Electric drive system, control method with electric drive system and vehicle with electric drive system

Abstract

The invention provides an electric drive system, a control method with the electric drive system and a vehicle with the electric drive system. The electric drive system comprises an oil pool, lubricating oil is contained in the oil pool, and a temperature sensor is arranged on the side wall of the oil pool; the electric driving device comprises a controller and an oil quantity adjusting assembly, and the controller is electrically connected with the temperature sensor and the oil quantity adjusting assembly; wherein one end of the oil quantity adjusting assembly communicates with the oil pool, lubricating oil can flow into the oil quantity adjusting assembly from the oil pool, and the oil quantity adjusting assembly is used for adjusting the oil quantity in the oil pool. The problems that in the prior art, the lubricating oil amount of an electric drive system is fixed under different working conditions, oil stirring losses are large under the high-speed and high-temperature working conditions, and efficiency is reduced are solved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of automobile power systems, in particular to an electric drive system, a control method thereof and a vehicle. BACKGROUND

[0002] In the prior art, the lubricating oil amount of the electric drive system is usually designed as a fixed value, which is mainly to meet the lubrication requirements of the vehicle under different vehicle speeds and oil temperature conditions. However, this fixed oil amount design has obvious shortcomings. When the vehicle is running at low speed, the rotating parts of the electric drive system rotate at low speed, and the oil pool working oil temperature is at a low level. At this time, the amount of lubricating oil in the oil pool may exceed the actual lubricating amount required by the system. On the contrary, in high-speed driving, the rotating parts rotate at a high speed, although the oil temperature is increased at this time, the lubrication requirement is increased, but due to the fixed oil amount, the amount of lubricating oil in the oil pool will exceed the oil amount required by the system when running at high speed. In this case, too much lubricating oil participates in oil stirring, which causes the oil stirring loss to increase, triggering a series of chain reactions: the oil temperature is increased, the oil pressure is increased, and then the efficiency and performance of the electric drive system are affected.

[0003] At present, there is no effective solution to the above problems. SUMMARY

[0004] The main purpose of the present application is to provide an electric drive system, a control method thereof and a vehicle, so as to solve the problem that the lubricating oil amount of the electric drive system is fixed in the prior art under different working conditions, resulting in large oil stirring loss and low efficiency under high-speed high-temperature working conditions.

[0005] In order to achieve the above purpose, according to one aspect of the present application, an electric drive system is provided, comprising: an oil pool, the oil pool internally containing lubricating oil, and a temperature sensor being arranged on the side wall of the oil pool; an electric drive device, the electric drive device comprising a controller and an oil amount adjusting assembly, the controller being electrically connected with the temperature sensor and the oil amount adjusting assembly; wherein one end of the oil amount adjusting assembly is arranged in communication with the oil pool, the lubricating oil can flow from the oil pool into the oil amount adjusting assembly, and the oil amount adjusting assembly is used for adjusting the oil amount in the oil pool.

[0006] Further, the oil amount adjusting assembly comprises: an oil amount adjuster cylinder body, the oil amount adjuster cylinder body internally having a containing cavity, and the bottom of the oil amount adjuster cylinder body being provided with an oil port, the oil amount adjuster cylinder body being arranged in communication with the oil pool through the oil port; a motor, the motor being electrically connected with the controller; a piston, the two ends of the piston being abutted with the side wall of the oil amount adjuster cylinder body, and the motor controlling the piston to reciprocate along the length direction of the oil amount adjuster cylinder body, so as to make the lubricating oil flow between the containing cavity and the oil pool.

[0007] According to another aspect of the present application, a control method of an electric drive system is provided for controlling the electric drive system to adjust the amount of oil in an oil pool, the control method comprising: obtaining an oil temperature signal of the oil pool, wherein the oil temperature signal is collected by a temperature sensor; obtaining a driving speed of the vehicle; determining whether the oil temperature signal satisfies a preset condition based on the driving speed, and generating a determination result if the oil temperature signal is determined to satisfy the preset condition; and generating a control strategy set based on the determination result.

[0008] Further, generating the control strategy set based on the determination result comprises: generating a first control strategy if the driving speed is determined to be high and the oil temperature signal exceeds a preset first temperature threshold; and generating a second control strategy if the driving speed is determined to be low and the oil temperature signal is lower than a preset second temperature threshold.

[0009] Further, generating the first control strategy if the driving speed is determined to be high and the oil temperature signal exceeds the preset first temperature threshold comprises: controlling the electric drive device to execute a first working mode for reducing the amount of oil in the oil pool to a first preset oil amount if the oil temperature signal is determined to exceed the preset first temperature threshold; obtaining the oil temperature signal of the oil pool or an oil suction amount in the electric drive device; and controlling the electric drive device to stop running if the oil temperature signal is determined to be lower than the first temperature threshold or the oil suction amount is greater than a third preset oil amount.

[0010] Further, generating the second control strategy if the driving speed is determined to be low and the oil temperature signal is lower than the preset second temperature threshold comprises: controlling the electric drive device to execute a second working mode for increasing the amount of oil in the oil pool to a second preset oil amount if the oil temperature signal is determined to be lower than the preset second temperature threshold; obtaining the oil temperature signal of the oil pool or an oil discharge amount in the electric drive device; and controlling the electric drive device to stop running if the oil temperature signal is determined to exceed the second temperature threshold or the oil discharge amount is greater than the third preset oil amount.

[0011] Further, controlling the electric drive device to execute the first working mode if the oil temperature signal is determined to exceed the preset first temperature threshold comprises: controlling the motor to rotate in a forward direction to drive the piston to move away from the oil pool and cause the lubricating oil in the oil pool to flow into the oil amount regulator cylinder if the oil temperature signal is determined to exceed the preset first temperature threshold.

[0012] Further, controlling the electric drive device to execute the second working mode if the oil temperature signal is determined to be lower than the preset second temperature threshold comprises:

[0013] Further, controlling the electric drive device to execute the second working mode if the oil temperature signal is determined to be lower than the preset second temperature threshold comprises: controlling the motor to rotate in a reverse direction to drive the piston to move towards the oil pool and cause the lubricating oil in the oil amount regulator cylinder to be discharged into the oil pool.

[0014] Further, the control method further comprises: in a case where it is determined that the oil temperature signal is between the first temperature threshold and the second temperature threshold, generating a third control strategy, the third control strategy being used to control the oil amount in the oil pool to remain unchanged.

[0015] According to another aspect of the present application, a vehicle is provided, comprising the control method of the electric drive system.

[0016] By applying the technical solution of the present application, the present application dynamically adjusts the amount of lubricating oil in the oil pool through the oil amount adjusting assembly, effectively reduces the oil stirring loss of the electric drive system under high-speed high-temperature working conditions, and significantly improves the overall efficiency of the electric drive system. Not only the efficiency of the electric drive system is improved, but also the frequent start of the system overheating protection mechanism caused by excessively high oil temperature is effectively avoided, the working time of high-torque output is prolonged, and the power performance of the vehicle is further enhanced. The present application solves the problem in the prior art that the amount of lubricating oil of the electric drive system is fixed under different working conditions, resulting in large oil stirring loss and low efficiency under high-speed high-temperature working conditions. BRIEF DESCRIPTION OF DRAWINGS

[0017] The drawings accompanying the specification of the present application form a part thereof, serve to provide further understanding of the present application, and together with the description of the exemplary embodiments of the present application and the explanation thereof serve to explain the present application, and do not constitute improper limitations on the present application. In the drawings:

[0018] Figure 1 A structural schematic diagram of an embodiment of the electric drive system according to the present application is shown;

[0019] Figure 2 A flowchart of an embodiment of the control method of the electric drive system according to the present application is shown.

[0020] Among them, the above drawings include the following reference signs:

[0021] 11, electric drive device;

[0022] 111, temperature sensor;

[0023] 112, controller;

[0024] 113, oil amount adjusting assembly;

[0025] 1131, motor;

[0026] 1132, piston;

[0027] 1133, oil amount adjuster barrel;

[0028] 1134, oil port;

[0029] 12, oil pool. DETAILED DESCRIPTION

[0030] It should be noted that the embodiments and features of the embodiments in the present application can be combined if there is no conflict. The present application will be described in detail below with reference to the accompanying drawings and in conjunction with embodiments.

[0031] It should be noted that the terms used herein are only intended to describe specific embodiments and are not intended to limit exemplary embodiments according to the present application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise, and it should be understood that the terms "comprise" and / or "include" when used in this specification, specify the presence of stated features, steps, operations, devices, components and / or combinations thereof.

[0032] It should be noted that the terms "first", "second", and the like in the specification of the present application and the above-described drawings are used to distinguish similar objects, and do not necessarily have to describe a specific order or sequence. It should be understood that the terms used in this way can be interchanged as appropriate, so that the embodiments of the present application described herein can be implemented, for example, in an order other than that illustrated or described herein. In addition, the terms "include" and "have" and any variations thereof are intended to cover non-exclusive inclusion, for example, a process, method, system, product or device that includes a series of steps or units does not have to be limited to only those steps or units clearly listed, but can include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0033] Now, exemplary embodiments according to the present application will be described in more detail with reference to the accompanying drawings. However, these exemplary embodiments can be implemented in various different forms, and should not be interpreted as being limited only to the embodiments set forth herein. It should be understood that these embodiments are provided in order to make the present disclosure complete and complete, and to adequately convey the ideas of these exemplary embodiments to those of ordinary skill in the art. In the drawings, the thickness of layers and regions can be exaggerated for clarity, and the same reference numerals are used to denote the same elements, so that a description thereof will be omitted.

[0034] In conjunction with Figure 1 As shown, according to specific embodiments of the present application, an electric drive system is provided.

[0035] Specifically, the electric drive system comprises: an oil pool 12, the inside of the oil pool 12 containing lubricating oil, and a temperature sensor 111 arranged on the side wall of the oil pool 12; an electric drive device 11, the electric drive device 11 comprising a controller 112 and an oil amount adjusting assembly 113, the controller 112 being electrically connected with the temperature sensor 111 and the oil amount adjusting assembly 113; and wherein one end of the oil amount adjusting assembly 113 is arranged in communication with the oil pool 12, and the lubricating oil can flow from the oil pool 12 into the oil amount adjusting assembly 113, and the oil amount adjusting assembly 113 is used for adjusting the oil amount in the oil pool 12.

[0036] The oil pool 12 contains lubricating oil for lubricating the electric drive system, and a temperature sensor 111 is arranged on the side wall of the oil pool 12 to monitor the working oil temperature of the oil pool in real time.

[0037] The electric drive device 11 comprises a controller 112 and an oil amount adjusting assembly 113, the controller 112 being electrically connected with the temperature sensor 111 and the oil amount adjusting assembly 113 to receive the oil temperature signal and control the working mode of the oil amount adjusting assembly 113. One end of the oil amount adjusting assembly 113 is arranged in communication with the oil pool 12, and the oil amount adjusting assembly 113 can adjust the amount of lubricating oil in the oil pool 12 according to the instruction of the controller 112.

[0038] By dynamically adjusting the amount of lubricating oil in the oil pool 12 through the oil amount adjusting assembly 113, the application effectively reduces the oil stirring loss of the electric drive system under high-speed high-temperature working conditions, significantly improves the overall efficiency of the electric drive system, and not only improves the efficiency of the electric drive system, but also effectively avoids the frequent start of the system overheating protection mechanism caused by the excessively high oil temperature, prolongs the working time of high-torque output, and further enhances the power performance of the vehicle. The application solves the problem in the prior art that the amount of lubricating oil is fixed under different working conditions of the electric drive system, resulting in large oil stirring loss and low efficiency under high-speed high-temperature working conditions.

[0039] Specifically, the oil amount adjusting assembly 113 comprises: an oil amount adjuster cylinder body 1133, the inside of the oil amount adjuster cylinder body 1133 having a containing cavity, the bottom of the oil amount adjuster cylinder body 1133 being provided with an oil port 1134, and the oil amount adjuster cylinder body 1133 being arranged in communication with the oil pool 12 through the oil port 1134; an electric machine 1131, the electric machine 1131 being electrically connected with the controller 112; and a piston 1132, the two ends of the piston 1132 being arranged in abutment with the side wall of the oil amount adjuster cylinder body 1133, and the electric machine 1131 controlling the piston 1132 to reciprocate along the length direction of the oil amount adjuster cylinder body 1133, so that the lubricating oil flows between the containing cavity and the oil pool 12. Through the precisely designed oil amount adjusting assembly 113, combined with the temperature sensor 111 and the intelligent controller 112, the application realizes automatic adjustment of the oil amount according to the oil temperature change of the oil pool 12 of the electric drive system, not only improves the efficiency under high-speed working conditions, but also guarantees the lubrication under low-speed working conditions.

[0040] The oil regulator cylinder 1133 is designed as a closed cylindrical container with an internal cavity for temporarily storing the lubricating oil extracted from the oil pool 12. The material of the cylinder is selected to have high temperature resistance, corrosion resistance, and high strength to adapt to various complex working conditions.

[0041] The oil regulator cylinder 1133 is designed as a closed cylindrical container with an internal cavity for temporarily storing the lubricating oil extracted from the oil pool 12. The material of the cylinder is selected to have high temperature resistance, corrosion resistance, and high strength to adapt to various complex working conditions.

[0042] Alternatively, in this scheme, the oil inlet and outlet can be designed as the same port, i.e., sharing the same channel. This design simplifies the structure of the oil quantity regulating assembly, reduces manufacturing costs and installation space requirements. When the piston moves inward, the port acts as an oil inlet, introducing oil quantity into the oil quantity regulator cylinder; when the piston moves outward, the port acts as an oil outlet, discharging oil quantity to the oil pool. This scheme realizes the bidirectional regulation of oil quantity through the reciprocating movement of the piston and the one-way valve design of the oil port.

[0043] In another embodiment, the oil inlet and outlet can also be independently arranged at both ends or different positions of the oil quantity regulator cylinder. Independent oil inlet and outlet can also improve the sealing and reliability of the oil quantity regulator, reducing the risk of oil leakage. The oil inlet and outlet can be designed as temperature control valves that automatically adjust the opening and closing state according to the oil temperature of the oil pool. The temperature control valve can intelligently determine whether to open the oil inlet to increase the oil quantity or open the oil outlet to reduce the oil quantity according to the oil temperature signal, thereby realizing automatic oil quantity regulation. The controller of the temperature control valve can be independently designed to specifically monitor the oil temperature of the oil pool and control the opening and closing of the temperature control valve. The control logic of the temperature control valve can also be integrated into the existing controller 112 of the electric drive system.

[0044] The motor 1131, as the power source of the oil quantity regulating assembly 113, is electrically connected to the controller 112, and its rotation direction and speed are controlled by the controller in real time according to the collected oil temperature signal.

[0045] In this embodiment, the motor 1131 can be selected from types such as stepper motor and servo motor to achieve precise displacement control of the piston 1132. The motor needs to have high response speed and high precision positioning capability to quickly respond to oil quantity regulation requirements.

[0046] The piston 1132 is installed in the oil regulator cylinder 1133, and the two ends are in close contact with the cylinder wall to ensure that there is no leakage during reciprocating motion. The reciprocating motion of the piston 1132 is driven by the motor 1131. When the motor 1131 rotates forward, the piston 1132 moves inward to the cylinder, and absorbs the lubricating oil in the oil pool 12; when the motor reverses, the piston 1132 moves outward to the cylinder, and the lubricating oil in the containing cavity is squeezed back to the oil pool 12.

[0047] It should be further pointed out that the reciprocating motion of the piston can also be realized by hydraulic system and pneumatic system. The hydraulic system uses the pressure of oil to drive the piston to move, which is especially suitable for the environment where there is oil near the oil pool. The same oil can be used as power and adjustment object to realize the integration and simplification of the system. The pneumatic system uses compressed gas as power source, and changes the gas pressure to drive the piston to move in the oil regulator cylinder. This way is suitable for occasions that require fast response or where oil power regulation is limited, such as environments that need to avoid oil leakage.

[0048] Optionally, in this scheme, the change of the oil amount of the oil amount regulating assembly 113 can be in the form of step change or in the form of stepless continuous change.

[0049] In the step change mode, the movement of the piston is set to multiple fixed steps, and each time the oil amount is adjusted, the piston moves one or more steps to realize segmented adjustment of the oil amount. This way is suitable for scenes where the oil amount adjustment speed is not high, but the adjustment accuracy is required.

[0050] In the stepless continuous change mode, the movement of the piston can realize stepless adjustment, and the increase or decrease of the oil amount can be a continuous process. This way provides higher flexibility and accuracy, and is suitable for working conditions that require real-time and accurate adjustment of oil amount, such as fine adjustment of oil amount according to oil temperature during high-speed driving of vehicles.

[0051] In a specific embodiment, assuming that an electric vehicle encounters the problem of abnormal temperature rise of the oil pool 12 when driving at high speed, at this time the temperature sensor 111 detects that the oil temperature exceeds T1, and the signal is transmitted to the controller 112. After receiving the signal, the controller immediately starts the oil quantity adjusting assembly 113 into working mode M1, and sends a positive rotation instruction to the motor 1131. The motor 1131 rotates forward, driving the piston 1132 to move forward inside the oil quantity regulator cylinder 1133. Due to the sealing of the piston, this movement generates negative pressure inside the oil quantity regulator cylinder 1133, and the lubricating oil in the oil pool 12 is sucked into the containing cavity of the oil quantity regulator cylinder 1133 through the oil port 1134, thereby reducing the amount of lubricating oil in the oil pool, reducing the oil stirring loss, and thus reducing the oil temperature and improving the operating efficiency of the electric drive system. When the vehicle speed decreases and the oil temperature drops below T2, the controller 112 again starts the oil quantity adjusting assembly 113 into working mode M2, at this time the motor 1131 rotates in reverse, pushing the piston 1132 to move backward, and the lubricating oil in the containing cavity is squeezed out back to the oil pool 12, ensuring sufficient lubrication of the electric drive system during low-speed driving, and meeting the lubrication requirements under low vehicle speed and low working oil temperature.

[0052] According to another aspect of the present application, as shown in Figure 2 A control method for controlling the above-mentioned electric drive system to adjust the oil quantity in the oil pool is provided, and the control method comprises the following steps:

[0053] Step S102, obtaining an oil temperature signal of the oil pool, wherein the oil temperature signal is collected by a temperature sensor;

[0054] Step S104, obtaining the driving speed of the vehicle;

[0055] In this embodiment, the real-time driving speed information of the vehicle needs to be obtained, which is usually realized by a wheel speed sensor or other speed detection device of the vehicle, and the speed information is transmitted to the controller 112.

[0056] Step S106, determining whether the oil temperature signal meets the preset condition based on the driving speed, and generating a judgment result when it is determined that the oil temperature signal meets the preset condition;

[0057] Step S108, generating a control strategy set based on the judgment result.

[0058] The method is applied to the electric drive system mentioned above. By real-time acquisition and analysis of the oil temperature signal in the oil pool 12 and the vehicle speed, the working mode of the oil amount adjusting assembly 113 can be intelligently adjusted, and the amount of lubricating oil in the oil pool 12 is dynamically adjusted. This method effectively solves the problem of oil stirring loss caused by excessive lubricating oil under high-speed and high-temperature working conditions, and improves the efficiency and reliability of the electric drive system during high-speed operation. At the same time, it ensures that the oil amount is sufficient under low-speed and low-temperature conditions, meets the lubrication demand of the electric drive system, and avoids wear and low efficiency caused by insufficient oil amount. Through the generation and implementation of the control strategy set, the operation of the electric drive system is more intelligent and refined, not only optimizing oil management and reducing oil stirring loss, but also prolonging the high-torque working time by delaying the start of the over-temperature and torque limiting control strategy, and enhancing the power performance of the vehicle.

[0059] Specifically, based on the judgment result, the control strategy set is generated, including: when it is determined that the driving speed is high and the oil temperature signal exceeds the preset first temperature threshold, a first control strategy is generated; when it is determined that the driving speed is low and the oil temperature signal is lower than the preset second temperature threshold, a second control strategy is generated.

[0060] When the vehicle is in a high-speed driving state (defined as Vh>V1 threshold, where Vh is the current driving speed of the vehicle, and V1 threshold is a preset high-speed threshold), and the oil temperature signal in the oil pool 12 exceeds the preset first temperature threshold T1 (T1 is the maximum allowable oil temperature for normal operation of the electric drive system), the controller 112 will generate a first control strategy. Under this strategy, the amount of oil in the oil pool 12 is reduced to reduce the oil stirring loss under high-speed working conditions, thereby improving the efficiency of the electric drive system, and also helping to naturally cool the oil temperature.

[0061] When the vehicle is in a low-speed driving state (defined as Vl<V2 threshold, where Vl is the current driving speed of the vehicle, and V2 threshold is a preset low-speed threshold), and the oil temperature signal in the oil pool 12 is lower than the preset second temperature threshold T2 (T2 is the minimum allowable oil temperature for normal operation of the electric drive system), the controller 112 will generate a second control strategy. Under this strategy, the amount of oil in the oil pool 12 is increased to ensure that the lubrication demand of the electric drive system under low-speed and low-temperature conditions is met.

[0062] In a specific embodiment, assuming that a certain electric vehicle is driving on a highway, the real-time driving speed Vh of the vehicle reaches 100 km / h, and the oil temperature signal of the oil pool 12 shows T=105°C, which has exceeded the preset first temperature threshold T1=100°C. At this time, the controller 112 recognizes that the vehicle is in a high-speed driving state, and the oil temperature signal exceeds the first temperature threshold, so the first control strategy is generated. According to the first control strategy, the amount of oil in the oil pool 12 is reduced. This process effectively reduces the oil stirring loss during high-speed driving, improves the working efficiency of the electric drive system, and promotes the decrease of the oil temperature.

[0063] In another embodiment, when the same vehicle is running at a low speed on a city road, the real-time running speed V_l drops to 30 km / h, and the oil temperature signal of the oil pool 12 is T = 75°C, which is lower than the second temperature threshold T2 = 80°C. At this time, the controller 112 identifies that the vehicle is running at a low speed, and the oil temperature signal is lower than the second temperature threshold, and generates a second control strategy. Under this strategy, the oil amount in the oil pool 12 is increased, which ensures the lubrication requirement of the electric drive system at low speed and low temperature, and maintains the normal operation of the system.

[0064] Specifically, when the running speed is determined to be high speed and the oil temperature signal exceeds the first temperature threshold, the first control strategy is generated, including: controlling the electric drive device to execute a first working mode under the condition that the oil temperature signal is determined to exceed the first temperature threshold, wherein the first working mode is used to reduce the oil in the oil pool to a first preset oil amount; obtaining the oil temperature signal in the oil pool or the oil suction amount in the electric drive device; and controlling the electric drive device to stop running under the condition that the oil temperature signal is determined to be lower than the first temperature threshold or the oil suction amount is greater than a third preset oil amount.

[0065] When the vehicle running speed Vh exceeds the preset high speed threshold V1, and the oil temperature signal T of the oil pool 12 is lower than the second temperature threshold T2, the controller 112 identifies that the system enters a low speed and low temperature working condition, and generates a second control strategy. According to the second control strategy, the electric drive device executes a first working mode, i.e., reduces the oil amount in the oil pool 12 to a first preset oil amount N1, N1 is the optimal value of the oil amount under the preset high speed running condition, so as to reduce the oil stirring loss and improve the system efficiency. During the execution of the first working mode, the temperature sensor 111 continuously monitors the oil temperature signal of the oil pool 12, and the controller 112 also monitors the oil suction amount of the oil amount adjusting assembly 113. Once the oil temperature signal T is lower than the first temperature threshold T1, or the oil suction amount accumulates more than a third preset oil amount N2 (N2 is the maximum oil discharge amount of the oil amount adjusting assembly 113 in one cycle), a stop instruction is generated to stop the electric drive device from running, so as to terminate the first working mode, and prevent the system efficiency from being reduced or the oil temperature from abnormally fluctuating due to excessive oil amount adjustment.

[0066] In a specific embodiment, it is assumed that an electric vehicle is running at a high speed in summer, and the vehicle speed is 120 km / h, which is higher than the preset high-speed threshold 100 km / h. At the same time, the oil temperature signal of the oil pool 12 is 115°C, which exceeds the preset first temperature threshold 105°C, indicating that the electric drive system is in a high-speed high-temperature working condition. At this time, the control electric drive device executes the first working mode, i.e., the oil quantity reduction mode to reduce the oil stirring loss. The oil quantity in the oil pool 12 is gradually reduced until the oil quantity is reduced to the first preset oil quantity N1, which is the optimal value of the oil quantity under the preset high-speed running condition to reduce the oil stirring loss and improve the system efficiency. During the entire execution process of the first working mode, the temperature sensor 111 continuously detects the oil temperature signal of the oil pool 12 to ensure that the oil temperature is stably reduced. At the same time, the controller 112 monitors the oil suction quantity of the oil quantity adjusting assembly 113 in real time, and when the oil temperature signal T is lower than 105°C or the oil suction quantity reaches the third preset oil quantity N2, the controller 112 immediately stops the operation of the electric drive device to avoid excessive oil quantity adjustment to reduce the system efficiency or abnormal fluctuation of the oil temperature.

[0067] Specifically, when it is determined that the running speed is low and the oil temperature signal is lower than the preset second temperature threshold, a second control strategy is generated, including: in a case where it is determined that the oil temperature signal is lower than the preset second temperature threshold, controlling the electric drive device to execute a second working mode, wherein the second working mode is used to increase the oil quantity in the oil pool to a second preset oil quantity. Obtaining an oil temperature signal in the oil pool or an oil discharge quantity in the electric drive device; in a case where it is determined that the oil temperature signal exceeds the second temperature threshold or the oil discharge quantity is greater than a third preset oil quantity, controlling the electric drive device to stop running.

[0068] When the vehicle running speed Vl is reduced to be lower than the preset low-speed threshold V2, and the oil temperature signal T of the oil pool 12 is lower than the preset second temperature threshold T2, the controller 112 recognizes that the system enters a low-speed low-temperature working condition, and generates a second control strategy. According to the second control strategy, the electric drive device executes a second working mode, i.e., increases the oil quantity of the oil pool 12 to N0, N0 being the second preset oil quantity required by the electric drive system to ensure effective lubrication at low speed. During the execution of the second working mode, the temperature sensor 111 continuously monitors the oil temperature signal of the oil pool 12, and at the same time, the controller 112 also monitors the oil discharge quantity of the oil quantity adjusting assembly 113. Once the oil temperature signal T exceeds the second temperature threshold T2, or the cumulative oil discharge quantity exceeds the third preset oil quantity N2 (N2 being the maximum oil discharge quantity of the oil quantity adjusting assembly 113 in one cycle), a stop instruction is immediately generated to stop the operation of the electric drive device, thereby terminating the second working mode to prevent excessive increase of the oil quantity or accidental increase of the oil temperature. It needs to be further explained that in the present scheme, N2=N0-N1, i.e., the third preset oil quantity = the second preset oil quantity - the first preset oil quantity.

[0069] In a specific embodiment, assume that an electric vehicle is driving on urban roads in winter at a low speed, and the vehicle speed is V1=20km / h, which is lower than the preset low-speed threshold V2threshold=40km / h. At the same time, the oil temperature signal T of the oil pool 12 is 70°C, which is lower than the preset second temperature threshold T2=75°C. The control electric drive device executes the second working mode to gradually increase the oil amount in the oil pool 12 until the second preset oil amount N0 is reached. During the entire execution of the second working mode, the temperature sensor 111 continuously detects the oil temperature signal of the oil pool 12 to ensure that the oil temperature does not rise unexpectedly. At the same time, the oil discharge amount of the oil amount adjusting assembly 113 is monitored, and when the oil discharge amount reaches the third preset oil amount N2, the controller 112 will automatically stop the motor 1131 to prevent excessive oil supplement and increase the system burden or abnormal oil temperature.

[0070] Specifically, in the case where the oil temperature signal exceeds the preset first temperature threshold, the control electric drive device executes the first working mode, including: in the case where the oil temperature signal exceeds the preset first temperature threshold, controlling the motor to rotate forward, thereby driving the piston to move away from the oil pool and causing the lubricating oil in the oil pool to flow into the oil amount regulator cylinder. In the case of high speed and high temperature, the present application reduces the amount of lubricating oil in the oil pool by intelligently controlling the forward rotation of the motor and driving the piston to move, thereby successfully reducing the oil stirring loss during the operation of the electric drive system. This measure not only improves the efficiency of the electric drive system, but also helps to improve the heat dissipation performance of the system, prolong the service life of the system, and enhance the performance stability of the vehicle in hot weather and high-speed driving conditions.

[0071] When the temperature sensor 111 detects that the oil temperature signal T of the oil pool 12 is higher than T1, the signal is transmitted to the controller 112. The controller sends a forward rotation instruction of the motor 1131 according to the preset control logic. After receiving the forward rotation instruction from the controller 112, the motor 1131 starts to rotate forward. The motor 1131 converts the rotary motion into linear motion through transmission devices such as screws or gears, and drives the piston 1132 to move along the axis direction of the oil amount regulator cylinder 1133 to the inside of the oil amount regulator cylinder 1133, i.e. away from the oil pool 12. With the movement of the piston 1132, a negative pressure area is formed in the inside of the oil amount regulator cylinder 1133, and the lubricating oil in the oil pool 12 is passively sucked into the accommodating cavity of the oil amount regulator cylinder 1133 through the oil port 1134, thereby reducing the oil amount of the oil pool 12. The amount of lubricating oil sucked in is related to factors such as the stroke of the piston 1132 and the rotation speed of the motor 1131. During the execution of the first working mode, the temperature sensor 111 continuously monitors the oil temperature signal T of the oil pool 12. Once the oil temperature signal T is lower than T1, or the oil amount adjusting assembly 113 reaches the preset maximum oil suction amount N2, the controller 112 will generate a stop instruction to interrupt the forward rotation of the motor 1131, and the piston 1132 stops moving, thereby terminating the lubricating oil suction process and preventing the oil amount from being too low or excessively adjusted.

[0072] In a specific embodiment, assume that an electric vehicle is driving on a highway at a speed of 120 km / h in hot weather, and the temperature sensor 111 detects that the oil temperature signal T in the oil pool 12 is 110°C, which exceeds the preset first temperature threshold T1 = 105°C. At this time, the controller 112 determines that the vehicle is in a high-speed high-temperature working condition, and immediately starts the first working mode. After receiving the positive rotation instruction, the motor 1131 starts to rotate and drives the piston 1132 to move outward along the axis direction of the oil quantity regulator cylinder 1133, i.e., away from the oil pool 12. The moving piston 1132 generates a negative pressure area in the oil quantity regulator cylinder 1133, and the lubricating oil in the oil pool 12 starts to be sucked into the containing cavity of the oil quantity regulator cylinder 1133 through the oil port 1134, and the oil quantity in the oil pool 12 decreases. The whole process continues until the oil temperature signal T drops below 105°C, or the cumulative oil suction amount of the motor 1131 reaches N2. At this time, the controller 112 generates a stop instruction, the motor 1131 stops rotating, the position of the piston 1132 is fixed, and the first working mode ends. Through this process, the oil temperature during high-speed driving is effectively reduced, the oil stirring loss is reduced, and the overall efficiency of the electric drive system is improved.

[0073] Specifically, in the case where the oil temperature signal is determined to be lower than the preset second temperature threshold, the electric drive device is controlled to execute the second working mode, including: in the case where the oil temperature signal is determined to be lower than the preset second temperature threshold, the motor is controlled to reverse, thereby driving the piston to move close to the oil pool, and the lubricating oil in the oil quantity regulator cylinder is discharged into the oil pool. In a low-speed low-temperature environment, the second working mode of the present application effectively increases the amount of lubricating oil in the oil pool by reversing the motor and moving the piston, making up for the insufficient lubrication demand under low-temperature conditions. This not only improves the reliability of the electric drive system in cold weather, but also helps to reduce the friction loss during cold start, indirectly improving the overall performance and driving comfort of the vehicle.

[0074] When the temperature sensor 111 detects that the oil temperature signal T of the oil pool 12 is lower than the second temperature threshold T2, the signal is transmitted to the controller 112. The controller determines that the vehicle is in a low-speed low-temperature working condition, and immediately sends an instruction to reverse the motor 1131. After receiving the reverse instruction from the controller 112, the motor 1131 starts to rotate in the opposite direction. The motor 1131 converts the rotary motion of the motor into linear motion through internal gears or lead screws, etc. transmission device, drives the piston 1132 to move along the axis direction of the oil quantity regulator cylinder 1133 to the oil pool 12, i.e., close to the oil pool 12. With the action of the piston 1132 moving close to the oil pool 12, the pressure inside the oil quantity regulator cylinder 1133 increases, forcing the lubricating oil in the cylinder to be discharged back to the oil pool 12 through the oil port 1134, thereby increasing the oil quantity in the oil pool 12. The discharge amount of lubricating oil depends on the stroke of the piston 1132 and the rotation speed of the motor 1131.

[0075] In the second working mode, the temperature sensor 111 continues to monitor the oil temperature signal T of the oil pool 12. Once the oil temperature signal T rises to the second temperature threshold T2 or above, or the oil discharge amount of the oil amount adjusting assembly 113 reaches the third preset oil amount N2, the controller 112 will generate a stop instruction to cut off the reverse power supply of the motor 1131, and the piston 1132 stops moving, thereby avoiding excessive oil amount or unnecessary oil temperature rise.

[0076] In a specific embodiment, it is envisaged that on a cold winter morning, an electric vehicle is slowly driving in an urban area, and the vehicle driving speed is only 20 km / h, which is much lower than the high-speed threshold. At this time, the temperature sensor 111 detects that the oil temperature signal T in the oil pool 12 is only 65°C, which is lower than the second temperature threshold T2 = 70°C. The controller 112 determines that the vehicle is in a low-speed and low-temperature working condition, and quickly starts the second working mode. The motor 1131 starts to receive the reverse instruction, rotates reversely and drives the piston 1132 to move towards the oil pool 12 through the transmission mechanism. Due to the movement of the piston 1132, the lubricating oil in the oil amount adjuster cylinder 1133 is extruded, discharged back to the oil pool 12 through the oil port 1134, and the oil amount of the oil pool 12 gradually increases from N1 to N0 to meet the lubrication demand under the low-temperature condition. When the oil temperature signal T reaches 70°C or the oil discharge amount of the motor 1131 accumulates to N2, the controller 112 issues a stop instruction, the motor 1131 stops reversing, and the position of the piston 1132 is fixed, thereby terminating the oil discharge process. This control process ensures that the electric drive system is fully lubricated under low-temperature and low-speed working conditions, avoids insufficient lubrication due to too low oil temperature, and enhances the stability and service life of the electric drive system.

[0077] Specifically, the control method further comprises: in a case where it is determined that the oil temperature signal is between the first temperature threshold and the second temperature threshold, generating a third control strategy, the third control strategy being used to control the oil amount in the oil pool to remain unchanged.

[0078] The controller 112 continuously receives the oil temperature signal T from the temperature sensor 111. When T is between T1 and T2, i.e. the oil temperature is in the normal working range, the controller identifies the current working condition as a normal state. After confirming that the oil temperature signal T is between the two thresholds, the controller 112 generates a third control strategy, the core of which is to maintain the state of the oil amount adjuster and keep the oil amount in the oil pool 12 at the second preset oil amount N0 level, avoiding unnecessary oil amount adjustment operation. According to the third control strategy, the controller 112 does not send any rotation instruction to the motor 1131. The motor 1131 remains in a stationary state, neither rotates forward nor reverses, ensuring that the piston 1132 does not move, and the oil amount in the oil pool 12 is maintained, neither increasing nor decreasing.

[0079] Although the motor 1131 and the piston 1132 are in a stationary state, the controller 112 still needs to continuously monitor the oil amount in the oil pool 12 to ensure that the oil amount does not suddenly change due to other reasons. If the oil amount abnormally decreases or increases, the controller will automatically adjust to the first control strategy or the second control strategy to maintain the appropriate oil amount and the high efficiency of the electric drive system.

[0080] In a specific embodiment: assuming that an electric vehicle is driving in a mild climate condition in spring, the vehicle speed is 70 km / h, and the oil temperature signal T of the oil pool 12 is stabilized at 90°C, which is exactly between the preset first temperature threshold T1 = 100°C and the second temperature threshold T2 = 80°C. The controller 112 identifies that the vehicle is in a normal working condition according to the oil temperature signal and generates the third control strategy, i.e., the oil amount maintaining strategy. Under this strategy, the controller 112 does not issue a start instruction for the motor 1131, and the motor remains stationary, and the piston 1132 also remains stationary. The oil amount N in the oil pool 12 is at the N0 level, which will not decrease to N1 (decrease in oil amount) due to high speed and high temperature, nor will it increase to more than N0 (increase in oil amount) due to low speed and low temperature. The electric drive system operates under the normal oil amount, which not only ensures the lubrication effect but also avoids the oil stirring loss, and the system efficiency and stability reach the best balanced state.

[0081] The third control strategy effectively avoids unnecessary oil amount adjustment and reduces the energy consumption and mechanical wear of the electric drive system by keeping the motor 1131 and the piston 1132 in a stationary state when the oil temperature signal T is in the normal working range. This not only helps to improve the long-term reliability of the electric drive system, but also indirectly improves the vehicle's endurance, providing users with a more economical and environmentally friendly driving experience.

[0082] According to another aspect of the present application, a vehicle is provided, comprising a control method of an electric drive system, the control method being the control method described above.

[0083] For ease of description, spatial relative terms such as "on", "above", "upper surface", "upper", etc. can be used herein to describe the spatial relationship between one device or feature and another device or feature as shown in the drawings. It should be understood that the spatial relative terms are intended to include different orientations in use or operation in addition to the orientation of the device described in the drawings. For example, if the device in the drawings is inverted, the device described as "above" or "on" other devices or structures will be positioned "below" or "under" the other devices or structures. Thus, the exemplary term "above" can include both "above" and "below" orientations. The device can also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatial relative descriptions used herein are interpreted accordingly.

[0084] It is also important to note that the use of the term "comprising" does not exclude other elements being present. Also, the use of the terms "a" and "an" do not exclude a plurality. Further, the use of the term "one" does not exclude the presence of more than one. Further, the use of the term "another" does not exclude the presence of more than one. Further, the use of the term "at least one" does not exclude the presence of more than one. Further, the use of the term "one" followed by a comma does not exclude the presence of more than one. Further, the use of the term "one" as the sole integer of a listing of two or more elements, such as "one of A and B", does not exclude the presence of more than one of A and B. Further, the use of the term "at least one", followed by a comma and preceded by "comprising" does not exclude the presence of more than one. Further, the use of the term "at least one", followed by a comma does not exclude the presence of more than one. Further, the use of the term "at least one", where the reference list following the comma contains two or more elements, does not exclude the presence of more than one of each of the elements of the list. Further, the use of the term "one" followed by a comma does not exclude the presence of more than one; and further, the use of the term "at least one" followed by a comma is not limited to one or more of the elements lacking any other element or elements.

[0085] In the above embodiments, the description of each embodiment focuses on different aspects. For the parts not described in detail in a certain embodiment, please refer to the relevant description of other embodiments.

[0086] The preferred embodiments of the present application have been described above with the specific details. Obviously, those skilled in the art can make various modifications and variations to the present application without departing from the spirit and scope of the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the scope of protection of the present application.

Claims

1. An electric drive system, characterized in that, include: An oil tank (12) contains lubricating oil, and a temperature sensor (111) is provided on the side wall of the oil tank (12). An electric drive unit (11) includes a controller (112) and a fuel quantity regulating component (113), wherein the controller (112) is electrically connected to both the temperature sensor (111) and the fuel quantity regulating component (113); One end of the oil quantity regulating component (113) is connected to the oil sump (12), and the lubricating oil can flow from the oil sump (12) into the oil quantity regulating component (113). The oil quantity regulating component (113) is used to regulate the amount of oil in the oil sump (12).

2. The electric drive system according to claim 1, characterized in that, The oil quantity regulating component (113) includes: The oil quantity regulator cylinder (1133) has an internal cavity and an oil port (1134) at the bottom. The oil quantity regulator cylinder (1133) is connected to the oil sump (12) through the oil port (1134). Motor (1131), which is electrically connected to controller (112); The piston (1132) has its two ends in contact with the side wall of the oil quantity regulator cylinder (1133). The motor (1131) controls the piston (1132) to reciprocate along the length of the oil quantity regulator cylinder (1133), thereby causing the lubricating oil to flow between the receiving cavity and the oil sump (12).

3. A control method for an electric drive system, the control method being used to control the amount of oil in the regulating oil sump of the electric drive system as described in any one of claims 1 to 2, characterized in that, The control method includes: The oil temperature signal in the oil tank is acquired, wherein the oil temperature signal is obtained by a temperature sensor; Obtain the vehicle's speed; Based on the driving speed, it is determined whether the oil temperature signal meets the preset conditions. If it is determined that the oil temperature signal meets the preset conditions, a determination result is generated. Based on the judgment result, a set of control strategies is generated.

4. The control method according to claim 3, characterized in that, Based on the judgment result, generating the control strategy set includes: When it is determined that the driving speed is high and the oil temperature signal exceeds a preset first temperature threshold, a first control strategy is generated. When the driving speed is determined to be low and the oil temperature signal is lower than a preset second temperature threshold, a second control strategy is generated.

5. The control method according to claim 4, characterized in that, When it is determined that the driving speed is high and the oil temperature signal exceeds a preset first temperature threshold, the first control strategy is generated, including: If the oil temperature signal is determined to exceed the preset first temperature threshold, the electric drive device is controlled to execute a first working mode, wherein the first working mode is used to reduce the amount of oil in the oil sump to a first preset amount. Acquire the oil temperature signal in the oil tank or the oil suction volume in the electric drive device; If the oil temperature signal is determined to be lower than the first temperature threshold or the oil intake is greater than the third preset oil intake, the electric drive device is controlled to stop operating.

6. The control method according to claim 4, characterized in that, When it is determined that the driving speed is low and the oil temperature signal is below a preset second temperature threshold, the second control strategy is generated, including: If the oil temperature signal is determined to be lower than the preset second temperature threshold, the electric drive device is controlled to execute a second working mode, wherein the second working mode is used to increase the amount of oil in the oil sump to a second preset amount of oil. Acquire the oil temperature signal in the oil tank or the oil discharge volume in the electric drive device; If the oil temperature signal exceeds the second temperature threshold or the oil discharge volume is greater than the third preset oil volume, the electric drive device is controlled to stop operating.

7. The control method according to claim 5, characterized in that, If the oil temperature signal is determined to exceed the preset first temperature threshold, the electric drive device is controlled to execute the first operating mode, including: When the oil temperature signal exceeds the preset first temperature threshold, the motor is controlled to rotate forward, thereby driving the piston away from the oil sump and causing the lubricating oil in the oil sump to flow into the oil quantity regulator cylinder.

8. The control method according to claim 6, characterized in that, If the oil temperature signal is determined to be lower than the preset second temperature threshold, the electric drive device is controlled to execute the second operating mode, including: If the oil temperature signal is determined to be lower than the preset second temperature threshold, the motor is controlled to reverse, thereby driving the piston to move closer to the oil sump, so that the lubricating oil in the oil quantity regulator cylinder is discharged into the oil sump.

9. The control method according to claim 8, characterized in that, The control method further includes: generating a third control strategy when the oil temperature signal is determined to be between the first temperature threshold and the second temperature threshold, the third control strategy being used to control the amount of oil in the oil tank to remain constant.

10. A vehicle, including a control method for an electric drive system, characterized in that, The control method is the control method according to any one of claims 3 to 9.

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