A control method, system and vehicle for a speed reducer oil pump

Abstract

The present invention relates to a control method, system and vehicle for a reducer oil pump. The control method comprises: when the motor is in a preset working mode, determining whether the current wheel speed difference is greater than a preset difference, if not, executing: calculating and determining the offset oil pump speed based on the current motor speed and speed offset value of the reducer, and calculating the oil pump speed of the next cycle based on the rising slope of the current speed of the reducer oil pump; comparing the offset oil pump speed with the oil pump speed of the next cycle, judging whether the offset oil pump speed is less than the oil pump speed of the next cycle, if so, reducing the speed, if not, increasing the speed; and sending a request for the oil pump speed. The present invention also provides a control system and vehicle for a reducer oil pump. The present invention accurately controls the oil injection amount of the reducer oil pump, solving the problem that it is difficult to effectively lubricate the reducer when the vehicle is in an off-road scene with a large wheel speed difference.

Description

Technical Field

[0001] The present invention relates to the technical field of speed reducers, and in particular to a control method, system and vehicle for a speed reducer oil pump. Background Art

[0002] In today's society, with the increasing abundance of material life and the continuous improvement of people's spiritual pursuits, outdoor adventures and activities close to nature have become an indispensable part of many people's lives. However, while enjoying the tranquility and harmony of nature, it is inevitable to encounter muddy, rugged, and even extremely harsh driving conditions, all of which pose severe challenges to the performance and durability of vehicles.

[0003] Especially when encountering muddy, bumpy, or uneven road conditions that leave some wheels hanging in the air, conventional vehicles may be unable to free themselves due to insufficient driving force or the differential's inability to deliver torque, making them unable to free themselves. Four-wheel drive off-road vehicles are typically equipped with differential locks, which lock the drive wheel differentials, allowing the drive wheels to deliver torque normally and help the vehicle escape. However, when the differential is locked, the vehicle needs to deliver high torque at low speed to escape, placing a significant load on the reducer. The existing splash lubrication alone is no longer effective in protecting the reducer. The reducer is a critical component, and the constant impact of high loads and frequent locking and unlocking can easily lead to wear, overheating, and even damage, which can affect the vehicle's overall performance and service life.

[0004] Therefore, there is an urgent need to develop an active lubrication reducer control strategy that can accurately control the oil pump to spray lubricating oil in a wild off-road environment to meet users' love for off-road driving while ensuring that the reducer is properly protected.

[0005] The prior art generally discloses an automotive oil pump control system based on CAN and LIN communications. This control system is mainly used for controlling the brushless motor-driven oil pump of an automotive oil pump. This low-power technology can reduce the standby power consumption of the drive control board when the oil pump is in standby mode, thereby extending the standby life of the vehicle battery and preventing the vehicle from being unable to start due to low battery power caused by useless standby power consumption. However, the impact of off-road scenarios on high loads of electric drives is not mentioned. Summary of the Invention

[0006] In view of this, the purpose of the present invention is to provide a control method, system, vehicle and electronic equipment for a reducer oil pump to accurately control the oil injection amount of the reducer oil pump, and also to solve the problem of difficulty in achieving effective lubrication of the reducer when the vehicle has a large wheel speed difference in off-road scenarios in the wild.

[0007] In order to achieve the above object, the technical solution adopted by the present invention is as follows:

[0008] A method for controlling a reducer oil pump comprises the following steps:

[0009] S1. When the motor is in a preset working mode, determine whether the current wheel speed difference is greater than a preset difference. If not, execute S2.

[0010] S2. Confirm the speed offset coefficient based on the ambient temperature, determine the oil pump speed before the offset based on the current motor speed of the reducer, calculate the oil pump speed after the offset based on the offset coefficient and the oil pump speed before the offset, and calculate the oil pump speed for the next cycle based on the rising slope of the current speed of the reducer oil pump;

[0011] Comparing the offset oil pump speed with the oil pump speed of the next cycle, when the offset oil pump speed is less than the oil pump speed of the next cycle, determining the required oil pump speed to be the current oil pump speed minus the preset oil pump speed to achieve speed reduction; when the offset oil pump speed is greater than or equal to the oil pump speed of the next cycle, determining the required oil pump speed to be the offset oil pump speed to achieve speed increase;

[0012] S3. Transmitting the request for the oil pump speed to the oil pump to implement oil pump injection control to protect the reducer.

[0013] The aforementioned technical approach combines the motor operating mode, wheel speed differential, reducer motor speed, and ambient temperature to determine the required oil pump speed through comprehensive calculation. This speed request is then transmitted to the oil pump, allowing for accurate control of the oil injection volume. This ensures effective lubrication of the reducer, improves the adaptability of the lubrication system, effectively protects the reducer, and enhances vehicle safety and reliability. This allows for timely and precise control of the oil injection volume, particularly in situations with large wheel speed differentials in off-road driving. This resolves the issue of difficulty in achieving effective lubrication of the reducer in situations with large wheel speed differentials in off-road driving.

[0014] Preferably, in S3, the request for the required oil pump speed is transmitted to the oil pump via a communication module, and the communication module includes:

[0015] A LIN internal communication module realizes information exchange between the ECU of the motor controller and the LIN internal communication module through SPI communication;

[0016] The vehicle wiring harness realizes information interaction between the LIN internal communication module and the reducer controller EOP through the vehicle wiring harness, so as to establish external communication with the oil pump through the LIN internal communication module and transmit the request for the oil pump speed to the oil pump.

[0017] By setting up LIN communication, real-time monitoring of the reducer can be achieved, and the oil pump speed can be adjusted promptly and accurately, thereby improving the safety and reliability of vehicle operation.

[0018] Preferably, the rotational speed offset coefficient is obtained by looking up a comparison table of ambient temperature and rotational speed offset coefficient.

[0019] Preferably, the oil pump speed before the offset is obtained by looking up a comparison table between the current motor speed of the reducer and the oil pump speed before the offset.

[0020] Preferably, in S1, the control method further includes:

[0021] Determine whether the reducer has a reducer oil pump fault, where the reducer oil pump fault includes an oil pump fault itself and / or a LIN communication fault.

[0022] Throughout the control method's execution, the system determines in real time whether the reducer's oil pump is faulty. This allows for timely detection and resolution of the problem, avoiding equipment damage and production interruptions. This reduces the risk of sudden failures, helps extend the reducer's service life, improves equipment efficiency, and reduces maintenance costs. By distinguishing between oil pump failures and LIN communication failures, the problem can be more accurately located, improving maintenance efficiency.

[0023] Preferably, in S1, the preset working mode includes any one of a standby mode, a Ud control mode, a torque control mode, a ready-to-sleep mode, and a discharge mode;

[0024] If it is determined that the reducer is faulty or the motor is not in the preset working mode, the required oil pump speed is determined to be 0.

[0025] If a reducer failure is detected or the motor operating mode is outside the preset setting, the system automatically determines and sets the required oil pump speed to zero. This effectively prevents equipment from operating under unsuitable conditions, avoiding potential damage and maintenance costs. By promptly stopping the oil pump, system safety and reliability are ensured, while also reducing production interruptions caused by failures.

[0026] When the motor operating mode is any one of the initialization mode, the pre-charge mode and the fault mode, it indicates that the motor operating mode is not in the preset operating mode.

[0027] Preferably, in said S1, if the current wheel speed difference is greater than a preset difference, it is determined that the required oil pump speed is the maximum oil pump speed.

[0028] When a wheel speed difference greater than a preset value is detected, the system rapidly adjusts the oil pump speed to its maximum setting, ensuring sufficient hydraulic power in emergency situations and rapidly responding to the vehicle's dynamic demands. This timely increase in oil pump speed effectively reduces the risk of wheel slippage or loss of control, enhances vehicle stability in complex road conditions, and improves driving safety. This design reflects a deep understanding of vehicle dynamic performance and optimizes vehicle handling performance and fuel efficiency through intelligent oil pump control strategies. By setting a preset differential, the system proactively intervenes before any problems occur, reducing wear caused by prolonged, inefficient operation of the oil pump and extending its service life. Drivers experience more responsive and reliable handling in unexpected situations, enhancing the driving experience.

[0029] Preferably, in S1, the wheel speed difference represents the difference between the rotation speeds of the left rear wheel and the right rear wheel of the vehicle.

[0030] Preferably, in S2, the rising slope is the rising value of the speed of the reducer oil pump per second.

[0031] Among them, the motor working mode is controlled by the VCU request working mode.

[0032] The current motor speed is calculated based on the sin and cos excitation values ​​collected from the resolver feedback. After the hardware collects the feedback excitation value (black line), the outer envelope of the feedback excitation value is obtained by plotting the points, and the true value of sin_value / cos_value is obtained (red line).

[0033] The sin and cos excitation values ​​of resolver feedback typically refer to the sine (sin) and cosine (cos) function values ​​used to describe the rotation angle in the resolver sensor. These values ​​reflect the phase θ change of the resolver sensor's output signal and are important parameters for evaluating rotation angle and speed. The angle is calculated using the following formula:

[0034] sin_value = Asin(θ)

[0035] cos_value = Acos(θ)

[0036] θ = arctan(sin_value / cos_value)

[0037] Where θ represents the rotation angle. By measuring the sin and cos excitation values, where sin_value represents the outer envelope of the measured sin excitation value and cos_value represents the outer envelope of the measured cos excitation value, the resolver's rotation angle can be determined, enabling precise position and speed control.

[0038] Current motor speed = (△θ / 360) / △t

[0039] Here, △θ represents the angle change within a cycle, and △t represents the duration of a cycle. In this application, the cycle duration is set to 102.4 μs. For example, if the angle change within a cycle is 1°, the current motor speed is 1 / 360 / (102.4 / 1000 / 1000 / 60) = 1627.6 rpm.

[0040] The present invention also provides a control system for a reducer oil pump, comprising a memory and a processor, wherein the memory stores a computer program, and the processor implements the steps of the control method for the reducer oil pump as described in the present invention when executing the computer program.

[0041] The present invention also provides a vehicle, comprising the control system of the reducer oil pump of the present invention.

[0042] Beneficial effects of the present invention:

[0043] The control method for a reducer oil pump of the present invention checks the operating mode of the motor, which helps to promptly discover and address problems and avoid further damage. By determining whether the current wheel speed difference is greater than a preset difference, the oil pump speed can be dynamically adjusted according to actual operating conditions, thereby improving the adaptability and flexibility of the system. By considering the impact of ambient temperature on the oil pump speed, confirming the speed offset coefficient and calculating the oil pump speed after the offset, the method can adapt to different operating environments and ensure stable operation of the reducer. By calculating the oil pump speed for the next cycle based on the rising slope of the current oil pump speed, the method has a certain degree of predictability and can make adjustments in advance to optimize the operating efficiency of the reducer. By comparing the oil pump speed after the offset with the oil pump speed for the next cycle and determining the required oil pump speed accordingly, the method can effectively control the oil pump speed to protect the reducer from damage. By transmitting a request for the required oil pump speed to the oil pump, the oil injection amount can be accurately controlled. The method can respond to system requirements in real time, thereby ensuring effective lubrication of the reducer, improving the adaptability of the lubrication system, ensuring the normal operation of the reducer, and improving the safety and reliability of vehicle operation. In particular, the method can promptly and accurately control the oil injection amount when the vehicle is in an off-road scenario with a large wheel speed difference. The invention solves the problem that it is difficult to effectively lubricate the reducer when the vehicle has a large wheel speed difference in off-road scenes, and has promotion and application value in the field of reducer technology. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] Figure 1 Flowchart of the control method of the reducer oil pump of the present invention;

[0045] Figure 2 This is a schematic diagram of the control method of the reducer oil pump of the present invention. DETAILED DESCRIPTION

[0046] The following describes the embodiments of the present invention with reference to the accompanying drawings and preferred embodiments. Those skilled in the art will readily appreciate the other advantages and benefits of the present invention from the disclosure herein. The present invention may also be implemented or applied through various other specific embodiments, and the various details in this specification may be modified or altered based on different viewpoints and applications without departing from the spirit of the present invention. It should be understood that the preferred embodiments are intended only to illustrate the present invention and are not intended to limit the scope of protection of the present invention.

[0047] It should be noted that the illustrations provided in the following embodiments are merely schematic illustrations of the basic concept of the present invention. Therefore, the illustrations only show components related to the present invention and are not drawn according to the number, shape, and size of components in actual implementation. In actual implementation, the type, quantity, and proportion of each component may be changed arbitrarily, and the component layout may also be more complex.

[0048] In the following description, numerous details are discussed to provide a more thorough explanation of the embodiments of the present application. However, it is obvious to those skilled in the art that the embodiments of the present application can be implemented without these specific details.

[0049] The present invention provides a control method, system, and vehicle for a speed reducer oil pump, enabling accurate control of the oil injection rate from the speed reducer pump. This method also addresses the difficulty in achieving effective lubrication of the speed reducer during off-road driving with large wheel speed differences.

[0050] Among them, such as Figure 1 As shown, a control method for a reducer oil pump includes the following steps:

[0051] S1. When the motor is in a preset working mode, determine whether the current wheel speed difference is greater than a preset difference. If not, execute S2.

[0052] S2. Confirm the speed offset coefficient based on the ambient temperature, determine the oil pump speed before the offset based on the current motor speed of the reducer, and calculate the oil pump speed after the offset based on the offset coefficient and the oil pump speed before the offset; at the same time, calculate the oil pump speed for the next cycle based on the rising slope of the current speed of the reducer oil pump;

[0053] Comparing the offset oil pump speed with the oil pump speed of the next cycle, when the offset oil pump speed is less than the oil pump speed of the next cycle, determining the required oil pump speed to be the current oil pump speed minus the preset oil pump speed to achieve speed reduction; when the offset oil pump speed is greater than or equal to the oil pump speed of the next cycle, determining the required oil pump speed to be the offset oil pump speed to achieve speed increase;

[0054] S3: Transmit the request for the oil pump speed to the oil pump to implement the oil pump injection control to protect the reducer.

[0055] The required oil pump speed is determined by combining the motor operating mode, wheel speed differential, reducer motor speed, and ambient temperature. This speed request is then transmitted to the oil pump, accurately controlling the oil injection volume. This ensures effective lubrication of the reducer, improves the adaptability of the lubrication system, effectively protects the reducer, and enhances vehicle safety and reliability. This is particularly true in off-road driving scenarios with large wheel speed differentials, enabling timely and precise control of oil injection volume. This solves the problem of difficulty in achieving effective lubrication of the reducer in off-road driving scenarios with large wheel speed differentials.

[0056] Exemplarily, the preset oil pump speed is 10 rpm.

[0057] Among them, in S2, the oil pump speed rising slope is a fixed value of 1000 rpm / s, and the cycle time is 10ms, that is, the speed rises by 10 rpm in one cycle, and the oil pump speed in the next cycle = current speed + 10 rpm.

[0058] In some embodiments, in S3, the request for the oil pump speed is transmitted to the oil pump via a communication module, and the communication module includes:

[0059] LIN internal communication module, which realizes information exchange between the motor controller ECU and the LIN internal communication module through SPI communication;

[0060] The vehicle wiring harness realizes information interaction between the LIN internal communication module and the reducer controller EOP through the vehicle wiring harness, so as to establish external communication with the oil pump through the LIN internal communication module and transmit the request for the oil pump speed to the oil pump.

[0061] In some embodiments, the communication module further includes: a vehicle twisted pair cable, which establishes CAN communication with other external controllers through the vehicle twisted pair cable.

[0062] Among them, such as Figure 2 As shown in the figure, the principle of the control method of the reducer oil pump is as follows: the motor controller is awakened by an external hard line to maintain the working state. When there is no hard line awakening, the motor controller maintains a low power consumption state to avoid battery power feeding; after the motor controller wakes up, CAN communication is established with other external controllers through the vehicle twisted pair cable; SPI communication is established with the LIN chip through the LIN module built into the MCU of the motor controller; and communication is established with the oil pump controller EOP through the vehicle wiring harness connection; thereby achieving the connection between the motor controller and the oil pump controller, thereby controlling the operation of the oil pump.

[0063] In some embodiments, the rotational speed offset coefficient frac1 is obtained by looking up a comparison table of ambient temperature and rotational speed offset coefficients. The comparison table of ambient temperature T and rotational speed offset coefficient frac1 is obtained through experimental calibration.

[0064] Among them, the comparison table of ambient temperature T and speed offset coefficient frac1 is:

[0065] T_block

[11] [1]={(-35.0,1.10),(-30.0,1.09),(-25.0,1.08),(-20.0,1.07),(-15.0, 1.06),(-10.0,1.05),(-5.0,1.04),(0.0,1.03),(5.0,1.02),(15.0,1.01),(25.0,1.0)} .

[0066] In the comparison table, the brackets () on the right side of the equation, such as (-35.0, 1.10), correspond to (ambient temperature, speed offset coefficient). Adjacent brackets, such as (-35.0, 1.10) and (-30.0, 1.09), indicate that the ambient temperature is between -35°C and -30°C, and the speed offset coefficient is 1.10 or 1.09. In actual application, the collected ambient temperature is compared with the ambient temperature in the comparison table. If the temperature is between the two, the larger value of the speed offset coefficient frac1 is used as the speed offset coefficient frac1. The maximum value of the speed offset coefficient frac1 is 1.1, and the minimum value of the speed offset coefficient frac1 is 1.0.

[0067] In some embodiments, the oil pump speed spd2 before the offset is obtained by looking up a comparison table between the current motor speed of the reducer and the oil pump speed spd2 before the offset. The oil pump speed spd2 before the offset is obtained by looking up a comparison table between the current motor speed of the reducer and the oil pump speed spd2 before the offset through experimental calibration.

[0068] Among them, the comparison table of the current motor speed of the reducer and the oil pump speed spd2 before offset is:

[0069] Spd_block

[18] [1]={(1.0,0.0),(50.0,0.0),(100.0,500.0),(201.0,1000.0 ),(501.0,1400.0),(1001.0,1800.0),(1501.0,2200.0),(2001.0,2500.0),( 2495.0,2800.0),(2496.0,0.0),(3501.0,0.0),(4001.0,0.0),(4501.0,0.0) ,(5001.0,0.0),(5501.0,0.0),(6001.0,0.0),(6501.0,0.0),(7001.0,0.0)}. In the comparison table, the brackets () on the right side of the equation, such as (1.0, 0.0), correspond to (current motor speed, oil pump speed before offset). Adjacent brackets, such as (1.0, 0.0) and (50.0, 0.0), indicate that the ambient temperature is between 1.0 and 50.0, and the speed offset coefficient is 0.0. Using the comparison table between the current reducer motor speed and the oil pump speed spd2 before offset, the oil pump speed spd2 before offset is obtained based on the current reducer motor speed. After the motor speed exceeds 2496 rpm, the oil pump speed request becomes 0, indicating that the vehicle is traveling at high speed and no oil pump lubrication is required.

[0070] In some embodiments, the post-shift oil pump speed is the product of the offset coefficient and the pre-shift oil pump speed. Specifically, the calculation formula is: SpdReq = spd2 * frac1, where SpdReq represents the post-shift oil pump speed, spd2 represents the pre-shift oil pump speed, and frac1 represents the offset coefficient. If the calculated post-shift oil pump speed SpdReq is greater than 2800, the post-shift oil pump speed SpdReq is limited to 2800.

[0071] In some embodiments, the control method further includes:

[0072] Determine in real time whether there is a reducer oil pump fault in the reducer, so as to discover and handle the problem in time, avoid equipment damage and production interruption, and reduce the risk of sudden failure. Reducer oil pump failure includes oil pump failure itself and / or LIN communication failure, so as to locate the problem more accurately and improve maintenance efficiency.

[0073] In some embodiments, in S1 , the preset working mode includes any one of a standby mode, a Ud control mode, a torque control mode, a ready-to-sleep mode, and a discharge mode.

[0074] In some embodiments, to prevent equipment from operating under inappropriate conditions, thereby avoiding potential damage and maintenance costs, in S1, if it is determined that the reducer is faulty or the motor is not operating in the preset mode, the required oil pump speed is determined to be 0. This timely stopping of the oil pump ensures system safety and reliability while reducing production interruptions caused by faults.

[0075] When the motor operating mode is any one of the initialization mode, the pre-charge mode and the fault mode, it indicates that the motor operating mode is not in the preset operating mode.

[0076] In some embodiments, to ensure sufficient hydraulic power in emergency situations and thus quickly respond to the dynamic needs of the vehicle, in S1 , if the current wheel speed difference is greater than a preset difference, the required oil pump speed is determined to be the maximum oil pump speed.

[0077] In some embodiments, in S1 , the wheel speed difference represents the difference between the rotation speeds of the left rear wheel and the right rear wheel of the vehicle.

[0078] Exemplarily, the preset difference in wheel speed is 20 km / h.

[0079] In some embodiments, in S2 , the rising slope is the rising value of the speed of the retarder oil pump per second.

[0080] Among them, the motor working mode is controlled by the VCU request working mode.

[0081] The current motor speed is calculated based on the sin and cos excitation values ​​collected from the resolver feedback. After the hardware collects the feedback excitation value (black line), the outer envelope of the feedback excitation value is obtained by plotting the points, and the true value of sin_value / cos_value is obtained (red line).

[0082] The sin and cos excitation values ​​of resolver feedback typically refer to the sine (sin) and cosine (cos) function values ​​used to describe the rotation angle in the resolver sensor. These values ​​reflect the phase θ change of the resolver sensor's output signal and are important parameters for evaluating rotation angle and speed. The angle is calculated using the following formula:

[0083] sin_value = Asin(θ)

[0084] cos_value = Acos(θ)

[0085] θ = arctan(sin_value / cos_value)

[0086] Where θ represents the rotation angle. By measuring the sin and cos excitation values, where sin_value represents the outer envelope of the measured sin excitation value and cos_value represents the outer envelope of the measured cos excitation value, the resolver's rotation angle can be determined, enabling precise position and speed control.

[0087] Current motor speed = (△θ / 360) / △t

[0088] Here, △θ represents the angle change within a cycle, and △t represents the duration of a cycle. In this application, the cycle duration is set to 102.4 μs. For example, if the angle change within a cycle is 1°, the current motor speed is 1 / 360 / (102.4 / 1000 / 1000 / 60) = 1627.6 rpm.

[0089] The oil pump is mechanically attached to the reducer. It draws oil from the base of the reducer, which then enters the pump. The oil is then pressurized by the pump and sprayed through an oil pipe into the differential lock (attached to the reducer), protecting the reducer. The oil pump itself is electrically powered and does not share a power source with the reducer, enabling precise control of the injection volume.

[0090] In some embodiments, a control system for a reducer oil pump is also provided, comprising a memory and a processor, wherein the memory stores a computer program, and when the processor executes the computer program, the steps of the control method for the reducer oil pump in any of the above embodiments are implemented.

[0091] In some embodiments, a vehicle is further provided, comprising the control system of the retarder oil pump in any of the above embodiments.

[0092] In summary, the reducer oil pump control method of the present invention first checks whether the motor operating mode is within the preset operating mode, allowing for timely identification and resolution of issues and preventing further damage. Next, by determining whether the current wheel speed difference exceeds a preset threshold, the oil pump speed is dynamically adjusted based on actual operating conditions, thereby enhancing the system's adaptability and flexibility. Furthermore, this method considers the impact of ambient temperature on the oil pump speed and calculates the adjusted oil pump speed by determining a speed offset coefficient, ensuring stable operation of the reducer under varying operating conditions. By calculating the current oil pump speed's rising slope and predicting the oil pump speed for the next cycle, this method is proactive, enabling proactive adjustments and optimizing reducer efficiency. By comparing the adjusted oil pump speed with the predicted speed for the next cycle, the desired oil pump speed is determined, effectively controlling the oil pump speed and protecting the reducer from damage. Finally, the desired oil pump speed command is transmitted to the oil pump, precisely controlling the oil injection rate, ensuring real-time response to system requirements and ensuring effective lubrication of the reducer. This method improves the adaptability of the lubrication system, ensures proper operation of the reducer, and enhances the safety and reliability of vehicle operation. Especially when the vehicle is performing off-road driving in the wild, facing a large wheel speed difference, this method can timely and accurately control the oil injection amount, effectively solving the technical problem of difficult to achieve effective lubrication of the reducer in off-road scenarios, and has the potential for promotion and application in the field of reducer technology.

[0093] The above embodiments are merely illustrative of the principles and effects of the present invention and are not intended to limit this application. Anyone skilled in the art may modify or alter the above embodiments without departing from the spirit and scope of this application. Therefore, any equivalent modifications or alterations made by a person of ordinary skill in the art without departing from the spirit and technical concepts disclosed in this application shall be encompassed by the claims of this application.

Claims

1. A control method for a reducer oil pump, characterized in that: The following steps are involved: S1. When the motor is in a preset working mode, determine whether the current wheel speed difference is greater than a preset difference. If not, execute S2. S2. Confirm the speed offset coefficient based on the ambient temperature, determine the oil pump speed before the offset based on the current motor speed of the reducer, calculate the oil pump speed after the offset based on the speed offset coefficient and the oil pump speed before the offset, and calculate the oil pump speed for the next cycle based on the rising slope of the current speed of the reducer oil pump; Comparing the offset oil pump speed with the oil pump speed of the next cycle; when the offset oil pump speed is less than the oil pump speed of the next cycle, determining the required oil pump speed to be the current oil pump speed minus the preset oil pump speed; and when the offset oil pump speed is greater than or equal to the oil pump speed of the next cycle, determining the required oil pump speed to be the offset oil pump speed; S3. Transmitting the request for the oil pump speed to the oil pump to implement oil pump injection control to protect the reducer.

2. The control method of the reducer oil pump according to claim 1, characterized in that: In S3, the request for the oil pump speed is transmitted to the oil pump via a communication module, wherein the communication module includes: A LIN internal communication module realizes information exchange between the ECU of the motor controller and the LIN internal communication module through SPI communication; The vehicle wiring harness realizes information interaction between the LIN internal communication module and the reducer controller EOP through the vehicle wiring harness, so as to establish external communication with the oil pump through the LIN internal communication module and transmit the request for the oil pump speed to the oil pump.

3. The control method of the reducer oil pump according to claim 1, characterized in that: The speed offset coefficient is obtained by looking up the comparison table of ambient temperature and speed offset coefficient; And / or, the oil pump speed before the offset is obtained by looking up a comparison table between the current motor speed of the reducer and the oil pump speed before the offset.

4. The control method of the reducer oil pump according to claim 1, characterized in that: The oil pump speed after the offset is the product of the offset coefficient and the oil pump speed before the offset.

5. The control method of the reducer oil pump according to claim 1, characterized in that: The control method further includes: Determine whether the reducer has a reducer oil pump fault, where the reducer oil pump fault includes an oil pump fault itself and / or a LIN communication fault.

6. The control method of the reducer oil pump according to claim 5, characterized in that: In S1, the preset working mode includes any one of a standby mode, a Ud control mode, a torque control mode, a sleep preparation mode, and a discharge mode; If it is determined that the reducer has a fault or the motor operating mode is not in the preset operating mode, the required oil pump speed is determined to be 0.

7. The control method of the reducer oil pump according to claim 1, characterized in that: In S1 , if the current wheel speed difference is greater than a preset difference, the required oil pump speed is determined to be the maximum oil pump speed.

8. The control method of the reducer oil pump according to claim 1, characterized in that: In S1, the wheel speed difference represents the difference between the rotation speeds of the left rear wheel and the right rear wheel of the vehicle; And / or, in S2, the rising slope is the rising value of the speed of the reducer oil pump per second.

9. A control system for a reducer oil pump, comprising a memory and a processor, wherein the memory stores a computer program, characterized in that: When the processor executes the computer program, the steps of the method for controlling the reducer oil pump according to any one of claims 1 to 8 are implemented.

10. A vehicle, characterized in that: The vehicle includes the control system for the retarder oil pump according to claim 9.

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