Motor controller for realizing ramp torque compensation, control method and electric vehicle

Abstract

The invention provides a motor controller for realizing ramp torque compensation, a control method and an electric vehicle. The motor controller is used for controlling a driving motor to output torque so as to drive wheels of the electric vehicle. In the process that the electric vehicle runs on the road surface with the gradient smaller than or equal to the preset gradient threshold value, the motor controller is specifically used for controlling the torque indicated by the torque signal output by one driving motor. When the electric vehicle runs on a ramp with the gradient larger than a preset gradient threshold value, the motor controller is specifically used for actively controlling one driving motor to adjust torque output. In other words, when the electric vehicle runs on the ramp, the motor controller can actively control the driving motor to adjust the torque output to achieve ramp torque compensation without being indicated by the whole vehicle controller, so that the vehicle speed of the electric vehicle when the electric vehicle passes through the ramp is maintained, and non-inductive ramp crossing is achieved.

Description

Technical Field

[0001] The present application relates to the field of vehicles, and in particular to a motor controller, a control method and an electric vehicle for realizing ramp torque compensation. Background Art

[0002] When a vehicle passes through an uphill or downhill section, if the driver does not operate the accelerator pedal, the vehicle's control system will not automatically adjust the power output of the vehicle as the road slope changes, which will cause the vehicle speed to fluctuate and affect the driver's driving experience. For vehicles equipped with a cruise control system (CCS), the vehicle can travel at the set target speed without the driver operating the accelerator pedal, thereby reducing the driver's driving fatigue. However, when a vehicle passes through an uphill or downhill section, this phenomenon is also prone to occur when the vehicle enters the ramp, and it is impossible to ensure that the vehicle passes the ramp at a constant speed, affecting driving comfort.

[0003] Therefore, how to reduce the speed fluctuation of the vehicle when passing through a slope to improve driving comfort is an urgent problem to be solved. Summary of the invention

[0004] The present application provides a motor controller, a control method and an electric vehicle for realizing slope torque compensation. When the vehicle is traveling on a slope, the motor controller actively adjusts the torque output of the drive motor to realize slope torque compensation. The control delay is short, and the vehicle can realize senseless slope crossing, thereby improving the handling performance of the entire vehicle.

[0005] In a first aspect, a motor controller for implementing ramp torque compensation is provided, the motor controller being used to control a drive motor to output torque to drive the wheels of an electric vehicle. When the electric vehicle is traveling on a road with a slope less than or equal to a preset slope threshold, the motor controller is specifically used to control the torque indicated by the output torque signal of the drive motor. When the electric vehicle is traveling on a slope with a slope greater than a preset slope threshold, the motor controller is specifically used to actively control the drive motor to adjust the torque output.

[0006] It can be understood that the motor controller provided in the embodiment of the present application can independently perform slope torque compensation. When it is detected that the electric vehicle is traveling on a slope with a slope greater than its slope, it can not be controlled according to the indication of the torque signal, but the torque to be output can be adjusted to directly perform torque compensation, which can shorten the control path and effectively reduce the control time of torque compensation.

[0007] It can be understood that the motor controller can be communicated with the slope sensor in the vehicle and obtain the slope of the current road surface through the slope sensor, or the motor controller also obtains the speed of the drive motor based on the motor speed signal provided by the resolver sensor to determine the slope of the current road surface, and then actively controls the drive motor to adjust the torque output when the vehicle enters a slope with a slope greater than a preset slope threshold.

[0008] It can be understood that different modes of the electric vehicle can correspond to different preset slope thresholds, so that the user experience can be further improved through differentiated preset slope threshold settings.

[0009] According to the application scheme, when an electric vehicle is driving on a slope, even if the driver does not actively adjust the opening of the accelerator pedal, the motor controller can actively control the drive motor to adjust the torque output to achieve slope torque compensation without the instruction of the vehicle controller, thereby maintaining the speed of the electric vehicle when passing through the slope, achieving non-sensing slope crossing, and further improving driving comfort. In addition, the slope torque compensation control can be closed-loop inside the motor controller, with a short control path and high real-time control.

[0010] In combination with the first aspect, in certain embodiments of the first aspect, when the electric vehicle is traveling uphill on the slope, the motor controller is specifically used to actively control the one drive motor to increase the torque output. When the electric vehicle is traveling downhill on the slope, the motor controller is specifically used to actively control the one drive motor to reduce the torque output.

[0011] It is understandable that when an electric vehicle travels from a road to an uphill section, the driving force required for the vehicle to move forward under the action of inertia is greater. Therefore, the motor controller needs to actively control the motor to increase the torque output so that the vehicle speed remains stable when traveling on the road and the slope.

[0012] It is understandable that when an electric vehicle travels from a road to a downhill section, the driving force required for the vehicle to move forward is reduced due to inertia, and if the driver does not actively intervene at this time, the excessive speed may affect driving safety. Therefore, the motor controller needs to actively control the motor to reduce the torque output so that the vehicle speed remains stable when traveling on the road and slope.

[0013] According to the solution of this application, the motor controller will specifically control the drive motor to adjust the torque output when the vehicle is going uphill or downhill, so that the power of the entire vehicle can ensure the stability of the vehicle speed, with simple control method and strong reliability.

[0014] In combination with the first aspect, in certain embodiments of the first aspect, during the process of the electric vehicle traveling uphill on the slope, the motor controller is specifically used to actively control the one drive motor to increase the torque output so that the torque output by the one drive motor is greater than the torque indicated by the torque signal. During the process of the electric vehicle traveling downhill on the slope, the motor controller is specifically used to actively control the one drive motor to reduce the torque output so that the torque output by the one drive motor is less than the torque indicated by the torque signal.

[0015] Among them, the torque signal can be generated by the vehicle controller based on the cruise control speed set by the driver, or it can be generated by the vehicle controller based on the opening of the accelerator pedal operated by the driver. It can be understood that when the vehicle is driving on a slope, due to the decoupling of the operation of the motor controller and the vehicle controller, the torque output by the motor controller to control the drive motor and the torque indicated by the torque signal will be different. At this time, the vehicle controller is actually not controlling the torque of the motor controller. Therefore, in one embodiment, the torque indicated by the torque signal output by the vehicle controller remains unchanged.

[0016] In these embodiments, when the electric vehicle is traveling uphill, the motor controller will actively control the drive motor to increase the torque output so that the torque actually output by the drive motor is greater than the torque indicated by the torque signal. When the electric vehicle is traveling downhill, the motor controller will actively control the drive motor to reduce the torque output so that the torque actually output by the drive motor is less than the torque indicated by the torque signal.

[0017] According to the solution of this application, when the vehicle is driving on a slope, the operation of the motor controller is decoupled from the vehicle controller, and the torque output by the drive motor can be actively controlled to be greater or less than the torque indicated by the torque signal, without waiting for the vehicle controller to send a torque signal again to adjust the torque output of the drive motor, and the control is more timely. In addition, the ramp torque compensation function of the motor controller can be used in both the vehicle automatic driving scenario and the driver manual driving scenario, and is highly practical.

[0018] In combination with the first aspect, in certain embodiments of the first aspect, in the process of actively controlling the one drive motor to adjust the torque output, the motor controller is specifically used to control the torque indicated by the one drive motor output torque signal in response to a change in the opening degree of the accelerator pedal of the electric vehicle being greater than a preset change value.

[0019] It can be understood that the change in the opening of the accelerator pedal of the electric vehicle is greater than the preset change value, which can be understood as the driver's expectation to adjust the driving speed of the electric vehicle by operating the opening of the accelerator pedal. At this time, the vehicle controller will generate an adjusted torque signal according to the adjusted opening of the accelerator pedal. Furthermore, if the adjusted torque signal is received during the process of actively controlling the drive motor to adjust the torque output, the motor controller will interrupt the ramp torque compensation function and control the drive motor output torque according to the adjusted torque signal, so that the power output of the vehicle is more in line with the driver's expectations.

[0020] According to the scheme of the present application, during the process of the motor controller performing slope torque compensation, the motor controller will also adjust the torque output by the drive motor according to the indication of the torque signal when the accelerator pedal operated by the driver is opened, so that the power output of the whole vehicle is more in line with the driver's expectations, further improving the controllability of the electric vehicle.

[0021] In combination with the first aspect, in certain embodiments of the first aspect, during the driving of the electric vehicle on the slope, the motor controller is specifically used to actively control the drive motor to adjust the torque output in response to the torque indicated by the torque signal remaining unchanged or the opening of the accelerator pedal remaining unchanged, and the speed of the drive motor indicated by the rotary transformer signal changing by a value greater than a preset value within a preset time period.

[0022] It can be understood that since the torque indicated by the torque signal remains unchanged or the opening of the accelerator pedal remains unchanged, the situation where the driver actively controls the acceleration or deceleration of the electric vehicle can be ruled out, avoiding misjudgment.

[0023] It can be understood that the preset amplitude can be a relatively small speed value, which can ensure that when the motor controller recognizes that the speed change value of the drive motor within a preset time is greater than the preset amplitude to perform active torque adjustment, the driver is basically unaware of the speed change of the electric vehicle. In other words, there is no need to set up an additional ramp sensor in the electric vehicle, and the motor controller can independently perform ramp detection based on the resolver signal, which can effectively reduce the complexity of communication and shorten the time it takes for the motor controller to obtain ramp information.

[0024] It should be noted that the motor controller can use a Sigma-Delta Analog-to-Digital Converter (SDADC) to sample the resolver signal, and its sampling rate can reach 2 MHz, and its sampling accuracy can reach 16 bits, and the acquired sampling parameters are reliable. In other words, there is no need to set up an additional ramp sensor in the electric vehicle, and the motor controller can use SDADC to effectively improve the sampling speed and accuracy of the motor speed of the sampling drive motor, thereby enhancing the real-time and accuracy of the motor controller in performing ramp torque compensation.

[0025] According to the present application, the motor controller can detect the ramp according to the rotation speed of the drive motor and control the drive motor to perform ramp torque compensation, thereby realizing the closed loop of the entire control process inside the motor controller, with high control bandwidth and small fluctuation. In addition, the motor controller can sample the resolver signal through SDADC to determine the ramp information, and the real-time and precision of the ramp information detection are higher, further enhancing the stability of the ramp torque compensation.

[0026] In combination with the first aspect, in certain embodiments of the first aspect, during the process of actively controlling the one drive motor to adjust the torque output, the motor controller is further used to control the one drive motor to reduce the torque output in response to the slip rate of the wheel driven by the one drive motor being greater than a preset slip rate. During the process of actively controlling the one drive motor to adjust the torque output, the motor controller is further used to control the one drive motor to increase the torque output in response to the slip rate of the wheel driven by the one drive motor being less than a preset slip rate.

[0027] Among them, the slip rate of the wheel can be understood as the proportion of the sliding component of the wheel during movement. When the adhesion of the road changes, the slip rate of the wheel will also change accordingly. A slip rate that is too high will cause the wheel to rotate but fail to effectively transmit driving force or braking force. A slip rate that is too low will cause the driving force or braking force transmitted by the wheel to be greater than expected, thereby affecting the steering ability and stability of the vehicle. Therefore, during the driving or steering process of the electric vehicle, the slip rate of the wheel needs to be controlled near the preset slip rate.

[0028] In these embodiments, while actively controlling the drive motor to adjust the torque output, the motor controller can also calculate the slip rate of the wheel driven by the drive motor based on the speed of the drive motor and the output torque of the drive motor, and further control the drive motor corresponding to the wheel to adjust the torque output, thereby ensuring the driving stability of the vehicle.

[0029] According to the scheme of the present application, the motor controller can determine the slip rate of the wheel by the speed and output torque of the driving motor. In this way, the observation of whether the wheel is slipping and the adjustment of the slip rate of the wheel are both realized inside the driving system, with shorter time delay, and can almost achieve microsecond (us) level rapid observation and millisecond (ms) level torque adjustment.

[0030] In combination with the first aspect, in certain embodiments of the first aspect, the one drive motor is used to drive the two front wheels of the electric vehicle, and the electric vehicle further comprises another drive motor for driving the two rear wheels of the electric vehicle. During the process of the electric vehicle traveling uphill on the slope, the motor controller is used to control the increase value of the torque output of the one drive motor to be smaller than the increase value of the torque output of the other drive motor. During the process of the electric vehicle traveling downhill on the slope, the motor controller is used to control the decrease value of the torque output of the one drive motor to be larger than the decrease value of the torque output of the other drive motor.

[0031] It can be understood that for electric vehicles with front and rear dual electric drive, when the electric vehicle is driving uphill on a slope, controlling the rear wheel load to be larger can more fully exert the driving force. At this time, the torque value increased by the drive motor controlled by another motor controller to drive the two rear wheels is greater than the torque value increased by the motor controller to drive the two front wheels.

[0032] It can be understood that for electric vehicles with front and rear dual electric drive, when the electric vehicle is driving downhill on a slope, controlling the front wheel load to be larger can more fully exert the driving force. At this time, the torque value reduced by the motor controller controlling the drive motor used to drive the two front wheels is greater than the torque value reduced by the other motor controller controlling the drive motor used to drive the two rear wheels.

[0033] According to the scheme of the present application, for electric vehicles with front and rear dual electric drives, the front drive motor and the rear drive motor can be controlled to adjust the torque output values ​​differentially when the vehicle is going uphill and downhill, so that the driving force of the entire vehicle can be more fully exerted, thereby more accurately achieving the vehicle's senseless slope crossing and further improving driving comfort.

[0034] In combination with the first aspect, in certain embodiments of the first aspect, the one drive motor is used to drive a left wheel of the electric vehicle, and the electric vehicle further comprises another drive motor for driving a right wheel coaxial with the one wheel. During the process of the electric vehicle driving uphill on the slope, the motor controller is used to control the increase value of the torque output of the another drive motor to be greater than the increase value of the torque output of the one drive motor in response to the angle of the steering wheel of the electric vehicle turning to the left being greater than a preset angle threshold. The motor controller is used to control the increase value of the torque output of the one drive motor to be greater than the increase value of the torque output of the another drive motor in response to the angle of the steering wheel of the electric vehicle turning to the right being greater than a preset angle threshold.

[0035] It can be understood that the preset turning angle threshold can be understood as a smaller turning angle, and the turning angle of the steering wheel of the electric vehicle greater than the preset turning angle threshold can be understood as the driver's desire to control the steering of the vehicle by operating the steering wheel. For the scenario of electric vehicles turning uphill, in the powertrain of the dual-motor architecture, the motor controller will determine the speed of the motor corresponding to the left wheel and the speed of the motor corresponding to the right wheel based on the resolver signal, and distribute the torque based on the speed of the motors on both sides, so that the actual yaw moment of the vehicle is better close to the expected yaw moment, ensuring lateral stability and improving steering performance.

[0036] Therefore, since the speed of the right motor is higher when the electric vehicle turns left, the motor controller controls the torque increase value of the right motor to be greater than the torque increase value of the left motor. Similarly, since the speed of the left motor is higher when the electric vehicle turns right, the motor controller controls the torque increase value of the left motor to be greater than the torque increase value of the right motor.

[0037] Similarly, during downhill driving of the vehicle, in response to the electric vehicle steering wheel turning leftward at an angle greater than a preset angle threshold, the motor controller is specifically used to control the reduction value of the torque output of another drive motor to be greater than the reduction value of the torque output of one drive motor. In response to the electric vehicle steering wheel turning rightward at an angle greater than a preset angle threshold, the motor controller is specifically used to control the reduction value of the torque output of one drive motor to be greater than the reduction value of the torque output of another drive motor.

[0038] According to the scheme of the present application, for an electric vehicle with a dual-motor architecture powertrain, when the vehicle turns on a slope, the motor controller can control the torque value adjusted by the drive motor used to drive the wheels turning to the outside to be greater than the torque value adjusted by the drive motor used to drive the wheels turning to the inside, thereby ensuring the lateral stability of the vehicle during the turning process and further improving the vehicle's handling.

[0039] In a second aspect, a control method for an electric vehicle is provided, the control method being used to control the drive system of the electric vehicle to adjust the torque output to achieve slope torque compensation when the electric vehicle is traveling on a slope, the control method comprising: at a first moment, in response to the electric vehicle traveling on a road with a slope less than or equal to a preset slope threshold, controlling the drive system to output torque to drive the wheels of the electric vehicle. At a second moment after the first moment, in response to the electric vehicle traveling on a slope with a slope greater than the preset slope threshold and the opening of the accelerator pedal of the electric vehicle remains unchanged, controlling the drive system to adjust the torque output.

[0040] In combination with the second aspect, in certain embodiments of the second aspect, the control method also includes, at the second moment, in response to the electric vehicle being driven on a slope having a slope greater than a preset slope threshold, the opening of the accelerator pedal of the electric vehicle remaining unchanged, and the electric vehicle operating in a forward gear, controlling the drive system to adjust the torque output.

[0041] It should be emphasized that in these embodiments, the drive system is controlled to perform slope torque compensation only when the vehicle is running in forward gear and passing through a slope. In other words, when the electric vehicle is running in reverse gear and passing through a slope, the vehicle control method will control the drive system to output torque according to the indication of the torque signal, thereby ensuring that the driver can perceive the slope of the road through the change in vehicle speed, thereby improving driving safety.

[0042] In combination with the second aspect, in certain embodiments of the second aspect, the control method includes: at the second moment, controlling the drive system to increase or decrease the torque output so that the torque output by the drive system is not equal to the torque indicated by the torque signal.

[0043] In combination with the second aspect, in certain embodiments of the second aspect, the control method further includes controlling the increase value of the torque output of the drive system to the two front wheels of the electric vehicle to be smaller than the increase value of the torque output of the drive system to the two rear wheels of the electric vehicle during the electric vehicle traveling uphill on the slope. Controlling the decrease value of the torque output of the drive system to the two rear wheels of the electric vehicle to be smaller than the decrease value of the torque output of the drive system to the two front wheels of the electric vehicle during the electric vehicle traveling downhill on the slope.

[0044] In combination with the second aspect, in certain embodiments of the second aspect, the control method further includes that during the uphill driving of the electric vehicle on the slope, in response to the steering wheel of the electric vehicle turning left at an angle greater than a preset angle threshold, the increase in the torque output of the drive system to the left wheel is actively controlled to be smaller than the increase in the torque output of the drive system to the right wheel. During the uphill driving of the electric vehicle on the slope, in response to the steering wheel of the electric vehicle turning right at an angle greater than a preset angle threshold, the increase in the torque output of the drive system to the right wheel is actively controlled to be smaller than the increase in the torque output of the drive system to the left wheel.

[0045] In combination with the second aspect, in certain embodiments of the second aspect, the control method also includes, at a third moment after the second moment, in response to the electric vehicle being driven on a slope having a slope greater than a preset slope threshold and a change in the opening of an accelerator pedal of the electric vehicle being greater than a preset change value, controlling the drive system to output the torque indicated by the torque signal.

[0046] In a third aspect, a controller is provided, wherein the controller is used to execute the control method as in the second aspect or any one of the embodiments of the second aspect.

[0047] In a fourth aspect, an electric vehicle is provided, comprising a drive system and a controller, wherein the drive system is used to drive the four wheels of the electric vehicle to rotate, and the drive system comprises a motor controller as described in the first aspect or any embodiment of the first aspect, wherein the controller is used to control the drive system to execute the control method described in any one of the second aspect or any embodiment of the second aspect.

[0048] As for the supplements and technical effects of the solutions provided in the second to fourth aspects above, please refer to the corresponding description of the first aspect and will not be repeated here. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] Figure 1 A schematic diagram of an electric vehicle 01 provided in an embodiment of the present application;

[0050] Figure 2 A schematic diagram of the structure of a drive system 10 provided in an embodiment of the present application;

[0051] Figure 3 A schematic diagram of the relationship between a road slope and a driving motor torque output provided in an embodiment of the present application;

[0052] Figure 4 A schematic diagram of the relationship between a preset slip ratio and a drive motor torque output provided in an embodiment of the present application;

[0053] Figure 5 A schematic diagram of the relationship between the front and rear dual electric drive torque output and the road surface provided in an embodiment of the present application;

[0054] Figure 6 A schematic diagram of the relationship between the front and rear dual electric drive torque output and the road surface provided in an embodiment of the present application;

[0055] Figure 7 A schematic diagram of a process for torque compensation on a slope of an electric vehicle provided in an embodiment of the present application. DETAILED DESCRIPTION

[0056] The technical solution in this application will be described below in conjunction with the accompanying drawings.

[0057] In the description of the embodiments of the present application, unless otherwise specified, “ / ” means or. For example, A / B can mean A or B. The “and / or” in this article is merely a way to describe the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone.

[0058] In the embodiments of the present application, prefixes such as "first" and "second" are used only to distinguish different description objects, and have no limiting effect on the position, order, priority, quantity or content of the described objects. The use of prefixes such as ordinal numbers to distinguish description objects in the embodiments of the present application does not constitute a limitation on the described objects. For the statement of the described objects, please refer to the description in the context of the claims or embodiments, and no unnecessary limitation should be constituted due to the use of such prefixes. In addition, in the description of the present embodiment, unless otherwise specified, the meaning of "multiple" is two or more.

[0059] References to "some embodiments" and the like described in this specification mean that a particular feature, structure or characteristic described in conjunction with the embodiment is included in one or more embodiments of the present application. Thus, phrases such as "in some embodiments" and the like that appear at different places in this specification do not necessarily all refer to the same embodiment, but rather mean "one or more but not all embodiments", unless otherwise specifically emphasized. The terms "include", "comprises", "has" and their variations all mean "including but not limited to", unless otherwise specifically emphasized.

[0060] When the vehicle passes through uphill and downhill sections, if the driver does not operate the accelerator pedal, the vehicle's drive system will not automatically adjust the power output of the vehicle as the road slope changes, which will cause the vehicle speed to fluctuate and affect the driver's driving experience. For example, when the vehicle passes through an uphill section, the driving force required for the vehicle to travel increases, causing the drive system to increase the driving force output to avoid a reduction in vehicle speed. For another example, when the vehicle passes through a downhill section, the driving force required for the vehicle to travel decreases, and the drive system needs to reduce the driving force output to avoid excessive speed.

[0061] Similarly, for vehicles equipped with a cruise control system (CCS), the vehicle can travel at the set target speed without the driver having to operate the accelerator pedal, thereby reducing the driver's driving fatigue. However, when the vehicle passes through uphill and downhill sections, the vehicle is also prone to such a phenomenon when entering a ramp, and it is impossible to ensure that the vehicle passes the ramp at a constant speed, affecting driving comfort.

[0062] In one solution, it is proposed to obtain the slope information of the road through the difference between the wheel deceleration and the drive motor deceleration on the vehicle control unit (VCU) side, so as to achieve the slope torque compensation of cruise control. However, the acquisition timing of the wheel speed signal and the drive motor deceleration signal is different, and the acquisition cycle of the wheel speed signal is long, and the control delay is long. In addition, complex road conditions have a large disturbance on the slope signal obtained by the vehicle, and the torque compensation effect is unstable.

[0063] Another solution is to obtain the slope information of the road through an independent slope sensor to achieve slope torque compensation. However, on the one hand, configuring a slope sensor in a vehicle will increase the complexity of vehicle control and manufacturing costs. On the other hand, the slope sensor can only accurately measure the slope information when the vehicle is static, at a constant speed or with a constant acceleration and deceleration, and cannot guarantee the accuracy of slope information measurement under complex road conditions.

[0064] In view of this, the present application provides a motor controller, a control method and an electric vehicle for realizing hill torque compensation. When the vehicle is traveling on a slope, the motor controller actively adjusts the torque output of the drive motor to realize hill torque compensation. The control delay is short, and the vehicle can realize seamless hill-crossing and improve the handling performance of the whole vehicle.

[0065] See also Figure 1 , Figure 1 This is a schematic diagram of an electric vehicle 01 provided in an embodiment of the present application. Figure 1 As shown, the electric vehicle 01 includes a drive system 10 and a power battery 30 connected to the drive system 10. The drive system 10 is used to drive the electric vehicle 01. The power battery 30 is used to provide electrical energy to the drive system 10. The drive system 10 is used to receive power from the power battery 30 and provide power to the electric vehicle 01. The drive system 10 can also be called a powertrain.

[0066] It can be understood that according to the position of the wheels in the electric vehicle 01, they can be divided into a left front wheel 41, a right front wheel 42, a left rear wheel 43, and a right rear wheel 44. According to the axle division, the left front wheel and the right front wheel are coaxial and connected by the front axle. The left rear wheel and the right rear wheel are coaxial and connected by the rear axle. According to the position division, the left front wheel and the left rear wheel are on the same side of the four wheels, located on the left side, and the right front wheel and the right rear wheel are on the same side, located on the right side. That is to say, among the four wheels of the electric vehicle 01, the left front wheel and the right front wheel are coaxial wheels with each other, and the left rear wheel and the right rear wheel are coaxial wheels with each other; the left front wheel and the left rear wheel are wheels on the same side of each other, and the right front wheel and the right rear wheel are wheels on the same side of each other.

[0067] It can be understood that the electric vehicle 01 in the embodiment of the present application can be any one of different types of vehicles such as cars, trucks, passenger buses, etc., and can also be a transportation device for carrying people or goods such as a tricycle, a two-wheeled vehicle, a train, or other types of vehicles driven by power batteries, which are not limited in the embodiment of the present application. Among them, vehicles include but are not limited to pure electric vehicles (pure electric vehicle / battery electric vehicle, pure EV / battery EV), hybrid electric vehicles (hybrid electric vehicle, HEV), range extended electric vehicles (range extended electric vehicle, REEV), plug-in hybrid electric vehicles (plug-in hybrid electric vehicle, PHEV), new energy vehicles (new energy vehicle, NEV), etc.

[0068] It is understood that the specific type of the powertrain is not limited in the embodiments of the present application. As an example and not a limitation, the powertrain can be a centralized powertrain, a hub motor powertrain, or a wheel-side motor powertrain. Among them, the hub motor powertrain is to directly set the motor and the reducer in the wheel rim, eliminating the transmission components such as the half shaft, universal joint, differential, and transmission; the wheel-side motor powertrain is to set the motor on the subframe.

[0069] It is understood that the power battery 30 in the embodiment of the present application can be a lithium-ion battery, a lithium metal battery, a lead-acid battery, a nickel-cadmium battery, a nickel-hydrogen battery, a lithium-sulfur battery, a lithium-air battery or a sodium-ion battery, etc., and the present application does not limit this. In terms of scale, the power battery 30 in the embodiment of the present application can be a single cell, or a battery module or a battery pack, and the present application does not limit this. The power battery 30 can also power other electrical devices in the vehicle, such as the air conditioner in the vehicle, the car player, etc.

[0070] Figure 2 It is a schematic diagram of the structure of the drive system 10 provided in an embodiment of the present application.

[0071] like Figure 2 As shown in (a) of the figure, the drive system 10 includes a motor 11, a motor controller 12 and a reducer (not shown in the figure), and the motor 11 is connected to two wheels of the electric vehicle 01 through the reducer. During the driving process of the electric vehicle 01, the motor controller 12 is used to control the motor 11 to output torque to drive the two wheels.

[0072] It should be noted that the embodiments of the present application do not limit the arrangement of the motors in the electric vehicle. Figure 2The drive system 10 shown in (a) may be a front driving force assembly, and the motor 11 is connected to the two front wheels of the electric vehicle 01 through the front axle transmission. For another example, Figure 2 The drive system 10 shown in (a) may also be a rear drive force assembly, and the motor 11 is connected to the two rear wheels of the electric vehicle 01 through the front axle transmission.

[0073] It can be understood that according to the position of the wheels, the four wheels can be divided into a left front wheel 41, a right front wheel 42, a left rear wheel 43, and a right rear wheel 44. According to the axle division, among the four wheels, the left front wheel 41 and the right front wheel 42 are coaxial and connected by the front axle, and the left rear wheel 43 and the right rear wheel 44 are coaxial and connected by the rear axle. According to the position division, among the four wheels of the vehicle 01, the left front wheel 41 and the right front wheel 42 are coaxial wheels, and the left rear wheel 43 and the right rear wheel 44 are coaxial wheels; the left front wheel 41 and the left rear wheel 43 are wheels on the same side, and the right front wheel 42 and the right rear wheel 44 are wheels on the same side; the left front wheel 41 and the right rear wheel 44 are diagonal wheels, and the right front wheel 42 and the left rear wheel 43 are diagonal wheels.

[0074] In the embodiment of the present application, the motor controller can control the motor to output positive torque or negative torque. Specifically, the motor 11 includes a stator winding and a rotor (not shown in the figure). The motor controller 12 can change the stator magnetic field strength and direction by adjusting the magnitude of the stator winding current and the phase of the three-phase current, thereby changing the interaction force between the stator and the rotor, that is, the motor torque.

[0075] In some embodiments, the drive system 10 also includes a rotary transformer, which can be set on the motor 11 (for example, on the rotor of the motor) to accurately detect the position, direction and speed of the motor rotor, and is responsible for monitoring and extracting the motor rotation speed. It has a high sampling rate and is directly communicated with the motor controller with a short communication link.

[0076] like Figure 2 As shown in (b), the drive system 10 includes a motor controller 12 and two motors. Among them, the two motors include motor 11 and motor 13. At this time, one axle of the electric vehicle 01 includes two half-axles that are decoupled from each other, the motor 11 is connected to a wheel of the electric vehicle 01 through a half-axle transmission, and the motor 13 is connected to another wheel coaxial with the one wheel through another half-axle transmission. During the driving process of the electric vehicle 01, the motor controller 12 is used to control the motor 11 to output torque to drive the one wheel, and control the motor 13 to output torque to drive the other wheel. Exemplarily, the drive system 10 is a front-wheel drive assembly, in which case the one wheel is the left front wheel 41, and the other wheel is the right front wheel 42.

[0077] It is understood that in other embodiments of the present application, the drive system 10 may also include two motor controllers and two motors. During the driving process of the electric vehicle 01, one motor controller is used to control one motor to drive one wheel, and the other motor controller is used to control another motor to drive another wheel coaxial with the one wheel.

[0078] It is understood that in other embodiments of the present application, the electric vehicle 01 may also include two or more power assemblies, and the structures of the power assemblies may be the same or different. For example, the electric vehicle 01 may include a front driving force assembly and a rear driving force assembly, wherein the structure of the front driving force assembly is as follows: Figure 2 As shown in (a) of FIG. 1 , the structure of the rear drive force assembly is as follows: Figure 2 As shown in (b) of FIG. 1 , the overall drive system of the electric vehicle 01 presents a three-motor architecture with a single front motor and a double rear motor. For another example, the electric vehicle 01 may include a front driving force assembly and a rear driving force assembly, wherein the structures of the front driving force assembly and the rear driving force assembly are as shown in FIG. Figure 2 As shown in (b) in the figure, at this time, the driving system of the electric vehicle 01 as a whole presents a four-motor architecture with two motors at the front and two at the rear.

[0079] Continue to refer Figure 1 The electric vehicle 01 also includes a controller 20, which is used to control the operation of the electric vehicle 01 during the driving process of the electric vehicle 01. Among them, in the electric vehicle 01, the driver can change the driving state of the vehicle by adjusting the opening of the accelerator pedal and the brake pedal. Specifically, the controller can detect the opening of the accelerator pedal and the brake pedal. When it is detected that the opening of any pedal changes, the controller controls the motor to adjust the torque output through the motor controller, thereby changing the driving force of the wheel, so that the vehicle can travel according to the driver's needs. Alternatively, when it is detected that the opening of the brake pedal changes, the controller controls the vehicle's braking system to adjust the braking torque, thereby changing the braking force on the wheel, so that the vehicle can travel according to the driver's needs.

[0080] In some embodiments, the controller 20 may be a controller cluster composed of multiple controllers. For example, the controller cluster includes but is not limited to a chassis controller, a vehicle controller (VCU, Vehicle Control Unit) and a central controller in a braking system. The chassis controller, the central controller, the vehicle controller and the motor controller in the powertrain can communicate with each other through a CAN network. Among them, the chassis controller is used to obtain the information collected by the above-mentioned sensors or other acquisition devices, and perform corresponding data processing to output the requested torque; the vehicle controller is used to receive the requested torque output by the chassis controller and other components (such as an accelerator pedal, a brake pedal, etc.), and arbitrate to determine the target torque that the drive motor ultimately needs to output, and send it to the motor controller in the form of a signal; the motor controller is used to send a corresponding torque control signal to the motor to control the motor to output the target torque.

[0081] It should be noted that the controller 20 may also include other types of controllers or combinations thereof, and perform the above functions through these controllers; alternatively, the functions of the above controllers may also be mutually adjusted according to actual needs, which is not limited in the embodiments of the present application.

[0082] In other embodiments, the controller 20 can be a single controller, which can be integrated into any one of the vehicle controller, chassis controller or central controller, or can be a separate controller to output corresponding signals for the vehicle controller to perform driving torque control and for the central controller to perform braking torque control.

[0083] The architecture of the embodiment of the present application is introduced above. The specific manner in which the motor controller implements ramp torque compensation is described below in combination with a specific embodiment, taking the motor controller 12 as an example.

[0084] In some embodiments, the motor controller 12 is used to control a drive motor 11 to output torque to drive the wheels of the electric vehicle 01. When the electric vehicle 01 is traveling on a road with a slope less than or equal to a preset slope threshold, the drive motor 11 is controlled to output the torque indicated by the torque signal. When the electric vehicle 01 is traveling on a slope with a slope greater than a preset slope threshold, the motor controller 12 is specifically used to actively control a drive motor 11 to adjust the torque output.

[0085] It can be understood that the motor controller 12 provided in the embodiment of the present application can independently perform ramp torque compensation. When it is detected that the electric vehicle 01 is traveling on a slope with a slope greater than the slope thereof, it can be controlled not according to the indication of the torque signal, but the torque to be output can be adjusted to directly perform torque compensation. When the vehicle passes through a ramp, the torque output by the drive motor is determined by the motor controller and does not change with the torque change indicated by the torque signal, that is, the motor controller 12 controls the torque output by the motor to be greater than or less than the torque indicated by the torque signal, which can shorten the control path and effectively reduce the control time of torque compensation.

[0086] It can be understood that the motor controller 12 can be connected to the slope sensor in the vehicle for communication, and obtain the slope of the current road surface through the slope sensor, or the motor controller 12 can also obtain the speed of the drive motor 11 according to the motor speed signal provided by the resolver sensor to determine the slope of the current road surface, and then actively control the drive motor 11 to adjust the torque output when the vehicle enters a slope with a slope greater than a preset slope threshold. The specific manner in which the motor controller 12 determines the speed of the drive motor 11 according to the motor speed signal will be described in detail later, and will not be repeated here.

[0087] It is understood that different modes of the electric vehicle 01 may correspond to different preset slope thresholds. For example, the preset slope threshold corresponding to the comfort mode may be smaller than the preset slope threshold corresponding to the sports mode. It is understood that the embodiment of the present application can further improve the user experience by setting differentiated preset slope thresholds.

[0088] According to the embodiment of the present application, when the electric vehicle is driving on a slope, even if the driver does not actively adjust the opening of the accelerator pedal, the motor controller can actively control the drive motor to adjust the torque output to achieve slope torque compensation without the instruction of the vehicle controller, thereby maintaining the speed of the electric vehicle when passing through the slope, achieving non-sensing slope crossing, and further improving driving comfort. In addition, the slope torque compensation control can be closed-loop inside the motor controller, with a short control path and high real-time control.

[0089] In some embodiments, when the electric vehicle 01 is traveling uphill on a slope, the motor controller 12 is specifically used to actively control a drive motor 11 to increase the torque output. When the electric vehicle 01 is traveling downhill on a slope, the motor controller 12 is specifically used to actively control a drive motor 11 to reduce the torque output.

[0090] It can be understood that when the electric vehicle 01 travels from the road to the uphill section, the driving force required for the vehicle to move forward increases under the action of inertia. If the motor controller 12 still controls the motor 11 to output torque according to the instruction of the torque signal, the power of the whole vehicle will be insufficient to maintain the vehicle at a constant speed uphill, and the driver will noticeably feel that the vehicle speed has dropped, which does not meet the driver's expectations. Therefore, the motor controller 12 needs to actively control the motor 11 to increase the torque output so that the vehicle speed remains stable when traveling on the road and the slope.

[0091] It can be understood that when the electric vehicle 01 travels from the road to the downhill section, the driving force required for the vehicle to move forward is reduced due to the action of inertia. If the motor controller 12 still controls the motor 11 to output torque according to the indication of the torque signal, the power of the whole vehicle will be insufficient to keep the vehicle going downhill at a constant speed. The driver will feel that the vehicle is accelerating downhill, which does not meet the driver's expectations. Moreover, if the driver does not actively intervene at this time, the excessive speed may affect driving safety. Therefore, the motor controller 12 needs to actively control the motor 11 to reduce the torque output so that the speed of the vehicle remains stable when driving on the road and slope.

[0092] According to the embodiment of the present application, the motor controller will specifically control the drive motor to adjust the torque output when the vehicle is going uphill or downhill, so that the power of the entire vehicle can ensure the stability of the vehicle speed, with simple control method and strong reliability.

[0093] In some embodiments, when the electric vehicle 01 is traveling uphill on a slope, the motor controller 12 is specifically used to actively control a drive motor 11 to increase the torque output so that the torque output by the drive motor 11 is greater than the torque indicated by the torque signal. When the electric vehicle 01 is traveling downhill on a slope, the motor controller 12 is specifically used to actively control a drive motor 11 to reduce the torque output so that the torque output by the drive motor 11 is less than the torque indicated by the torque signal.

[0094] Among them, the torque signal can be generated by the vehicle controller based on the cruise control speed set by the driver, or it can be generated by the vehicle controller based on the opening of the accelerator pedal operated by the driver. It can be understood that when the vehicle is driving on a slope, due to the decoupling of the operation of the motor controller 12 and the vehicle controller, the torque output by the motor controller 12 to control the drive motor 11 and the torque indicated by the torque signal will be different. At this time, the vehicle controller is actually not controlling the torque of the motor controller 12. Therefore, in one embodiment, the torque indicated by the torque signal output by the vehicle controller remains unchanged.

[0095] In these embodiments, when the electric vehicle 01 is traveling uphill, the motor controller 12 will actively control the drive motor 11 to increase the torque output so that the torque actually output by the drive motor 11 is greater than the torque indicated by the torque signal. When the electric vehicle 01 is traveling downhill, the motor controller 12 will actively control the drive motor 11 to reduce the torque output so that the torque actually output by the drive motor 11 is less than the torque indicated by the torque signal.

[0096] like Figure 3 As shown in the solid line part in , from time t0 to time t1, the electric vehicle 01 is traveling on a road with a slope less than a preset slope threshold. At this time, the motor controller 12 controls the drive motor 11 to output the torque T1 indicated by the torque signal, and the speed of the electric vehicle 01 is V1. From time t1 to time t2, the electric vehicle 01 is traveling uphill on a slope with a slope greater than the preset slope threshold. At this time, in order to stabilize the speed of the electric vehicle 01 at V1, the motor controller 12 actively controls the torque output by the drive motor 11 to increase to T2, so that the torque actually output by the drive motor 11 is greater than the torque T1 indicated by the torque signal.

[0097] like Figure 3 As shown in the dashed part in , from time t0 to time t1, the electric vehicle 01 is traveling on a road with a slope less than a preset slope threshold, at which time the torque output by the drive motor 11 is T1, and the speed of the electric vehicle 01 is V1. From time t1 to time t2, the electric vehicle 01 is traveling downhill on a slope with a slope greater than a preset slope threshold, at which time, in order to stabilize the speed of the electric vehicle 01 at V1, the motor controller 12 actively controls the torque output by the drive motor 11 to be reduced to T3, so that the torque actually output by the drive motor 11 is less than the torque T1 indicated by the torque signal.

[0098] According to the embodiment of the present application, when the vehicle is driving on a slope, the operation of the motor controller is decoupled from the vehicle controller, and the torque output by the drive motor can be actively controlled to be greater than or less than the torque indicated by the torque signal, without waiting for the vehicle controller to send a torque signal again to adjust the torque output of the drive motor, and the control is more timely. In addition, the ramp torque compensation function of the motor controller can be used in both the vehicle automatic driving scenario and the driver manual driving scenario, and is highly practical.

[0099] In some embodiments, in the process of actively controlling a drive motor 11 to adjust the torque output, the motor controller 12 is specifically used to control a drive motor 11 to output the torque indicated by a torque signal in response to a change in the opening of an accelerator pedal of the electric vehicle 01 being greater than a preset change value.

[0100] It can be understood that the change in the opening of the accelerator pedal of the electric vehicle 01 is greater than the preset change value, which can be understood as the driver's expectation to adjust the driving speed of the electric vehicle 01 by operating the opening of the accelerator pedal. At this time, the vehicle controller will generate an adjusted torque signal according to the adjusted opening of the accelerator pedal. Furthermore, if the adjusted torque signal is received during the process of actively controlling the drive motor 11 to adjust the torque output, the motor controller 12 will interrupt the ramp torque compensation function and control the drive motor 11 to output torque according to the adjusted torque signal, so that the power output of the vehicle is more in line with the driver's expectations.

[0101] It is easy to understand that when the increase in the opening of the accelerator pedal is greater than the preset change value, the motor controller 12 will control the drive motor 11 to increase the torque output according to the indication of the torque signal. When the decrease in the opening of the accelerator pedal is greater than the preset change value, the motor controller 12 will control the drive motor 11 to reduce the torque output according to the indication of the torque signal.

[0102] According to an embodiment of the present application, during the process of the motor controller performing slope torque compensation, the motor controller will also adjust the torque output by the drive motor according to the indication of the torque signal when the accelerator pedal operated by the driver is opened, so that the power output of the entire vehicle is more in line with the driver's expectations, further improving the controllability of the electric vehicle.

[0103] In some embodiments, when the electric vehicle 01 is driving on a slope, the motor controller 12 responds to the torque indicated by the torque signal remaining unchanged or the opening of the accelerator pedal remaining unchanged, and the speed of a drive motor 11 indicated by the rotary transformer signal changes by a magnitude greater than a preset magnitude within a preset time period. The motor controller 12 is specifically used to actively control a drive motor 11 to adjust the torque output.

[0104] It can be understood that since the torque indicated by the torque signal remains unchanged or the opening of the accelerator pedal remains unchanged, the situation where the driver actively controls the electric vehicle 01 to accelerate or decelerate can be ruled out, avoiding misjudgment.

[0105] It can be understood that the preset amplitude can be a smaller speed value, which can ensure that when the motor controller 12 recognizes that the speed change value of the drive motor 11 within the preset time is greater than the preset amplitude to perform active torque adjustment, the driver is basically unaware of the speed change of the electric vehicle 01. For example, the preset amplitude can be 100 revolutions per second (rpm), and the speed change of the drive motor 11 by 100 rpm is actually reflected in the speed change of the electric vehicle 01 by only 1 kilometer per hour (kilometer / hour, km / h), which the driver is basically unaware of. In other words, there is no need to set up an additional ramp sensor in the electric vehicle 01, and the motor controller 12 can independently perform ramp detection based on the rotary signal, which can effectively reduce the complexity of communication and shorten the time it takes for the motor controller to obtain ramp information.

[0106] For example, when the torque indicated by the torque signal remains unchanged or the opening of the accelerator pedal remains unchanged, and the speed of the drive motor 11 indicated by the resolver signal decreases by 100 rpm within a preset range, the motor controller 12 determines that the electric vehicle 01 is currently in an uphill state, and it is necessary to actively control the drive motor 11 to increase the torque output.

[0107] For example, when the torque indicated by the torque signal remains unchanged or the opening of the accelerator pedal remains unchanged, and the speed of the drive motor 11 indicated by the resolver signal increases by 100 rpm within a preset range, the motor controller 12 determines that the electric vehicle 01 is currently in a downhill state, and it is necessary to actively control the drive motor 11 to reduce the torque output.

[0108] It can be understood that the motor controller 12 can collect the resolver acceleration obtained by the real-time resolver signal when it is recognized that the speed change value of the drive motor 11 within the preset time is greater than the preset amplitude, and filter the resolver acceleration signal and adjust the filter parameters to remove burrs, so that the resolver acceleration signal approaches the vehicle acceleration. Furthermore, the motor controller 12 will determine the ramp information according to the resolver acceleration signal and the real-time torque signal of the drive motor 11 according to the longitudinal dynamics, and then perform ramp torque compensation based on the torque indicated by the torque signal.

[0109] It can be understood that due to the complex driving conditions of the vehicle, various signals in the vehicle, such as the resolver signal and the actual torque of the motor, will cause jitter, resulting in severe distortion of the ramp information. In the process of calculating the ramp information, the vehicle power acceleration is calculated based on the ramp information identified at the previous moment, and compared with the vehicle acceleration obtained after the actual resolver filtering at the current moment. If the difference between the two is less than the preset acceleration threshold, the ramp torque compensation is performed based on the vehicle acceleration calculated at the previous moment. If the difference between the two is greater than the preset acceleration threshold, the ramp torque compensation is performed based on the vehicle acceleration calculated at the current moment.

[0110] In the embodiment of the present application, the motor controller 12 can use a Sigma-Delta Analog-to-Digital Converter (SDADC) to sample the resolver signal, and its sampling rate can reach 2Mhz, and its sampling accuracy can reach 16bit, and the acquired sampling parameters are reliable. In other words, there is no need to set up an additional ramp sensor in the electric vehicle 01. The motor controller 12 can use SDADC to effectively improve the sampling speed and accuracy of the motor speed of the sampling drive motor 11, thereby enhancing the real-time and accuracy of the motor controller 12 in performing ramp torque compensation.

[0111] According to the embodiment of the present application, the motor controller can perform ramp detection according to the rotation speed of the drive motor and control the drive motor to perform ramp torque compensation, thereby realizing the closed loop of the entire control process inside the motor controller, with high control bandwidth and small fluctuation. In addition, the motor controller can sample the resolver signal through SDADC to determine the ramp information, and the real-time and precision of the ramp information detection are higher, further enhancing the stability of the ramp torque compensation.

[0112] In some embodiments, during the process of the motor controller 12 actively controlling a drive motor 11 to adjust the torque output, in response to the slip rate of a wheel driven by a drive motor 11 being greater than a preset slip rate, the motor controller 12 is further used to control the drive motor 11 to reduce the torque output. During the process of the motor controller 12 actively controlling a drive motor 11 to adjust the torque output, in response to the slip rate of a wheel driven by a drive motor 11 being less than a preset slip rate, the motor controller 12 is further used to control the drive motor 11 to increase the torque output. Figure 4 As shown, the dotted line represents the preset slip ratio, and the solid line represents the actual slip ratio. When the slip ratio deviates from the preset slip ratio, the torque output by the driving motor also changes accordingly.

[0113] Among them, the slip rate of the wheel can be understood as the proportion of the sliding component of the wheel during movement. When the adhesion of the road surface changes, the slip rate of the wheel will also change accordingly. A slip rate that is too high will cause the wheel to rotate but fail to effectively transmit driving force or braking force. A slip rate that is too low will cause the driving force or braking force transmitted by the wheel to be greater than expected, thereby affecting the steering ability and stability of the vehicle. Therefore, during the driving or steering process of the electric vehicle 01, the slip rate of the wheel needs to be controlled near the preset slip rate.

[0114] It can be understood that the wheel slip phenomenon may be caused by a sudden change in the road adhesion coefficient, for example, when the electric vehicle 01 travels from a paved cement road to an icy road, the wheel speed may suddenly increase. Alternatively, the wheel slip phenomenon may also be caused by the electric vehicle 01 passing through a bump on an uneven road surface, for example, when the wheel of the electric vehicle 01 passes over a pothole on the road surface, the wheel may spin idly, causing the wheel speed to suddenly increase. For another example, when the wheel of the electric vehicle 01 passes over a bump on the road surface, the wheel rotation may be blocked, causing the wheel speed to suddenly decrease.

[0115] In the embodiment of the present application, the motor controller 12 can also calculate the slip rate of the wheel driven by the drive motor 11 according to the rotation speed of the drive motor 11 and the output torque of the drive motor in the process of actively controlling the drive motor 11 to adjust the torque output, and further control the drive motor corresponding to the wheel to adjust the torque output, so as to ensure the driving stability of the vehicle. Exemplarily, when the slip rate of the left front wheel 41 is greater than the preset slip rate, the motor controller 12 can control the drive motor 11 to reduce the torque output so that the slip rate of the left front wheel 41 is reduced to the preset slip rate, thereby avoiding the driving force or braking force transmitted by the left front wheel 41 to be too small and causing the body of the electric vehicle to deviate. When the slip rate of the left front wheel 41 is less than the preset slip rate, the motor controller 12 can control the drive motor 11 to increase the torque output so that the slip rate of the left front wheel 41 is increased to the preset slip rate, thereby avoiding the driving force or braking force transmitted by the left front wheel 41 to be too large and causing the body of the electric vehicle to deviate.

[0116] According to an embodiment of the present application, the motor controller can determine the slip rate of the wheel by driving the rotational speed and output torque of the motor. In this way, the observation of whether the wheel is slipping and the adjustment of the slip rate of the wheel are both implemented inside the drive system, with shorter time delay, and can almost achieve microsecond (us) level rapid observation and millisecond (ms) level torque adjustment.

[0117] In some embodiments, one drive motor is used to drive the two front wheels of the electric vehicle, and the electric vehicle 01 also includes another drive motor for driving the two rear wheels of the electric vehicle. When the electric vehicle 01 is traveling uphill on a slope, the motor controller is used to control the increase in the torque output of one drive motor to be less than the increase in the torque output of another drive motor. When the electric vehicle is traveling downhill on a slope, the motor controller is used to control the decrease in the torque output of one drive motor to be greater than the decrease in the torque output of another drive motor.

[0118] It can be understood that for an electric vehicle with front and rear dual electric drive, when the electric vehicle 01 is driving uphill on a slope, controlling the rear wheel load to be larger can more fully exert the driving force. At this time, the torque value increased by the drive motor controlled by another motor controller to drive the two rear wheels is greater than the torque value increased by the drive motor controlled by the motor controller to drive the two front wheels.

[0119] For example, Figure 5 As shown in (a), from time t0 to time t1, the electric vehicle 01 is traveling on the road. At this time, the torque output by the front drive motor is T1, and the torque output by the rear drive motor is T2. T1 and T2 can be equal or unequal. The vehicle controller can distribute the torque according to the specific implementation without restriction. From time t1 to time t2, the electric vehicle 01 is traveling uphill on a slope. The torque output by the front drive motor increases by △T1, and the torque output by the rear drive motor increases by △T2, and △T2 is greater than △T1. Among them, △T1 can be zero, that is, when the electric vehicle 01 is traveling uphill on a slope, only the rear drive power assembly can actively perform slope torque compensation, and the front drive power assembly can output torque according to the indication of the torque signal.

[0120] It can be understood that for an electric vehicle with front and rear dual electric drive, when the electric vehicle 01 is driving downhill on a slope, controlling the front wheel load to be larger can more fully exert the driving force. At this time, the torque value reduced by the motor controller controlling the drive motor used to drive the two front wheels is greater than the torque value reduced by the other motor controller controlling the drive motor used to drive the two rear wheels.

[0121] For example, Figure 5 As shown in (b), from time t0 to time t1, the electric vehicle 01 is traveling on the road, at which time the torque output by the front drive motor is T3, and the torque output by the rear drive motor is T4. T3 and T4 may be equal or unequal, and this application does not limit this. From time t1 to time t2, the electric vehicle 01 is traveling downhill on a slope, the torque output by the front drive motor decreases by △T3, and the torque output by the rear drive motor decreases by △T4, and △T3 is greater than △T4. Among them, △T3 can be zero, that is, when the electric vehicle 01 is traveling downhill on a slope, only the front drive power assembly can actively perform slope torque compensation, and the rear drive power assembly can output torque according to the indication of the torque signal.

[0122] According to the embodiments of the present application, for electric vehicles with front and rear dual electric drives, the front drive motor and the rear drive motor can be controlled to differentially adjust the torque output values ​​when the vehicle is going uphill and downhill, so that the entire vehicle can more fully exert the driving force, thereby more accurately achieving the vehicle's senseless slope crossing and further improving driving comfort.

[0123] In some embodiments, a drive motor 11 is used to drive a left wheel of the electric vehicle 01, and the electric vehicle also includes another drive motor 13 for driving a right wheel coaxial with one wheel. During the process of the electric vehicle 01 driving uphill on a slope, in response to the angle of the steering wheel of the electric vehicle 01 turning to the left being greater than the preset angle threshold, the motor controller 12 is specifically used to control the increase in the torque output of another drive motor 13 to be greater than the increase in the torque output of one drive motor 11. In response to the angle of the steering wheel of the electric vehicle 01 turning to the right being greater than the preset angle threshold, the motor controller 12 is specifically used to control the increase in the torque output of one drive motor 11 to be greater than the increase in the torque output of another drive motor 13.

[0124] It can be understood that the preset turning angle threshold can be understood as a smaller turning angle, and the turning angle of the steering wheel of the electric vehicle 01 greater than the preset turning angle threshold can be understood as the driver's desire to control the vehicle steering by operating the steering wheel. For the scenario of the electric vehicle turning uphill, in the powertrain of the dual-motor architecture, the motor controller 12 will determine the speed of the motor corresponding to the left wheel and the speed of the motor corresponding to the right wheel according to the resolver signal, and distribute the torque according to the speed of the motors on both sides, so that the actual yaw moment of the whole vehicle is better close to the expected yaw moment, ensuring lateral stability and improving steering performance.

[0125] For example, when the electric vehicle 01 turns uphill, the left motor allocation coefficient = left rotary speed / (left rotary speed + right rotary speed), the right motor allocation coefficient = right rotary speed / (left rotary speed + right rotary speed), that is, the actual motor compensation torque = motor allocation coefficient * total compensation torque. Figure 6 As shown, since the rotation speed of the right motor is higher when the electric vehicle turns left, the motor controller 12 controls the torque increase value of the right motor to be greater than the torque increase value of the left motor. Similarly, since the rotation speed of the left motor is higher when the electric vehicle turns right, the motor controller 12 controls the torque increase value of the left motor to be greater than the torque increase value of the right motor.

[0126] Similarly, during the vehicle's downhill driving, in response to the electric vehicle 01 steering wheel turning to the left at an angle greater than a preset angle threshold, the motor controller 12 is specifically used to control the reduction value of the torque output of another drive motor 13 to be greater than the reduction value of the torque output of one drive motor 11. In response to the electric vehicle 01 steering wheel turning to the right at an angle greater than a preset angle threshold, the motor controller 12 is specifically used to control the reduction value of the torque output of one drive motor 11 to be greater than the reduction value of the torque output of another drive motor 13.

[0127] According to an embodiment of the present application, for an electric vehicle with a dual-motor architecture powertrain, when the vehicle turns on a slope, the motor controller can control the torque value adjusted by the drive motor used to drive the wheels turning to the outside to be greater than the torque value adjusted by the drive motor used to drive the wheels turning to the inside, thereby ensuring the lateral stability of the vehicle during the turning process and further improving the vehicle's controllability.

[0128] In some embodiments, after the motor controller 12 controls the drive motor 11 to adjust the torque output, the motor controller 12 is also used to output an adjusted torque signal, which is used to indicate the torque actually output by the drive motor 11, or the adjusted torque signal is used to indicate the slope compensation torque.

[0129] According to an embodiment of the present application, the motor controller can send the current working status of the motor to the vehicle controller after controlling the drive motor to perform ramp torque compensation. There is no need for the vehicle controller to send a torque adjustment strategy a second time, thereby achieving a closed loop for the entire control process within the motor controller, shortening the control path, and improving the control speed and accuracy.

[0130] For ease of understanding, the following Figure 7 The scheme provided in the embodiment of the present application is illustrated by way of example. Figure 7 A schematic flow chart of a ramp torque compensation method provided in an embodiment of the present application is shown. The method can be applied to a motor controller. The method includes S701 to S704.

[0131] S701: Signal input. In the embodiment of the present application, the signal input includes at least a torque signal or an opening of the accelerator pedal, and a resolver signal. It is understood that when the user enables the cruise control function, the signal output may also include an enable signal of the cruise control function.

[0132] S702: Determine whether ramp torque compensation is required. After receiving the aforementioned input signal, the motor controller determines whether the electric vehicle is traveling on a ramp with a slope greater than a preset slope threshold, and then determines whether the electric vehicle needs ramp torque compensation. If yes, the subsequent step S703 is executed; otherwise, the drive motor is controlled to output the torque indicated by the torque signal.

[0133] S703: Calculate the ramp compensation torque of the drive motor. Exemplarily, after determining that ramp torque compensation is required, the motor controller can calculate the torque value that the drive motor needs to adjust based on the resolver speed and resolver acceleration indicated by the resolver signal and the actual output torque of the drive motor.

[0134] S704: Control and adjust the output torque of the drive motor. Exemplarily, based on the output torque of the drive motor calculated in step S703, the drive motor is controlled to drive the corresponding wheels, so that the electric vehicle 01 can achieve non-sensing hill-crossing.

[0135] In the embodiment of the present application, the electric vehicle 01 can be a four-motor driven electric vehicle, a three-motor driven electric vehicle or a two-motor driven electric vehicle. Exemplarily, when the electric vehicle 01 is a four-motor driven electric vehicle, the electric vehicle 01 includes four motor controllers and four drive motors, and the four motor controllers are used to control the four drive motors respectively, and each of the four drive motors can drive one wheel of the electric vehicle 01 respectively. When the electric vehicle 01 is a three-motor driven electric vehicle, the electric vehicle 01 includes three motor controls and three drive motors, and the three motor controllers are used to control the three drive motors respectively, and two of the three drive motors are used to drive two coaxial wheels respectively, and another of the three drive motors is used to drive the other two coaxial wheels at the same time. When the electric vehicle 01 is a two-motor driven electric vehicle, the electric vehicle 01 includes two motor controls and two drive motors, and the two motor controllers are used to control the two drive motors respectively, and each drive motor is used to drive two front wheels or two rear wheels respectively. Furthermore, when the drive motor is used to drive one of the wheels of the electric vehicle 01, the slip rate described above may be the slip rate of the one wheel; when the drive motor is used to drive two coaxial wheels of the electric vehicle 01, the slip rate described above may be the slip rate of the two coaxial wheels.

[0136] The motor controller provided in the embodiment of the present application can be any one of the motor controllers in the above-mentioned four-motor driven electric vehicle, or any one of the motor controllers in the above-mentioned three-motor driven electric vehicle, or any one of the motor controllers in the above-mentioned two-motor driven electric vehicle, and the embodiment of the present application does not make specific limitations on this.

[0137] The embodiment of the present application also provides a vehicle control method, which is used to control the drive system 10 of the electric vehicle 01 to adjust the torque output to achieve slope torque compensation when the electric vehicle 01 is running on a slope. The vehicle control method includes: at a first moment, in response to the electric vehicle 01 running on a road with a slope less than or equal to a preset slope threshold, controlling the drive system 10 to output torque to drive the wheels of the electric vehicle 01. At a second moment after the first moment, in response to the electric vehicle 01 running on a slope with a slope greater than the preset slope threshold and the opening of the accelerator pedal of the electric vehicle 01 remains unchanged, controlling the drive system to adjust the torque output.

[0138] In some embodiments, the control method also includes: at a second moment, in response to the electric vehicle 01 driving on a slope with a slope greater than a preset slope threshold, the opening of the accelerator pedal of the electric vehicle remains unchanged and the electric vehicle is running in a forward gear, controlling the drive system to adjust the torque output.

[0139] It should be emphasized that in these embodiments, the drive system 10 is controlled to perform slope torque compensation only when the vehicle is running in forward gear and passing through a slope. In other words, when the electric vehicle is running in reverse gear and passing through a slope, the vehicle control method will control the drive system 10 to output torque according to the indication of the torque signal, thereby ensuring that the driver can perceive the slope of the road through the vehicle speed change, thereby improving driving safety.

[0140] In some embodiments, the vehicle control method further includes: controlling the drive system to increase or decrease the torque output at the second moment so that the torque output by the drive system is not equal to the torque indicated by the torque signal.

[0141] In some embodiments, the vehicle control method further includes: when the electric vehicle 01 is traveling uphill on a slope, the increase in the torque output of the drive system 10 to the two front wheels of the electric vehicle 01 is controlled to be smaller than the increase in the torque output of the drive system 10 to the two rear wheels of the electric vehicle 01. When the electric vehicle 01 is traveling downhill on a slope, the decrease in the torque output of the drive system 10 to the two rear wheels of the electric vehicle 01 is controlled to be smaller than the decrease in the torque output of the drive system 10 to the two front wheels of the electric vehicle 01.

[0142] In some embodiments, the vehicle control method further includes: when the electric vehicle 01 is traveling uphill on a slope, in response to the steering wheel of the electric vehicle 01 turning left at an angle greater than a preset angle threshold, the increase in the torque output of the drive system 10 to the left wheel is actively controlled to be smaller than the increase in the torque output of the drive system 10 to the right wheel. When the electric vehicle 01 is traveling uphill on a slope, in response to the steering wheel of the electric vehicle 01 turning right at an angle greater than a preset angle threshold, the increase in the torque output of the drive system 10 to the right wheel is actively controlled to be smaller than the increase in the torque output of the drive system 10 to the left wheel.

[0143] In some embodiments, the vehicle control method also includes: at a third moment after the second moment, in response to the electric vehicle 01 being driven on a slope with a slope greater than a preset slope threshold and the change in the opening of the accelerator pedal of the electric vehicle 01 is greater than a preset change value, controlling the drive system 10 to output the torque indicated by the torque signal.

[0144] It should be noted that the controller 20 provided in the embodiment of the present application can be used to execute the vehicle control method in the above embodiment.

[0145] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art who is familiar with the present technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

Claims

1. A motor controller for realizing ramp torque compensation, characterized in that: The motor controller is used to control a drive motor to output torque to drive the wheels of the electric vehicle; The motor controller is specifically used for: When the electric vehicle is traveling on a road with a slope less than or equal to a preset slope threshold, the one driving motor is controlled to output a torque indicated by a torque signal; When the electric vehicle is traveling on a slope with a slope greater than a preset slope threshold, the electric vehicle actively controls the one driving motor to adjust the torque output.

2. The motor controller according to claim 1, characterized in that: The motor controller is specifically used for: During the process of the electric vehicle traveling uphill on the slope, the one driving motor is actively controlled to increase the torque output; During the process of the electric vehicle traveling downhill on the slope, the one driving motor is actively controlled to reduce the torque output.

3. The motor controller according to claim 1, characterized in that: The motor controller is specifically used for: During the process of the electric vehicle traveling uphill on the slope, the electric vehicle actively controls the one driving motor to increase the torque output so that the torque output by the one driving motor is greater than the torque indicated by the torque signal; During the process of the electric vehicle traveling downhill on the slope, the one driving motor is actively controlled to reduce the torque output so that the torque output by the one driving motor is less than the torque indicated by the torque signal.

4. The motor controller according to claim 1, characterized in that: The motor controller is specifically used for: In the process of actively controlling the one drive motor to adjust the torque output, in response to a change in the opening of the accelerator pedal of the electric vehicle being greater than a preset change value, the one drive motor is controlled to output the torque indicated by the torque signal.

5. The motor controller according to claim 1, characterized in that: The motor controller is specifically used for: During the driving of the electric vehicle on the slope, in response to the torque indicated by the torque signal remaining unchanged or the opening of the accelerator pedal remaining unchanged, and the rotation speed of the one drive motor indicated by the resolver signal changing by a value greater than a preset value within a preset time period, the one drive motor is actively controlled to adjust the torque output.

6. The motor controller according to any one of claims 1 to 5, characterized in that: The motor controller is also used for: In the process of actively controlling the one driving motor to adjust the torque output, in response to a slip ratio of a wheel driven by the one driving motor being greater than a preset slip ratio, controlling the one driving motor to reduce the torque output; In the process of actively controlling the one driving motor to adjust the torque output, in response to a slip ratio of a wheel driven by the one driving motor being less than a preset slip ratio, the one driving motor is controlled to increase the torque output.

7. The motor controller according to any one of claims 1 to 6, characterized in that: The one driving motor is used to drive the two front wheels of the electric vehicle, and the electric vehicle also includes another driving motor for driving the two rear wheels of the electric vehicle; The motor controller is used to: During the process of the electric vehicle traveling uphill on the slope, the increase value of the torque output of the one driving motor is controlled to be smaller than the increase value of the torque output of the other driving motor; During the process of the electric vehicle traveling downhill on the slope, the reduction value of the torque output of the one driving motor is controlled to be greater than the reduction value of the torque output of the other driving motor.

8. The motor controller according to any one of claims 1 to 7, characterized in that: The one driving motor is used to drive a left wheel of the electric vehicle, and the electric vehicle further comprises another driving motor for driving a right wheel coaxial with the one left wheel; During the process of the electric vehicle traveling uphill on the slope, the motor controller is used to: In response to the steering wheel of the electric vehicle turning left at an angle greater than a preset angle threshold, controlling the increase value of the torque output of the further drive motor to be greater than the increase value of the torque output of the one drive motor; In response to the steering wheel of the electric vehicle turning right at an angle greater than a preset angle threshold, the increase value of the torque output of the one driving motor is controlled to be greater than the increase value of the torque output of the other driving motor.

9. A control method for an electric vehicle, characterized in that: The control method is used to control the driving system of the electric vehicle to adjust the torque output when the electric vehicle is traveling on a slope to achieve slope torque compensation, and the control method includes: At a first moment, in response to the electric vehicle traveling on a road with a slope less than or equal to a preset slope threshold, controlling the drive system to output torque to drive the wheels of the electric vehicle; At a second moment after the first moment, in response to the electric vehicle traveling on a slope having a slope greater than a preset slope threshold and the opening of the accelerator pedal of the electric vehicle remaining unchanged, the drive system is controlled to adjust the torque output.

10. The control method according to claim 9, characterized in that: The control method further comprises: At the second moment, in response to the electric vehicle traveling on a slope having a slope greater than a preset slope threshold, the opening of the accelerator pedal of the electric vehicle remaining unchanged and the electric vehicle running in a forward gear, the drive system is controlled to adjust the torque output.

11. The control method according to claim 10 or 11, characterized in that: The control method comprises: At the second moment, the driving system is controlled to increase or decrease the torque output, so that the torque output by the driving system is not equal to the torque indicated by the torque signal.

12. The control method according to any one of claims 9 to 11, characterized in that: The control method further comprises: During the process of the electric vehicle traveling uphill on the slope, the increase value of the torque output by the drive system to the two front wheels of the electric vehicle is controlled to be smaller than the increase value of the torque output by the drive system to the two rear wheels of the electric vehicle; During the process of the electric vehicle traveling downhill on the slope, the reduction value of the torque output by the drive system to the two rear wheels of the electric vehicle is controlled to be smaller than the reduction value of the torque output by the drive system to the two front wheels of the electric vehicle.

13. The control method according to any one of claims 9 to 12, characterized in that: The control method further comprises: During the process of the electric vehicle traveling uphill on the slope, in response to the steering wheel of the electric vehicle turning left at an angle greater than a preset angle threshold, the increase in the torque output of the drive system to the left wheel is actively controlled to be smaller than the increase in the torque output of the drive system to the right wheel; During the process of the electric vehicle traveling uphill on the slope, in response to the steering wheel of the electric vehicle turning to the right at an angle greater than a preset angle threshold, the increase in the torque output of the drive system to the right wheel is actively controlled to be smaller than the increase in the torque output of the drive system to the left wheel.

14. The control method according to any one of claims 9 to 13, characterized in that: The control method further comprises: At a third moment after the second moment, in response to the electric vehicle traveling on a slope having a slope greater than a preset slope threshold and a change in the opening of an accelerator pedal of the electric vehicle being greater than a preset change value, the drive system is controlled to output the torque indicated by the torque signal.

15. An electric vehicle, characterized in that: The electric vehicle includes a drive system and a controller, the drive system is used to drive the four wheels of the electric vehicle to rotate, the drive system includes a motor controller as described in any one of claims 1 to 8, and the controller is used to control the drive system to execute the control method as described in any one of claims 9 to 14.

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