Fault processing method for electronic oil pump of new energy automobile

Abstract

The invention relates to a new energy automobile electronic oil pump fault processing method. According to the method, different oil pump fault levels are defined, input signals are received and processed, preconditions of various oil pump faults are calculated, whether the current oil pump fault meets the preconditions or not is judged, whether the current oil pump fault meets a certain fault frequency threshold value or not is judged, and the torque limit value of the current oil pump fault level is calculated. And the recovery condition of the current oil pump fault level is calculated, and the motor torque is limited or recovered. According to the method, real-time protection can be provided for the motor of the new energy automobile, motor damage caused by over-temperature of the motor is prevented, the service life of the motor, the service life of the controller and the service life of the speed reducer are prolonged, and the service life of the new energy automobile is prolonged.

Description

Technical Field

[0001] The present application relates to the technical field of electronic oil pumps for new energy vehicles, and in particular to a method for handling faults of electronic oil pumps for new energy vehicles. Background Art

[0002] The electronic oil pump is a key component in new energy vehicles. It is responsible for promoting the circulation of cooling oil between the motor and the cooling system. The motor of a new energy vehicle removes the heat generated inside the motor through this oil circulation to keep the motor working within an efficient and stable temperature range, thereby extending the service life of the motor and the entire new energy vehicle. In addition, while the electronic oil pump is responsible for oil circulation, it can also lubricate the motor and reducer to prevent damage to the motor or reducer or other faults. The operating condition of the oil pump itself has a huge impact on the operating condition of the motor system of new energy vehicles.

[0003] However, in actual operation, the electronic oil pump of an automobile may have a variety of faults. In the prior art, there are few explanations and analyses on the fault handling methods of the electronic oil pump of new energy automobiles, which are insufficient and lack real-time protection for the motor of new energy automobiles.

[0004] When the electronic oil pump of a new energy vehicle fails, if it is not handled promptly and effectively, the electronic oil pump will not be able to sufficiently cool the motor and controller and lubricate the reducer, causing damage to components in the motor and controller due to overheating. For example, the motor controller overheats and becomes unable to control the motor speed; it cannot sufficiently lubricate the reducer gears, causing gear wear; and increasing the life of the motor, controller, and reducer. Summary of the invention

[0005] The purpose of the present invention is to solve the problems existing in the prior art and provide a method for handling the fault of an electronic oil pump of a new energy vehicle, by defining different oil pump fault levels, receiving and processing input signals, calculating the preconditions of various oil pump faults, judging whether the current oil pump fault meets the preconditions, judging whether the current oil pump fault meets a certain fault number threshold, calculating the torque limit value of the current oil pump fault level, calculating the recovery condition of the current oil pump fault level, limiting the motor torque or restoring the motor torque. The method for handling the fault of an electronic oil pump of a new energy vehicle described in the present invention can provide real-time protection for the motor of a new energy vehicle.

[0006] The technical solution of the present invention is achieved in this way: A method for handling a fault of an electronic oil pump of a new energy vehicle comprises the following steps: Step 1: Receive and process the electronic oil pump signal The received electronic oil pump signal includes an original fault signal of the electronic oil pump and an operation signal of the electronic oil pump; The processed electronic oil pump signal is a signal indicating an oil pump speed response fault when the difference between the speed requested by the oil pump controller and the actual speed of the oil pump is greater than a speed difference threshold and the duration reaches a certain time threshold; Step 2: Define different oil pump failure levels Different fault levels are defined according to different oil pump fault types. Faults that do not affect motor performance are defined as level 1 faults, faults that affect motor cooling performance are defined as level 2 faults, and faults that cause the oil pump to stop rotating are defined as level 3 faults. The oil pump fault includes the original fault reported by the original fault signal of the electronic oil pump and the oil pump speed response fault reported after the processing in step 1; Step 3: Calculate the preconditions for different oil pump failures The preconditions for the oil pump overload warning, oil pump stall fault, and oil pump speed response fault are that the oil pump temperature is greater than the temperature threshold or the oil pump speed is greater than the speed threshold; the preconditions for other oil pump faults are that the vehicle power-on signal flag is satisfied; Step 4: Determine whether the current oil pump fault meets the precondition of the oil pump fault calculated in step 3; if so, proceed to step 5; if not, return to step 3; Step 5: Define the fault confirmation time threshold and fault triggering number threshold; Step 6: Determine whether a fault has occurred based on whether the fault confirmation time threshold or fault triggering number threshold is met There are two situations to judge whether a fault has occurred. If one of the following situations is met, the fault is confirmed to have occurred: The duration of the current oil pump fault reaches the fault confirmation time threshold; or the number of fault triggering times in a driving cycle reaches the fault triggering times threshold; If the fault is confirmed to have occurred, proceed to step 7; if the fault is not confirmed to have occurred, return to step 5; Step 7: Calculate the motor torque limit value for the current oil pump failure The motor torque limit value of the current oil pump fault is calculated according to the different oil pump fault levels defined in step 2. When the fault is level 1, no motor torque limit is performed; when the fault is level 2, a certain motor torque limit is performed; when the fault is level 3, the motor torque is limited to 0; Step 8: Calculate the recovery conditions of the current oil pump failure Calculate the recovery condition of the current oil pump fault based on the different oil pump fault levels defined in step 2: The recovery conditions for level 1 and level 2 faults are as follows: The oil pump fault signal stops; Or the number of fault triggering times of the current oil pump fault in one driving cycle is less than a certain fault number threshold; The recovery condition for the level 3 fault is to re-energize the vehicle; Step 9: Determine whether the current oil pump fault meets the recovery condition calculated in step 8; if so, proceed to step 11; if not, proceed to step 10; Step 10: limit the motor torque according to the motor torque limit value of the current oil pump fault calculated in step 7, and return to step 9; Step 11: Restore the motor torque; release the limit on the motor torque.

[0007] Preferably, in step 1, the original fault signal of the electronic oil pump includes: oil pump overvoltage fault, oil pump undervoltage fault, oil pump overtemperature shutdown fault, oil pump current fault, oil pump self-test fault, oil pump overtemperature derating warning, oil pump communication fault, oil pump stall fault, oil pump overload warning; the operation signal of the electronic oil pump includes: actual speed of the oil pump, requested speed of the oil pump, temperature of the motor oil pump, etc.; Preferably, in step 1, when the oil pump cold start is unsuccessful, no oil pump overload warning, oil pump jam fault, or oil pump response fault detection is performed.

[0008] Preferably, the level 1 fault in step 2 includes: oil pump self-test fault, oil pump over-temperature derating warning; The second level faults include: oil pump overload warning, oil pump speed response fault, oil pump overpressure fault, and oil pump underpressure fault; The three levels of faults include: oil pump over-temperature shutdown fault, oil pump current fault, oil pump communication fault, and oil pump jam fault.

[0009] Preferably, in step 6 and step 8, the method for calculating the number of fault triggering times is: if a fault occurs once within a certain period of time, the number of faults is increased by one; if no fault occurs within a certain period of time, the number of faults is decreased by one.

[0010] Preferably, in step 7, the motor torque is limited to a certain extent, specifically limiting the motor torque limit value to half of the rated torque of the motor.

[0011] Preferably, in step 10, the level 1 fault and the level 2 fault are based on the torque limit value obtained in step 7, and the maximum operating power of the motor torque is limited by limiting the output performance of the motor. The level 3 fault needs to determine whether the current motor speed is greater than the short-circuit threshold. If it is greater than the short-circuit threshold, the electronic oil pump enters active short-circuit protection. If it is less than the short-circuit threshold, the electronic oil pump enters an open-circuit working state.

[0012] The above scheme is adopted to define different oil pump fault levels, receive and process input signals, calculate the preconditions of various oil pump faults, judge whether the current oil pump fault meets the preconditions, and judge whether the fault occurs, so as to prevent the fault from being falsely triggered due to signal interference and other reasons, calculate the torque limit value of the current oil pump fault level, calculate the recovery condition of the current oil pump fault level, and limit the motor torque to prevent the motor failure and damage caused by the electronic oil pump fault if the recovery condition is not met, and restore the motor torque in time when the recovery condition is met. By judging whether the fault occurs, false triggering of the fault caused by signal interference and other reasons is prevented. When the electronic oil pump fails, targeted measures are taken in time for different faults at the early stage of the fault to regulate the torque of the motor. By continuously receiving the signal of the electronic oil pump, analyzing the signal, eliminating false triggering, and regulating the motor torque in time, the motor is protected in real time. Prevent motor damage caused by motor overheating, extend the life of the motor, controller, and reducer, and increase the service life of new energy vehicles. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a flow chart of the present invention. DETAILED DESCRIPTION

[0014] See also Figure 1 The troubleshooting method for the electronic oil pump of new energy vehicles includes the following steps: Step 1: Receive and process the electronic oil pump signal The received electronic oil pump signal includes an original fault signal of the electronic oil pump and an operation signal of the electronic oil pump; the original fault signal of the electronic oil pump includes: oil pump overvoltage fault, oil pump undervoltage fault, oil pump overtemperature shutdown fault, oil pump current fault, oil pump self-test fault, oil pump overtemperature derating warning, oil pump communication fault, oil pump stall fault, oil pump overload warning; the operation signal of the electronic oil pump includes: actual speed of the oil pump, requested speed of the oil pump, motor oil pump temperature, etc.; The processed electronic oil pump signal is an oil pump speed response fault reported when the difference between the oil pump controller requested speed and the actual oil pump speed is greater than the speed difference threshold and the duration reaches a certain time threshold; for example, the speed difference threshold is set to 1000 revolutions per minute and the time threshold is set to 1 minute in this embodiment.

[0015] When the oil pump fails to start cold, no oil pump overload warning, oil pump jam fault, or oil pump response fault detection is performed.

[0016] Step 2: Define different oil pump fault levels Different fault levels are defined according to different oil pump fault types. The oil pump fault level is defined according to the severity of the oil pump fault and the impact on the motor. Faults that do not affect the motor performance are defined as level 1 faults, faults that affect the motor cooling performance are defined as level 2 faults, and faults that cause the oil pump to stop rotating are defined as level 3 faults. The oil pump fault includes the original fault reported by the original fault signal of the electronic oil pump and the oil pump speed response fault reported after the processing in step 1; The level 1 faults include: oil pump self-test fault, oil pump over-temperature derating warning; the level 2 faults include: oil pump overload warning, oil pump speed response fault, oil pump over-pressure fault, oil pump under-pressure fault; the level 3 faults include: oil pump over-temperature shutdown fault, oil pump current fault, oil pump communication fault, oil pump jam fault.

[0017] Step 3: Calculate the preconditions for different oil pump failures The prerequisites for the oil pump overload warning, oil pump jam fault, and oil pump speed response fault are that the oil pump temperature is greater than the temperature threshold or the oil pump speed is greater than the speed threshold; the prerequisites for other oil pump faults are that the vehicle power-on signal flag is satisfied; for example, the temperature threshold is set to -10°C in this embodiment, and the speed threshold is 600 revolutions per minute.

[0018] Step 4: Determine whether the current oil pump fault meets the precondition of the oil pump fault calculated in step 3; if so, proceed to step 5; if not, return to step 3; Step 5: define the fault confirmation time threshold and the fault triggering number threshold; for example, in this embodiment, the fault confirmation time threshold is set to 1 minute, and the fault triggering number threshold is set to 3 times.

[0019] Step 6: Determine whether a fault occurs based on whether a fault confirmation time threshold or a fault triggering number threshold is met.

[0020] There are two situations to judge whether a fault has occurred. If one of the following situations is met, the fault is confirmed to have occurred: The duration of the current oil pump fault reaches the fault confirmation time threshold; or the number of fault triggering times in a driving cycle reaches the fault triggering times threshold; If the fault is confirmed to have occurred, proceed to step 7; if the fault is not confirmed to have occurred, return to step 5; In this embodiment, the fault number threshold is set to 3 times.

[0021] The calculation method of the fault triggering times is: if a fault occurs once within a certain period of time, the fault number is increased by one; if no fault occurs within a certain period of time, the fault number is reduced by one. For example, the certain period of time is set to 30ms in this embodiment.

[0022] Step 6 is used to prevent false triggering of faults due to signal interference and other reasons.

[0023] Step 7: Calculate the motor torque limit value for the current oil pump failure The motor torque limit value of the current oil pump fault is calculated according to the different oil pump fault levels defined in step 2. When the fault is level 1, no motor torque limit is performed; when the fault is level 2, a certain motor torque limit is performed, and the certain motor torque limit is specifically limited to half of the rated torque of the motor; when the fault is level 3, the motor torque is limited to 0; Step 8: Calculate the recovery conditions of the current oil pump failure Calculate the recovery condition of the current oil pump fault based on the different oil pump fault levels defined in step 2: The recovery conditions for level 1 and level 2 faults are as follows: The oil pump fault signal stops; Or the number of fault triggering times of the current oil pump fault in one driving cycle is less than a certain fault number threshold, such as the fault number threshold is set to 3 times in this embodiment; The recovery condition for the level 3 fault is to re-energize the vehicle; The calculation method of the fault triggering times is: if a fault occurs within 30ms, the fault number is increased by one; if no fault occurs within 30ms, the fault number is decreased by one; Step 9: Determine whether the current oil pump fault meets the recovery condition calculated in step 8; if so, proceed to step 11; if not, proceed to step 10; Step 10: Limit the motor torque according to the motor torque limit value of the current oil pump fault calculated in step 7, and return to step 9; the level 1 fault and the level 2 fault are based on the torque limit value obtained in step 7, and the maximum operating power of the motor torque is limited by limiting the output performance of the motor. The level 3 fault needs to determine whether the current motor speed is greater than the short-circuit threshold. If it is greater than the short-circuit threshold, the electronic oil pump enters active short-circuit protection. If it is less than the short-circuit threshold, the electronic oil pump enters an open-circuit working state. For example, the short-circuit threshold is set to 4000 revolutions per minute in this embodiment.

[0024] Step 11: Restore the motor torque; release the limit on the motor torque.

[0025] By continuously receiving signals from the electronic oil pump and analyzing the signals, false triggering of faults due to signal interference and other reasons can be prevented, and targeted measures can be taken in a timely manner for different faults. This process can be repeated to adjust the torque of the motor at any time and protect the motor in real time. Example 1

[0026] Step 1: Receive the electronic oil pump operation signal, calculate the speed difference between the oil pump controller request speed and the actual oil pump speed, and if the speed difference is greater than 1000 rpm and lasts for 1 minute, report the oil pump speed response fault signal (hereinafter referred to as "the above fault"); Step 2: Determine that the above fault level is a level 1 fault; Step 3: The precondition for calculating the above fault is that the oil pump temperature is greater than -10°C or the oil pump speed is greater than 600 rpm; Step 4: Determine whether the above fault meets the preconditions. If yes, proceed to the next step. If not, return to the previous step. Step 5: Define the fault confirmation time threshold as 1 minute and the fault triggering number threshold as 3 times; Step 6: Determine whether the above fault meets one of the following conditions, and then confirm that the fault occurs: The duration of the above fault reaches the fault confirmation time threshold; Or the above fault is triggered 3 times in one driving cycle; If the fault is confirmed to have occurred, proceed to step 7; if the fault is not confirmed to have occurred, return to step 5; The calculation method of the fault triggering times is: if a fault occurs within 30ms, the fault number is increased by one; if no fault occurs within 30ms, the fault number is decreased by one; Step 7: According to the fault level of the above fault defined in step 2 as level 1 fault, the oil pump speed response fault torque limit value is calculated, and the motor torque is not limited; Step 8: The fault level of the above fault is level 1 fault, and the recovery conditions are the following two situations: The above fault signal stops; Or the above fault is triggered less than 3 times in one driving cycle; Step 9: Determine whether the current fault meets the recovery condition calculated in step 8; if so, proceed to step 11; if not, proceed to step 10; Step 10: The motor torque limit of the above fault calculated in step 7 is that no motor torque limitation is performed, therefore, the output performance of the motor is not limited, and the maximum operating power of the motor torque is not limited.

[0027] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modification made to the present invention by those skilled in the art without departing from the spirit of the present invention shall fall within the protection scope of the present invention.

Claims

1. A method for handling a fault of an electronic oil pump of a new energy vehicle, characterized in that: The steps include: Step 1: Receive and process the electronic oil pump signal The received electronic oil pump signal includes an original fault signal of the electronic oil pump and an operation signal of the electronic oil pump; The processed electronic oil pump signal is a signal indicating an oil pump speed response fault when the difference between the speed requested by the oil pump controller and the actual speed of the oil pump is greater than a speed difference threshold and the duration reaches a certain time threshold; Step 2: Define different oil pump failure levels Different fault levels are defined according to different oil pump fault types. Faults that do not affect motor performance are defined as level 1 faults, faults that affect motor cooling performance are defined as level 2 faults, and faults that cause the oil pump to stop rotating are defined as level 3 faults. The oil pump fault includes the original fault reported by the original fault signal of the electronic oil pump and the oil pump speed response fault reported after the processing in step 1; Step 3: Calculate the preconditions for different oil pump failures The preconditions for the oil pump overload warning, oil pump stall fault, and oil pump speed response fault are that the oil pump temperature is greater than a temperature threshold or the oil pump speed is greater than a speed threshold; The preconditions for other oil pump failures are that the vehicle power-on signal flag is satisfied; Step 4: Determine whether the current oil pump fault meets the precondition of the oil pump fault calculated in step 3; if so, proceed to step 5; if not, return to step 3; Step 5: Define the fault confirmation time threshold and fault triggering number threshold; Step 6: Determine whether a fault occurs based on whether the fault confirmation time threshold or the fault triggering number threshold is met; There are two situations to judge whether a fault has occurred. If one of the following situations is met, the fault is confirmed to have occurred: The duration of the current oil pump fault reaches the fault confirmation time threshold; or the number of fault triggering times in a driving cycle reaches the fault triggering times threshold; If the fault is confirmed to have occurred, proceed to step 7; if the fault is not confirmed to have occurred, return to step 5; Step 7: Calculate the motor torque limit value for the current oil pump failure The motor torque limit value of the current oil pump fault is calculated according to the different oil pump fault levels defined in step 2. When the fault is level 1, no motor torque limit is performed; when the fault is level 2, a certain motor torque limit is performed; when the fault is level 3, the motor torque is limited to 0; Step 8: Calculate the recovery conditions of the current oil pump failure Calculate the recovery condition of the current oil pump fault based on the different oil pump fault levels defined in step 2: The recovery conditions for level 1 and level 2 faults are as follows: The oil pump fault signal stops; Or the number of fault triggering times of the current oil pump fault in one driving cycle is less than a certain fault number threshold; The recovery condition for the level 3 fault is to re-energize the vehicle; Step 9: Determine whether the current oil pump fault meets the recovery condition calculated in step 8; if so, proceed to step 11; if not, proceed to step 10; Step 10: limit the motor torque according to the motor torque limit value of the current oil pump fault calculated in step 7, and return to step 9; Step 11: Restore the motor torque; release the limit on the motor torque.

2. The method for handling a fault of an electronic oil pump of a new energy vehicle according to claim 1, characterized in that: Step 1, the original fault signal of the electronic oil pump includes: oil pump overvoltage fault, oil pump undervoltage fault, oil pump overtemperature shutdown fault, oil pump current fault, oil pump self-test fault, oil pump overtemperature derating warning, oil pump communication fault, oil pump jam fault, oil pump overload warning; the electronic oil pump operation signal includes: oil pump actual speed, oil pump requested speed, motor oil pump temperature, etc.

3. The method for handling a fault of an electronic oil pump of a new energy vehicle according to claim 1, characterized in that: Step 1: when the oil pump fails to start cold, no oil pump overload warning, oil pump jam fault, or oil pump response fault detection is performed.

4. The method for handling a fault of an electronic oil pump of a new energy vehicle according to claim 1, characterized in that: The level 1 faults described in step 2 include: oil pump self-test fault, oil pump over-temperature derating warning; The second level faults include: oil pump overload warning, oil pump speed response fault, oil pump overpressure fault, and oil pump underpressure fault; The three levels of faults include: oil pump over-temperature shutdown fault, oil pump current fault, oil pump communication fault, and oil pump jam fault.

5. The method for handling a fault of an electronic oil pump of a new energy vehicle according to claim 1, characterized in that: In step 6 and step 8, the calculation method of the fault triggering times is: if a fault occurs once within a certain period of time, the fault number is increased by one; if no fault occurs within a certain period of time, the fault number is decreased by one.

6. The method for handling a fault of an electronic oil pump of a new energy vehicle according to claim 1, characterized in that: The step 7 is to perform a certain motor torque limitation, specifically limiting the motor torque limit value to half of the motor rated torque.

7. The method for handling a fault of an electronic oil pump of a new energy vehicle according to claim 1, characterized in that: In step 10, the level 1 fault and the level 2 fault are based on the torque limit value obtained in step 7, and the maximum operating power of the motor torque is limited by limiting the output performance of the motor. The level 3 fault needs to determine whether the current motor speed is greater than the short-circuit threshold. If it is greater than the short-circuit threshold, the electronic oil pump enters active short-circuit protection. If it is less than the short-circuit threshold, the electronic oil pump enters an open-circuit working state.

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