the contact of the direct current contactor is stuck, i.e., determining that the direct current contactor has a fault if it is determined that the end voltage across the contact of the direct current contactor is 0.

[0014] In some embodiments, the automobile air conditioner has a main control board, a coil of the direct current contactor is connected to a first port of the main control board, a contact of the direct current contactor is connected in the PTC power supply circuit, standby parameters of the automobile air conditioner further include a current value of the PTC power supply circuit, and the control unit determines whether the direct current contactor has a fault according to the standby parameters of the automobile air conditioner, further including determining whether the current value of the PTC power supply circuit is 0, determining that the direct current contactor has no fault if it is determined that the current value of the PTC power supply circuit is 0, and determining that the contact of the direct current contactor is stuck, i.e., determining that the direct current contactor has a fault if it is determined that the current value of the PTC power supply circuit is not 0.

[0015] In some embodiments, the automobile air conditioner has a main control board, a coil of the direct current contactor is connected to a first port of the main control board, a contact of the direct current contactor is connected in the PTC power supply circuit, standby parameters of the automobile air conditioner further include a current value of the PTC power supply circuit, and the control unit determines whether the direct current contactor has a fault according to the standby parameters of the automobile air conditioner, further including determining whether the current value of the PTC power supply circuit is 0, determining that the direct current contactor has no fault if it is determined that the current value of the PTC power supply circuit is 0, and determining that the contact of the direct current contactor is stuck, i.e., determining that the direct current contactor has a fault if it is determined that the current value of the PTC power supply circuit is not 0.

[0016] In some embodiments, the control unit determines whether the temperature protection module is faulty based on the on-off parameters of the PTC protection circuit, including: determining whether the PTC protection circuit is in an on state or an off state based on the on-off parameters of the PTC protection circuit; if it is determined that the PTC protection circuit is in an on state, it is determined that the temperature protection module is not faulty; if it is determined that the PTC protection circuit is in an off state, it is determined that the temperature protection module is disconnected, that is, it is determined that the temperature protection module is faulty.

[0017] In some embodiments, the control unit determines whether the temperature protection module has failed based on the on-off parameters of the PTC protection circuit, and further includes: if it is determined that the temperature protection module has not failed, after controlling the PTC auxiliary heating device to operate in the electric auxiliary heating mode of the automobile air conditioner, determining again based on the on-off parameters of the PTC protection circuit whether the PTC protection circuit is in the on state or the off state; if it is determined that the PTC protection circuit is in the on state, controlling the PTC auxiliary heating device to maintain the current operation; if it is determined that the PTC protection circuit is in the off state, controlling the PTC auxiliary heating device to stop working, and controlling the fan of the automobile air conditioner to start and run; after a set time, determining based on the on-off parameters of the PTC protection circuit whether the PTC protection circuit is in the restored on state or maintained in the off state; if it is determined that the PTC protection circuit is in the restored on state, determining that the temperature protection module has not failed; if it is determined that the PTC protection circuit is in the maintained off state, determining that the temperature protection module is disconnected and cannot be restored, that is, determining that the temperature protection module has failed.

[0018] In accordance with the above device, the present invention provides a car air conditioner on another aspect, comprising: a control device for the above-mentioned PTC auxiliary heating device.

[0019] In accordance with the above method, the present invention further provides a storage medium, which includes a stored program, wherein when the program is running, the device where the storage medium is located is controlled to execute the steps of the control method of the PTC auxiliary heating device described above.

[0020] In accordance with the above method, the present invention further provides a computer program product, comprising a computer program, which implements the steps of the above method for controlling a PTC auxiliary heating device when executed by a processor.

[0021] Therefore, the solution of the present invention is aimed at the PTC auxiliary heating device of the automobile air conditioner (such as Figure 8 The PTC auxiliary heating component 1 shown in FIG. 1 ) has a PTC heating element, a temperature limiter and a thermal fuse (such as Figure 8The PTC heating body 2, the temperature limiter 3 and the thermal fuse 4 shown in the figure are connected in the PTC power supply circuit power line of the automobile battery, and the PTC power supply circuit is controlled by the on-off of the DC contactor; in the standby state of the automobile air conditioner, the PTC auxiliary heating device stops working, the end voltage between the contacts of the DC contactor is detected, or the current value of the PTC power supply circuit is detected, or the temperature value detected by the temperature sensing bag at the main control board is detected, the DC contactor sticking is identified, the fan at the main control board is controlled to start cooling, and the display board connected with the main control board reports the fault code of the DC contactor sticking; in the standby state of the automobile air conditioner, the PTC auxiliary heating device stops working, the on-off state of the PTC component protection circuit signal feedback line is detected, when the temperature limiter or the thermal fuse is disconnected and cannot be restored, the display board connected with the main control board reports the fault code of the temperature limiter or the thermal fuse being disconnected and cannot being restored; in the working state of the PTC auxiliary heating device, the on-off state of the PTC component protection circuit signal feedback line is detected, when the temperature limiter or the thermal fuse is disconnected and cannot be restored, the PTC auxiliary heating device is controlled to stop working, and the fan at the main control board is controlled to run for a certain time: if the PTC component protection circuit signal feedback line is restored to be on, the PTC auxiliary heating device is controlled to run normally, if the PTC component protection circuit signal feedback line is not restored to be on, the display board connected with the main control board reports the fault code of the temperature limiter or the thermal fuse being disconnected and cannot being restored; thus, by identifying the DC contactor sticking fault and identifying the temperature limiter or the thermal fuse protection device disconnection fault, the protection measures are taken, the reliability and safety of the automobile air conditioner are improved, and the safety of the automobile is also improved.

[0022] Other features and advantages of the present application will be set forth in the following description, and in part will become apparent to those skilled in the art from the description, or can be learned by practice of the application.

[0023] The technical solutions of the present application will be further described in detail below with the help of the drawings and examples. BRIEF DESCRIPTION OF DRAWINGS

[0024] Figure 1 It is a flowchart of an embodiment of the control method of the PTC auxiliary heating device of the present application;

[0025] Figure 2 It is a flowchart of an embodiment of determining whether the DC contactor 5 fails according to the end voltage between the contacts of the DC contactor 5 in the method of the present application;

[0026] Figure 3 It is a flowchart of an embodiment of determining whether the DC contactor 5 fails according to the current value of the PTC power supply circuit in the method of the present application;

[0027] Figure 4 Flow chart for an embodiment of the method of the present application for determining whether the DC contactor 5 is faulty according to the detection value of the temperature sensor at the master control board 7;

[0028] Figure 5 Flow chart for an embodiment of the method of the present application for determining whether the temperature protection module is faulty when the PTC auxiliary heating device is not working;

[0029] Figure 6 Flow chart for an embodiment of the method of the present application for determining whether the temperature protection module is faulty when the PTC auxiliary heating device is working;

[0030] Figure 7 Structural diagram of an embodiment of the control device of the PTC auxiliary heating device of the present application;

[0031] Figure 8 Structural diagram of the overall structure of the air conditioner PTC auxiliary heating device control component of the present application;

[0032] Figure 9 Logic diagram of the voltage detection judgment of the present application;

[0033] Figure 10 Logic diagram of the current detection judgment of the present application;

[0034] Figure 11 Logic diagram of the temperature detection judgment of the present application;

[0035] Figure 12 Logic diagram of the protection circuit detection judgment of the present application.

[0036] In the embodiments of the present application, the reference signs in the accompanying drawings are as follows:

[0037] 1-PTC auxiliary heating component; 2-PTC heating body; 3-temperature limiter; 4-thermal fuse; 5-DC contactor; 6-fan; 7-master control board; 8-display board; 9-PTC power supply circuit power line; 10-PTC protection circuit signal feedback line; 11-DC contactor coil control lead; 12-temperature sensing bag; 13-master control board power line; 14-signal communication line; 102-acquisition unit; 104-control unit. DETAILED DESCRIPTION

[0038] In order to make the objects, technical solutions and advantages of the present application clearer, the technical solutions of the present application will be described below in connection with specific embodiments of the present application and corresponding drawings. Obviously, the described embodiments are only some of the embodiments of the present application, but not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative efforts fall within the scope of protection of the present application.

[0039] It is considered that the temperature limiter and thermal fuse protector of the PTC auxiliary heating device of the electric vehicle air conditioner are located in a low-voltage weak-electricity on-off signal feedback loop, and the PTC auxiliary heating device is powered by controlling the DC contactor. However, if the DC contactor is stuck or the temperature limiter or the thermal fuse protector fails to recover after being disconnected, the safety of the air conditioner and the vehicle will be affected. Specifically, once the DC contactor is stuck, the protection effect of the temperature limiter and the thermal fuse protector will be shielded, and the high-voltage power battery will continuously supply power to the PTC auxiliary heating device, resulting in dry burning of the PTC auxiliary heating device without wind, which may cause serious consequences such as air conditioner burning, even electric vehicle burning. Or the temperature limiter or the thermal fuse protector fails to recover after being disconnected, and the low-voltage weak-electricity protection loop feeds back a disconnection signal, thereby controlling the DC contactor to disconnect and stop supplying power to the PTC auxiliary heating device, resulting in poor heating effect of the air conditioner and causing customer complaints.

[0040] Therefore, the present application provides a control method of a PTC auxiliary heating device, specifically a control method of a PTC auxiliary heating device of an electric vehicle air conditioner, which identifies the sticking fault of the DC contactor and the disconnection fault of the temperature limiter or the thermal fuse protector, and then takes protective measures to prevent the PTC auxiliary heating device from dry burning without wind and to meet the working conditions of the PTC auxiliary heating device but not working, thereby improving the reliability and safety of the vehicle air conditioner and the safety of the vehicle.

[0041] According to an embodiment of the present application, a control method of a PTC auxiliary heating device is provided, as shown in Figure 1 The flowchart of an embodiment of the method of the present application. The control method of the PTC auxiliary heating device can be applied to a vehicle air conditioner; the PTC auxiliary heating device comprises a PTC heating body 2 and a temperature protection module, and the temperature protection module is as shown in Figure 8The temperature limiter 3 and the thermal fuse 4 are shown; the PTC auxiliary heating device 2 is located in a PTC power supply circuit of the automobile air conditioner, and a direct current contactor 5 is arranged at a power supply end of the PTC auxiliary heating device 2, specifically, the direct current contactor 5 is arranged between the PTC auxiliary heating device 2 and a power supply battery of the automobile air conditioner; the temperature protection module is located in a PTC protection circuit of the automobile air conditioner, specifically, the temperature protection module is located in a PTC protection circuit of a main control board 7 of the automobile air conditioner; specifically, the automobile air conditioner has the main control board 7, the direct current contactor 5, a fan 6 and the PTC auxiliary heating device; the PTC auxiliary heating device includes the PTC auxiliary heating device 2 and the temperature protection module, and the temperature protection module is as shown in Figure 8 The temperature limiter 3 and the thermal fuse 4 are shown; the direct current contactor 5 and the PTC auxiliary heating device are arranged in series in a PTC power supply circuit of a power supply battery of the automobile air conditioner; the temperature protection module is arranged in a PTC protection circuit of the main control board 7; and the fan 6 is connected to the main control board 7. In the scheme of the present application, as shown in Figure 1 The control method of the PTC auxiliary heating device includes steps S110 to S140.

[0042] In step S110, in the case that the PTC auxiliary heating device does not start working after the automobile air conditioner is powered on, standby parameters of the automobile air conditioner are acquired, and on-off parameters of the PTC protection circuit are acquired.

[0043] In step S120, whether the direct current contactor 5 is faulty is determined according to the standby parameters of the automobile air conditioner, and whether the temperature protection module is faulty is determined according to the on-off parameters of the PTC protection circuit.

[0044] In step S130, if it is determined that the direct current contactor 5 is not faulty, it is determined that the automobile air conditioner can start and run in a preset start mode; if it is determined that the direct current contactor 5 is faulty, it is determined that the automobile air conditioner cannot start and run in the preset start mode, the fan 6 of the automobile air conditioner is controlled to start and run, and a prompt message that the direct current contactor 5 is faulty is initiated.

[0045] In step S140, if it is determined that the temperature protection module is not faulty, it is determined that the automobile air conditioner can run in a preset electric auxiliary heating mode, that is, in the case that the automobile air conditioner starts and runs, the PTC auxiliary heating device can be controlled to run in the electric auxiliary heating mode of the automobile air conditioner; if it is determined that the temperature protection module is faulty, it is determined that the automobile air conditioner cannot run in the preset electric auxiliary heating mode, that is, in the case that the automobile air conditioner starts and runs, the PTC auxiliary heating device is not controlled to run in the electric auxiliary heating mode of the automobile air conditioner, and a prompt message that the temperature protection module is faulty is initiated.

[0046] The application provides a control scheme of a PTC auxiliary heating device of an electric vehicle air conditioner.

[0047] In some embodiments, the automobile air conditioner has a main control board 7, a coil of the DC contactor 5 is connected to a first port of the main control board 7, for example, a CN1 port of the main control board 7; in a PTC power supply circuit of the automobile air conditioner, contacts of the DC contactor 5 are connected between a power supply battery of the automobile air conditioner and the PTC heating body 2; standby parameters of the automobile air conditioner include an end voltage between the contacts of the DC contactor 5.

[0048] In step S120, whether the DC contactor 5 is faulty is determined according to the standby parameters of the automobile air conditioner, including the following process: whether the DC contactor 5 is faulty is determined according to the end voltage between the contacts of the DC contactor 5.

[0049] The application will be further described below with reference to the accompanying drawings. Figure 2 The application will be further described below with reference to the accompanying drawings.

[0050] In step S210, whether the end voltage between the contacts of the DC contactor 5 is the voltage of the power supply battery and whether the end voltage between the contacts of the DC contactor 5 is 0 are determined.

[0051] In step S220, if it is determined that the end voltage between the contacts of the DC contactor 5 is the voltage of the power supply battery, it is determined that the DC contactor 5 is not faulty, and it is determined that the automobile air conditioner can be started in a preset starting mode and run.

[0052] Step S230, if the end voltage of the contact of the DC contactor 5 is determined to be 0, it is determined that the contact of the DC contactor 5 is stuck, that is, it is determined that the DC contactor 5 is faulty, to determine that the automobile air conditioner cannot start and run in the preset starting mode, and to initiate a prompt message that the DC contactor 5 is faulty.

[0053] Figure 9 The logic diagram for voltage detection and judgment of the application is specifically Figure 9 The logic diagram for voltage detection and judgment of the DC contactor 5 sticking. When the battery power is just powered on, the whole machine is in standby state, and it can be judged that the PTC auxiliary heating component 1 is in stop working state. At this time, the end voltage of the wiring terminal A1, A2 of the contact of the DC contactor 5 is detected: if the end voltage is the battery supply voltage, it is determined that the DC contactor 5 is normal, and the air conditioner can run in the normal starting mode; if the end voltage is 0V, it is determined that the DC contactor 5 is stuck, at this time, the fan (i.e. fan motor) 6 is forced to run to dissipate heat, and the fault code is fed back to the display panel 8 at the same time, prompting to replace the DC contactor 5. In Figure 9 In the example shown, voltage detection needs to increase two connection lines connected to the wiring terminals A1, A2 of the contact of the DC contactor 5, which has a lower cost.

[0054] In some embodiments, the automobile air conditioner has a main control board 7, the coil of the DC contactor 5 is connected to the first port of the main control board 7, such as the CN1 port of the main control board 7; the contact of the DC contactor 5 is connected in the PTC power supply circuit; and the standby parameters of the automobile air conditioner further include the current value of the PTC power supply circuit.

[0055] In step S120, determining whether the DC contactor 5 is faulty according to the standby parameters of the automobile air conditioner further includes a process of determining whether the DC contactor 5 is faulty according to the current value of the PTC power supply circuit.

[0056] The following will be further described in combination with Figure 3 The embodiment flow diagram for determining whether the DC contactor 5 is faulty according to the current value of the PTC power supply circuit in the method of the application shown in the figure further illustrates the specific process of determining whether the DC contactor 5 is faulty according to the current value of the PTC power supply circuit in step S120, which includes steps S310 to S330.

[0057] Step S310, determining whether the current value of the PTC power supply circuit is 0.

[0058] Step S320, if it is determined that the current value of the PTC power supply circuit is 0, it is determined that the DC contactor 5 is not faulty, to determine that the automobile air conditioner can start and run in the preset starting mode.

[0059] If the current value of the PTC power supply circuit is determined to be not 0, it is determined that the contact of the DC contactor 5 is stuck, i.e., it is determined that the DC contactor 5 is faulty, so as to determine that the automobile air conditioner cannot start and run in the preset starting mode, and a prompt message that the DC contactor 5 is faulty is initiated.

[0060] Figure 10 The logic diagram for the current detection judgment of the application is specifically Figure 10 The logic diagram for the current detection judgment of the DC contactor 5 is shown in the figure. When the battery power is just powered on, the whole machine is in standby state, and it can be judged that the PTC auxiliary heating component 1 is in stop working state. At this time, the current value of the PTC component power supply circuit power line 9 is detected: if no current is detected, it is determined that the DC contactor 5 is normal, and the air conditioner can run in the normal starting mode; if there is current, it is determined that the DC contactor 5 is stuck, at this time, the fan (i.e. fan motor) 6 is forced to run to dissipate heat, and the fault code is fed back to the display panel 8 at the same time, prompting to replace the DC contactor 5. In Figure 12 In the example shown, current detection requires the addition of a current transformer.

[0061] In some embodiments, the automobile air conditioner has a main control board 7, and a temperature sensor such as a temperature sensing bag 12 is arranged at the main control board 7; the standby parameters of the automobile air conditioner further include the detection value of the temperature sensor at the main control board 7.

[0062] In step S120, according to the standby parameters of the automobile air conditioner, it is determined whether the DC contactor 5 is faulty, which further includes the process of determining whether the DC contactor 5 is faulty according to the detection value of the temperature sensor at the main control board 7.

[0063] The following will be described in detail with reference to the specific embodiments of the application. Figure 4 The embodiment flow diagram for determining whether the DC contactor 5 is faulty according to the detection value of the temperature sensor at the main control board 7 in the method of the application is shown in the figure, which further illustrates the specific process of determining whether the DC contactor 5 is faulty according to the detection value of the temperature sensor at the main control board 7 in step S120, which includes steps S410 to S430.

[0064] In step S410, it is determined whether the detection value of the temperature sensor at the main control board 7 is within the set normal temperature range, and whether the detection value of the temperature sensor at the main control board 7 is higher than the set temperature threshold value; wherein the set normal temperature range is, for example, a normal temperature range, and the set temperature threshold value is, for example, a set temperature determination value.

[0065] In step S420, if it is determined that the detection value of the temperature sensor at the main control board 7 is within the set normal temperature range, it is determined that the DC contactor 5 is not faulty, so as to ensure that the automobile air conditioner can be started and operated according to the preset startup mode.

[0066] In step S430, if it is determined that the detection value of the temperature sensor at the main control board 7 is not within the set normal temperature range, and it is determined that the detection value of the temperature sensor at the main control board 7 is higher than the set temperature threshold, it is determined that the contacts of the DC contactor 5 are stuck, that is, it is determined that the DC contactor 5 has failed, so as to determine that the automobile air conditioner cannot be started and operated according to the preset startup mode, and a reminder message of the failure of the DC contactor 5 is initiated.

[0067] Figure 11 This is a logic diagram of the temperature detection and judgment of the present invention, specifically Figure 11 This is a logical diagram for temperature detection to determine if the DC contactor 5 is stuck. When the air conditioner is in standby mode, it can be determined that the PTC auxiliary heating component 1 is in a stopped working state. At this time, the temperature value of the temperature sensing package 12 (i.e., the indoor environment temperature sensing package of the air conditioner) is detected: if the temperature detected by the temperature sensing package 12 is normal temperature (room temperature), the DC contactor 5 is judged to be normal and can be operated in the normal start-up mode of the air conditioner; if the temperature detected by the temperature sensing package 12 is higher than the set temperature judgment value, the DC contactor 5 is judged to be stuck, and the fan (i.e., fan motor) 6 is forced to run to dissipate heat, and the synchronous feedback display panel 8 reports a fault code, prompting a replacement of the DC contactor 5. Figure 11 In the example shown, the temperature detection can be performed directly using the temperature sensing package 12 without increasing the cost. The set temperature judgment value is greater than the normal temperature (room temperature).

[0068] Figure 8 Schematic diagram of the overall structure of the control components of the air conditioner PTC auxiliary heating device of the present invention. Figure 8As shown, the positive and negative connection lines of the low-voltage power line 13 of the electric vehicle battery are connected to the main control board 7; the main control board 7 is connected to the display board 8 through the signal communication line 14. The main control board 7 has CN1 port, CN2 port, CN3 port and CN4 port. The CN1 port is connected to the coil control end of the DC contactor 5; the CN2 port is connected to the PTC protection circuit; the CN3 port is connected to the indoor environment temperature sensing bag 12; and the CN4 port is connected to the cooling fan 6. The PTC auxiliary heating device, such as the PTC auxiliary heating component 1, comprises a PTC heating body 2, a temperature limiter 3 and a thermal fuse 4. The positive connection line of the PTC power supply circuit power line 9 of the electric vehicle battery is connected to the positive connection end +A1 of the contact of the DC contactor 5; the negative connection end -A2 of the contact of the DC contactor 5 is connected to the negative connection line of the PTC power supply circuit power line 9 of the electric vehicle battery through the PTC heating body 2. The CN1 port of the main control board 7 is connected to the coil of the DC contactor 5 through the DC contactor coil control wire 11. The CN2 port of the main control board 7 is connected to the temperature limiter 3 and the thermal fuse 4 arranged in series through the PTC protection circuit signal feedback line 10. The CN3 port of the main control board 7 is connected to the temperature sensing bag 12. The CN4 port of the main control board 7 is connected to the fan (i.e. fan motor) 6. Figure 8 As shown in the example, the control logic for identifying and determining the sticking fault of the DC contactor is provided, and the control logic for identifying and determining the disconnection and non-recovery fault of the temperature limiter or thermal fuse protector is provided.

[0069] The scheme of the application relates to the technical field of PTC auxiliary heating device control of electric vehicle air conditioner. In related schemes, under the premise of meeting the working condition of starting the PTC auxiliary heating device, the working instruction of the PTC auxiliary heating device is output through the CN1 port of the main control board 7, the contact of the direct current contactor 5 is controlled to be attracted, the A1 and A2 wiring terminals are controlled to be conducted, so that the battery power supplies power to the PTC heating body 2, and the PTC auxiliary heating component 1 works. When the stop working condition of the PTC auxiliary heating device is met, the stop working instruction of the PTC auxiliary heating device is output through the CN1 port of the main control board 7, the contact of the direct current contactor 5 is controlled to be disconnected, the A1 and A2 wiring terminals are controlled to be disconnected, so that the battery power stops supplying power to the PTC heating body 2, and the PTC auxiliary heating component 1 stops working. The stop working condition of the PTC auxiliary heating component 1 includes that the ring temperature detected by the temperature sensing bag 12 reaches the set temperature, the motor of the fan (i.e. the fan motor) 6 stops running, the temperature limiter 3 and the thermal fuse 4 are disconnected due to high temperature, and the like. The disadvantage of these schemes is that once the A1 and A2 wiring terminals of the contact of the direct current contactor 5 are adhered, even if the stop working condition of the PTC auxiliary heating device is met, the stop working instruction of the PTC auxiliary heating component 1 is output through the CN1 port of the main control board 7, the A1 and A2 wiring terminals of the contact of the direct current contactor 5 cannot be disconnected, so that the battery power supplies power to the PTC heating body 2, and the PTC auxiliary heating component 1 continuously works, which is prone to cause the dry burning of the PTC auxiliary heating component 1 without wind, and the air conditioner may even catch fire, and even the electric vehicle may catch fire. The related schemes do not have the control logic for detecting the adhesion of the terminals of the direct current contactor 5, and do not have subsequent protection measures. The scheme of the application adds three identification modes of the adhesion fault of the direct current contactor, and then takes protection measures to forcibly start the fan (i.e. the fan motor) 6 to run and dissipate heat, and synchronously displays the fault code warning on the display panel (such as the display panel 8) to remind timely maintenance and replacement of the direct current contactor 5, so that the dry burning of the PTC auxiliary heating component 1 without wind is avoided.

[0070] In related schemes, only when the temperature limiter 3 and the thermal fuse 4 of the protection circuit are disconnected due to high temperature reaching the action temperature, the PTC auxiliary heating component 1 stops working, and when the temperature decreases to the recovery temperature, the temperature limiter 3 is restored to be conducted to restart the PTC auxiliary heating component 1. The disadvantage of these schemes is that once the temperature limiter 3 fails and cannot be restored to be conducted after being disconnected, and the thermal fuse 4 is disconnected, even if the starting running condition of the PTC auxiliary heating component 1 is met, the PTC auxiliary heating component 1 cannot work. The scheme of the application adds a mode of identifying that the temperature limiter 3 or the thermal fuse 4 fails and cannot be restored after being disconnected, so that the display panel (such as the display panel 8) displays the fault code warning to remind timely maintenance and replacement of the faulty temperature limiter 3 or the thermal fuse 4, and the phenomenon that the PTC auxiliary heating component 1 does not work although the working condition is met is avoided, so that the heating effect of the air conditioner is not good.

[0071] In the solution of the present invention, whether a DC contactor supplying power to the PTC auxiliary heating device has a sticking fault is identified through three methods: current detection, voltage detection, and temperature detection. After the DC contactor sticking fault is identified, the fan is forced to start running to dissipate heat, and a fault code warning is displayed on the display panel simultaneously, prompting timely repair and replacement of the DC contactor, thereby preventing the PTC auxiliary heating device from drying out without air, thereby improving the safety of the car air conditioner and the safety of the car.

[0072] In the solution of the present invention, the three detection methods—voltage, current, and temperature—are independent, and any one of them can identify a DC contactor adhesion fault. Using them all together would only result in a waste of cost. These three detection methods can identify DC contactor adhesion, enabling forced fan operation for heat dissipation. They can also identify disconnected and unrecoverable temperature limiters or thermal fuses, prompting prompt repair and replacement of the faulty parts. This improves the reliability and safety of the vehicle's air conditioner, as well as the safety of the vehicle itself.

[0073] The solution of the present invention is based on the control solution of the PTC auxiliary heating device of the electric vehicle air conditioner in the related solution, and adds control logic for identifying and judging the adhesion fault of the DC contactor that controls the power supply circuit of the PTC auxiliary heating component. Through three methods such as detecting voltage, detecting current, and detecting temperature, the adhesion fault of the DC contactor is identified and judged, and then protective measures are taken to force the fan to start running for heat dissipation, and the fault code warning is displayed on the panel synchronously to remind timely repair and replacement of the DC contactor, thereby achieving the purpose of eliminating the phenomenon of dry burning of the PTC auxiliary heating device without air; a method is added to identify the fault of the temperature limiter or thermal fuse protector being disconnected and not restored, so that the fault code warning is displayed on the panel to remind timely repair and replacement of the faulty temperature limiter or thermal fuse protector, thereby avoiding the phenomenon that the PTC auxiliary heating device meets the working conditions but does not work, resulting in poor air conditioning heating effect.

[0074] In some embodiments, determining whether the temperature protection module is faulty based on the on / off parameters of the PTC protection circuit in step S120 includes: determining whether the temperature protection module is faulty when the PTC auxiliary heating device is not working.

[0075] The following combination Figure 5 The figure shows a flow chart of an embodiment of determining whether the temperature protection module is faulty when the PTC auxiliary heating device is not working in the method of the present invention, further illustrating the specific process of determining whether the temperature protection module is faulty when the PTC auxiliary heating device is not working in step S120, including: steps S510 to S530.

[0076] Step S510, according to the on-off parameter of the PTC protection circuit, determine whether the PTC protection circuit is in the on state or the off state.

[0077] Step S520, if it is determined that the PTC protection circuit is in the on state, it is determined that the temperature protection module does not have a fault, so as to determine that the automobile air conditioner can operate in the preset electric auxiliary heating mode, that is, in the case that the automobile air conditioner is turned on and operates, the PTC auxiliary heating device can be controlled to operate in the electric auxiliary heating mode of the automobile air conditioner.

[0078] Step S530, if it is determined that the PTC protection circuit is in the off state, it is determined that the temperature protection module is off, that is, it is determined that the temperature protection module has a fault, so as to determine that the automobile air conditioner cannot operate in the preset electric auxiliary heating mode, that is, in the case that the automobile air conditioner is turned on and operates, the PTC auxiliary heating device is not controlled to operate in the electric auxiliary heating mode of the automobile air conditioner, and a prompt message that the temperature protection module has a fault is initiated.

[0079] Figure 12 The logic diagram for the protection circuit detection and judgment of the present application is specifically Figure 12 The logic diagram for the protection circuit detection and judgment of the present application is specifically When the battery power is just powered on, the whole machine is in a standby state, and it can be judged that the PTC auxiliary heating component 1 is in a stopped working state. At this time, the on-off state of the PTC component protection circuit signal feedback line 10 is detected to detect the on-off state of the PTC component protection circuit: if the PTC component protection circuit signal feedback line 10 is turned on, it is judged that the temperature limiter 3 and the thermal fuse 4 are normal, and the air conditioner can operate in the normal auxiliary heating mode; if the PTC component protection circuit signal feedback line 10 is off at this time, it is judged that the temperature limiter 3 or the thermal fuse 4 has a fault and cannot be restored, and the display panel 8 feeds back a fault code to prompt the replacement of the temperature limiter 3 or the thermal fuse 4. The temperature limiter is a recoverable device, which should be turned on at standby normal temperature; if it is in the off state at this time, it is that there is a foreign object stuck or structural deformation, and it cannot be restored to turn on. The thermal fuse is a one-time device, which will not restore to turn on after being off.

[0080] In the scheme of the present application, whether the temperature limiter or the thermal fuse protector has a disconnection fault is identified, that is, whether the temperature limiter or the thermal fuse protector is disconnected and not restored. After identifying that the temperature limiter or the thermal fuse protector has a disconnection and non-recovery fault, the display panel feeds back a fault code warning to remind timely maintenance and replacement of the fault temperature limiter or thermal fuse protector, so as to eliminate the phenomenon that the PTC auxiliary heating device meets the working conditions but does not work, and improve the reliability of the automobile air conditioner.

[0081] The scheme of the application, in the control scheme of the PTC auxiliary heating device of the electric vehicle air conditioner, the control logic for identifying and judging the sticking fault of the DC contactor is added, the sticking fault of the DC contactor for supplying power to the PTC auxiliary heating device is identified through three ways, and then the control method of forcibly starting the fan to run for heat dissipation, synchronously displaying the fault code alarm of the panel, reminding timely maintenance and replacement of the DC contactor is reminded; and a way is added to identify the disconnection of the temperature limiter or thermal fuse protector without recovery fault, so as to display the fault code alarm of the panel, reminding timely maintenance and replacement of the fault temperature limiter or thermal fuse protector. By adopting this control method, the sticking fault of the DC contactor can be identified and found, and timely maintenance can be performed to avoid the adverse consequences of air conditioner burning and even electric vehicle burning, so as to achieve the effect of protecting the air conditioner, and at the same time, the running work caused by the sticking conduction of the DC contactor when the PTC auxiliary heating device does not need to start running can be reduced, the power consumption can be reduced, and the vehicle endurance can be improved; and the disconnection of the temperature limiter or thermal fuse protector without recovery fault can be identified and found, and timely maintenance can be performed to avoid the adverse consequences of the PTC auxiliary heating device meeting the working conditions but not working, resulting in poor heating effect of the air conditioner and causing customer complaints.

[0082] In some embodiments, the step S120 of determining whether the temperature protection module fails according to the on-off parameter of the PTC protection circuit further comprises: a process of determining whether the temperature protection module fails in the case that the PTC auxiliary heating device works.

[0083] The specific process of determining whether the temperature protection module fails in the case that the PTC auxiliary heating device works in the method of the application will be further described below with reference to the embodiment flowchart of determining whether the temperature protection module fails in the case that the PTC auxiliary heating device works in the method of the application shown in FIG. 6. Figure 6 The specific process of determining whether the temperature protection module fails in the case that the PTC auxiliary heating device works in the method of the application will be further described below with reference to the embodiment flowchart of determining whether the temperature protection module fails in the case that the PTC auxiliary heating device works in the method of the application shown in FIG. 6.

[0084] In the case that it is determined that the temperature protection module does not fail, the PTC auxiliary heating device is controlled to run in the electric auxiliary heating mode of the vehicle air conditioner, and then the on-off parameter of the PTC protection circuit is determined again to determine whether the PTC protection circuit is in the on state or the off state.

[0085] In the case that it is determined that the temperature protection module does not fail, the PTC auxiliary heating device is controlled to run in the electric auxiliary heating mode of the vehicle air conditioner, and then the on-off parameter of the PTC protection circuit is determined again to determine whether the PTC protection circuit is in the on state or the off state.

[0086] Step S630, if it is determined that the PTC protection circuit is in the off state, the PTC auxiliary heating device is controlled to stop working, and the fan 6 of the automobile air conditioner is controlled to start and run; after a set time, it is determined whether the PTC protection circuit is in the recovery on state or the maintain off state according to the on-off parameters of the PTC protection circuit. In the scheme of the application, the logic of the control scheme increases the detection of the abnormality of the DC contactor contact adhesion; after identifying the adhesion of the DC contactor, the fan is forced to start running for heat dissipation, and the display panel is simultaneously displayed with a fault code warning to remind timely maintenance and replacement of the DC contactor. The logic of the control scheme also increases the detection of whether the temperature limiter or thermal fuse is in the non-recoverable abnormality of disconnection; after identifying the disconnection of the temperature limiter or thermal fuse protector that cannot be recovered, the display panel is simultaneously displayed with a fault code warning to remind timely maintenance and replacement of the faulty temperature limiter or thermal fuse protector.

[0087] Step S640, if it is determined that the PTC protection circuit is in the recovery on state, it is determined that the temperature protection module has no fault, so that it is determined that the automobile air conditioner can run in the preset electric auxiliary heating mode, that is, in the case that the automobile air conditioner is started and runs, the PTC auxiliary heating device can be controlled to run in the electric auxiliary heating mode of the automobile air conditioner.

[0088] Step S650, if it is determined that the PTC protection circuit is in the maintain off state, it is determined that the temperature protection module is disconnected and cannot be recovered, that is, it is determined that the temperature protection module has a fault, so that it is determined that the automobile air conditioner cannot run in the preset electric auxiliary heating mode, that is, in the case that the automobile air conditioner is started and runs, the PTC auxiliary heating device is not controlled to run in the electric auxiliary heating mode of the automobile air conditioner, and a prompt message that the temperature protection module has a fault is initiated.

[0089] Referring to Figure 12 In the example shown, if the PTC auxiliary heating component 1 is in the working process, the PTC component protection circuit signal feedback line 10 feeds back the off signal to stop the PTC auxiliary heating component 1, then the fan (i.e. the fan motor) 6 is ensured to continuously run for 5 minutes, and then the on-off state of the PTC component protection circuit signal feedback line 10 is detected again: if the PTC component protection circuit signal feedback line 10 recovers to the on state, it is judged that the temperature limiter 3 and the thermal fuse 4 are normal, and the air conditioner can run in the normal auxiliary heating mode; if the PTC component protection circuit signal feedback line 10 maintains the off state, it is judged that the temperature limiter 3 or the thermal fuse 4 is faulty and disconnected, and cannot be recovered, and the display panel 8 feeds back a fault code to prompt replacement of the temperature limiter 3 or the thermal fuse 4. Figure 12 In the example shown, no additional cost is required, only logical judgment is required.

[0090] In the scheme of the present application, the sticking fault of the DC contactor can be identified, and timely maintenance can be performed to avoid the adverse consequences of air conditioner burning and even electric vehicle burning, thereby achieving the effect of protecting the air conditioner. At the same time, the running work caused by the sticking conduction of the DC contactor when the PTC auxiliary heating device does not need to be started can be reduced, the power consumption can be reduced, and the vehicle endurance can be improved. The disconnection of the temperature limiter or thermal fuse protector that cannot be restored can also be identified, and timely maintenance can be performed to avoid the situation that the PTC auxiliary heating device meets the working conditions but does not work, which leads to poor heating effect of the air conditioner and causes customer complaints.

[0091] The scheme of the present application adds control logic for identifying and judging the sticking fault of the DC contactor in the control scheme of the PTC auxiliary heating device of the electric vehicle air conditioner in the related scheme, and then takes protective measures to forcibly start the fan to dissipate heat, and synchronously displays the fault code warning on the panel to remind timely maintenance and replacement of the DC contactor, thereby achieving the purpose of preventing the PTC auxiliary heating device from being dry-burned without wind. At the same time, control logic for identifying and judging the disconnection of the temperature limiter or thermal fuse protector that cannot be restored is added, and the fault code warning is synchronously displayed on the panel to remind timely maintenance and replacement of the temperature limiter or thermal fuse, thereby avoiding the situation that the PTC auxiliary heating device meets the working conditions but does not work, which leads to poor heating effect of the air conditioner and causes customer complaints.

[0092] In the scheme of the present application, the sticking of the DC contactor is detected: control logic for identifying and judging the sticking fault of the DC contactor is added, and three methods are used to identify the sticking fault of the DC contactor that supplies power to the PTC auxiliary heating device; sticking protection measures: the fan is forcibly started to dissipate heat, and the fault code warning is synchronously displayed on the panel to remind timely maintenance and replacement of the DC contactor. Whether the temperature limiter or thermal fuse is disconnected and cannot be restored is detected: control logic for identifying and judging the disconnection of the temperature limiter or thermal fuse protector that cannot be restored is added, and this method is used to identify the disconnection fault of the temperature limiter or thermal fuse protector that cannot be restored. However, the present application is not limited to the above four identification and judgment methods, and other detection and identification schemes can also use the scheme of the present application.

[0093] The technical scheme of the present embodiment is used for the PTC auxiliary heating device of the automobile air conditioner (such as a PTC auxiliary heating component 1 as shown in Figure 8 The PTC auxiliary heating device has a PTC heating body, a temperature limiter, and a thermal fuse (such as a PTC auxiliary heating component 2 as shown in Figure 8The PTC heater 2, temperature limiter 3 and thermal fuse 4 shown in the figure, the PTC heater is connected to the PTC power supply circuit power line of the car battery, and the on and off of the PTC power supply circuit is controlled by the DC contactor, the temperature limiter and the thermal fuse are connected in series in the PTC protection circuit signal feedback line of the main control board of the car air conditioner; in the standby state of the car air conditioner, the PTC auxiliary heating device stops working, detects the terminal voltage at both ends of the contact of the DC contactor or detects the current value of the PTC power supply circuit or detects the temperature value detected by the temperature sensing package at the main control board, and controls the fan at the main control board to start heat dissipation after identifying that the DC contactor is sticking, and reports the fault code of the DC contactor sticking through the display board connected to the main control board; in the standby state of the car air conditioner, the PTC auxiliary heating device stops working, detects the on and off state of the PTC component protection circuit signal feedback line, and judges that the temperature limiter or thermal fuse is disconnected and there is no When the temperature cannot be restored, a fault code indicating that the temperature limiter or thermal fuse is disconnected and cannot be restored is reported through the display board connected to the main control board; when the PTC auxiliary heating device is working, the on-off state of the signal feedback line of the PTC component protection circuit is detected. When it is determined that the temperature limiter or thermal fuse is disconnected and cannot be restored, the PTC auxiliary heating device is controlled to stop working, and the fan at the main control board is controlled to run for a certain period of time: if the signal feedback line of the PTC component protection circuit is restored, the PTC auxiliary heating device is controlled to operate normally; if the signal feedback line of the PTC component protection circuit is not restored, a fault code indicating that the temperature limiter or thermal fuse is disconnected and cannot be restored is reported through the display board connected to the main control board; thus, by identifying the DC contactor adhesion fault and the temperature limiter or thermal fuse protector disconnection fault, protective measures are taken, thereby improving the reliability and safety of the automobile air conditioner, and also improving the safety of the automobile.

[0094] According to an embodiment of the present invention, a control device for a PTC auxiliary heating device corresponding to the control method for the PTC auxiliary heating device is also provided. Figure 7 The structure diagram of an embodiment of the device of the present invention is shown in FIG. The control device of the PTC auxiliary heating device can be applied to automobile air conditioners; the PTC auxiliary heating device includes: a PTC heating element 2 and a temperature protection module, the temperature protection module is as follows: Figure 8 The temperature limiter 3 and thermal fuse 4 shown; the PTC heater 2 is located in the PTC power supply circuit of the automobile air conditioner, and a DC contactor 5 is provided at the power supply end of the PTC heater 2, specifically, a DC contactor 5 is provided between the PTC heater 2 and the power supply battery of the automobile air conditioner; the temperature protection module is located in the PTC protection circuit of the automobile air conditioner, specifically, the temperature protection module is located in the PTC protection circuit of the main control board 7 of the automobile air conditioner; specifically, the automobile air conditioner has a main control board 7, a DC contactor 5, a fan 6 and the PTC auxiliary heating device; the PTC auxiliary heating device includes: a PTC heater 2, and a temperature protection module, the temperature protection module is as shownFigure 8 The temperature limiter 3 and the thermal fuse 4; the DC contactor 5 and the PTC heating module, which are arranged in series in the PTC power supply circuit of the power supply battery of the automobile air conditioner; the temperature protection module, which is arranged in the PTC protection circuit of the main control board 7; and the fan 6 connected with the main control board 7. In the scheme of the present application, as shown in the figure, Figure 7 The control device of the PTC auxiliary heating device comprises an acquisition unit 102 and a control unit 104.

[0095] The acquisition unit 102 is configured to acquire standby parameters of the automobile air conditioner and on-off parameters of the PTC protection circuit in the case that the PTC auxiliary heating device does not start working after the automobile air conditioner is powered on. The specific functions and processes of the acquisition unit 102 are described in step S110.

[0096] The control unit 104 is configured to determine whether the DC contactor 5 fails according to the standby parameters of the automobile air conditioner and to determine whether the temperature protection module fails according to the on-off parameters of the PTC protection circuit. The specific functions and processes of the control unit 104 are described in step S120.

[0097] The control unit 104 is further configured to determine that the automobile air conditioner can start and run in the preset start mode if it is determined that the DC contactor 5 does not fail and to determine that the automobile air conditioner cannot start and run in the preset start mode if it is determined that the DC contactor 5 fails, control the fan 6 of the automobile air conditioner to start and run, and initiate a reminder message that the DC contactor 5 fails. The specific functions and processes of the control unit 104 are described in step S130.

[0098] The control unit 104 is further configured to determine that the automobile air conditioner can run in the preset electric auxiliary heating mode if it is determined that the temperature protection module does not fail, that is, the PTC auxiliary heating device can be controlled to run in the electric auxiliary heating mode of the automobile air conditioner in the case that the automobile air conditioner starts and runs, and to determine that the automobile air conditioner cannot run in the preset electric auxiliary heating mode if it is determined that the temperature protection module fails, that is, the PTC auxiliary heating device is not controlled to run in the electric auxiliary heating mode of the automobile air conditioner in the case that the automobile air conditioner starts and runs, and initiate a reminder message that the temperature protection module fails. The specific functions and processes of the control unit 104 are described in step S140.

[0099] The scheme of the application provides a control scheme of a PTC auxiliary heating device of an electric vehicle air conditioner. After the adhesion failure of the DC contactor for supplying power to the PTC auxiliary heating device is identified through three ways, the fan is forcibly started to dissipate heat, and the display panel displays the fault code warning to prevent the PTC auxiliary heating device from being dry-burned without wind. In addition, after the disconnection failure (i.e. disconnection without recovery) of the temperature limiter or thermal fuse protector is identified through one way, the display panel displays the fault code warning to prevent the failure of the PTC auxiliary heating device under the working condition but not working, thereby improving the reliability and safety of the automobile air conditioner and the safety of the automobile.

[0100] In some embodiments, the automobile air conditioner has a main control board 7, the coil of the DC contactor 5 is connected to the first port of the main control board 7, such as the CN1 port of the main control board 7, the contact of the DC contactor 5 is connected between the power supply battery of the automobile air conditioner and the PTC heating body 2, and the standby parameters of the automobile air conditioner include the terminal voltage between the contacts of the DC contactor 5.

[0101] The control unit 104 determines whether the DC contactor 5 fails according to the standby parameters of the automobile air conditioner, including the process of determining whether the DC contactor 5 fails according to the terminal voltage between the contacts of the DC contactor 5, which is specifically as follows:

[0102] The control unit 104 is specifically further configured to determine whether the terminal voltage between the contacts of the DC contactor 5 is the voltage of the power supply battery and whether the terminal voltage between the contacts of the DC contactor 5 is 0. The specific functions and processes of the control unit 104 are described in step S210.

[0103] The control unit 104 is specifically further configured to determine that the DC contactor 5 does not fail if it is determined that the terminal voltage between the contacts of the DC contactor 5 is the voltage of the power supply battery, so as to determine that the automobile air conditioner can start and run in the preset start mode. The specific functions and processes of the control unit 104 are described in step S220.

[0104] The control unit 104 is specifically further configured to determine that the contacts of the DC contactor 5 are stuck if it is determined that the terminal voltage between the contacts of the DC contactor 5 is 0, i.e. to determine that the DC contactor 5 fails, so as to determine that the automobile air conditioner cannot start and run in the preset start mode, and to initiate the reminder message that the DC contactor 5 fails. The specific functions and processes of the control unit 104 are described in step S230.

[0105] Figure 9 The logic diagram for voltage detection and judgment of the application is specifically Figure 9The logic diagram for voltage detection to determine the sticking of the DC contactor 5. When the battery power is just powered on, the whole machine is in standby state, and it can be determined that the PTC auxiliary heating component 1 is in stop working state. At this time, the end voltage of the connection terminal A1, A2 of the contact of the DC contactor 5 is detected: if the end voltage is the battery supply voltage, it is determined that the DC contactor 5 is normal, and the air conditioner can be operated in the normal start mode; if the end voltage is 0V, it is determined that the DC contactor 5 is stuck, at this time, the fan (i.e. fan motor) 6 is forced to run to dissipate heat, and the synchronous feedback display panel 8 reports a fault code to prompt the replacement of the DC contactor 5. In Figure 9 In the example shown, voltage detection needs to increase two connection lines connected to the connection terminal A1, A2 of the contact of the DC contactor 5, which has a lower cost.

[0106] In some embodiments, the automobile air conditioner has a main control panel 7, the coil of the DC contactor 5 is connected to the first port of the main control panel 7, such as the CN1 port of the main control panel 7; the contact of the DC contactor 5 is connected in the PTC power supply circuit; the standby parameters of the automobile air conditioner further include the current value of the PTC power supply circuit.

[0107] The control unit 104 determines whether the DC contactor 5 fails according to the standby parameters of the automobile air conditioner, and further includes a process of determining whether the DC contactor 5 fails according to the current value of the PTC power supply circuit, specifically as follows:

[0108] The control unit 104 is specifically further configured to determine whether the current value of the PTC power supply circuit is 0. The specific functions and processes of the control unit 104 are described with reference to step S310.

[0109] The control unit 104 is specifically further configured to determine that the DC contactor 5 does not fail if it is determined that the current value of the PTC power supply circuit is 0, so as to determine that the automobile air conditioner can start and operate in the preset start mode. The specific functions and processes of the control unit 104 are described with reference to step S320.

[0110] The control unit 104 is specifically further configured to determine that the contact of the DC contactor 5 is stuck if it is determined that the current value of the PTC power supply circuit is not 0, that is, to determine that the DC contactor 5 fails, so as to determine that the automobile air conditioner cannot start and operate in the preset start mode, and to initiate a prompt message that the DC contactor 5 fails. The specific functions and processes of the control unit 104 are described with reference to step S330.

[0111] Figure 10 The logic diagram for current detection to determine the sticking of the DC contactor 5, specifically Figure 10The logic diagram for judging the sticking of the DC contactor 5 by current detection. When the battery power is just powered on, the whole machine is in standby state, and it can be judged that the PTC auxiliary heating component 1 is in stop working state. At this time, the current value of the PTC component power supply loop power line 9 is detected: if no current is detected, it is judged that the DC contactor 5 is normal, and the air conditioner can be operated in the normal start mode; if there is current, it is judged that the DC contactor 5 is stuck, at this time, the forced fan (i.e. fan motor) 6 is operated to dissipate heat, and the synchronous feedback display panel 8 reports a fault code to prompt the replacement of the DC contactor 5. In Figure 12 In the example shown, current detection requires the addition of a current transformer.

[0112] In some embodiments, the automobile air conditioner has a main control board 7, and a temperature sensor such as a temperature sensing bag 12 is arranged at the main control board 7; the standby parameters of the automobile air conditioner further include the detection value of the temperature sensor at the main control board 7.

[0113] The control unit 104 determines whether the DC contactor 5 fails according to the standby parameters of the automobile air conditioner, and further includes a process of determining whether the DC contactor 5 fails according to the detection value of the temperature sensor at the main control board 7, specifically as follows:

[0114] The control unit 104 is specifically further configured to determine whether the detection value of the temperature sensor at the main control board 7 is within a set normal temperature range, and determine whether the detection value of the temperature sensor at the main control board 7 is higher than a set temperature threshold; wherein the set normal temperature range is, for example, a normal temperature range. For specific functions and processing of the control unit 104, see step S410.

[0115] The control unit 104 is specifically further configured to determine that the DC contactor 5 does not fail if it is determined that the detection value of the temperature sensor at the main control board 7 is within the set normal temperature range, so as to determine that the automobile air conditioner can start and operate in the preset start mode. For specific functions and processing of the control unit 104, see step S420.

[0116] The control unit 104 is specifically further configured to determine that the contact of the DC contactor 5 is stuck, i.e. determine that the DC contactor 5 fails, if it is determined that the detection value of the temperature sensor at the main control board 7 is not within the set normal temperature range and the detection value of the temperature sensor at the main control board 7 is higher than the set temperature threshold, so as to determine that the automobile air conditioner cannot start and operate in the preset start mode, and initiate a prompt message that the DC contactor 5 fails. For specific functions and processing of the control unit 104, see step S430.

[0117] Figure 11 The logic diagram for temperature detection and judgment of the present application is specificallyFigure 11 The logic diagram for temperature detection to determine the sticking of the direct current contactor 5. When the air conditioner is in standby state, it can be determined that the PTC auxiliary heating component 1 is in stop working state. At this time, the temperature value of the temperature sensing bag 12 is detected: if the temperature sensing bag 12 detects the temperature as normal temperature (room temperature), it is determined that the direct current contactor 5 is normal, and the air conditioner can be operated in normal start mode; if the temperature detected by the temperature sensing bag 12 is higher than the set temperature determination value, it is determined that the direct current contactor 5 is stuck, at which time the fan (i.e. fan motor) 6 is forced to run to dissipate heat, and the display panel 8 is fed back with fault code at the same time, prompting to replace the direct current contactor 5. In Figure 11 In the example shown, temperature detection can directly use the temperature sensing bag 12 without increasing cost.

[0118] Figure 8 The overall structure diagram of the control component of the air conditioner PTC auxiliary heating device of the application is shown. As Figure 8 shown, the positive and negative connection lines of the low-voltage power supply line 13 of the electric vehicle battery are connected to the main control panel 7; the main panel 7 is connected to the display panel 8 through the signal communication line 14. The main control panel 7 has CN1 port, CN2 port, CN3 port and CN4 port. The PTC auxiliary heating device such as the PTC auxiliary heating component 1 includes: PTC heating body 2, temperature limiter 3 and thermal fuse 4. The positive connection line of the PTC power supply loop power supply line 9 of the electric vehicle battery is connected to the positive connection end +A1 of the contact of the direct current contactor 5; the negative connection end -A2 of the contact of the direct current contactor 5 is connected to the negative connection line of the PTC power supply loop power supply line 9 of the electric vehicle battery after passing through the PTC heating body 2. The CN1 port of the main control panel 7 is connected to the coil of the direct current contactor 5 through the direct current contactor coil control wire 11. The CN2 port of the main control panel 7 is connected to the temperature limiter 3 and the thermal fuse 4 arranged in series through the PTC protection loop signal feedback line 10. The CN3 port of the main control panel 7 is connected to the temperature sensing bag 12. The CN4 port of the main control panel 7 is connected to the fan (i.e. fan motor) 6. Figure 8 In the example shown, the control logic for identifying and determining the sticking fault of the direct current contactor is provided, and the control logic for identifying and determining the disconnection of the temperature limiter or thermal fuse protector without recovery fault is provided.

[0119] The scheme of the application relates to the technical field of PTC auxiliary heating device control of electric vehicle air conditioner. In related schemes, under the premise of meeting the working condition of starting the PTC auxiliary heating device, the working instruction of the PTC auxiliary heating device is output through the CN1 port of the main control board 7, the contact of the direct current contactor 5 is controlled to be attracted, the A1 and A2 wiring terminals are controlled to be conducted, so that the battery power supplies power to the PTC heating body 2, and the PTC auxiliary heating component 1 works. When the stop working condition of the PTC auxiliary heating device is met, the stop working instruction of the PTC auxiliary heating device is output through the CN1 port of the main control board 7, the contact of the direct current contactor 5 is controlled to be disconnected, the A1 and A2 wiring terminals are controlled to be disconnected, so that the battery power stops supplying power to the PTC heating body 2, and the PTC auxiliary heating component 1 stops working. The stop working condition of the PTC auxiliary heating component 1 includes that the ring temperature detected by the temperature sensing bag 12 reaches the set temperature, the motor of the fan (i.e. the fan motor) 6 stops running, the temperature limiter 3 and the thermal fuse 4 are disconnected due to high temperature, and the like. The disadvantage of these schemes is that once the A1 and A2 wiring terminals of the contact of the direct current contactor 5 are adhered, even if the stop working condition of the PTC auxiliary heating device is met, the stop working instruction of the PTC auxiliary heating component 1 is output through the CN1 port of the main control board 7, the A1 and A2 wiring terminals of the contact of the direct current contactor 5 cannot be disconnected, so that the battery power supplies power to the PTC heating body 2, and the PTC auxiliary heating component 1 continuously works, which is prone to cause the dry burning of the PTC auxiliary heating component 1 without wind, and the air conditioner may even catch fire, and even the electric vehicle may catch fire. The related schemes do not have the control logic for detecting the adhesion of the terminals of the direct current contactor 5, and do not have subsequent protection measures. The scheme of the application adds three identification modes of the adhesion fault of the direct current contactor, and then takes protection measures to forcibly start the fan (i.e. the fan motor) 6 to run and dissipate heat, and synchronously displays the fault code warning on the display panel (such as the display panel 8) to remind timely maintenance and replacement of the direct current contactor 5, so that the dry burning of the PTC auxiliary heating component 1 without wind is avoided.

[0120] In related schemes, only when the temperature limiter 3 and the thermal fuse 4 of the protection circuit are disconnected due to high temperature reaching the action temperature, the PTC auxiliary heating component 1 stops working, and when the temperature decreases to the recovery temperature, the temperature limiter 3 is restored to be conducted to restart the PTC auxiliary heating component 1. The disadvantage of these schemes is that once the temperature limiter 3 fails and cannot be restored to be conducted after being disconnected, and the thermal fuse 4 is disconnected, even if the starting running condition of the PTC auxiliary heating component 1 is met, the PTC auxiliary heating component 1 cannot work. The scheme of the application adds a mode of identifying that the temperature limiter 3 or the thermal fuse 4 fails and cannot be restored after being disconnected, so that the display panel (such as the display panel 8) displays the fault code warning to remind timely maintenance and replacement of the faulty temperature limiter 3 or the thermal fuse 4, and the phenomenon that the PTC auxiliary heating component 1 meets the working condition but does not work is avoided, so that the heating effect of the air conditioner is not good.

[0121] In the scheme of the present application, whether the DC contactor for supplying power to the PTC auxiliary heating device has a sticking fault is identified through three ways of judging by detecting current, judging by detecting voltage, judging by detecting temperature: after identifying the sticking fault of the DC contactor, forcibly starting the operation of the fan for heat dissipation, synchronously displaying the fault code on the panel to warn timely maintenance and replacement of the DC contactor, preventing the dry burning of the PTC auxiliary heating device without wind, and improving the safety of the automobile air conditioner and the safety of the automobile.

[0122] In the scheme of the present application, the three ways of detecting voltage, detecting current, and detecting temperature are independent, and any one way can identify the sticking fault of the DC contactor. If all three ways are used together, it will only cause cost waste. Through the three detection methods, the sticking of the DC contactor is identified, and then the forced opening of the fan for heat dissipation is taken; and the disconnection of the temperature limiter or thermal fuse protector without recovery of the fault is identified, timely maintenance and replacement of the faulty part are reminded, the reliability and safety of the automobile air conditioner are improved, and the safety of the automobile is also improved.

[0123] In the scheme of the present application, on the basis of the control scheme of the PTC auxiliary heating device of the electric vehicle air conditioner in the related scheme, the control logic for identifying and judging the sticking fault of the DC contactor of the PTC auxiliary heating component power supply circuit is added, the sticking fault of the DC contactor is identified and judged through three methods of detecting voltage, detecting current, and detecting temperature, and then protective measures are taken, the fan is forcibly started to operate for heat dissipation, the fault code is displayed on the synchronous display panel to warn timely maintenance and replacement of the DC contactor, the purpose of preventing the dry burning of the PTC auxiliary heating device without wind is achieved; a way is added to identify the disconnection of the temperature limiter or thermal fuse protector without recovery of the fault, so that the fault code is displayed on the display panel to warn timely maintenance and replacement of the faulty temperature limiter or thermal fuse protector, and the phenomenon that the PTC auxiliary heating device meets the working conditions but does not work, resulting in poor heating effect of the air conditioner, is avoided.

[0124] In some embodiments, the control unit 104 determines whether the temperature protection module has a fault according to the on-off parameters of the PTC protection circuit, including: a process of determining whether the temperature protection module has a fault in the case that the PTC auxiliary heating device does not work, which is specifically as follows:

[0125] The control unit 104 is specifically further configured to determine whether the PTC protection circuit is in a conduction state or a disconnected state according to the on-off parameters of the PTC protection circuit. For specific functions and processing of the control unit 104, see step S510.

[0126] The control unit 104 is further configured to determine that the temperature protection module is not faulty if it is determined that the PTC protection circuit is in the on state, so as to determine that the automobile air conditioner can operate in the preset electric auxiliary heating mode, that is, the PTC auxiliary heating device can be controlled to operate in the electric auxiliary heating mode of the automobile air conditioner under the condition that the automobile air conditioner is turned on and operates. For specific functions and processing of the control unit 104, see step S520.

[0127] The control unit 104 is further configured to determine that the temperature protection module is disconnected if it is determined that the PTC protection circuit is in the off state, that is, to determine that the temperature protection module is faulty, so as to determine that the automobile air conditioner cannot operate in the preset electric auxiliary heating mode, that is, the PTC auxiliary heating device is not controlled to operate in the electric auxiliary heating mode of the automobile air conditioner under the condition that the automobile air conditioner is turned on and operates, and a prompt message is initiated to indicate that the temperature protection module is faulty. For specific functions and processing of the control unit 104, see step S530.

[0128] Figure 12 The logic diagram for the protection circuit detection and judgment of the present application is specifically Figure 12 The logic diagram for the protection circuit detection and judgment of the present application is specifically When the battery power is just powered on, the whole machine is in a standby state, and it can be determined that the PTC auxiliary heating component 1 is in a stopped working state. At this time, the on-off state of the PTC component protection circuit signal feedback line 10 is detected: if the PTC component protection circuit signal feedback line 10 is turned on, it is determined that the temperature limiter 3 and the thermal fuse 4 are normal, and the air conditioner can operate in the normal auxiliary heating mode; if the PTC component protection circuit signal feedback line 10 is disconnected at this time, it is determined that the temperature limiter 3 or the thermal fuse 4 is faulty and cannot be restored, and the display panel 8 feeds back a fault code to prompt replacement of the temperature limiter 3 or the thermal fuse 4.

[0129] In the scheme of the present application, whether the temperature limiter or the thermal fuse protector is disconnected and not restored is identified, that is, whether the temperature limiter or the thermal fuse protector is disconnected and not restored is identified. After identifying that the temperature limiter or the thermal fuse protector is disconnected and not restored, the display panel displays a fault code warning to remind timely maintenance and replacement of the faulty temperature limiter or thermal fuse protector, so as to eliminate the phenomenon that the PTC auxiliary heating device meets the working conditions but does not work, and improve the reliability of the automobile air conditioner.

[0130] The scheme of the present application, in the control scheme of the PTC auxiliary heating device of the electric vehicle air conditioner, increases the control logic for identifying and judging the sticking fault of the DC contactor. Through three ways, the sticking fault of the DC contactor for supplying power to the PTC auxiliary heating device is identified, and then the fan is forcibly started to run for heat dissipation, and the display panel displays the fault code warning to remind timely maintenance and replacement of the DC contactor. In addition, a way is added to identify the disconnection of the temperature limiter or thermal fuse protector without recovery fault, so that the display panel displays the fault code warning to remind timely maintenance and replacement of the fault temperature limiter or thermal fuse protector. By using this control method, the sticking fault of the DC contactor can be identified and found for timely maintenance, avoiding the adverse consequences of air conditioner burning and even electric vehicle burning, achieving the effect of protecting the air conditioner, and reducing the running work caused by the sticking of the DC contactor when the PTC auxiliary heating device does not need to start, reducing power consumption and improving the vehicle endurance. In addition, the disconnection of the temperature limiter or thermal fuse protector without recovery fault can be identified and found for timely maintenance, avoiding the adverse consequences of the PTC auxiliary heating device meeting the working conditions but not working, resulting in poor heating effect of the air conditioner and causing customer complaints.

[0131] In some embodiments, the control unit 104 determines whether the temperature protection module has a fault according to the on-off parameter of the PTC protection circuit, and further comprises a process of determining whether the temperature protection module has a fault in the case that the PTC auxiliary heating device is working, which is specifically as follows:

[0132] The control unit 104 is specifically further configured to, in the case that it is determined that the temperature protection module has no fault, control the PTC auxiliary heating device to run in the electric auxiliary heating mode of the automobile air conditioner, and then determine whether the PTC protection circuit is in the on state or the off state according to the on-off parameter of the PTC protection circuit again. For the specific functions and processes of the control unit 104, see step S610.

[0133] The control unit 104 is specifically further configured to, if it is determined that the PTC protection circuit is in the on state, control the PTC auxiliary heating device to maintain the current running. For the specific functions and processes of the control unit 104, see step S620.

[0134] The control unit 104 is further configured to control the PTC auxiliary heating device to stop working and control the fan 6 of the automobile air conditioner to start and run if it is determined that the PTC protection circuit is in the off state; and determine whether the PTC protection circuit is in the recovery on state or the maintained off state according to the on-off parameters of the PTC protection circuit after a set time. The specific functions and processing of the control unit 104 are described with reference to step S630. In the scheme of the present application, the control scheme is logically increased to detect the abnormality of the DC contactor contact adhesion; after recognizing the DC contactor adhesion, the fan is forced to start and run for heat dissipation, and the display panel is synchronously displayed with a fault code warning to remind timely maintenance and replacement of the DC contactor. The control scheme is also logically increased to detect whether the temperature limiter or thermal fuse is in the off state and cannot be recovered; after recognizing that the temperature limiter or thermal fuse protector is in the off state and cannot be recovered, the display panel is synchronously displayed with a fault code warning to remind timely maintenance and replacement of the faulty temperature limiter or thermal fuse protector.

[0135] The control unit 104 is further configured to determine that the temperature protection module is not faulty if it is determined that the PTC protection circuit is in the recovery on state, so as to determine that the automobile air conditioner can run in the preset electric auxiliary heating mode, i.e., the PTC auxiliary heating device can be controlled to run in the electric auxiliary heating mode of the automobile air conditioner under the condition that the automobile air conditioner is started and runs. The specific functions and processing of the control unit 104 are described with reference to step S640.

[0136] The control unit 104 is further configured to determine that the temperature protection module is off and cannot be recovered if it is determined that the PTC protection circuit is in the maintained off state, i.e., determine that the temperature protection module is faulty, so as to determine that the automobile air conditioner cannot run in the preset electric auxiliary heating mode, i.e., the PTC auxiliary heating device is not controlled to run in the electric auxiliary heating mode of the automobile air conditioner under the condition that the automobile air conditioner is started and runs, and a reminder message that the temperature protection module is faulty is initiated. The specific functions and processing of the control unit 104 are described with reference to step S650.

[0137] Referring to Figure 12 In the example shown, if the PTC auxiliary heating component 1 is in the working process, the PTC component protection circuit signal feedback line 10 feeds back the off signal to stop the PTC auxiliary heating component 1, then the fan (i.e., the fan motor) 6 is ensured to continuously run for 5 minutes, and the on-off state of the PTC component protection circuit signal feedback line 10 is detected again: if the PTC component protection circuit signal feedback line 10 recovers to the on state, it is judged that the temperature limiter 3 and the thermal fuse 4 are normal, and the air conditioner can run in the normal auxiliary heating mode; if the PTC component protection circuit signal feedback line 10 maintains the off state, it is judged that the temperature limiter 3 or the thermal fuse 4 is faulty and off and cannot be recovered, and the display panel 8 feeds back the fault code to prompt replacement of the temperature limiter 3 or the thermal fuse 4.Figure 12 In the example shown, only logic judgment needs to be added without increasing cost.

[0138] In the scheme of the application, the DC contactor sticking fault can be identified and repaired in time to avoid the adverse consequences of air conditioner burning and even electric vehicle burning, thereby achieving the effect of protecting the air conditioner; meanwhile, the running work caused by the DC contactor sticking conduction when the PTC auxiliary heating device does not need to be started can be reduced, the power consumption is reduced, and the vehicle endurance is improved. The temperature limiter or thermal fuse protector disconnection fault that cannot be recovered can also be identified and repaired in time to avoid the situation that the PTC auxiliary heating device meets the working condition but does not work, which leads to poor heating effect of the air conditioner and causes customer complaints.

[0139] The scheme of the application adds the control logic for identifying and judging the DC contactor sticking fault in the control scheme of the electric vehicle air conditioner PTC auxiliary heating device in the related scheme, and then takes protective measures to forcibly start the fan to dissipate heat, and synchronously displays the fault code warning on the panel to remind timely maintenance and replacement of the DC contactor, so as to achieve the purpose of preventing the PTC auxiliary heating device from being dry-burned without wind. Meanwhile, the control logic for identifying and judging the temperature limiter or thermal fuse protector disconnection fault that cannot be recovered is added, and the fault code warning is synchronously displayed on the panel to remind timely maintenance and replacement of the temperature limiter or thermal fuse, so as to avoid the situation that the PTC auxiliary heating device meets the working condition but does not work, which leads to poor heating effect of the air conditioner and causes customer complaints.

[0140] In the scheme of the application, the DC contactor sticking fault is detected: the control logic for identifying and judging the DC contactor sticking fault is added, and three methods are used to identify the sticking fault of the DC contactor that supplies power to the PTC auxiliary heating device; the sticking protection measure: the fan is forcibly started to dissipate heat, and the fault code warning is synchronously displayed on the panel to remind timely maintenance and replacement of the DC contactor. Whether the temperature limiter or thermal fuse is disconnected and cannot be recovered is detected: the control logic for identifying and judging the temperature limiter or thermal fuse protector disconnection fault that cannot be recovered is added, and this method is used to identify the disconnection fault of the temperature limiter or thermal fuse protector that cannot be recovered.

[0141] Since the processing and functions realized by the device of the embodiment basically correspond to the embodiments, principles and examples of the foregoing method, details not described in the description of the embodiment can be referred to the related description in the foregoing embodiments, which will not be described herein.

[0142] According to the embodiment of the application, an automobile air conditioner corresponding to the control device of the PTC auxiliary heating device is also provided. The automobile air conditioner can include the control device of the PTC auxiliary heating device described above.

[0143] Since the processing and functions realized by the automobile air conditioner of the embodiment basically correspond to the embodiments, principles and examples of the foregoing device, the description of the embodiment does not describe the related descriptions in the foregoing embodiments in detail, and will not be described here.

[0144] According to the embodiment of the present application, a computer program product corresponding to the control method of the PTC auxiliary heating device is also provided, comprising a computer program which, when executed by a processor, realizes the steps of the control method of the PTC auxiliary heating device described above.

[0145] Since the processing and functions realized by the product of the embodiment basically correspond to the embodiments, principles and examples of the foregoing method, the description of the embodiment does not describe the related descriptions in the foregoing embodiments in detail, and will not be described here.

[0146] According to the embodiment of the present application, a storage medium corresponding to the control method of the PTC auxiliary heating device is also provided, comprising a stored program, wherein when the program is running, the device where the storage medium is located executes the steps of the control method of the PTC auxiliary heating device described above.

[0147] Since the processing and functions realized by the storage medium of the embodiment basically correspond to the embodiments, principles and examples of the foregoing method, the description of the embodiment does not describe the related descriptions in the foregoing embodiments in detail, and will not be described here.

[0148] In summary, those skilled in the art can easily understand that the above-mentioned advantageous modes can be freely combined and superimposed without conflict.

[0149] The above only describes the embodiments of the present application and is not used to limit the present application. Those skilled in the art can make various modifications and changes to the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principles of the present application shall be included in the scope of the claims of the present application.

Claims

1. A control method for a PTC auxiliary heating device, characterized in that: The invention can be applied to automobile air conditioners; the PTC auxiliary heating device comprises: a PTC heating element (2) and a temperature protection module; the PTC heating element (2) is located in the PTC power supply circuit of the automobile air conditioner, and a DC contactor (5) is provided at the power supply end of the PTC heating element (2); the temperature protection module is located in the PTC protection circuit of the automobile air conditioner; and a control method of the PTC auxiliary heating device comprises: When the PTC auxiliary heating device does not start working after the automobile air conditioner is powered on, obtaining the standby parameters of the automobile air conditioner and the on / off parameters of the PTC protection circuit; Determining whether the DC contactor (5) is faulty based on the standby parameters of the automobile air conditioner; and determining whether the temperature protection module is faulty based on the on / off parameters of the PTC protection circuit; If it is determined that the DC contactor (5) has not failed, then it is determined that the automobile air conditioner can be started and operated according to a preset startup mode; if it is determined that the DC contactor (5) has failed, then a reminder message indicating that the DC contactor (5) has failed is issued; If it is determined that the temperature protection module is not faulty, it is determined that the automobile air conditioner can operate in the preset electric auxiliary heating mode; if it is determined that the temperature protection module is faulty, a reminder message indicating that the temperature protection module is faulty is initiated.

2. The control method of the PTC auxiliary heating device according to claim 1, characterized in that: The automobile air conditioner has a main control board (7); the coil of the DC contactor (5) is connected to a first port of the main control board (7); the contacts of the DC contactor (5) are connected between a power supply battery of the automobile air conditioner and the PTC heating element (2); the standby parameters of the automobile air conditioner include: terminal voltages at both ends of the contacts of the DC contactor (5); Determining whether the DC contactor (5) is faulty based on the standby parameters of the automobile air conditioner comprises: Determining whether the terminal voltage across the contacts of the DC contactor (5) is the voltage of the power supply battery, and determining whether the terminal voltage across the contacts of the DC contactor (5) is 0; If it is determined that the terminal voltages at both ends of the contacts of the DC contactor (5) are the voltage of the power supply battery, it is determined that the DC contactor (5) has not failed; If it is determined that the terminal voltages at both ends of the contacts of the DC contactor (5) are 0, it is determined that the contacts of the DC contactor (5) are adhered, that is, it is determined that the DC contactor (5) has a fault.

3. The control method of the PTC auxiliary heating device according to claim 1, characterized in that: The automobile air conditioner has a main control board (7), the coil of the DC contactor (5) is connected to the first port of the main control board (7); the contact of the DC contactor (5) is connected to the PTC power supply circuit; the standby parameters of the automobile air conditioner also include: the current value of the PTC power supply circuit; Determining whether the DC contactor (5) is faulty based on the standby parameters of the automobile air conditioner, further comprising: Determine whether the current value of the PTC power supply circuit is 0; If it is determined that the current value of the PTC power supply circuit is 0, it is determined that the DC contactor (5) has not failed; If it is determined that the current value of the PTC power supply circuit is not 0, it is determined that the contacts of the DC contactor (5) are adhered, that is, it is determined that the DC contactor (5) has a fault.

4. The control method of the PTC auxiliary heating device according to claim 1, characterized in that: The automobile air conditioner has a main control board (7), and a temperature sensor is provided on the main control board (7); the standby parameter of the automobile air conditioner also includes: a detection value of the temperature sensor on the main control board (7); Determining whether the DC contactor (5) is faulty based on the standby parameters of the automobile air conditioner, further comprising: Determining whether a detection value of a temperature sensor at the main control board (7) is within a set normal temperature range, and determining whether a detection value of the temperature sensor at the main control board (7) is higher than a set temperature threshold; If it is determined that the detection value of the temperature sensor at the main control board (7) is within the set normal temperature range, it is determined that the DC contactor (5) has not failed; If it is determined that the detection value of the temperature sensor at the main control board (7) is not within the set normal temperature range, and it is determined that the detection value of the temperature sensor at the main control board (7) is higher than the set temperature threshold, it is determined that the contacts of the DC contactor (5) are stuck, that is, it is determined that the DC contactor (5) has a fault.

5. The control method of the PTC auxiliary heating device according to any one of claims 1 to 4, characterized in that: Determining whether the temperature protection module fails according to the on-off parameters of the PTC protection circuit includes: determining whether the PTC protection circuit is in an on state or an off state according to an on-off parameter of the PTC protection circuit; If it is determined that the PTC protection circuit is in a conducting state, it is determined that the temperature protection module has not failed; If it is determined that the PTC protection circuit is in a disconnected state, it is determined that the temperature protection module is disconnected, that is, it is determined that the temperature protection module is faulty.

6. The control method of the PTC auxiliary heating device according to claim 5, characterized in that: Determining whether the temperature protection module fails according to the on-off parameters of the PTC protection circuit, further comprising: When it is determined that the temperature protection module has not failed, after controlling the PTC auxiliary heating device to operate in the electric auxiliary heating mode of the automobile air conditioner, determining again based on the on / off parameters of the PTC protection circuit whether the PTC protection circuit is in an on state or an off state; If it is determined that the PTC protection circuit is in the on state, controlling the PTC auxiliary heating device to maintain the current operation; If it is determined that the PTC protection circuit is in the disconnected state, the PTC auxiliary heating device is controlled to stop working, and the fan (6) of the automobile air conditioner is controlled to start and run; after a set time, according to the on-off parameter of the PTC protection circuit, it is determined whether the PTC protection circuit is in the restored on state or maintained in the disconnected state; If it is determined that the PTC protection circuit is in a restored conductive state, it is determined that the temperature protection module has not failed; If it is determined that the PTC protection circuit is in a maintained disconnected state, it is determined that the temperature protection module is disconnected and cannot be restored, that is, it is determined that the temperature protection module is faulty.

7. A control device for a PTC auxiliary heating device, characterized in that: The invention can be applied to automobile air conditioners; the PTC auxiliary heating device comprises: a PTC heating element (2) and a temperature protection module; the PTC heating element (2) is located in the PTC power supply circuit of the automobile air conditioner, and a DC contactor (5) is provided at the power supply end of the PTC heating element (2); the temperature protection module is located in the PTC protection circuit of the automobile air conditioner; the control device of the PTC auxiliary heating device comprises: an acquiring unit configured to acquire a standby parameter of the automobile air conditioner and an on / off parameter of the PTC protection circuit when the PTC auxiliary heating device does not start working after the automobile air conditioner is powered on; A control unit is configured to determine whether the DC contactor (5) is faulty based on the standby parameters of the automobile air conditioner; and to determine whether the temperature protection module is faulty based on the on / off parameters of the PTC protection circuit; The control unit is further configured to, if it is determined that the DC contactor (5) has not failed, determine that the automobile air conditioner can be started and operated according to a preset startup mode; if it is determined that the DC contactor (5) has failed, initiate a reminder message indicating that the DC contactor (5) has failed; The control unit is further configured to, if it is determined that the temperature protection module is not faulty, determine that the automobile air conditioner can operate in a preset electric auxiliary heating mode; if it is determined that the temperature protection module is faulty, initiate a reminder message indicating that the temperature protection module is faulty.

8. An automobile air conditioner, characterized in that: include: The control device of the PTC auxiliary heating device according to claim 7.

9. A storage medium, characterized in that: The storage medium includes a stored program, wherein when the program is running, the device where the storage medium is located is controlled to execute the control method of the PTC auxiliary heating device according to any one of claims 1 to 6.

10. A computer program product comprising a computer program, characterized in that When the computer program is executed by a processor, the steps of the control method of the PTC auxiliary heating device according to any one of claims 1 to 6 are implemented.

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