A motor controller, a powertrain and a vehicle

Abstract

The present application discloses a motor controller, a powertrain and a vehicle. The motor controller is applied to a drive motor and includes a control device and an inverter circuit. The control device is configured to receive a braking signal of the vehicle, a rotational speed signal of the drive motor, and a torque signal of the drive motor. The control device is further configured to determine that the vehicle is approaching a stop state and thus there is a parking requirement in response to the rotational speed indicated by the rotational speed signal being greater than zero and less than a preset rotational speed, and output a first control signal in response to the braking force indicated by the braking signal being equal to zero and the torque indicated by the torque signal being equal to zero, so as to avoid conflicting with the operation mode intended by the driver. The first control signal is used to control the motor rotational speed to decrease to achieve parking. Since the present application determines vehicle information in the motor controller and controls the motor rotational speed, the control path is shorter and the response speed is faster, thereby enabling rapid and accurate parking.

Description

Technical Field

[0001] This application relates to the field of new energy vehicles, and particularly to a motor controller, a powertrain, and a vehicle. Background Art

[0002] In recent years, new energy vehicles have become the main direction of the transformation and development of the global automotive industry and an important engine for promoting the sustainable growth of the world economy. With the increasing popularity of new energy vehicles and the diversification of road conditions and parking scenarios, the parking function has become the main research direction for each manufacturer.

[0003] When a traditional vehicle parks, various sensors such as radar, laser, sonar, and cameras are usually used to sense the surrounding environment of the vehicle, and then the parking is realized by combining the Autohold function and the Electrical Park Brake (EPB) system.

[0004] However, on the one hand, the above two parking methods have high requirements for vehicles and are not applicable to vehicles without the Autohold function or the EPB system. On the other hand, both of these two parking methods require driver operation, and the control link is long, resulting in problems such as delayed parking and poor parking effect.

[0005] Therefore, how to quickly and accurately control vehicle parking is an urgent problem to be solved at present. Summary of the Invention

[0006] This application provides a motor controller, a powertrain, and a vehicle to solve the problem of how to quickly and accurately control vehicle parking.

[0007] In a first aspect, an embodiment of this application provides a motor controller applied to a drive motor. The motor controller includes a control device and an inverter circuit. The control device is configured to receive a braking signal, a speed signal, and a torque signal. The braking signal is used to indicate the braking force of the vehicle, the speed signal is used to drive the speed of the drive motor, and the torque signal is used to indicate the torque of the drive motor.

[0008] When the braking signal indicates that the braking force is equal to zero, the speed signal indicates that the speed is greater than zero and less than a preset speed, and the torque signal indicates that the torque is equal to zero, the control device is configured to output a first control signal.

[0009] This is because when the braking signal indicates that the braking force is equal to zero, it can be determined that the driver has not braked or pulled the handbrake. If the braking signal indicates that the braking force is not equal to zero, at this time, the control device will conflict with the driver's intended braking method when realizing parking by reducing the speed.

[0010] Secondly, when the torque indicated by the torque signal is equal to zero, it can be determined that the driver has not stepped on the accelerator, avoiding conflicts between the speed control parking method and the parking method intended by the driver. For example, during the uphill process of the vehicle, the driver steps on the accelerator and the vehicle is parked on the slope through the torque control method.

[0011] Thirdly, when the speed indicated by the speed signal is greater than zero and less than the preset speed, it can be determined that the vehicle is approaching a stop state, that is, there is a parking requirement in the current scenario.

[0012] In practical applications, the control device can output a first control signal to control the inverter circuit. For example, in response to the first control signal, the inverter circuit controls the switching tubes of each phase bridge arm in the inverter circuit to conduct or turn off, so as to output a first drive current to the drive motor; wherein, the first drive current is used to reduce the speed of the drive motor.

[0013] It should be noted that the setting of the above preset speed should be close to zero speed, which can reflect that the vehicle is approaching the braking state.

[0014] In addition, compared with the traditional technology in which the motor controller obtains motor information, the vehicle controller formulates a parking strategy and then issues it to the motor controller to implement the parking strategy, the parking strategy of this application is formulated and implemented by the motor controller, the control path is shorter, and the response time is shorter; and for the acquisition of various motor signals, the motor controller belongs to proximal control compared with the vehicle controller, so the acquired signals are not easily deviated, and thus the vehicle parking can be controlled more accurately.

[0015] In a possible implementation manner, the control device outputs a first control signal in response to the braking signal, the torque signal, and the speed signal satisfying a first preset condition; wherein, the first preset condition includes: the braking force indicated by the braking signal is equal to zero, the torque indicated by the torque signal is equal to zero, the speed indicated by the speed signal is greater than zero and less than the preset speed, and the speed indicated by the speed signal continuously decreases within a first preset duration.

[0016] For example, the driver does not step on the brake or the accelerator, the motor speed of the vehicle is small when approaching the stop state, and due to the action of friction, the speed continuously decreases. In this case, the control device accurately determines that the driver has a parking requirement and accelerates the parking by reducing the motor speed.

[0017] It can be understood that if the speed indicated by the speed signal is greater than zero and less than the preset speed, and the speed indicated by the speed signal continuously increases within the first preset duration, and the braking force indicated by the braking signal is equal to zero, and the torque indicated by the torque signal is equal to zero, it can be determined that the driver has no parking requirement under this working condition.

[0018] For example, in the scenario where the vehicle is on a slope and the driver intends to coast downhill without the intention of parking, since the driver does not step on the brake or the accelerator, the rotational speed is relatively small at the beginning of the coasting, but the rotational speed of the motor will continuously increase during the coasting process. Therefore, the parking control strategy should not be applied to avoid conflicting with the driver's intention.

[0019] In a possible implementation manner, the control device responds to successively receiving a braking signal indicating that the braking force is greater than or equal to a preset braking force and a braking signal indicating that the braking force is zero, and when the braking signal indicating that the braking force is zero, the torque signal, and the rotational speed signal meet the second preset condition, the control device outputs a first control signal. Wherein, the second preset condition includes: the duration of the braking signal indicating that the braking force is zero is greater than a second preset duration; within the second preset duration, the driving motor torque indicated by the torque signal is equal to zero; within the second preset duration, the driving motor rotational speed indicated by the rotational speed signal is greater than zero and less than a preset rotational speed.

[0020] It can be understood that in the case of a relatively small rotational speed, it only indicates that the vehicle is approaching a stop state, and it is impossible to accurately judge whether the driver's intention is braking or parking. Therefore, the duration of the braking signal with zero braking force can be further combined to judge the driver's intention;

[0021] Under normal circumstances, if the driver has a temporary braking intention, after releasing the brake, the driver will further drive the vehicle to continue moving by stepping on the accelerator, etc., and the rotational speed of the motor will continue to increase; if the driver has a long-term parking intention, after releasing the brake, the driver will not drive the vehicle anymore, and the rotational speed of the motor will approach zero rotational speed. Therefore, in this working condition, vehicle parking can be achieved by means of rotational speed control.

[0022] For example, in the scenario of yielding to pedestrians, the driver temporarily brakes to a stop. At this time, the braking force is not zero. After the pedestrian passes, the driver releases the brake, and the braking force becomes zero. However, since the driver has not had time to step on the accelerator yet, and the current working condition already meets the conditions of zero braking force, zero torque, and rotational speed approaching zero, triggering motor rotational speed control for parking obviously goes against the driver's intention to continue driving.

[0023] If within the second preset duration, the braking force indicated by the braking signal remains zero continuously, and the torque indicated by the torque signal also remains zero continuously, it means that the driver does not step on the accelerator and has no intention of continuing to drive. Therefore, motor rotational speed control can be triggered for parking.

[0024] In a possible implementation manner, during the process of the control device outputting the first control signal, if the rotational speed indicated by the rotational speed signal is greater than or equal to the preset rotational speed, the control device is used to stop outputting the first control signal.

[0025] It can be understood that during the process of controlling the motor speed to achieve parking, the motor speed does not decrease but increases, indicating that the speed control cannot be achieved through the speed control method. Therefore, the speed control should be exited and parking should be achieved through other means.

[0026] For example, in the scenario of parking on a slope, if the vehicle slides backward and continues to slide backward after speed control, and the motor speed continuously increases until it exceeds the preset speed, it indicates that the speed control cannot stabilize the vehicle to maintain the parking state. Therefore, the speed control should be exited and parking should be achieved through other means.

[0027] In a possible implementation manner, during the process of the control device responding to outputting the first control signal, when the torque indicated by the torque signal is greater than zero, the control device is configured to stop outputting the first control signal and output a second control signal.

[0028] It should be noted that the second control signal is used to control the inverter circuit to output a second drive current; the second drive current is used to adjust the output torque of the drive motor to the torque indicated by the torque signal.

[0029] It can be understood that if during the process of the control device outputting the first control signal, the torque indicated by the torque signal is greater than or equal to the preset torque, it indicates that the required torque of the vehicle is relatively large. At this time, the speed control should be exited and the torque demand of the vehicle should be responded to avoid conflicting with the driver's intention;

[0030] For example, if the driver does not want to continue parking and wants to control the vehicle to move forward and steps on the accelerator pedal, at this time, the control device needs to exit the speed control and control the vehicle to move forward based on the torque indicated by the torque signal.

[0031] Or, when the vehicle is on a slope and the driver wants to park the vehicle by means of torque control and steps on the accelerator pedal, at this time, the control device needs to exit the speed control and control the vehicle to park on the slope based on the torque indicated by the torque signal.

[0032] In a possible implementation manner, during the process of the control device responding to outputting the first control signal, when the braking force indicated by the braking signal is greater than zero, the control device is configured to stop outputting the first control signal.

[0033] It can be understood that if during the process of the control device outputting the first control signal, the braking force indicated by the braking signal is greater than zero, it indicates that the driver has performed operations such as stepping on the brake or pulling the handbrake. At this time, the speed control should be exited to avoid conflicting with the driver's intention;

[0034] It should be noted that during the process of controlling the driving motor speed to decrease, when the driver steps on the brake for parking, since the brake has just been stepped on, the braking force is small and has not reached the preset braking force yet. However, if the speed control is exited until the braking force is greater than the preset braking force, the switching speed of the control strategy will be relatively slow, affecting the parking effect. Therefore, when the braking force is greater than zero, the control device should exit the speed control.

[0035] For example, during the process of the control device controlling the motor speed to decrease, a special road condition occurs and the driver steps on the brake. At this time, the control device needs to exit the motor speed control. Further, if the automatic parking function of the vehicle is turned on when the driver steps on the brake pedal, the Electronic Stability Program (ESP) of the vehicle body will maintain the braking hydraulic pressure at the wheel end, and there is no need to shift to the parking gear, pull the handbrake, or activate the Electrical Park Brake (EPB), etc., to achieve automatic parking.

[0036] In a possible implementation manner, when the control device receives a first gear signal during the process of outputting a first control signal, the control device is used to stop outputting the first control signal; wherein, the gear indicated by the first gear signal is the P gear.

[0037] For example, when the driver shifts to the parking gear to activate the EPB, the motor is locked by the brake caliper to control the vehicle braking, and then the vehicle stabilizes and parks. In this working condition, the control device needs to exit the motor speed control to avoid control mode conflicts.

[0038] In a possible implementation manner, when the duration of the first drive current output by the inverter circuit is greater than a third preset duration, the control device is used to stop outputting the first control signal.

[0039] It can be understood that if the output duration of the first drive current is too long, it means that the method of controlling the speed cannot achieve parking, and continuous output of the drive current poses a risk of system overheating. Therefore, in this working condition, the speed control should be exited.

[0040] In a possible implementation manner, when the control device is outputting the first control signal, if the duration during which the speed signal indicates a speed of zero and the torque signal indicates a non-zero torque is greater than a preset duration, the control device is used to stop outputting the first control signal.

[0041] It can be understood that if the motor is blocked during the process of the control device outputting the first control signal, and the blocked state continues to exceed a fourth preset duration, at this time, the control device needs to exit the speed control to avoid the risk of overheating caused by the motor being blocked for too long.

[0042] For example, in the scenario of a vehicle parked on a slope, due to long-term parking, the motor continues to output torque even when the rotational speed is zero, and the motor continuously heats up. In this working condition, the control device needs to exit the rotational speed control and park the vehicle through other means.

[0043] It should be understood that the fourth preset duration can be set with reference to the motor performance and vehicle requirements, and is not limited here.

[0044] In a possible implementation manner, when the amplitude of the first drive current is greater than the preset amplitude, the control device is used to stop outputting the first control signal.

[0045] It can be understood that if the amplitude of the first drive current is greater than the preset amplitude, on the one hand, it indicates that it is difficult to achieve parking through rotational speed control, and on the other hand, too large a current is likely to cause a risk of overheating of the motor controller. Therefore, in this working condition, the control device needs to exit the rotational speed control and achieve parking through other means.

[0046] In a possible implementation manner, the torque signal comes from any one of the accelerator pedal sensor, accelerator pedal controller, and vehicle controller.

[0047] In a possible implementation manner, the control device can receive a braking signal from the vehicle controller. Additionally, it can directly obtain the braking signal from the brake controller, shortening the control path and improving the braking response speed, so as to quickly control the vehicle to enter the parked state.

[0048] In a possible implementation manner, the drive motor is provided with a rotational speed sensor for collecting rotational speed signals.

[0049] For example, the above rotational speed sensor can be a motor resolver. In actual applications, the motor rotational speed information can be obtained through the motor resolver signal of the motor resolver, thereby obtaining a shorter control link, and using the high resolution and high real-time characteristics of the motor resolver signal to quickly and accurately achieve rotational speed control.

[0050] In a possible implementation manner, when the rotational speed indicated by the rotational speed signal is greater than or equal to the preset rotational speed during the process of outputting the first control signal, the control device is used to output a braking request signal to the brake controller.

[0051] In a possible implementation manner, when the rotational speed indicated by the rotational speed signal is greater than or equal to the preset rotational speed during the process of outputting the first control signal, the control device is used to output a gear control signal to the gear controller; wherein, the gear control signal is used to control the vehicle to run in the parking gear.

[0052] It can be understood that if the motor speed increases instead of decreasing during the output of the first control signal, and even is greater than or equal to the preset speed, it indicates that the speed control cannot achieve parking. Therefore, it is necessary to exit the speed control and other control methods are needed to assist in parking.

[0053] In a second aspect, an embodiment of the present application further provides a powertrain, which includes a motor controller and a drive motor as described in any one of the first aspects.

[0054] In a third aspect, an embodiment of the present application further provides a vehicle, which includes a power battery and the powertrain as described in the second aspect; the power battery is used to supply power to the inverter circuit of the powertrain.

[0055] It should be understood that the implementation and beneficial effects of the above-mentioned multiple aspects of the present application can be referred to each other. BRIEF DESCRIPTION OF THE DRAWINGS

[0056] Figure 1 It is a schematic structural diagram of a motor controller provided by an embodiment of the present application;

[0057] Figure 2 It is a schematic structural diagram of an inverter circuit provided by an embodiment of the present application;

[0058] Figure 3a It is a schematic diagram of a vehicle control system architecture provided by an embodiment of the present application;

[0059] Figure 3b It is another schematic diagram of a vehicle control system architecture provided by an embodiment of the present application;

[0060] Figure 4 It is a control timing diagram of a motor controller provided by an embodiment of the present application;

[0061] Figure 5a It is another control timing diagram of a motor controller provided by an embodiment of the present application;

[0062] Figure 5b It is another control timing diagram of a motor controller provided by an embodiment of the present application;

[0063] Figure 6a It is another control timing diagram of a motor controller provided by an embodiment of the present application;

[0064] Figure 6b It is another control timing diagram of a motor controller provided by an embodiment of the present application;

[0065] Figure 7a It is another control timing diagram of a motor controller provided by an embodiment of the present application;

[0066] Figure 7bAnother control timing diagram of the motor controller provided by the embodiment of the present application;

[0067] Figure 8a Another control timing diagram of the motor controller provided by the embodiment of the present application;

[0068] Figure 8b Another control timing diagram of the motor controller provided by the embodiment of the present application;

[0069] Figure 8c Another control timing diagram of the motor controller provided by the embodiment of the present application;

[0070] Figure 9 Another control timing diagram of the motor controller provided by the embodiment of the present application;

[0071] Figure 10 Another control timing diagram of the motor controller provided by the embodiment of the present application;

[0072] Figure 11 Another control timing diagram of the motor controller provided by the embodiment of the present application;

[0073] Figure 12 Another control timing diagram of the motor controller provided by the embodiment of the present application;

[0074] Figure 13a A structural schematic diagram of a powertrain provided by the embodiment of the present application;

[0075] Figure 13b Another structural schematic diagram of a powertrain provided by the embodiment of the present application;

[0076] Figure 14 A structural schematic diagram of a vehicle provided by the embodiment of the present application;

[0077] Figure 15 A flowchart of a parking method provided by the embodiment of the present application. Detailed implementation manners

[0078] In order to make the objectives, technical solutions and advantages of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present application.

[0079] To facilitate the understanding of the embodiments of the present application, the terms involved in the embodiments of the present application will be explained below:

[0080] I. Electronic Stability Program (ESP)

[0081] The ESP is mainly used to analyze the vehicle information sent by various sensors. If the driver has activated the auto hold function, after the driver steps on the brake pedal, the ESP will continue to maintain the braking hydraulic pressure at the wheel ends, control the hydraulic braking system, and park the vehicle. For example, the ESP brakes by hydraulically clamping the brake calipers or brake discs through the hydraulic system.

[0082] II. Electronic Parking Brake (EPB)

[0083] The EPB is mainly used to control the parking brake according to the electronic circuit. Its function is similar to that of a mechanical lever handbrake. Specifically, when the driver shifts into the P gear and activates the EPB, the controller of the EPB sends an instruction to clamp the rear-wheel brake calipers through the locking motor. For example, when the driver pulls the handbrake, the EPB uses the motor to hold against the brake disc to brake the vehicle.

[0084] III. Vehicle Controller Unit (VCU)

[0085] The vehicle controller is mainly used to collect the motor and battery status, accelerator pedal signal, brake pedal signal, and other actuator sensor controller signals. Combining with the driver's driving intention, after comprehensive analysis and making corresponding judgments, it monitors the actions of each component controller at the lower layer, so as to ensure that the whole vehicle works normally and stably under good power performance, high economy, and reliability conditions.

[0086] IV. Automatic Gear Positions

[0087] The automatic gear positions are generally divided into four gears: P, R, N, and D, which respectively represent the positions where the gear lever is shifted; among them, the P gear is the parking gear; the R gear is the reverse gear; the N gear is the neutral gear; the D gear is the forward gear.

[0088] To make the purpose, technical solutions, and advantages of this application clearer, the following will further describe this application in detail in combination with the application background.

[0089] As the global automotive industry is developing towards electrification, intelligence, networking, and sharing, consumers' quality requirements and consumption experiences for electric vehicle products are also getting higher and higher. Among them, the parking function of the vehicle is an important function that affects the driving comfort of customers.

[0090] However, the traditional parking function has various defects, such as single applicable scenarios, excessive vehicle configuration requirements, and untimely parking responses.

[0091] Taking the Autohold function as an example, when the Autohold function is turned on, after the driver steps on the brake pedal to stop the vehicle, the ESP will continue to maintain the braking hydraulic pressure at the wheel end and control the vehicle to park through the hydraulic braking system.

[0092] Taking the EPB function as an example, it is necessary to manually stop the vehicle and then activate the EPB function, or the vehicle controller formulates a control strategy to activate the EPB function based on the vehicle information received from various sensors to achieve electronic parking.

[0093] It can be found that both of these two control methods require driver participation to varying degrees, but the reaction speed of people far cannot meet the response speed requirements for parking. In addition, by integrating information through the vehicle controller to formulate strategies, there are many hardware devices that need to interact, and the control chain is too long, which further affects the control delay. In addition, there are a large number of vehicles on the market that do not have the above parking functions, so the parking needs of users cannot be met.

[0094] Therefore, how to quickly and accurately achieve parking is an urgent problem to be solved at present.

[0095] Based on the above problems, an embodiment of the present application provides a motor controller, as Figure 1 shown. The motor controller 101 is applied to a drive motor 102. The motor controller 101 includes a control device 1011 and an inverter circuit 1012;

[0096] The control device 1011 is configured to receive a braking signal, a rotational speed signal, and a torque signal;

[0097] It should be noted that the braking signal is used to indicate the braking force of the vehicle, the rotational speed signal is used to indicate the rotational speed of the drive motor 102, and the torque signal is used to indicate the torque of the drive motor 102;

[0098] The control device 1011 is further configured to output a first control signal in response to the braking signal indicating that the braking force is equal to zero, the rotational speed signal indicating that the rotational speed is greater than zero and less than a preset rotational speed, and the torque signal indicating that the torque is equal to zero;

[0099] It should be noted that the first control signal output by the control device 1011 is used to control the inverter circuit 1012 to output a first drive current; the first drive current is used to reduce the rotational speed of the drive motor 102.

[0100] For example, as Figure 2As shown, the inverter circuit 1012 includes switching transistors Q1 - Q6. Among them, switching transistors Q1 and Q2 form the first bridge arm, switching transistors Q3 and Q4 form the second bridge arm, switching transistors Q5 and Q6 form the third bridge arm. The control terminals of switching transistors Q1 - Q6 are connected to the control device 1011. Each bridge arm is connected in parallel to the power battery 1401 and the capacitor C1. The mid - points U of the first bridge arm, V of the second bridge arm, and W of the third bridge arm are respectively connected to the multi - phase windings L1 - L3 of the motor.

[0101] In response to the first control signal, the inverter circuit 1012 controls the switching transistors Q1 - Q6 of each phase bridge arm in the inverter circuit 1012 to conduct or turn off, so as to output a first drive current to the drive motor 102, thereby reducing the speed of the drive motor 102.

[0102] It should also be noted that when the speed indicated by the speed signal is greater than zero and less than the preset speed, it can be determined that the vehicle is approaching the stop state, that is, there is a parking demand in the current scenario. For example, when the driver does not step on the accelerator and does not step on the brake, and the motor speed is 10 revolutions per minute, which is less than the preset speed of 100 revolutions per minute, the control device 1011 can determine that the vehicle is in a state of approaching but not stopping. Therefore, parking can be achieved by outputting a first control signal to reduce the motor speed.

[0103] When the braking signal indicates that the braking force is equal to zero, it can be determined that the driver does not brake or does not pull the handbrake. On the contrary, if the braking signal indicates that the braking force is not equal to zero, it can be determined that the driver intends to brake. At this time, if the control device 1011 realizes parking by reducing the speed, it will conflict with the driver's intention. For example, when the vehicle encounters an obstacle on the road, the driver immediately steps on the brake for safety reasons. At this time, although the motor speed drops to 10 revolutions per minute, which is less than the preset speed of 100 revolutions per minute, since the braking force indicated by the braking signal is not zero, the control device 1011 cannot control the motor speed to drop, otherwise it will conflict with the driver's intention.

[0104] When the torque signal indicates that the torque is equal to zero, it can be determined that the driver does not step on the accelerator, avoiding the conflict between the way of parking by speed control and the driver's intention. For example, during the process of the vehicle slowly climbing a slope, the motor speed is 80 revolutions per minute, which is less than the preset speed of 100 revolutions per minute, but the driver steps on the accelerator and intends to achieve vehicle slope parking through torque control. Since the torque indicated by the torque signal is not zero, the control device 1011 cannot control the motor speed to drop, otherwise it will conflict with the driver's intention. Or, during the vehicle starting process, the motor speed is 10 revolutions per minute, which is less than the preset speed of 100 revolutions per minute, and the driver gently steps on the accelerator to accelerate. Since the torque indicated by the torque signal is not zero, the control device 1011 cannot control the motor speed to drop, otherwise it will conflict with the driver's intention.

[0105] Therefore, after meeting the above response conditions, the control device 1011 can achieve parking by reducing the rotational speed.

[0106] The following introduces the above signal sources in combination with the vehicle control system architecture:

[0107] As Figure 3a and Figure 3b shown, in addition to the above-mentioned motor controller 101, the vehicle control system architecture further includes a vehicle controller 301, a body electronic stability system 302, an electronic parking brake system 303, a gear controller 304, an accelerator pedal sensor 305, an accelerator pedal controller 306, and a brake controller 307:

[0108] As Figure 3a shown, the accelerator pedal sensor 305 establishes a communication connection with the accelerator pedal controller 306, and the vehicle controller 301 respectively establishes communication connections with the brake controller 307, the accelerator pedal controller 306, the gear controller 304, the body electronic stability system 302, and the electronic parking brake system 303. The vehicle controller 301 directly communicates with the control device 1011.

[0109] As Figure 3b shown, the control device 1011 of the motor controller 101 respectively establishes communication connections with the brake controller 307, the gear controller 304, the accelerator pedal controller 306, the vehicle controller 301, the body electronic stability system 302, and the electronic parking brake system 303. The accelerator pedal sensor 305 establishes a communication connection with the accelerator pedal controller 306.

[0110] It can be understood that based on Figure 3a or Figure 3b the device communication connection principle, other hardware architectures with the same or similar concepts can be derived, which will not be elaborated here.

[0111] In Figure 3a or Figure 3b the hardware construction of the vehicle control system shown, if the hardware of the signal source communicates with the motor controller 101 indirectly through the vehicle controller 301, the control device 1011 can receive signals from the vehicle controller 301. If the hardware of the signal source communicates directly with the motor controller 101, the control device 1011 can directly obtain signals.

[0112] In a possible implementation manner, the torque signal comes from any one of the accelerator pedal sensor 305, the accelerator pedal controller 306, and the vehicle controller 301.

[0113] For example, the control device 1011 can receive a torque signal from the vehicle controller 301, or directly obtain the torque signal from the accelerator pedal sensor 305 or the accelerator pedal controller 306, shortening the control path and improving the braking response speed. Similarly, the control device 1011 receives a braking signal from the vehicle controller 301, or directly obtains the braking signal from the brake controller 307; the same applies to the way the control device 1011 obtains the gear control signal, which will not be elaborated here.

[0114] In a possible implementation, the drive motor 102 is provided with a speed sensor for collecting speed signals.

[0115] For example, an electric machine resolver provided on the motor rotor, the control device 1011 can obtain the motor speed information by acquiring the electric machine resolver signal of the electric machine resolver, thereby obtaining a shorter control link, and using the high resolution and high real-time characteristics of the electric machine resolver signal to quickly and accurately implement braking control.

[0116] Based on the motor controller 101 provided in the embodiments of the present application, the parking function in multiple scenarios can be realized, and the requirements for vehicle configuration are relatively low. It is not necessary to combine the vehicle configuration with the Autohold function or the EPB function to realize parking.

[0117] Secondly, compared with implementing the parking algorithm in the body electronic stability system 302 or the vehicle controller 301 in the traditional technology, the parking strategy of the present application is formulated and implemented in the motor controller, and the control path is shorter. Moreover, for the acquisition of various motor signals, the motor controller 101 belongs to proximal control compared with the vehicle controller 301. Therefore, the acquired signals are not likely to deviate, and thus the vehicle parking can be controlled more accurately.

[0118] Therefore, in practical applications, if the required torque obtained by the vehicle controller 301 is zero, it is determined that there is no risk of vehicle rollback and parking is not required. However, under the same road conditions and vehicle conditions, the motor controller determines that the vehicle is likely to roll backward with higher accuracy, and then the speed braking is preferentially performed based on the judgment of the motor controller.

[0119] Secondly, in the embodiments of the present application, the controller can directly generate a speed control signal and directly control the speed of the motor without torque calculation, further reducing the information transfer time and having high control accuracy.

[0120] Through simulation experiment comparison, compared with the traditional technology of obtaining motor information through the motor controller - formulating the parking strategy by the vehicle controller - implementing the parking strategy by the motor controller, the parking control delay of the present application can be shortened by more than 50 ms.

[0121] The functions of the motor controller 101 will be described in detail below in combination with the above signal sources and different control methods:

[0122] 1. The motor controller realizes vehicle parking by controlling the rotational speed

[0123] Embodiment 1

[0124] As Figure 1 shown, the motor controller includes a control device 1011 and an inverter circuit 1012;

[0125] The control device 1011 responds to the braking signal indicating that the braking force is zero, the rotational speed signal indicating that the rotational speed is greater than zero and less than the preset rotational speed, and the torque signal indicating that the torque is zero. The control device 1011 is used to output a first control signal.

[0126] It should be noted that the first control signal output by the control device 1011 is used to control the inverter circuit 1012 to output a first drive current; the first drive current is used to reduce the rotational speed of the drive motor 102.

[0127] For example, when the driver releases the brake pedal on a slope and does not step on the accelerator pedal, due to the slope, the motor rotational speed is 10 revolutions per minute, indicating that the vehicle has a rolling-back condition. However, the motor rotational speed is small and does not exceed the preset rotational speed of 100 revolutions per minute, indicating that the vehicle has just started to roll back. Therefore, in this scenario, it is necessary to control the vehicle to stabilize and park on the slope;

[0128] Another example is when the driver wants to slowly park the vehicle under the action of resistance. The motor rotational speed drops below the preset rotational speed of 100 revolutions per minute. Therefore, the braking duration can be shortened and the parking response can be accelerated by controlling the motor rotational speed to drop through the motor controller.

[0129] Exemplarily, as Figure 4 shown in the control timing diagram, at time t0, the braking signal indicates that the braking force is zero, the rotational speed signal indicates that the rotational speed is greater than zero and less than the preset rotational speed, and the torque signal indicates that the torque is zero. The control device 1011 responds and starts to output the first control signal;

[0130] Furthermore, under the control of the first control signal, the rotational speed continuously drops, and the rotational speed drop signal indicating the rotational speed also continuously drops. At time t1, the rotational speed of the drive motor 102 drops to zero.

[0131] The motor controller of the embodiment of the present application accurately judges whether the driver has a parking intention through the magnitude of the rotational speed indicated by the rotational speed signal, broadens the application scenario of the parking function, and improves the accuracy of identifying the parking demand. In addition, by combining the magnitudes of the braking signal and the torque signal, conflicts with other control methods selected by the driver are avoided, and the control accuracy is further improved.

[0132] Embodiment 2

[0133] When the control device 1011 responds to the brake signal, torque signal, and rotational speed signal satisfying a first preset condition, the control device 1011 is configured to output a first control signal. The first preset condition includes: the braking force indicated by the brake signal is equal to zero, the torque indicated by the torque signal is equal to zero, the rotational speed indicated by the rotational speed signal is greater than zero and less than a preset rotational speed, and the rotational speed indicated by the rotational speed signal continuously decreases within a first preset duration.

[0134] For example, in the scenario where the vehicle is on a slope and the driver intends to coast downhill without the intention of parking, since the driver does not step on the brake or the accelerator, the rotational speed is relatively small at the beginning of the coasting, but the rotational speed of the motor will continuously increase during the coasting process;

[0135] As Figure 5a shown, at time t0, the braking force indicated by the brake signal is equal to zero, the torque indicated by the torque signal is equal to zero, and the rotational speed indicated by the rotational speed signal is greater than zero and less than the preset rotational speed; within the first preset duration T1, the rotational speed indicated by the rotational speed signal continuously increases. Obviously, in this scenario, if the control device 1011 performs parking control, it will conflict with the driver's driving intention. Therefore, there is no need to output the first control signal (for convenience of observation, Figure 5a in this and other control timing diagrams, the first control signal being zero indicates that the first control signal is not output, which will not be elaborated further).

[0136] Exemplarily, the preset rotational speed of the motor is 100 revolutions per minute, and the first preset duration T1 is 20 seconds. The driver intends to coast and does not step on the brake or the accelerator, and the vehicle travels by itself. The rotational speed of the motor continuously increases within 20 seconds, rising from 10 revolutions per minute to 50 revolutions per minute. In this case, the control device 1011 does not output the first control signal to avoid conflicting with the driver's intention.

[0137] Therefore, it is necessary to further determine whether the driver attempts to park by combining the change trend of the rotational speed signal.

[0138] For example, as Figure 5b shown, at time t0, the driver does not step on the brake or the accelerator, the braking force indicated by the brake signal is equal to zero, the torque indicated by the torque signal is equal to zero, and the rotational speed indicated by the rotational speed signal is greater than zero and less than the preset rotational speed; within the first preset duration T1, under the influence of road friction, the rotational speed indicated by the rotational speed signal continuously decreases. In this case, the control device 1011 accurately determines that the driver has a parking requirement and outputs the first control signal at time t1 to accelerate the reduction of the motor rotational speed, thereby reducing the motor rotational speed to zero at time t2 to achieve parking.

[0139] Exemplarily, the preset rotational speed of the motor is 100 revolutions per minute, and the first preset duration T1 is 20 seconds. The driver intends to park the vehicle by means of friction, without stepping on the brake or the accelerator. The vehicle travels by itself. Within 20 seconds, the rotational speed of the motor continuously decreases from 200 revolutions per minute to 100 revolutions per minute. The control device 1011 outputs a first control signal to reduce the rotational speed of the motor to zero.

[0140] The motor controller according to the embodiment of the present application accurately determines whether the driver's intention is to park or to drive based on the magnitude of the rotational speed indicated by the rotational speed signal and the change trend of the rotational speed, broadens the application scenario of the parking function, and improves the accuracy of identifying the parking requirement. In addition, by combining the magnitudes of the braking signal and the torque signal, conflicts with other control methods selected by the driver are avoided, and the control accuracy is further improved.

[0141] Embodiment III

[0142] The control device 1011 responds to successively receiving a braking signal indicating that the braking force is greater than or equal to the preset braking force and a braking signal indicating that the braking force is zero, and the braking signal indicating that the braking force is zero, the torque signal, and the rotational speed signal satisfy the second preset condition. The control device 1011 is configured to output a first control signal. The second preset condition includes: the duration of the braking signal indicating that the braking force is zero is greater than the second preset duration; within the second preset duration, the torque of the drive motor 102 indicated by the torque signal is equal to zero; within the second preset duration, the rotational speed of the drive motor 102 indicated by the rotational speed signal is greater than zero and less than the preset rotational speed.

[0143] Under normal circumstances, the braking force being zero may mean that the driver intends to temporarily brake. For example, when encountering an obstacle on the road or giving way to pedestrians, etc., after releasing the brake, the driver will further drive the vehicle to continue moving by stepping on the accelerator, etc., and the rotational speed of the motor will continuously increase;

[0144] In addition, the braking force being zero may also mean that the driver intends to park for a long time. After releasing the brake, the driver will not drive the vehicle anymore, and the rotational speed of the motor will approach zero rotational speed.

[0145] Therefore, in the condition of a relatively small rotational speed, it only shows that the vehicle is approaching a stop state, and it is impossible to accurately determine whether the driver's intention is to brake or to park. Therefore, it is necessary to further combine the duration of the braking signal with zero braking force and the signal change to determine the driver's intention;

[0146] For example, in the scenario of encountering pedestrians, such as Figure 6aAs shown, at time t0, the driver steps on the brake to control the vehicle to decelerate. The braking force indicated by the braking signal is not zero, the rotational speed indicated by the rotational speed signal decreases due to braking, and the torque indicated by the torque signal is zero. After the pedestrian passes, the driver releases the brake and steps on the accelerator to continue driving. That is, at time t1, the braking force indicated by the braking signal is zero, the torque indicated by the torque signal is greater than zero, and the rotational speed indicated by the rotational speed signal is greater than zero. Moreover, within the second preset duration T2, the rotational speed of the motor has not exceeded the preset rotational speed. In this case, the control device 1011 accurately determines that the driver has a driving requirement based on the torque change signal within the second preset duration T2 and does not output the first control signal to avoid conflicting with the driver's intention.

[0147] For another example, when the driver wants to park the vehicle and steps on the brake to control the vehicle to decelerate, when the vehicle speed is relatively low, that is Figure 6b In the figure, at time t0, the rotational speed indicated by the rotational speed signal is greater than zero, and within t0 - t1, the rotational speed of the driving motor 102 continues to decrease. Additionally, the torque indicated by the torque signal is zero, and the braking force indicated by the first braking signal is not zero. If within the second preset duration T2, the braking force indicated by the braking signal is zero and the torque indicated by the torque signal also remains zero, it indicates that the driver has not stepped on the accelerator and has no intention of continuing to drive. Moreover, within the second preset duration T2, the rotational speed indicated by the rotational speed signal is greater than zero and less than the preset rotational speed, indicating that the vehicle is approaching the parking state. Therefore, the control device 1011 outputs the first control signal at time t2 to control the rotational speed of the motor to decrease and quickly and accurately achieve parking.

[0148] The motor controller according to the embodiment of the present application combines the changing trends of the rotational speed signal, the braking signal, and the torque signal to accurately determine whether the driver's intention is to park or drive, and avoid conflicting with other control methods selected by the driver, broadening the application scenario of the parking function and improving the accuracy of identifying the parking requirement.

[0149] Second, when the motor controller cannot achieve parking by controlling the rotational speed, assist other control methods to achieve parking

[0150] First, introduce the vehicle conditions where rotational speed control cannot achieve parking by way of embodiments:

[0151] Embodiment 1

[0152] The control device 1011 stops outputting the first control signal in response to the duration of the first drive current output by the inverter circuit 1012 being greater than the third preset duration.

[0153] It can be understood that during the process of the motor controller controlling the driving motor 102 to reduce its rotational speed to achieve the parking of the electric vehicle, if the duration of the first drive current output is too long, it indicates that it is difficult for the motor controller to control the rotational speed of the motor to reduce the rotational speed of the motor and thus difficult to achieve parking. Moreover, with the continuous output of the drive current, there is a risk of system overheating. Therefore, in this operating condition, the rotational speed control should be exited.

[0154] For example, when the electric vehicle is on a slope, due to the large slope, the tendency of the electric vehicle to roll back is obvious. As Figure 7a shown, at time t0, the vehicle starts to roll back, and the rotational speed of the motor indicated by the rotational speed signal gradually increases. At time t1, the braking signal indicates that the braking force is equal to zero, the rotational speed indicated by the rotational speed signal is greater than zero and less than the preset rotational speed, and the torque indicated by the torque signal is equal to zero. The control device 1011 starts to output the first control signal. Until time t2, the duration of the control device 1011 outputting the first control signal exceeds the third preset duration T3, indicating that the motor controller outputs the first drive current for a long time, but the rotational speed control of the control device 1011 cannot achieve the vehicle staying on the slope;

[0155] Therefore, if the rotational speed control is not exited and other control methods are used to achieve the vehicle staying on the slope, there will be risks of vehicle rollback and system overheating. Then, at time t2, the control device 1011 stops outputting the first control signal, and the first drive current drops to zero. Further, the control device 1011 can control the vehicle to park in other ways. For example, as Figure 7a shown, at time t2, through the control method of the braking system, the braking force indicated by the braking signal is greater than zero, the torque indicated by the torque signal is zero, and the rotational speed indicated by the rotational speed signal gradually drops to zero, achieving stable parking.

[0156] Exemplarily, the third preset duration T3 is 5 minutes. When the duration of the control device 1011 outputting the first control signal reaches 5 minutes, the rotational speed control should be exited at this time, that is, the control device 1011 stops outputting the first control signal and stabilizes the vehicle through other methods, such as providing braking force through the braking system, etc., to achieve parking.

[0157] In this embodiment, it is judged whether the rotational speed control can achieve parking by the duration of the first drive current output. When it is difficult for the rotational speed control to achieve parking, the rotational speed control is exited to avoid the risk of system overheating, and parking is achieved by combining other control methods.

[0158] Embodiment 2

[0159] In response to the amplitude of the first drive current being greater than the preset amplitude, the control device 1011 is configured to stop outputting the first control signal.

[0160] It can be understood that if the amplitude of the first drive current is greater than the preset amplitude, on the one hand, it indicates that it is difficult to achieve vehicle parking by speed control, and on the other hand, too large a current is likely to cause the risk of overheating of the motor controller. Therefore, in this working condition, the control device 1011 needs to exit the speed control and achieve vehicle parking by other means.

[0161] For example, when an electric vehicle is on a slope, due to the large slope, the tendency of the electric vehicle to roll back is obvious. As Figure 7b shown, at time t0, the vehicle starts to roll back, and the motor speed indicated by the speed signal gradually increases. At time t1, the braking signal indicates that the braking force is equal to zero, the speed indicated by the speed signal is greater than zero and less than the preset speed, and the torque indicated by the torque signal is equal to zero. The control device 1011 starts to output the first control signal. During the process of the control device 1011 outputting the first control signal, if the amplitude of the first drive current is greater than the preset amplitude, it indicates that the speed control of the control device 1011 cannot achieve vehicle slope parking, and there is a risk of overheating in the system.

[0162] Therefore, if the speed control is not exited to achieve vehicle slope parking by other control methods, there will be a risk of vehicle rollback and system overheating. Then, at time t2, the control device 1011 stops outputting the first control signal, and the first drive current drops to zero. Further, the control device 1011 can control vehicle parking by other means. For example, as Figure 7b shown, at time t2, by means of controlling the braking system, the braking force indicated by the braking signal is greater than zero, the torque indicated by the torque signal is zero, and the speed indicated by the speed signal gradually drops to zero, realizing stable vehicle parking.

[0163] Exemplarily, the preset amplitude of the first drive current is 20 A. If the amplitude of the first drive current output by the inverter circuit 1012 is 21 A, then the speed control should be exited at this time, that is, the control device 1011 stops outputting the first control signal and prevents the electric vehicle from rolling back by other means.

[0164] In this embodiment, the amplitude of the first drive current is used as the judgment condition, avoiding the risk of vehicle rollback caused by the difficulty of achieving vehicle parking by speed control, and at the same time avoiding the risk of overheating of the motor controller caused by too large a current. Therefore, the control device 1011 needs to exit the speed control and achieve vehicle parking by other control methods.

[0165] Embodiment 3

[0166] In a possible implementation manner, during the process of the control device 1011 responding to the output of the first control signal, when the speed indicated by the speed signal is greater than or equal to the preset speed, the control device 1011 is configured to stop outputting the first control signal.

[0167] It can be understood that during the process of the motor controller controlling the driving motor 102 to reduce its speed to achieve the parking of the electric vehicle, if the motor speed does not decrease but increases instead and even exceeds the preset speed, it indicates that it is difficult for the motor controller to control the motor speed to decrease and thus difficult to achieve parking. Therefore, in this working condition, the speed control should be exited.

[0168] For example, when the electric vehicle is on a slope, due to the large slope, the tendency of the electric vehicle to roll back is obvious. As Figure 8a shown, at time t0, the vehicle starts to roll back, and the motor speed indicated by the speed signal gradually increases. At time t1, the braking signal indicates that the braking force is equal to zero, the speed signal indicates that the speed is greater than zero and less than the preset speed, and the torque signal indicates that the torque is equal to zero. The control device 1011 starts to output the first control signal. However, at time t2, the speed indicated by the speed signal exceeds the preset speed, indicating that the speed control of the control device 1011 cannot achieve the vehicle's slope parking.

[0169] Therefore, if the speed control is not exited and other control methods are used to achieve the vehicle's slope parking, there will be a risk of rolling back. Then, at time t2, the control device 1011 stops outputting the first control signal. Further, the control device 1011 can control the vehicle to park in other ways. For example, as Figure 8a shown, at time t2, through the control method of the braking system, the braking signal indicates that the braking force is greater than zero, the torque signal indicates that the torque is zero, and the speed indicated by the speed signal gradually decreases to zero, achieving stable parking.

[0170] Exemplarily, the preset motor speed is 100 revolutions per minute. When the vehicle rolls back and causes the motor speed to exceed 100 revolutions per minute, and the speed signal indicates that the speed is greater than or equal to 100 revolutions per minute during the process of the control device 1011 responding to output the first control signal, the speed control is exited and other control methods are used to prevent the electric vehicle from rolling back.

[0171] The motor controller provided by the embodiment of the present application realizes the function of achieving parking through other control methods in the case where the speed control cannot achieve parking, thereby improving the safety of parking.

[0172] In addition, in the embodiment of the present application, the vehicle speed can also be used as a judgment condition. For example, when the vehicle speed is greater than the preset vehicle speed during the process of the control device 1011 responding to output the first control signal, the control device 1011 exits the speed control and realizes parking through other control methods.

[0173] Embodiment 4

[0174] During the process of the control device 1011 responding to output the first control signal, if the duration for which the speed signal indicates that the speed is zero and the torque signal indicates that the torque is not zero is greater than the fourth preset duration, the control device 1011 is used to stop outputting the first control signal.

[0175] It is understandable that if the motor gets stuck during the process of the control device 1011 outputting the first control signal, and the stuck state persists for more than the fourth preset duration, at this time, the control device 1011 needs to exit the speed control to avoid the risk of overheating caused by the motor being stuck for too long.

[0176] For example, an electric vehicle is in a parked state through speed control on a slope. As Figure 9 shown, at time t0, the control device 1011 outputs the first control signal, the speed indicated by the speed signal is zero, but the torque indicated by the torque signal is not zero. When the duration that the speed indicated by the speed signal is zero and the torque indicated by the torque signal is not zero is greater than the fourth preset duration, due to long-term parking, the motor still continuously outputs torque when the speed is zero, and the motor continuously heats up. In this working condition, the control device 1011 stops outputting the first control signal and realizes vehicle slope parking in other control modes.

[0177] Exemplarily, the fourth preset duration is 10 minutes. During the process of the control device 1011 performing speed control to achieve parking, if the duration of the motor being stuck exceeds 10 minutes, the control device 1011 stops outputting the first control signal and realizes vehicle slope parking in other control modes.

[0178] The motor controller provided by the embodiment of the present application realizes the function of parking in other control modes when the motor is stuck for too long, thereby improving the safety of parking.

[0179] Next, it is introduced how the motor controller realizes parking in other control modes in the above embodiment:

[0180] In a possible implementation manner, taking Embodiment 3 as an example, when the speed indicated by the speed signal is greater than or equal to the preset speed during the process of the control device 1011 responding to the output of the first control signal, the control device 1011 is used to output a braking request signal to the brake controller 307.

[0181] During the process of the motor controller controlling the speed of the drive motor 102 to decrease to achieve parking of the electric vehicle, if the speed of the drive motor 102 is greater than the preset speed, at this time, the control device 1011 outputs a braking request signal to the brake controller 307, and the brake controller 307 controls the braking system to output a braking force in response to the braking request signal to control the speed of the electric vehicle motor to decrease.

[0182] For example, when an electric vehicle is on a slope and due to the large slope, the tendency of the electric vehicle to slide is obvious. As Figure 8b shown, at time t0, the vehicle starts to slide, and the speed of the motor indicated by the speed signal gradually increases;

[0183] At time t1, the braking signal indicates that the braking force is equal to zero, the rotational speed signal indicates that the rotational speed is greater than zero and less than the preset rotational speed, and the torque signal indicates that the torque is equal to zero. The control device 1011 starts to output the first control signal. However, the rotational speed indicated by the rotational speed signal exceeds the preset rotational speed, indicating that the rotational speed control of the control device 1011 cannot achieve vehicle hill parking.

[0184] At time t2, the control device 1011 outputs a braking request signal to the brake controller 307. The braking signal indicates that the braking force is greater than zero, the torque signal indicates that the torque is zero, and the rotational speed signal indicates that the rotational speed continuously decreases to zero.

[0185] Exemplarily, the preset rotational speed of the motor is 100 revolutions per minute. The vehicle rolls backward, causing the rotational speed of the motor to exceed 100 revolutions per minute. In response to the rotational speed signal indicating that the rotational speed is greater than or equal to 100 revolutions per minute during the process of outputting the first control signal, the control device 1011 exits the rotational speed control and provides braking force through the braking system to prevent the electric vehicle from rolling backward.

[0186] The motor controller provided by the embodiment of the present application realizes the function of sending a signal to the brake controller 307 to achieve vehicle parking when the rotational speed control cannot achieve parking, thereby improving the safety of parking.

[0187] In addition, different from the traditional technology in which the vehicle controller 301 outputs a braking request signal, the braking request signal in the present application is output by the motor controller, which can shorten the control path, achieve rapid braking, and thus achieve rapid parking.

[0188] It should be noted that the embodiment of the present application can also use the vehicle speed as a judgment condition. For example, in response to the vehicle speed being greater than the preset vehicle speed during the process of outputting the first control signal, the control device 1011 outputs a braking request signal to the brake controller 307.

[0189] It can be understood that the above braking system parking method can also be applied to other vehicle conditions where the rotational speed control cannot achieve parking.

[0190] Based on the same technical concept, the control device 1011 can also be used to output a manual braking signal in response to the rotational speed signal indicating that the rotational speed is greater than or equal to the preset rotational speed and other vehicle conditions where the rotational speed braking cannot achieve parking, so as to remind the driver to perform manual braking for parking.

[0191] For example, when the vehicle controller 301 receives the manual braking signal, it can send a braking warning message to the central control instrument to remind the driver to pull the handbrake or step on the brake to achieve parking. Since the reaction of a person is slower than that of a machine, shortening the control path will not significantly improve the reaction speed of manual braking. Therefore, considering the simplicity of the hardware design, the warning message is output by the vehicle controller 301.

[0192] In addition, if the current braking method has a too long continuous braking time, the motor controller can stop the current braking method and send a manual braking signal to the vehicle controller 301 for replacement to avoid system risks. For example, when the braking force of the brake pedal is greater than the preset braking force, the electronic stability program 302 of the vehicle body triggers hydraulic braking. If the hydraulic braking time is too long, the motor controller sends a manual braking signal to the vehicle controller 301, exits the hydraulic braking, and reminds the driver to perform manual braking through the vehicle controller 301 to achieve parking.

[0193] In a possible implementation manner, taking Embodiment 3 as an example, the control device 1011 controls the gear controller 304 to output a gear control signal in response to the speed indicated by the speed signal being greater than or equal to the preset speed during the process of outputting the first control signal; wherein, the gear control signal is used to control the vehicle to run in the parking gear.

[0194] During the process of the motor controller controlling the speed of the drive motor 102 to decrease to achieve parking of the electric vehicle, if the speed of the drive motor 102 is greater than the preset speed, at this time the control device 1011 outputs a gear control signal to the gear controller 304, and the gear controller 304 controls the vehicle to run in the parking gear in response to the gear control signal.

[0195] For example, when the electric vehicle is on a slope, due to the large slope, the tendency of the electric vehicle to roll back is obvious. As Figure 8c shown, at time t0, the vehicle starts to roll back, and the motor speed indicated by the speed signal gradually increases;

[0196] At time t1, the braking signal indicates that the braking force is zero, the speed signal indicates that the speed is greater than zero and less than the preset speed, and the torque signal indicates that the torque is zero. The control device 1011 starts to output the first control signal, but the speed indicated by the speed signal exceeds the preset speed, indicating that the speed control of the control device 1011 cannot achieve vehicle slope holding;

[0197] At time t2, the control device 1011 outputs a gear control signal to the gear controller 304, the braking signal indicates that the braking force is greater than zero, the torque signal indicates that the torque is zero, and the speed signal indicates that the speed continuously decreases to zero.

[0198] Exemplarily, the preset speed of the motor is 100 revolutions per minute. The vehicle rolling back causes the motor speed to exceed 100 revolutions per minute. The control device 1011 responds to the speed indicated by the speed signal exceeding 100 revolutions per minute during the process of outputting the first control signal. At this time, the control device 1011 exits the speed control and outputs a gear control signal to the gear controller 304, and prevents the electric vehicle from rolling back by controlling the vehicle to run in the parking gear.

[0199] The motor controller provided by the embodiment of the present application realizes the function of outputting a gear control signal to the gear controller 304 to achieve vehicle parking in the case where speed control cannot achieve parking, thereby improving the safety of parking.

[0200] In addition, different from the traditional technology in which the vehicle controller 301 outputs a gear control signal, the gear control signal in the present application is output by the motor controller, which can shorten the control path, achieve rapid braking, and thus achieve rapid parking.

[0201] It should be noted that the embodiment of the present application can also use the vehicle speed as a judgment condition. For example, when the vehicle speed is greater than the preset vehicle speed during the process of the control device 1011 responding to output the first control signal, the control device 1011 outputs a gear control signal to the gear controller 304.

[0202] It can be understood that the above method of controlling the vehicle to be in a parked state is not only applicable to the vehicle condition where the motor speed is greater than or equal to the preset speed, but also applicable to other vehicle conditions where speed control cannot achieve parking.

[0203] III. Parking method assisted by the motor controller for driver indication

[0204] Embodiment 1

[0205] During the process of the control device 1011 responding to output the first control signal, when the torque indicated by the torque signal is greater than zero, the control device 1011 stops outputting the first control signal and outputs a second control signal.

[0206] It should be noted that the second control signal is used to control the inverter circuit 1012 to output a second drive current; the second drive current is used to adjust the output torque of the drive motor 102 to the torque indicated by the torque signal.

[0207] It can be understood that if the torque indicated by the torque signal is greater than or equal to the preset torque during the process of the control device 1011 outputting the first control signal, it indicates that the required torque of the vehicle is large. At this time, the speed control should be exited and the torque demand of the vehicle should be responded to avoid conflicting with the driver's intention;

[0208] For example, in the scenario where speed control realizes parking, as Figure 10 shown, at time t0, the control device 1011 outputs the first control signal, the torque indicated by the torque signal is zero, the braking force indicated by the braking signal is zero, under the speed control of the control device 1011, the speed indicated by the speed signal gradually decreases to zero. At time t1, the driver interrupts parking and starts driving, the torque indicated by the torque signal is greater than zero, the braking force indicated by the braking signal is zero, the control device 1011 stops outputting the first control signal and outputs a second control signal for torque control; the vehicle travels under torque control, and the speed indicated by the speed signal gradually increases.

[0209] Exemplarily, when the vehicle is in the parking state and the driver does not want to continue parking and wants to control the vehicle to move, the driver steps on the accelerator pedal, and the torque indicated by the torque signal is 200 N·m. At this time, the control device exits the speed control and controls the vehicle to move based on 200 N·m.

[0210] Alternatively, when the vehicle is on a slope and the driver wants to park the vehicle by means of torque control, the driver steps on the accelerator pedal, and the torque indicated by the torque signal is 200 N·m. At this time, the control device exits the speed control and controls the vehicle to move based on 200 N·m.

[0211] The motor controller provided by the embodiment of the present application accurately stops the speed control by judging the change of the torque signal, avoiding conflict with the driver's intention.

[0212] Embodiment 2

[0213] During the process that the control device 1011 responds to outputting the first control signal, when the braking force indicated by the braking signal is greater than zero, the control device 1011 is used to stop outputting the first control signal.

[0214] It can be understood that if, during the process that the control device 1011 outputs the first control signal, the braking force indicated by the braking signal is greater than zero, it means that the driver has operated such as stepping on the brake or pulling the handbrake. At this time, the speed control should be exited to avoid conflict with the driver's intention;

[0215] For example, the control device 1011 controls the motor speed to continuously decrease. As Figure 11 shown, at the moment t0, the control device 1011 outputs the first control signal, the torque indicated by the torque signal is zero, the braking force indicated by the braking signal is zero, and under the speed control of the control device 1011, the speed indicated by the speed signal gradually decreases;

[0216] At the moment t1, when the driver wants to stop the vehicle by braking and steps on the brake pedal, the braking force indicated by the braking signal is greater than zero, the torque indicated by the torque signal is equal to zero, the control device 1011 exits the motor speed control, that is, stops outputting the first control signal, and under the influence of the braking force, the speed signal continuously decreases to zero to achieve parking;

[0217] In addition, if the Autohold function of the vehicle is turned on, when the driver steps on the brake pedal, the ESP maintains the braking hydraulic pressure at the wheel end, and the vehicle can achieve automatic parking without operating such as shifting to the P gear, pulling the handbrake or activating the EPB.

[0218] For example, during the process of parking through speed control, the speed of the drive motor gradually decreases from 50 rpm to 20 rpm. At this time, the driver steps on the brake pedal, the control device exits the speed control, and ESP brakes through the hydraulic clamping brake caliper or brake disc of the hydraulic system, and the motor speed drops to zero to achieve parking.

[0219] The motor controller provided in the embodiment of the present application accurately stops speed control by judging changes in the braking signal, thereby avoiding conflicts with the driver's intentions.

[0220] Embodiment 3

[0221] In response to receiving a gear position signal during the process of outputting the first control signal, the control device 1011 is configured to stop outputting the first control signal. The gear position indicated by the gear position signal is the P gear.

[0222] It can be understood that if the gear position indicated by the gear position signal is P gear during the process of the control device 1011 outputting the first control signal, it means that the driver has engaged the P gear. At this time, the speed control should be exited to avoid conflict with the driver's intention.

[0223] For example, the control device 1011 controls the motor speed to continuously decrease, such as Figure 12 As shown, at time t0, the control device 1011 outputs the first control signal, the torque indicated by the torque signal is zero, the braking force indicated by the brake signal is zero, and under the speed control of the control device 1011, the speed indicated by the speed signal gradually decreases;

[0224] At time t1, the driver shifts the vehicle into P gear and activates EPB for parking. The brake caliper locks the motor to control vehicle braking. The braking force indicated by the brake signal is greater than zero, the torque indicated by the torque signal is zero, and the gear indicated by the gear signal is P gear. The control device 1011 exits the motor speed control, that is, stops outputting the first control signal, and parking is achieved according to the driver's wishes. The speed signal continues to drop to zero, and then the vehicle is stabilized and parked.

[0225] For example, in the process of parking by speed control, the speed of the drive motor gradually decreases from 50 rpm to 20 rpm. At this time, the driver presses the parking button, the control device exits the speed control, the EPB is activated, and the vehicle is braked by the motor against the brake disc. The motor speed drops to zero to achieve parking.

[0226] The motor controller provided in the embodiment of the present application accurately stops speed control by judging the change of the gear signal, thereby avoiding conflict with the driver's intention.

[0227] In summary, the present application discloses a motor controller, which can quickly and accurately park the vehicle in all scenarios; for example, the scenarios of releasing the accelerator pedal to park at low speed on a slope and parking on a slope for a long time. Secondly, the motor controller disclosed in the present application can also solve the problem of slow parking response speed by shortening the control path on this basis. Thirdly, for the scenario of long parking on a slope, the present application can determine the parking requirement without judging according to the slope of the ramp, so there is no need to additionally configure a slope sensor, saving hardware costs. Finally, the motor controller of the present application has low requirements for the vehicle. In most scenarios, the motor controller can achieve parking through speed control, and the vehicle does not need to be configured with other complex parking or braking functions. In addition, the motor controller can also assist other systems to achieve parking.

[0228] Based on the same inventive concept, as Figure 13a shown, an embodiment of the present application further provides a powertrain, and the powertrain 1300 includes a motor controller 101 and a drive motor 102 as Figure 1 shown. The implementation of the powertrain 1300 can refer to the relevant description of the above motor controller 101, and will not be elaborated here.

[0229] It should be noted that the above powertrain 1300 is a single-motor powertrain, and the present application can also be applied to two powertrains as Figure 13b shown. For ease of understanding, the two powertrains are distinguished as a first powertrain 1301 and a second powertrain 1302. The drive motor in the first powertrain 1301 is a first drive motor 13011, the control device is a first control device 13012, and the inverter circuit is a first inverter circuit 13013. The drive motor in the second powertrain 1302 is a second drive motor 13021, the control device is a second control device 13022, and the inverter circuit is a second inverter circuit 13023.

[0230] The first control device 13012 is configured to send a compensation signal to the second control device 13022 in response to the rotation speed of the first drive motor 13011 indicated by the rotation speed signal being greater than or equal to a preset rotation speed during the process of the first drive motor 13011 outputting a first control signal;

[0231] The second control device 13022 is configured to control the second drive motor 13021 to perform speed braking in response to the compensation signal.

[0232] For example, in scenarios where the ramp slope is large or the road surface is slippery, when the first drive motor 13011 has reached the maximum torque under the speed control of the first control device 13012 and the speed still cannot be controlled to zero and the vehicle cannot be braked to achieve parking, the first control device 13012 can send a compensation signal to the second control device 13022 to request the second drive motor 13021 to assist in speed braking.

[0233] It is understandable that if the rotational speed control of two powertrains fails to achieve parking, the rotational speed control can be exited by referring to the relevant embodiments of the above single motor controller, and other control methods can be assisted to achieve parking;

[0234] Similarly, if the driver indicates a parking method during the rotational speed control of two powertrains, the rotational speed control can be exited by referring to the functions of the above single motor controller to assist the parking method indicated by the driver.

[0235] Based on the same inventive concept, an embodiment of the present application also provides a vehicle, as Figure 14 shown, the vehicle includes a power battery 1401 and a powertrain 1402; wherein, the power battery 1401 is used to supply power to the inverter circuit of the powertrain 1402, and the specific implementation manner can refer to Figure 2 the corresponding description.

[0236] Based on the same inventive concept, an embodiment of the present application also provides a parking method, which is applied to the motor controller as Figure 1 shown. The implementation of the parking method can refer to the embodiments of the above motor controller, and the repeated parts will not be described again. As Figure 15 shown, the method includes:

[0237] Step 1501, the control device receives a rotational speed signal of the drive motor indicating that the rotational speed is greater than zero and less than a preset rotational speed.

[0238] Step 1502, the control device determines whether the braking force of the vehicle indicated by the braking signal is greater than zero. If so, step 1503 is executed; otherwise, step 1504 is executed.

[0239] Step 1503, the control device enters the hydraulic control mode or the electronic parking control mode.

[0240] For example, when the driver steps on the brake pedal, the control device outputs a hydraulic control signal so that the hydraulic system controls to clamp the brake caliper or the brake disc to achieve parking; or when the driver pulls the parking brake, the control device outputs an electronic parking signal to hold the brake disc by the motor to achieve parking.

[0241] Step 1504, the control device determines whether the torque indicated by the torque signal is greater than zero. If so, step 1506 is executed; otherwise, step 1505 is executed.

[0242] Step 1505, the control device enters the rotational speed control mode, and steps 1502 and 1504 are executed during the rotational speed control:

[0243] During the process of speed control, if the control device determines that the motor stall duration is greater than the fourth preset duration, or the control device determines that the speed indicated by the speed signal is greater than the preset speed, or the control device determines that the vehicle speed is greater than the preset vehicle speed, or the control device determines that the amplitude of the first drive current is greater than the preset amplitude, or the control device determines that the duration of the first drive current is greater than the third preset duration, then step 1507 is executed;

[0244] During the process of speed control, if the gear signal received by the control device indicates the parking gear, then step 1508 is executed;

[0245] Step 1506, the control device enters the torque control mode.

[0246] Step 1507, the control device exits the speed control and requests other systems to achieve parking.

[0247] The following takes the control device determining that the speed indicated by the speed signal is greater than the preset speed as an example for introduction:

[0248] In a possible implementation, the control device is configured to output a braking request signal to the brake controller in response to the speed indicated by the speed signal being greater than or equal to the preset speed during the process of outputting the first control signal.

[0249] Exemplarily, the preset speed of the motor is 100 revolutions per minute. If the control device determines that the speed indicated by the speed signal is greater than or equal to 100 revolutions per minute during the process of outputting the first control signal, then at this time, the control device exits the speed control and enters the hydraulic control mode or the electronic parking mode to prevent the electric vehicle from rolling.

[0250] In a possible implementation, in response to the speed indicated by the speed signal being greater than or equal to the preset speed during the process of outputting the first control signal, a gear control signal is output to the gear controller; wherein, the gear control signal is used to control the vehicle to operate in the parking gear.

[0251] Exemplarily, the preset speed of the motor is 100 revolutions per minute. If the control device 1011 determines that the speed indicated by the speed signal is greater than or equal to 100 revolutions per minute during the process of outputting the first control signal, then at this time, the control device 1011 exits the speed control and outputs a gear control signal to the gear controller to prevent the electric vehicle from rolling by controlling the vehicle to operate in the parking gear.

[0252] In a possible implementation, the control device is configured to output a manual braking signal in response to the speed indicated by the speed signal being greater than or equal to the preset speed during the process of speed control and the vehicle condition where other speed braking cannot achieve parking, so as to remind the driver to perform manual braking to achieve parking.

[0253] Step 1508, the control device exits the speed control and controls the gear controller to operate in the parking gear.

[0254] Obviously, those skilled in the art can make various modifications and variations to this application without departing from the scope of protection of this application. Thus, if these modifications and variations of this application fall within the scope of the claims of this application and their equivalent technologies, then this application is also intended to include these modifications and variations.

Claims

1. A motor controller for implementing vehicle rollback control, characterized in that, The motor controller includes a control device and an inverter circuit; The control device is configured to receive a braking signal, a torque signal, and a rotational speed signal from a resolver of the drive motor, wherein the braking signal is used to indicate the braking force of the vehicle, the rotational speed signal is used to indicate the rotational speed of the drive motor, the torque signal is used to indicate the torque of the drive motor, and the inverter circuit includes a multi-phase bridge arm, and the midpoint of the bridge arm of the multi-phase bridge arm is used to connect the multi-phase windings of the drive motor; The control device is configured to: At a first moment during the vehicle traveling on a slope, when the braking signal indicates that the braking force is less than a preset braking force, the torque signal indicates that the torque is less than a preset torque, the rotational speed signal indicates that the rotational speed is greater than zero and less than a preset rotational speed, and the rotational speed signal indicates that the rotational speed is decreasing, output a first control signal to control the inverter circuit to output a first drive current to reduce the rotational speed of the drive motor; At a second moment after the first moment, when the braking signal indicates that the braking force is zero and the torque signal indicates that the torque is greater than the preset torque, stop outputting the first control signal and output a second control signal to control the drive motor to accelerate.

2. The motor controller according to claim 1, wherein The control device is configured to sequentially receive a first braking signal and a second braking signal, wherein the braking force indicated by the first braking signal is greater than a preset braking force, and the braking force indicated by the second braking signal is zero. The control device is configured to: In response to the duration of the second braking signal being greater than a first preset duration and the torque indicated by the torque signal being zero within the first preset duration, and the rotational speed of the motor indicated by the rotational speed signal being greater than zero and less than a preset rotational speed within the first preset duration, output a first control signal.

3. The motor controller according to claim 1 or 2, characterized in that, The control device is configured to: In response to the rotational speed indicated by the rotational speed signal being greater than or equal to the preset rotational speed during the process of outputting the first control signal, stop outputting the first control signal.

4. The motor controller according to any one of claims 1-3, characterized in that The control device is configured to: In response to the torque indicated by the torque signal being greater than zero during the process of outputting the first control signal, stop outputting the first control signal and output a second control signal; wherein the second control signal is used to control the inverter circuit to output a second drive current; and the second drive current is used to adjust the output torque of the drive motor to the torque indicated by the torque signal.

5. The motor controller according to any one of claims 1-4, characterized in that, The control device is configured to: In response to the braking force indicated by the braking signal being greater than or equal to the preset braking force during the process of outputting the first control signal, stop outputting the first control signal.

6. The motor controller according to any one of claims 1-5, characterized in that, The control device is configured to: In response to receiving a first gear signal during the process of outputting the first control signal, stop outputting the first control signal; wherein the gear indicated by the first gear signal is the parking gear.

7. The motor controller according to any one of claims 1-6, characterized in that, The control device is configured to: In response to the duration of the inverter circuit outputting the first drive current being greater than a third preset duration, stop outputting the first control signal.

8. The motor controller according to any one of claims 1-7, characterized in that, The control device is configured to: During the process of outputting the first control signal, if the duration when the rotational speed indicated by the rotational speed signal is zero and the torque indicated by the torque signal is not zero is greater than a fourth preset duration, stop outputting the first control signal.

9. The motor controller according to any one of claims 1-8, characterized in that, The control device is configured to: In response to the amplitude of the first drive current being greater than a preset amplitude, stop outputting the first control signal.

10. The motor controller according to any one of claims 1-9, characterized in that, The control device is configured to: During the process of outputting the first control signal, if the rotational speed indicated by the rotational speed signal is greater than or equal to the preset rotational speed, output a braking request signal to the braking controller, and the braking request signal is used to control the braking system to output braking force.

11. A powertrain, characterized in that, The powertrain includes the motor controller and the drive motor as described in any one of claims 1-10, the drive motor is provided with a motor speed sensor, and the motor controller is configured to receive the motor speed signal of the motor speed sensor.

12. A vehicle, characterized in that, The vehicle includes a power battery and the powertrain as described in claim 11; the power battery is used to supply power to the powertrain.

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