A performance improvement method for motor controller and new energy vehicle

Abstract

The present invention relates to a performance improvement method of a motor controller and a new energy vehicle, and belongs to the technical field of power systems of new energy vehicles. When the real-time temperature of a power module in a motor controller is greater than a preset first temperature threshold, a cooling demand is sent to a thermal management controller, and the thermal management controller responds to the cooling demand, controls the liquid cooling circulation system to circulate and dissipate heat, and feeds back the water temperature and the state of the water pump of the liquid cooling circulation system to the motor controller; when the motor controller determines that the water pump is in a high-speed start state, and the water temperature is lower than the set threshold, the maximum output capacity of the drive motor is maintained, and the control linkage between the motor controller, the thermal management controller and the liquid cooling circulation system is realized, and the output capacity of the drive motor is maintained according to the working state of the liquid cooling circulation system, thereby improving the power of the new energy vehicle.

Description

Technical Field

[0001] The invention relates to a performance improvement method for a motor controller and a new energy vehicle, belonging to the technical field of new energy vehicle power systems. Background Art

[0002] The motor controller is the power control component of new energy vehicles. Under conditions such as starting on a steep slope, wheel unsettling, and heavy-load climbing, the motor controller needs to output a large current to increase the output capacity of the drive motor and ensure the driving power of the vehicle. However, at this time, it is a stalled condition or a high-torque continuous output condition. The temperature of the power module in the motor controller rises rapidly, and cooling needs to be strengthened to maintain the output. When the temperature exceeds the controller's temperature resistance limit, the controller will actively limit the output capacity to protect the power module from damage.

[0003] In the prior art, there is no significant linkage between the motor controller of new energy vehicles and the cooling system of the entire vehicle, which results in the motor controller being unable to obtain information such as the working status of the liquid cooling system and the cooling water temperature, thereby limiting the output capacity of the new energy vehicle to a fixed time (for example, the upper limit time of stalling at peak capacity is 5s, or the peak output torque is a maximum of 30s, and this fixed time is based on the upper limit threshold of the cooling water temperature and the cooling system's rated working condition.) However, this is not conducive to the new energy vehicle's dynamic performance when starting on a steep slope or getting the tire out of trouble.

[0004] To this end, a cooling control method and control system for an electric vehicle is disclosed in a patent document with authorization announcement number CN115416465B, wherein the CAN communication status between the motor controller and the vehicle controller is detected, and the coolant temperature is obtained; if the CAN communication status is lost, or the coolant temperature is greater than a preset temperature value, the motor controller controls the water pump to solve the control of the cooling system during a communication failure. Although the linkage between the motor controller and the cooling system is achieved, it only simply triggers the cooling system and cannot obtain relevant information of the cooling system, resulting in a single linkage and still unable to get rid of the output capacity limitation of new energy vehicles. Summary of the invention

[0005] The purpose of the present invention is to provide a performance improvement method for a motor controller and a new energy vehicle, so as to solve the problem of limited output capacity of new energy vehicles, adjust the output power of the motor controller according to the current state of the liquid cooling circulation system of the new energy vehicle, and maximize the overall vehicle power performance of the new energy vehicle.

[0006] To achieve the above objectives, on the one hand, the present invention provides a method for improving the performance of a motor controller, comprising: When the real-time temperature of the power module in the motor controller is greater than a preset first temperature threshold, a cooling demand is sent to the thermal management controller, and the thermal management controller responds to the cooling demand, controls the liquid cooling circulation system to circulate and dissipate heat, and feeds back the water temperature and water pump status of the liquid cooling circulation system to the motor controller; When the motor controller determines that the water pump is in a high-speed start-up state and the water temperature is lower than a set threshold, the maximum output capacity of the drive motor is maintained.

[0007] Furthermore, in the above-mentioned method for improving the performance of the motor controller, the condition for maintaining the maximum output capacity of the driving motor also includes: when the real-time temperature of the power module in the motor controller is less than the tolerance upper limit threshold, the maximum output capacity of the driving motor is maintained.

[0008] Furthermore, in the above-mentioned method for improving the performance of the motor controller, the water pump is a CAN-controlled water pump, so that the CAN-controlled water pump utilizes the CAN network to feedback the status of the water pump.

[0009] Furthermore, in the above-mentioned method for improving the performance of the motor controller, the thermal management controller responds to the cooling demand, collects the water temperature of the water inlet of the motor controller through a water temperature sampling sensor, and determines the water temperature of the water inlet as the water temperature of the liquid cooling circulation system.

[0010] Furthermore, in the above-mentioned method for improving the performance of the motor controller, the motor controller calls a junction temperature estimation function to obtain the real-time temperature of the power module.

[0011] Furthermore, the performance improvement method of the motor controller further includes: When the real-time temperature of the power module in the motor controller exceeds the upper limit of the tolerance temperature, the output capacity of the drive motor is reduced.

[0012] On the other hand, the present invention also proposes a new energy vehicle, including a motor controller and a thermal management controller; When the real-time temperature of the power module in the motor controller is greater than a preset first temperature threshold, a cooling demand is sent to the thermal management controller, and the thermal management controller responds to the cooling demand, controls the liquid cooling circulation system to circulate and dissipate heat, and feeds back the water temperature and water pump status of the liquid cooling circulation system to the motor controller; If the motor controller determines that the water pump is in a high-speed start state and the water temperature is lower than a set threshold, the maximum output capacity of the drive motor is maintained.

[0013] Furthermore, for the above-mentioned new energy vehicles, the conditions for maintaining the maximum output capacity of the drive motor also include: When the real-time temperature of the power module in the motor controller is less than the tolerance upper limit threshold, the maximum output capacity of the drive motor is maintained.

[0014] Furthermore, in the above-mentioned new energy vehicle, the water pump is a CAN-controlled water pump, so that the CAN-controlled water pump utilizes the CAN network to feedback the status of the water pump.

[0015] Furthermore, in the above-mentioned new energy vehicle, the thermal management controller responds to the cooling demand, collects the water temperature of the water inlet of the motor controller through a water temperature sampling sensor, and determines the water temperature of the water inlet as the water temperature of the liquid cooling circulation system.

[0016] Furthermore, in the above-mentioned new energy vehicle, the motor controller calls the junction temperature estimation function to obtain the real-time temperature of the power module.

[0017] Furthermore, the above-mentioned new energy vehicle also includes: When the real-time temperature of the power module in the motor controller exceeds the upper limit of the tolerance temperature, the output capacity of the drive motor is reduced.

[0018] The beneficial effects of the present invention are as follows: when the real-time temperature of the power module in the motor controller is greater than a preset first temperature threshold, a cooling demand is sent to the thermal management controller, and the thermal management controller responds to the cooling demand, controls the liquid cooling circulation system to circulate and dissipate heat, and feeds back the water temperature and the state of the water pump of the liquid cooling circulation system to the motor controller; when the motor controller determines that the water pump is in a high-speed start-up state and the water temperature is lower than the set threshold, the maximum output capacity of the drive motor is maintained, the control linkage between the motor controller, the thermal management controller and the liquid cooling circulation system is realized, and the output capacity of the drive motor is maintained according to the working state of the liquid cooling circulation system, thereby improving the power of new energy vehicles. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a flow chart of a method for improving performance of a motor controller according to one aspect of the present invention; Figure 2 It is a flow chart of a method for improving performance of a motor controller in an actual application scenario according to one aspect of the present invention; Figure 3 It is a structural schematic diagram of devices such as a motor controller, a thermal management controller and a liquid cooling circulation system in a new energy vehicle in an actual application scenario of another aspect of the present invention. DETAILED DESCRIPTION

[0020] In order to make the purpose, technical solutions and advantages of the present invention more clear, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments.

[0021] The idea of ​​the invention is to realize the control linkage between the motor controller and the vehicle cooling system through the water pump status and the water temperature feedback of the liquid cooling circulation system, so as to achieve the adaptive activation of the cooling system of the new energy vehicle according to the driving scenario, improve the output capacity of the motor controller, and enhance the power of the new energy vehicle.

[0022] Method Example 1: like Figure 1 FIG. 1 is a flow chart of a method for improving the performance of a motor controller according to one aspect of the present invention, which includes step S11 and step S12. Specifically: Execute step S11, when the real-time temperature of the power module in the motor controller is greater than a preset first temperature threshold, send a cooling demand to the thermal management controller, the thermal management controller responds to the cooling demand, controls the liquid cooling circulation system to circulate and dissipate heat, and feeds back the water temperature and the state of the water pump of the liquid cooling circulation system to the motor controller; It should be noted that the real-time temperature of the power module refers to the real-time temperature of the power module obtained by the motor controller calling the junction temperature estimation function or by a temperature measuring instrument such as a thermometer. In the preferred embodiment of the present application, the motor controller preferably calls the junction temperature estimation function to obtain the real-time temperature of the power module; the first temperature threshold refers to the temperature threshold for controlling the opening of the liquid cooling circulation system. In actual application scenarios, the first temperature threshold can be set according to the needs of new energy vehicles, user needs, or driving scene needs, etc.; the liquid cooling circulation system includes but is not limited to a water pump, a coolant, an expansion water tank, a fan, a heat exchanger, etc. When the liquid cooling circulation system starts circulating heat dissipation, the water pump pumps the coolant in the expansion water tank into the motor controller, and the coolant enters the drive motor from the water outlet of the motor controller. The coolant flows out of the drive motor and then enters the heat exchanger. The coolant flows out of the heat exchanger and then enters the expansion water tank to complete the heat dissipation cycle. In particular, the connection sequence of the expansion water tank, the heat exchanger, and the water pump can be adjusted. The fan has low-voltage line PWM control, CAN control, low-voltage line control, and other methods.

[0023] The water pump can be a CAN-controlled water pump or a low-voltage line-controlled water pump. In a preferred embodiment of the present application, the water pump is preferably a CAN-controlled water pump, so that the CAN-controlled water pump uploads the status of the water pump via the CAN network; the status of the water pump includes but is not limited to an on / off status for indicating whether the water pump is turned on, and an operating status for indicating the operating status of the water pump.

[0024] The water temperature of the liquid cooling circulation system refers to the water temperature at any circulation sampling point in the cooling water path within the liquid cooling circulation system. It monitors the water temperature at the selected sampling point through the water temperature sampling sensor in response to the cooling demand by the thermal management controller. Moreover, for different circulation sampling points, respective corresponding set thresholds will be set for determining whether the water temperature is lower than the set threshold in subsequent steps. It should be noted that the set threshold will be set according to the sampling point position, new energy vehicle washing requirements, user requirements, etc. In the preferred embodiment of this application, it is preferred to collect the water temperature at the water inlet sampling point of the motor controller.

[0025] Step S12: When the motor controller determines that the water pump is in the high-speed operation state and the water temperature is lower than the set threshold, maintain the maximum output capacity of the drive motor.

[0026] Through steps S11 - S12, according to the cooling demand, control the liquid cooling circulation system to start circulating heat dissipation, and during the heat dissipation process, feedback the water temperature of the liquid cooling circulation system and the state of the water pump to the motor controller. While achieving the circulating heat dissipation of the liquid cooling circulation system, monitor the real-time heat dissipation situation to deeply understand the current working state of the motor controller, and when the preset conditions are met, maintain the maximum output capacity of the drive motor. This not only establishes a connection between the motor controller and the liquid cooling circulation system, but also influences and controls each other, prompting the drive motor to maintain the maximum output power and improving the power performance of new energy vehicles in various driving scenarios.

[0027] In a preferred embodiment of this application, the motor controller invokes the junction temperature estimation function to obtain the real-time temperature t1 of its internal power module; preferably, the first temperature threshold is T1 in the driving scenario on a large slope; when the real-time temperature t1 > the first temperature threshold T1, the motor controller sends a cooling demand to the thermal management controller; the thermal management controller responds to the cooling demand, sends a working instruction to the CAN water pump, and controls the liquid cooling circulation system to perform circulating heat dissipation, prompting the CAN water pump to pump the coolant in the expansion tank into the motor controller. The coolant enters the drive motor from the water outlet of the motor controller, flows out of the drive motor and then enters the heat exchanger, and then flows out of the heat exchanger and enters the expansion tank for the heat dissipation cycle of the motor controller. During this process, the CAN water pump feeds back to the CAN network that the water pump is currently in the high-speed operation state. The thermal management controller monitors the water temperature at the water inlet sampling point of the motor controller through the water temperature sampling sensor and feeds back the water temperature t2 at the water inlet to the CAN network; the motor controller obtains the water temperature t2 at the water inlet and the high-speed operation state of the water pump from the CAN network; preferably, the set threshold corresponding to the water temperature at the water inlet of the motor controller is T2, and when t2 < T2, the motor controller maintains the maximum output capacity of the drive motor.

[0028] Method Embodiment 2: Following the above embodiment of the present application, the conditions for maintaining the maximum output capacity of the drive motor also include: When the real-time temperature of the power module in the motor controller is lower than the upper tolerance limit, the maximum output capacity of the driving motor is maintained; here, the upper tolerance limit refers to the upper output capacity limit of the motor controller, which can be set according to the hardware performance and other properties of the motor controller to control the operating status of the motor controller in real time, avoid overload output of the motor controller, and improve output safety.

[0029] When the motor controller determines that the water pump is in the high-speed start-up state, the water temperature is lower than the set threshold, and the real-time temperature is lower than the upper tolerance threshold, the maximum output capacity of the drive motor is maintained to achieve high-energy output within the upper tolerance range of the motor controller, thereby improving the power of the new energy vehicle and meeting the operating requirements of various driving environments.

[0030] For example Figure 2 As shown, it is a flow chart of a performance improvement method of a motor controller in an actual application scenario according to one aspect of the present invention, wherein the motor controller has a power module junction temperature estimation function. When the vehicle is powered on, the motor controller calls the junction temperature to estimate the real-time temperature of the power module and maintains a preset fixed stall output capacity; when the real-time temperature of the power module does not reach the required cooling system start-up threshold (i.e., the first temperature threshold), the real-time temperature of the power module is continuously monitored; when the real-time temperature of the power module reaches the required cooling system start-up threshold, the motor controller sends a cooling demand to the thermal management controller; the thermal management controller performs a system self-check in response to the cooling demand to prevent the subsequent occurrence of liquid cooling circulation system startup failures caused by thermal management controller failures; when the thermal management controller self-checks abnormally, feedback is given to Motor controller; when the thermal management controller self-tests normally, the thermal management controller sends work instructions to the CAN-controlled water pump and fan, and collects the water temperature of the water inlet of the motor controller through the water temperature sampling sensor; the CAN-controlled water pump also feeds back the operating status to the CAN communication network, and the thermal management controller feeds back the water temperature of the water inlet to the CAN communication network; the motor controller checks whether the real-time temperature of the power module is less than the upper tolerance threshold, whether the operating status of the CAN-controlled water pump is turned on at a high speed, and whether the water temperature of the water inlet is lower than the set threshold; if the water inlet temperature is lower than the threshold, the water pump is on and the water pump is in a high speed state, and the temperature of the motor controller power module has not reached the allowable upper limit temperature, the motor controller is no longer limited by the preset stall time or peak torque time, but continues to maintain the maximum output capacity.

[0031] Method embodiment 3: On the other hand, a method for improving the performance of a motor controller provided by the present invention also includes: when the real-time temperature of the power module in the motor controller exceeds the upper tolerance limit temperature, reducing the output capacity of the driving motor, reducing the risk of the motor controller being burned at the upper tolerance limit, and improving the safety of the motor controller operation.

[0032] For example, when the water inlet temperature is lower than the threshold, the water pump is on and in high speed state, and the temperature of the motor controller power module has not reached the allowable upper limit temperature, the motor controller is no longer limited by the preset stall time or peak torque time, but continues to maintain the maximum output capacity until the real-time temperature of the junction temperature estimation power module in the motor controller exceeds the tolerance upper limit threshold, and the motor controller is derated.

[0033] At the same time, in actual application scenarios, after receiving the cooling demand information sent by the motor controller, the thermal management controller of the present invention provides low-voltage power supply and work instructions to the water pump and fan. During the entire liquid cooling circulation system heat dissipation process, the water pump working status, water pump speed, water inlet temperature and other information are sent to the CAN communication network for verification of the motor controller. The thermal management controller analyzes the water temperature in real time and sends it to the CAN communication network by setting a water temperature sampling sensor in the water inlet pipeline of the motor controller. The motor controller is liquid-cooled. After the water pump pumps the coolant into the motor controller and the drive motor, it enters the heat exchanger for heat dissipation.

[0034] Compared with the relevant industry, the present invention realizes hardware optimization such as CAN-controlled water pump and temperature detection of coolant inlet, as well as software control optimization among motor controller, thermal management controller, water pump and other systems, so as to achieve the goal of adaptively turning on the cooling system of new energy vehicles according to the driving environment, improve the output capacity of the motor controller, and enhance the power of the whole vehicle.

[0035] New energy vehicle embodiment 1: Another aspect of the present invention provides a new energy vehicle, including a motor controller and a thermal management controller; wherein, when the real-time temperature of the power module in the motor controller is greater than a preset first temperature threshold, a cooling demand is sent to the thermal management controller, and the thermal management controller responds to the cooling demand, controls the liquid cooling circulation system to circulate and dissipate heat, and feeds back the water temperature and the status of the water pump of the liquid cooling circulation system to the motor controller; when the motor controller determines that the water pump is in a high-speed start-up state and the water temperature is lower than the set threshold, the maximum output capacity of the drive motor is maintained.

[0036] For example Figure 3As shown, it is a structural schematic diagram of the motor controller, thermal management controller and liquid cooling circulation system in a new energy vehicle in an actual application scenario of another aspect of the present invention, wherein a CAN communication network is established between the power battery, the motor controller, the thermal management controller and the CAN-controlled water pump, and the motor controller obtains high voltage electricity from the power battery, and converts the DC high voltage electricity into three-phase AC electricity through the internal power module to drive the driving motor to work and provide power to the axle transmission and tires of the whole vehicle. A power module is provided in the motor controller, and the power module is connected to the drive motor so that the drive motor drives the axle to rotate and the tire. In addition, the power device in the motor controller uses junction temperature estimation to monitor the real-time temperature of the power module. A cooling water path is formed between the motor controller, the drive motor, the heat exchanger, the coolant and the CAN-controlled water pump. The thermal management controller collects the water temperature at the water inlet of the motor controller; and controls the fan through PWM to realize the performance improvement method of the above-mentioned motor controller, improve the output capacity of the motor controller, and improve the power of the whole vehicle.

Claims

1. A method for improving the performance of a motor controller, characterized in that: include: When the real-time temperature of the power module in the motor controller is greater than a preset first temperature threshold, a cooling demand is sent to the thermal management controller, and the thermal management controller responds to the cooling demand, controls the liquid cooling circulation system to circulate and dissipate heat, and feeds back the water temperature and water pump status of the liquid cooling circulation system to the motor controller; When the motor controller determines that the water pump is in a high-speed start-up state and the water temperature is lower than a set threshold, the maximum output capacity of the drive motor is maintained.

2. The method for improving the performance of a motor controller according to claim 1, characterized in that: The condition for maintaining the maximum output capacity of the driving motor also includes: when the real-time temperature of the power module in the motor controller is less than the tolerance upper limit threshold, the maximum output capacity of the driving motor is maintained.

3. The method for improving the performance of a motor controller according to claim 1, characterized in that: The water pump is a CAN-controlled water pump, so that the CAN-controlled water pump uses the CAN network to feedback the status of the water pump.

4. The method for improving the performance of a motor controller according to claim 1, characterized in that: In response to the cooling demand, the thermal management controller collects the water temperature of the water inlet of the motor controller through a water temperature sampling sensor, and determines the water temperature of the water inlet as the water temperature of the liquid cooling circulation system.

5. The method for improving the performance of a motor controller according to claim 1, characterized in that: The motor controller calls the junction temperature estimation function to obtain the real-time temperature of the power module.

6. The method for improving the performance of a motor controller according to any one of claims 1 to 5, characterized in that: Also includes: When the real-time temperature of the power module in the motor controller exceeds the upper limit of the tolerance temperature, the output capacity of the drive motor is reduced.

7. A new energy vehicle, characterized in that: Includes motor controller and thermal management controller; When the real-time temperature of the power module in the motor controller is greater than a preset first temperature threshold, a cooling demand is sent to the thermal management controller, and the thermal management controller responds to the cooling demand, controls the liquid cooling circulation system to circulate and dissipate heat, and feeds back the water temperature and water pump status of the liquid cooling circulation system to the motor controller; If the motor controller determines that the water pump is in a high-speed start state and the water temperature is lower than a set threshold, the maximum output capacity of the drive motor is maintained.

8. The new energy vehicle according to claim 7, characterized in that: The conditions for maintaining the maximum output capacity of the drive motor also include: When the real-time temperature of the power module in the motor controller is less than the tolerance upper limit threshold, the maximum output capacity of the drive motor is maintained.

9. The new energy vehicle according to claim 7, characterized in that: The water pump is a CAN-controlled water pump, so that the CAN-controlled water pump uses the CAN network to feedback the status of the water pump.

10. The new energy vehicle according to claim 7, characterized in that: In response to the cooling demand, the thermal management controller collects the water temperature of the water inlet of the motor controller through a water temperature sampling sensor, and determines the water temperature of the water inlet as the water temperature of the liquid cooling circulation system.

11. The new energy vehicle according to claim 7, characterized in that: The motor controller calls the junction temperature estimation function to obtain the real-time temperature of the power module.

12. The new energy vehicle according to any one of claims 7 to 11, characterized in that: Also includes: When the real-time temperature of the power module in the motor controller exceeds the upper limit of the tolerance temperature, the output capacity of the drive motor is reduced.

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