WO2021197441A1

WO2021197441A1 - Energy recovery control method and system, and vehicle

Info

Publication number: WO2021197441A1
Application number: PCT/CN2021/084998
Authority: WO
Inventors: 胡志敏; 刘宝; 侯文涛; 高天; 田福刚; 陈玉封; 刁红宾; 郑飞
Original assignee: 长城汽车股份有限公司
Priority date: 2020-04-02
Filing date: 2021-04-01
Publication date: 2021-10-07
Also published as: CN113492682B; CN113492682A

Abstract

An energy recovery control method comprises: during an energy recovery process performed by a motor, acquiring a current vehicle velocity and a current wheel speed of a vehicle, and determining a wheel slip rate according to the current vehicle velocity and the current wheel speed (S100); and adjusting, according to the wheel slip rate, an actual energy recovery torque of the motor (S200). Also disclosed are an energy recovery control system, a vehicle, a computer processing apparatus, a computer program, and a computer readable medium. In the method, a wheel slip rate is taken into consideration in a process of controlling a motor to perform energy recovery, such that an actual energy recovery torque of the motor can be dynamically adjusted according to the wheel slip rate, thereby preventing a wheel from locking due to an excessively large energy recovery torque, and ensuring brake performance of the vehicle.

Description

Energy recovery control method, system and vehicle

Cross-references to related applications

This disclosure requires the priority of a Chinese patent application filed with the Chinese Patent Office on April 2, 2020, with an application number of 202010256836.3, titled "An Energy Recovery Control Method, System and Vehicle", the entire content of which is incorporated herein by reference In the open.

Technical field

The present disclosure relates to the field of automobile technology, and in particular to an energy recovery control method, system and vehicle.

Background technique

At present, with the increasingly serious global environmental problems, new energy vehicles are developing rapidly.

Compared with traditional cars, electric motors are added to new energy vehicles. The motor can be used to drive the vehicle, or when the vehicle is decelerating, by turning on the energy recovery function, the motor generates electricity to generate torque in the opposite direction to slow the vehicle, and at the same time, it can recover the kinetic energy of the vehicle and extend the driving range of the vehicle. .

At this stage, most vehicles, including new energy vehicles, are equipped with anti-lock braking system (ABS), which can prevent the vehicle from braking by slightly reducing the pressure of the master cylinder when the vehicle is braking. The wheels are locked to ensure the braking performance of the vehicle.

However, when new energy vehicles perform energy recovery, because there is no braking pressure in the brake master cylinder, if the vehicle is driving on a smoother road, even if the vehicle is about to lock up and slip, the ABS will not be able to pass. Reduce the brake master cylinder pressure to avoid the occurrence of vehicle slippage, which in turn will affect the driving safety of the vehicle.

Public content

In view of this, the present disclosure aims to provide an energy recovery control method, system, and vehicle to solve the problem of wheel lock and drag when the existing new energy sources perform energy recovery on wet and slippery roads, which affects the driving safety of the vehicle. problem.

In order to achieve the above objective, the technical solution of the present disclosure is achieved as follows:

An energy recovery control method, applied to a vehicle, the vehicle including a motor, wherein the method includes:

In the process of energy recovery by the motor, acquiring the current vehicle speed and current wheel speed of the vehicle, and determining the wheel slip rate according to the current vehicle speed and the current wheel speed;

According to the wheel slip rate, the actual energy recovery torque of the motor is adjusted.

Further, in the method, the vehicle is preset with a recovery torque adjustment mechanism; the adjusting the actual energy recovery torque of the motor according to the wheel slip rate includes:

If the wheel slip rate is greater than or equal to the first slip rate threshold, controlling the recovery torque adjustment mechanism to be in an active state;

If the wheel slip rate is less than or equal to the second slip rate threshold, control the recovery torque adjustment mechanism to be in a closed state; wherein, the second slip rate threshold is less than the first slip rate threshold;

If the wheel slip rate is greater than the second slip rate threshold and less than the first slip rate threshold, controlling the recovery torque adjustment mechanism to maintain the current state;

When the recovery torque adjustment mechanism is in an active state, according to a preset rule, the actual energy recovery torque of the motor is reduced.

Further, in the method, the current vehicle speed and current wheel speed of the vehicle are acquired during the energy recovery process of the motor, and the wheel slip rate is determined according to the current vehicle speed and the current wheel speed Before, it also included:

Obtain target vehicle status information;

If it is determined that energy recovery is required according to the target vehicle status information, then determine the basic energy recovery torque according to the target vehicle status information;

According to the basic energy recovery torque, the motor is triggered to perform energy recovery.

Further, in the method, the target vehicle state information includes the current vehicle speed, accelerator pedal opening, and brake pedal opening of the vehicle.

Further, in the method, if it is determined that energy recovery is required according to the target vehicle status information, then determining the basic energy recovery torque according to the target vehicle status information includes:

If it is detected that the brake pedal opening degree is greater than or equal to the first opening degree threshold, determining the basic energy recovery torque according to the brake pedal opening degree;

If it is monitored that the current vehicle speed is greater than or equal to the first vehicle speed threshold, and the brake pedal opening degree and the accelerator pedal opening degree are both 0, the basic energy recovery torque is determined according to the current vehicle speed.

Further, in the method, the vehicle stores a first correspondence relationship between a brake pedal opening degree and energy recovery torque, and a second correspondence relationship between vehicle speed and energy recovery torque;

If it is determined that energy recovery is required according to the target vehicle state information, then determining the basic energy recovery torque according to the target vehicle state information includes:

If the brake pedal opening degree is greater than or equal to the first opening degree threshold, determining the basic energy recovery torque according to the brake pedal opening degree and the first corresponding relationship;

If the current vehicle speed is greater than or equal to the first vehicle speed threshold, and the brake pedal opening degree and the accelerator pedal opening degree are both 0, then the current vehicle speed and the second corresponding relationship are used to determine The basic energy recovery torque.

Further, in the method, in the first corresponding relationship, the energy recovery torque increases as the opening of the brake pedal increases;

In the second correspondence, when the vehicle speed is less than or equal to the second vehicle speed threshold, the energy recovery torque increases as the vehicle speed increases, and when the vehicle speed is greater than or equal to the second vehicle speed threshold , The energy recovery torque decreases as the vehicle speed increases; wherein the second vehicle speed threshold value is greater than the first vehicle speed threshold value, and the second vehicle speed threshold value is less than or equal to the turning point vehicle speed value, and the turning point vehicle speed value In the external characteristic curve of the motor, the vehicle speed value when the motor changes from a constant torque state to a constant power state.

Another objective of the embodiments of the present disclosure is to provide an energy recovery control system, which is applied to a vehicle, the vehicle includes a motor, and the system includes:

The first determining module, during the energy recovery process of the motor, obtains the current vehicle speed and the current wheel speed of the vehicle, and determines the wheel slip rate according to the current vehicle speed and the current wheel speed;

The control module is used to adjust the actual energy recovery torque of the motor according to the wheel slip rate.

Further, in the system, the vehicle is preset with a recovery torque adjustment mechanism; the control module includes:

The first control unit is configured to control the recovery torque adjustment mechanism to be in an active state if the wheel slip rate is greater than or equal to a first slip rate threshold;

The second control unit is configured to control the recovery torque adjustment mechanism to be in a closed state if the wheel slip rate is less than or equal to a second slip rate threshold; wherein, the second slip rate threshold is less than the first slip rate threshold. A slip rate threshold;

The third control unit is configured to control the recovery torque adjustment mechanism to maintain the current state if the wheel slip rate is greater than the second slip rate threshold and less than the first slip rate threshold;

The fourth control unit is configured to reduce the actual energy recovery torque of the motor according to a preset rule when the recovery torque adjustment mechanism is in an active state.

Further, the system further includes:

The acquisition module is used to acquire the status information of the target vehicle;

The second determination module is configured to determine the basic energy recovery torque according to the target vehicle state information if it is determined that energy recovery is required according to the target vehicle state information;

The trigger module is used to trigger the motor to perform energy recovery according to the basic energy recovery torque.

Further, in the system, the target vehicle state information includes the current vehicle speed, accelerator pedal opening, and brake pedal opening of the vehicle.

Further, in the system, the second determining module includes:

The first determining unit is configured to determine the basic energy recovery torque according to the brake pedal opening degree if it is detected that the brake pedal opening degree is greater than or equal to the first opening degree threshold;

The second determining unit is configured to determine the basic energy according to the current vehicle speed if it is monitored that the current vehicle speed is greater than or equal to the first vehicle speed threshold, and the brake pedal opening degree and the accelerator pedal opening degree are both 0 Recover the torque.

Further, in the system, the vehicle stores a first correspondence relationship between a brake pedal opening degree and energy recovery torque, and a second correspondence relationship between vehicle speed and energy recovery torque;

The first determining unit is specifically configured to determine the basis according to the brake pedal opening degree and the first correspondence relationship if the brake pedal opening degree is greater than or equal to the first opening degree threshold. Energy recovery torque;

The second determining unit is specifically configured to: if the current vehicle speed is greater than or equal to the first vehicle speed threshold, and the brake pedal opening degree and the accelerator pedal opening degree are both 0, then according to the current vehicle speed and The second corresponding relationship determines the basic energy recovery torque.

Further, in the system, in the first corresponding relationship, the energy recovery torque increases as the opening of the brake pedal increases;

In the second correspondence, when the vehicle speed is less than or equal to the second vehicle speed threshold, the energy recovery torque increases as the vehicle speed increases, and when the vehicle speed is greater than or equal to the second vehicle speed Threshold value, the energy recovery torque decreases as the vehicle speed increases; wherein the second vehicle speed threshold value is greater than the first vehicle speed threshold value, and the second vehicle speed threshold value is less than or equal to the turning point vehicle speed value, and the turning point The vehicle speed value is the vehicle speed value when the motor is changed from a constant torque state to a constant power state in the external characteristic curve of the motor.

Another object of the present disclosure is to provide a vehicle including an electric motor, wherein the vehicle further includes the energy recovery control system as described above.

Compared with the prior art, the energy recovery control method, system and vehicle described in the present disclosure have the following advantages:

During the energy recovery process of the generator, the current vehicle speed and the current wheel speed of the vehicle are obtained, and the wheel slip rate is determined according to the current vehicle speed and the current wheel speed; and then the wheel slip rate is adjusted according to the wheel slip rate. State the actual energy recovery torque of the motor. Because in the process of controlling the motor for energy recovery, the wheel slip rate is also considered, and the actual energy recovery torque of the motor can be dynamically adjusted according to the wheel slip rate, which can avoid the wheel lock due to excessive energy recovery torque, and ensure The braking performance of the vehicle is improved, and the driving safety of the vehicle is improved, thereby solving the problem that the wheel lock and drag phenomenon are prone to occur when the existing new energy is used for energy recovery on wet and slippery roads, which affects the driving safety of the vehicle.

The above description is only an overview of the technical solutions of the present disclosure. In order to understand the technical means of the present disclosure more clearly, they can be implemented in accordance with the content of the specification, and in order to make the above and other objectives, features and advantages of the present disclosure more obvious and easy to understand. In the following, specific embodiments of the present disclosure are specifically cited.

Description of the drawings

In order to more clearly describe the technical solutions in the embodiments of the present disclosure or related technologies, the following will briefly introduce the drawings that need to be used in the description of the embodiments or related technologies. Obviously, the drawings in the following description are of the present invention. For some of the disclosed embodiments, those of ordinary skill in the art can obtain other drawings based on these drawings without creative work.

FIG. 1 is a schematic flow chart of the energy recovery control method proposed by an embodiment of the disclosure;

2 is a schematic diagram of a first correspondence between energy recovery torque and brake pedal opening in an embodiment of the disclosure;

3 is a schematic diagram of a second correspondence between energy recovery torque and vehicle speed in an embodiment of the disclosure;

Figure 4 is a schematic flow chart of the energy recovery control method proposed in a preferred embodiment of the present disclosure

FIG. 5 is an execution flow chart of the energy recovery control method proposed by an embodiment of the disclosure;

Fig. 6 is a control principle diagram of the energy recovery control method proposed by an embodiment of the disclosure;

FIG. 7 is a schematic structural diagram of an energy recovery control system proposed by an embodiment of the disclosure;

FIG. 8 schematically shows a block diagram of a computing processing device for executing the method according to the present disclosure; and

Fig. 9 schematically shows a storage unit for holding or carrying program codes for implementing the method according to the present disclosure.

Specific embodiment

In order to make the objectives, technical solutions, and advantages of the embodiments of the present disclosure clearer, the technical solutions in the embodiments of the present disclosure will be described clearly and completely in conjunction with the accompanying drawings in the embodiments of the present disclosure. Obviously, the described embodiments These are a part of the embodiments of the present disclosure, but not all of the embodiments. Based on the embodiments in the present disclosure, all other embodiments obtained by those of ordinary skill in the art without creative work shall fall within the protection scope of the present disclosure.

Hereinafter, embodiments of the present application will be described in more detail with reference to the accompanying drawings. Although the embodiments of the present application are shown in the drawings, it should be understood that the present application can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided to enable a more thorough understanding of this application and to fully convey the scope of this application to those skilled in the art.

It should be noted that the embodiments in the present disclosure and the features in the embodiments can be combined with each other if there is no conflict.

Hereinafter, the present disclosure will be described in detail with reference to the drawings and in conjunction with the embodiments.

Please refer to FIG. 1, which shows a schematic flowchart of an energy recovery control method provided by an embodiment of the present disclosure. The energy recovery control method provided by the embodiment of the present disclosure is applied to a vehicle, and the vehicle includes a motor. Including steps S100-S200.

The energy recovery control method provided by the embodiments of the present disclosure is applicable to a new energy vehicle, which includes a motor and a battery electrically connected to the motor; wherein the motor can be driven by the battery to rotate to drive the vehicle to travel; When the vehicle needs to decelerate or brake, the motor can also charge the battery after converting part of the kinetic energy of the vehicle into electrical energy through magnetoelectricity, so as to store the converted electrical energy in the battery, thereby achieving the purpose of energy recovery; The above-mentioned battery is not only used to supply power to the above-mentioned motor and other electric components of the vehicle, but also used to store the electric energy generated when the motor performs energy recovery.

In practical applications, the above-mentioned motor includes a driving motor and a generator mechanically connected to the above-mentioned driving motor, and both the above-mentioned driving motor and the generator are electrically connected to the above-mentioned battery.

Step S100: In the process of energy recovery of the motor, the current vehicle speed and the current wheel speed of the vehicle are obtained, and the wheel slip rate is determined according to the current vehicle speed and the current wheel speed.

In the above step S100, the above-mentioned energy recovery process refers to the use of a motor to convert a part of the kinetic energy during braking or deceleration of the vehicle into electrical energy through magnetoelectricity, which is stored in the power battery, and at the same time, a certain braking resistance is generated on the motor. , In order to make the vehicle decelerate and brake the process. The direction of the braking resistance is opposite to the rotation direction of the motor, so the vehicle can be braked and decelerated. In practical applications, the aforementioned braking resistance is specifically realized by braking torque, which is also energy recovery torque. By adjusting the magnetic field strength during magnetoelectric conversion, the magnitude of the aforementioned energy recovery torque can be adjusted, that is, different Intensive deceleration and braking effect.

In the above step S100, whether the wheel lock phenomenon occurs can be reflected by the relationship between the vehicle speed and the wheel speed. Therefore, it is necessary to obtain the current vehicle speed and the current wheel speed of the vehicle. Among them, when the wheel is not locked, the vehicle speed and wheel speed should be equal; and if the vehicle speed is greater than the wheel speed, it means that the phenomenon of wheel drag and lock has occurred. Specifically, the relationship between vehicle speed and wheel speed can be expressed by wheel slip rate. Specifically, the aforementioned wheel slip rate can be calculated according to the following formula:

Among them, s is the wheel slip rate, v is the vehicle speed, ω is the wheel speed, and r is the wheel rolling radius.

Step S200: Adjust the actual energy recovery torque of the motor according to the wheel slip rate.

In the above step S200, because the magnitude of the wheel slip rate reflects the relationship between the current vehicle speed and the current wheel speed of the vehicle, it can be determined whether the wheel has dragged or locked according to the above wheel slip rate, and then When the wheels are about to lock up and slip, the actual energy recovery torque of the motor during energy recovery can be adjusted to adjust the braking resistance generated on the motor, that is, to adjust the strength of the vehicle to decelerate and brake. Among them, when the motor is recovering energy, the wheel locks up, indicating that the braking resistance generated by the energy recovery torque on the motor exceeds the friction provided by the surface of the wheel; and the actual energy recovery when the motor is adjusted for energy recovery Torque makes the braking resistance generated on the motor less than or equal to the friction provided by the surface of the wheel, thereby improving the situation of wheel slip due to excessive energy recovery torque.

Compared with the prior art, the energy recovery control method described in the present disclosure has the following advantages:

Optionally, in an implementation manner, the energy recovery control method provided by the embodiment of the present disclosure further includes steps S101 to S103 before the above step S100.

Step S101: Obtain target vehicle status information.

In the above step S101, the target vehicle state information is state information used to determine whether the vehicle is required for energy recovery.

Optionally, the aforementioned target vehicle state information may include current vehicle speed, accelerator pedal opening, and brake pedal opening. Among them, the accelerator pedal opening degree reflects whether the driver needs the motor to continue to drive the vehicle. If it is determined based on the accelerator pedal opening degree that the driver does not need the motor to continue driving the vehicle, the motor can be controlled for energy recovery; and the speed of the vehicle reflects the current kinetic energy of the vehicle It also reflects the amount of torque that can be used for energy recovery, so it can be determined whether it is necessary to control the motor for energy recovery, so the current speed of the vehicle needs to be obtained; the brake pedal opening reflects the driver's deceleration and braking According to the demand, if it is determined that the driver needs to decelerate and brake the vehicle according to the opening of the brake pedal, the motor can be controlled for energy recovery.

Step S102: If it is determined that energy recovery is required according to the target vehicle state information, then determine the basic energy recovery torque according to the target vehicle state information.

In the foregoing step S102, the foregoing basic energy recovery torque is the initial torque of the motor for energy recovery. In step S102, if it is determined that there is an energy recovery demand based on the target vehicle status information, the target vehicle status information is used to determine the initial torque of the motor for energy recovery, so that the initial torque triggers the motor to turn on for energy recovery.

Step S103: According to the basic energy recovery torque, trigger the motor to perform energy recovery.

In the above step S103, according to the basic energy recovery torque strength determined in the above step S102, the motor is triggered to cut the magnetic induction line to perform energy recovery, and the kinetic energy of the vehicle is converted into electric energy and stored in the battery.

In this embodiment, the target vehicle state information is monitored to determine whether energy recovery is needed, and when energy recovery is required, the target vehicle state information determines the basic energy recovery torque, and triggers the motor to perform energy recovery based on the basic energy recovery torque.

Optionally, in a specific implementation manner, the above step S102 includes steps S201 to S202.

Step S201: If it is detected that the brake pedal opening degree is greater than or equal to the first opening degree threshold, the basic energy recovery torque is determined according to the brake pedal opening degree.

In the above step S201, the first opening threshold is the brake pedal opening threshold for determining whether energy recovery is required. When the brake pedal opening is greater than or equal to the first opening threshold, it is determined that energy recovery is required, and at the same time Because the opening degree of the brake pedal reflects the intensity of the driver's need to control the deceleration and braking of the vehicle, the basic recovery torque used to trigger the motor for energy recovery can be determined according to the opening degree of the brake pedal.

Step S202: If it is monitored that the current vehicle speed is greater than or equal to the first vehicle speed threshold, and the brake pedal opening degree and the accelerator pedal opening degree are both 0, determine the basic energy recovery torque according to the current vehicle speed.

In the above step S202, the first vehicle speed threshold is the vehicle speed threshold for determining whether energy recovery is required. When the current vehicle speed is greater than or equal to the first vehicle speed threshold, if the driver does not step on the brake pedal and releases the accelerator pedal, This means that the driver does not need the motor to continue to drive the vehicle, so it is determined that energy recovery is required. At the same time, the size of the basic recovery torque used to trigger the motor to perform energy recovery can be determined according to the current vehicle speed.

In the above specific embodiment, the driver’s driving demand is determined by monitoring the brake pedal opening, the current vehicle speed and the accelerator pedal opening, thereby determining whether energy recovery is required, and when energy recovery is required, according to the system The opening degree of the movable pedal determines the basic energy recovery torque, or determines the basic energy recovery torque according to the current vehicle speed, so as to trigger the electric motor to perform energy recovery.

Optionally, in a more specific embodiment, the vehicle stores a first correspondence between the brake pedal opening and the energy recovery torque, and a second correspondence between the vehicle speed and the energy recovery torque;

The foregoing step S201 specifically includes:

The above step S202 specifically includes: if the current vehicle speed is greater than or equal to the first vehicle speed threshold, and the brake pedal opening degree and the accelerator pedal opening degree are both 0, then according to the current vehicle speed and the The second corresponding relationship determines the basic energy recovery torque.

In this embodiment, by storing the first corresponding relationship between the brake pedal opening and the energy recovery torque in the vehicle, it is possible to monitor that the brake pedal opening is greater than or equal to the first opening threshold according to the brake The pedal opening and the first corresponding relationship can quickly determine the basic energy recovery torque; by storing the second corresponding relationship between the vehicle speed and the energy recovery torque, it can be monitored that the current vehicle speed is greater than or equal to the first vehicle speed threshold , And when the opening degree of the brake pedal and the opening degree of the accelerator pedal are both 0, the basic energy recovery torque is quickly determined according to the current vehicle speed and the second corresponding relationship.

Optionally, in the foregoing first corresponding relationship, the energy recovery torque increases as the opening degree of the brake pedal increases. Because the greater the opening of the brake pedal, the greater the braking intensity required by the driver. Therefore, as the brake pedal is stepped deeper, the corresponding energy recovery torque is greater, which can match the driving habits and satisfy the driver. Actual demand.

Specifically, please refer to FIG. 2, which shows a schematic diagram of a first corresponding relationship between the energy recovery torque and the opening of the brake pedal. In Figure 2, M represents the first opening threshold; N represents the second opening threshold, which is the brake pedal opening corresponding to when the motor reaches the maximum energy recovery torque.

As shown in Figure 2, when the brake pedal opening is less than the first opening threshold, the corresponding energy recovery torque is 0, that is, the brake pedal is in the idle stroke stage; after the idle stroke, as the brake pedal opens The energy recovery torque gradually increases as the motor’s maximum recovery capacity is reached. With the increase of the brake pedal opening, the recovery torque value remains unchanged. At this time, if the recovery torque cannot meet the user’s braking demand , The mechanical brake intervenes and supplements the braking force to meet the braking needs of users.

Optionally, in the second correspondence, when the vehicle speed is less than or equal to a second vehicle speed threshold, the energy recovery torque increases as the vehicle speed increases, and when the vehicle speed is greater than or equal to the second vehicle speed Threshold value, the energy recovery torque decreases as the vehicle speed increases; wherein the second vehicle speed threshold value is greater than the first vehicle speed threshold value, and the second vehicle speed threshold value is less than or equal to the turning point vehicle speed value, and the turning point The vehicle speed value is the vehicle speed value when the motor changes from a constant torque state to a constant power state in the external characteristic curve of the motor.

In this embodiment, the above-mentioned external characteristic curve represents the corresponding relationship between the output power and output torque of the motor and the vehicle speed. According to the external characteristic curve, the actual output power and actual output torque of the motor can be determined at different vehicle speeds. The actual output power and actual output torque are the maximum energy recovery available power and maximum energy recovery of the motor for energy recovery. Available torque. Among them, in the above external characteristic curve, as the vehicle speed increases, that is, as the motor speed increases, the output power of the motor gradually increases, while its output torque remains unchanged, and the drive motor is in a constant torque state at this time; The vehicle speed when the vehicle speed increases until the output power of the motor reaches its maximum power value is the second vehicle speed threshold; after that, as the vehicle speed continues to increase, the output torque of the motor begins to decrease, and its output power remains at the maximum power value. , The drive motor is in a constant power state at this time.

In practical applications, the external characteristic curve needs to be set through experiments in advance. Because of the difference in performance between vehicles, different vehicles need to be configured with different external characteristic curves.

In this embodiment, by setting when the vehicle speed is less than or equal to the second vehicle speed threshold, the energy recovery torque increases as the vehicle speed increases, and when the vehicle speed is greater than or equal to the second vehicle speed threshold, the energy The recovery torque decreases with the increase of the vehicle speed, which can match the change of the maximum energy recovery available torque of the motor, and set the corresponding basic energy recovery torque for the motor to more fully recover the kinetic energy of the vehicle.

Specifically, please refer to FIG. 3, which shows a schematic diagram of the second correspondence between the energy recovery torque and the vehicle speed. In Figure 3, P represents the first vehicle speed threshold; Q represents the second vehicle speed threshold.

As shown in Figure 3, when the driver is stepping on the brake pedal and accelerator pedal, starting from the vehicle speed being greater than the second vehicle speed threshold, as the vehicle speed decreases, the energy recovery torque gradually increases. When the vehicle speed drops below the second threshold value The vehicle begins to gradually decrease; when the vehicle speed decreases to the first vehicle speed threshold, the energy recovery torque is set to 0, that is, the motor is controlled to exit energy recovery.

Optionally, in one embodiment, the vehicle is preset with a recovery torque adjustment mechanism; the above step S200 includes steps S211 to S214.

Step S211: If the wheel slip rate is greater than or equal to the first slip rate threshold, control the recovery torque adjustment mechanism to be in an active state.

In the above step S211, because the difference between the vehicle speed and the wheel speed has reached a certain condition, it indicates that the wheels have slipped or locked, that is, the energy recovery torque needs to be adjusted, so it is necessary to set a wheel slip rate. Used to determine the threshold, that is, the above-mentioned first slip rate threshold. As long as the wheel slip rate is greater than or equal to the first slip rate threshold, it indicates that the torque of the motor for energy recovery needs to be adjusted. Therefore, the recovery torque adjustment mechanism is activated to make the recovery The torque adjustment mechanism is active.

Step S212: If the wheel slip rate is less than or equal to a second slip rate threshold, control the recovery torque adjustment mechanism to be in a closed state; wherein the second slip rate threshold is less than the first slip rate Threshold.

In the above step S212, the second slip rate threshold is the slip rate threshold used to determine the stop of adjusting the motor for energy recovery torque adjustment. As long as the wheel slip rate is less than or equal to the second slip rate threshold, it means that there is no need to The energy recovery torque of the motor is adjusted according to the wheel slip rate, and thus the recovery torque adjustment mechanism is closed, so that the recovery torque adjustment mechanism is in a closed state. Wherein, if the second slip rate threshold is set to be less than the first slip rate threshold, a slip rate buffer zone can be set between the first slip rate threshold and the second slip rate threshold, so that the wheel slip rate is at the first slip rate. When the slip rate is near the threshold, there will be no frequent switching of the state of the recovery torque adjustment mechanism due to the slight swing of the wheel slip rate in the vicinity of the first slip rate threshold.

Step S213: If the wheel slip rate is greater than the second slip rate threshold and less than the first slip rate threshold, control the recovery torque adjustment mechanism to maintain the current state.

In the above step S213, that is, when the wheel slip rate is between the second slip rate threshold and the first slip rate threshold, it indicates that the wheel slip rate state that activates the recovery torque adjustment mechanism in the off state has not been reached, It also fails to reach the wheel slip rate state where the activated recovery torque adjustment mechanism is turned off, so the original state of the recovery torque adjustment mechanism is not changed, that is, the recovery torque adjustment mechanism is controlled to maintain its current state.

It can be seen from steps S211 to S213 that the embodiment of the present disclosure reserves a certain slip rate buffer zone for the activation of the recovery torque adjustment mechanism, and the slip rate buffer zone is the first slip rate threshold and the second slip rate threshold. The difference between. If the wheel slip rate meets the higher entry condition of greater than the first slip rate threshold, the recovery torque adjustment mechanism is activated at this time, and in the activated state, the current wheel slip rate is allowed to be lower than the first slip rate As long as the entry condition of the rate threshold is not lower than the exit condition of the second slip rate threshold, the recovery torque adjustment mechanism remains active.

Similarly, if the wheel slip rate meets the lower exit condition of less than the second slip rate threshold, the recovery torque adjustment mechanism is in the off state at this time, and in the off state, the wheel slip rate is allowed to be higher than the second slip rate threshold. As long as the exit condition of the preset rate of change is not higher than the exit condition of the first preset rate of change, the recovery torque adjustment mechanism remains closed.

Step S214: When the recovery torque adjustment mechanism is in an active state, reduce the actual energy recovery torque of the motor according to a preset rule.

In the above step S214, when the recovery torque adjustment mechanism is activated, it indicates that the wheel slip rate is too large, and the wheels are locked or slipped. Therefore, it is necessary to reduce the actual energy of the motor for energy recovery according to the preset rule. The torque is recovered to reduce the amount of braking resistance generated on the motor until the wheel slip rate is reduced to the exit condition of the recovery torque adjustment mechanism, that is, the wheel slip rate is less than the second slip rate threshold, that is, the wheel slip rate is less than the second slip rate threshold. The braking resistance generated is less than or equal to the friction provided by the surface of the wheel, thereby improving the wheel slip due to excessive energy recovery torque.

When the recovery torque adjustment mechanism is in the off state, the wheel slip rate is less than the second slip rate threshold, indicating that there is no wheel slip phenomenon, and therefore there is no need to reduce the actual motor performance according to the preset rules. Energy recovery torque.

In practical applications, the foregoing preset rule may specifically be a preset step length, that is, each time the actual energy recovery torque of the motor is reduced by the preset step length, and then the current wheel slip rate is obtained to determine the state of the recovery torque adjustment mechanism; If the recovery torque adjustment mechanism is in an active state, continue to reduce the actual energy recovery torque of the motor by a preset step length until the wheel slip rate is adjusted so that the recovery torque adjustment mechanism is in a closed state. Specifically, the aforementioned preset step length may be 5Nm, which may be specifically set according to the actual conditions of the motor and the vehicle.

Please refer to FIG. 4, which shows a schematic flow chart of an energy recovery control method provided by a preferred embodiment of the present disclosure, applied to a vehicle, applied to a vehicle, the vehicle includes a motor, and the vehicle is preset with a recovery torque adjustment Mechanism, the vehicle stores a first correspondence between the brake pedal opening and the energy recovery torque, and a second correspondence between the vehicle speed and the energy recovery torque, wherein the method includes steps S401 to S409.

Step S401: Obtain target vehicle state information, where the target vehicle state information includes the current vehicle speed, accelerator pedal opening, and brake pedal opening of the vehicle.

For the above step S401, reference may be made to the detailed description of step S101, which will not be repeated here.

Step S402: If the brake pedal opening degree is greater than or equal to a first opening degree threshold, determine the basic energy recovery torque according to the brake pedal opening degree and the first corresponding relationship.

For the above step S402, reference may be made to the detailed description of step S201, which will not be repeated here.

Step S403: If the current vehicle speed is greater than or equal to the first vehicle speed threshold, and the brake pedal opening degree and the accelerator pedal opening degree are both 0, determine according to the current vehicle speed and the second correspondence relationship The base energy recovers torque.

For the foregoing step S403, reference may be made to the detailed description of step S202, which will not be repeated here.

Step S404: According to the basic energy recovery torque, trigger the motor to perform energy recovery.

For the above step S404, reference may be made to the detailed description of step S103, which will not be repeated here.

Step S405: In the process of energy recovery of the motor, obtain the current vehicle speed and the current wheel speed of the vehicle, and determine the wheel slip rate according to the current vehicle speed and the current wheel speed.

For the above step S405, reference may be made to the detailed description of step S100, which will not be repeated here.

Step S406: If the wheel slip rate is greater than or equal to the first slip rate threshold, control the recovery torque adjustment mechanism to be in an active state.

For the above step S406, reference may be made to the detailed description of step S211, which will not be repeated here.

Step S407: If the wheel slip rate is less than or equal to a second slip rate threshold, control the recovery torque adjustment mechanism to be in a closed state; wherein the second slip rate threshold is less than the first slip rate Threshold.

For the above step S406, reference may be made to the detailed description of step S212, which will not be repeated here.

Step S408: If the wheel slip rate is greater than the second slip rate threshold and less than the first slip rate threshold, control the recovery torque adjustment mechanism to maintain the current state.

For the above step S406, reference may be made to the detailed description of step S213, which will not be repeated here.

Step S409: When the recovery torque adjustment mechanism is in an active state, reduce the actual energy recovery torque of the motor according to a preset rule.

For the above step S406, reference may be made to the detailed description of step S214, which will not be repeated here.

Compared with the prior art, the energy recovery control method described in the embodiments of the present disclosure has the following advantages:

Preset the recovery torque adjustment mechanism in the vehicle in advance, and then in the process of energy recovery by the generator, obtain the current vehicle speed and current wheel speed and determine the wheel slip rate, and determine the recovery torque adjustment mechanism according to the wheel slip rate. Status, and then adjust the actual energy recovery torque of the motor according to the status of the recovery torque adjustment mechanism. Because when controlling the motor for energy recovery, the basic energy recovery torque determined by the target vehicle state information is considered, and the recovery torque adjustment mechanism determined by the wheel slip rate is introduced, and the recovery torque adjustment mechanism has a higher activation. The condition and a lower exit condition can not only dynamically adjust the actual energy recovery torque of the motor according to the wheel slip rate, avoid the situation of wheel lock due to excessive energy recovery torque, but also prevent the critical state of the wheel being locked , There is a situation where the state of the recovery torque adjustment mechanism is frequently switched.

In practical applications, please refer to FIG. 5, which shows an execution flow chart of the energy recovery control method proposed by an embodiment of the present disclosure.

As shown in FIG. 5, in step S501, the motor is triggered to perform energy recovery through the target vehicle status information such as the accelerator pedal and the brake pedal, and then step S502 is entered;

In step S502, the motor is first controlled to perform energy recovery according to normal logic, that is, the motor is controlled to perform energy recovery according to the basic energy recovery torque determined by the target vehicle status information;

In step S503, the wheel speed and vehicle speed are used to detect whether the wheel is about to enter the locked state, that is, whether the wheel slip rate exceeds the first slip rate threshold; if yes, go to step S504, otherwise, go to step S507;

In step S504, the energy recovery torque of the control motor is reduced by X Nm, where X is the preset step size; then step S505 is entered;

In step S505, according to whether the wheel slip rate is lower than the second slip rate threshold, it is determined whether the wheel has been out of the locked state, if the wheel is still in the locked state, return to step S504 to continue to control the energy of the motor The recovered torque is reduced by X Nm; in step S505, if it is determined that the wheel has been out of the locked state, then step S506 is entered;

In step S506, the current actual energy recovery torque of the motor is no longer reduced, and the motor is controlled to perform energy recovery according to the adjusted energy recovery torque in step S505;

In step S507, the motor is directly controlled to perform energy recovery based on the basic energy recovery torque determined by the target vehicle status information.

In practical applications, please refer to FIG. 6, which shows the control principle diagram of the energy recovery control method proposed by the embodiment of the present disclosure. As shown in FIG. 6, the above-mentioned control method is jointly completed by the man-machine interface module 61, the vehicle speed acquisition module 62, the basic recovery torque calculation module 63, the wheel slip rate calculation module 64, the recovery torque adjustment module 65 and the recovery torque response module 66.

Among them, the man-machine interface module 61 is used to obtain the driver's action information to identify and determine the accelerator opening and the brake pedal opening; the vehicle speed collection module 62 is used to collect the current vehicle speed; the basic recovery torque calculation module 63 is It is used to obtain the basic energy recovery torque by querying the preset energy recovery torque table without considering the wheel slip rate; the wheel slip rate calculation module 64 is used to calculate the wheel slip according to the current vehicle speed and the current wheel speed The recovery torque adjustment module 65 is used to adjust the basic energy recovery torque according to the vehicle slip rate; and the recovery torque response module 66 is used to specifically control the motor to perform energy recovery according to the energy recovery torque adjusted by the recovery torque adjustment module 65.

Another objective of the present disclosure is to provide an energy recovery control system, which is applied to a vehicle, and the vehicle includes an electric motor. Please refer to FIG. 5, which shows an energy recovery control system proposed by an embodiment of the present disclosure. Schematic diagram of the structure, the system includes:

The first determining module 10 obtains the current vehicle speed and the current wheel speed of the vehicle during the energy recovery process of the motor, and determines the wheel slip rate according to the current vehicle speed and the current wheel speed;

The control module 20 is configured to adjust the actual energy recovery torque of the motor according to the wheel slip rate.

In the system according to the embodiment of the present disclosure, during the energy recovery process of the generator, the first determining module 10 obtains the current vehicle speed and the current wheel speed of the vehicle, and determines the wheels according to the current vehicle speed and the current wheel speed. Slip rate; and then the control module 20 adjusts the actual energy recovery torque of the motor according to the wheel slip rate. Because in the process of controlling the motor for energy recovery, the wheel slip rate is also considered, and the actual energy recovery torque of the motor can be dynamically adjusted according to the wheel slip rate, which can avoid the wheel lock due to excessive energy recovery torque, and ensure The braking performance of the vehicle is improved, and the driving safety of the vehicle is improved, thereby solving the problem that the wheel lock and drag phenomenon are prone to occur when the existing new energy is used for energy recovery on wet and slippery roads, which affects the driving safety of the vehicle.

Optionally, in the system, the vehicle is preset with a recovery torque adjustment mechanism; the control module 20 includes:

Optionally, the system further includes:

Optionally, in the system, the target vehicle state information includes the current vehicle speed, accelerator pedal opening, and brake pedal opening of the vehicle.

Optionally, in the system, the second determining module includes:

Optionally, in the system, the vehicle stores a first correspondence between the brake pedal opening and the energy recovery torque, and a second correspondence between the vehicle speed and the energy recovery torque;

The second determining unit is specifically configured to: if the current vehicle speed is greater than or equal to the first vehicle speed threshold, and the brake pedal opening degree and the accelerator pedal opening degree are both 0, then according to the current vehicle speed And the second corresponding relationship to determine the basic energy recovery torque.

Optionally, in the system, in the first corresponding relationship, the energy recovery torque increases as the opening of the brake pedal increases;

The energy recovery control control system, the vehicle and the foregoing energy recovery control method have the same advantages over the prior art, and will not be repeated here.

In summary, in the energy recovery control method, system and vehicle provided by the present application, the generator obtains the current vehicle speed and current wheel speed during the energy recovery process, and according to the current vehicle speed and the current wheel speed, Determine the wheel slip rate; then adjust the actual energy recovery torque of the motor according to the wheel slip rate. Because in the process of controlling the motor for energy recovery, the wheel slip rate is also considered, and the actual energy recovery torque of the motor can be dynamically adjusted according to the wheel slip rate, which can avoid the wheel lock due to excessive energy recovery torque, and ensure The braking performance of the vehicle is improved, and the driving safety of the vehicle is improved, thereby solving the problem that the wheel lock and drag phenomenon are prone to occur when the existing new energy is used for energy recovery on wet and slippery roads, which affects the driving safety of the vehicle.

Those skilled in the art can clearly understand that, for the convenience and conciseness of description, the specific working process of the system, device and unit described above can refer to the corresponding process in the foregoing method embodiment, which will not be repeated here.

The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they may be located in One place, or it can be distributed to multiple network units. Some or all of the modules may be selected according to actual needs to achieve the objectives of the solutions of the embodiments. Those of ordinary skill in the art can understand and implement it without creative work.

The various component embodiments of the present disclosure may be implemented by hardware, or by software modules running on one or more processors, or by a combination of them. Those skilled in the art should understand that a microprocessor or a digital signal processor (DSP) may be used in practice to implement some or all of the functions of some or all of the components in the computing processing device according to the embodiments of the present disclosure. The present disclosure can also be implemented as a device or device program (for example, a computer program and a computer program product) for executing part or all of the methods described herein. Such a program for realizing the present disclosure may be stored on a computer-readable medium, or may have the form of one or more signals. Such a signal can be downloaded from an Internet website, or provided on a carrier signal, or provided in any other form.

For example, FIG. 8 shows a computing processing device that can implement the method according to the present disclosure. The computing processing device traditionally includes a processor 1010 and a computer program product in the form of a memory 1020 or a computer readable medium. The memory 1020 may be an electronic memory such as flash memory, EEPROM (Electrically Erasable Programmable Read Only Memory), EPROM, hard disk, or ROM. The memory 1020 has a storage space 1030 for executing program codes 1031 of any method steps in the above methods. For example, the storage space 1030 for program codes may include various program codes 1031 respectively used to implement various steps in the above method. These program codes can be read from or written into one or more computer program products. These computer program products include program code carriers such as hard disks, compact disks (CDs), memory cards, or floppy disks. Such a computer program product is usually a portable or fixed storage unit as described with reference to FIG. 9. The storage unit may have storage segments, storage spaces, etc. arranged similarly to the memory 1020 in the computing processing device of FIG. 8. The program code can be compressed in an appropriate form, for example. Generally, the storage unit includes computer-readable code 1031', that is, code that can be read by a processor such as 1010, which, when run by a computing processing device, causes the computing processing device to execute the method described above. The various steps.

The “one embodiment”, “an embodiment” or “one or more embodiments” referred to herein means that a specific feature, structure or characteristic described in conjunction with the embodiment is included in at least one embodiment of the present disclosure. In addition, please note that the word examples "in one embodiment" here do not necessarily all refer to the same embodiment.

In the instructions provided here, a lot of specific details are explained. However, it can be understood that the embodiments of the present disclosure may be practiced without these specific details. In some instances, well-known methods, structures, and technologies are not shown in detail, so as not to obscure the understanding of this specification.

In the claims, any reference signs placed between parentheses should not be constructed as a limitation to the claims. The word "comprising" does not exclude the presence of elements or steps not listed in the claims. The word "a" or "an" preceding an element does not exclude the presence of multiple such elements. The present disclosure can be realized by means of hardware including several different elements and by means of a suitably programmed computer. In the unit claims listing several devices, several of these devices may be embodied in the same hardware item. The use of the words first, second, and third, etc. do not indicate any order. These words can be interpreted as names.

Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present disclosure, not to limit them; although the present disclosure has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: The technical solutions recorded in the foregoing embodiments are modified, or some of the technical features are equivalently replaced; these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present disclosure.

Claims

An energy recovery control method applied to a vehicle, the vehicle including a motor, characterized in that the method includes:

In the process of energy recovery by the motor, acquiring the current vehicle speed and current wheel speed of the vehicle, and determining the wheel slip rate according to the current vehicle speed and the current wheel speed;

According to the wheel slip rate, the actual energy recovery torque of the motor is adjusted.
The method according to claim 1, wherein the vehicle is preset with a recovery torque adjustment mechanism; and the adjusting the actual energy recovery torque of the motor according to the wheel slip rate comprises:

If the wheel slip rate is greater than or equal to the first slip rate threshold, controlling the recovery torque adjustment mechanism to be in an active state;

If the wheel slip rate is less than or equal to the second slip rate threshold, control the recovery torque adjustment mechanism to be in a closed state; wherein, the second slip rate threshold is less than the first slip rate threshold;

If the wheel slip rate is greater than the second slip rate threshold and less than the first slip rate threshold, controlling the recovery torque adjustment mechanism to maintain the current state;

When the recovery torque adjustment mechanism is in an active state, according to a preset rule, the actual energy recovery torque of the motor is reduced.
The method according to claim 1, wherein in the process of energy recovery of the motor, the current vehicle speed and the current wheel speed of the vehicle are obtained, and the current vehicle speed and the current wheel speed are determined according to the current vehicle speed and the current wheel speed. Before the wheel slip rate, it also includes:

Obtain target vehicle status information;

If it is determined that energy recovery is required according to the target vehicle status information, then determine the basic energy recovery torque according to the target vehicle status information;

According to the basic energy recovery torque, the motor is triggered to perform energy recovery.
The method according to claim 3, wherein the target vehicle state information includes the current vehicle speed, accelerator pedal opening, and brake pedal opening of the vehicle.
The method according to claim 4, wherein if it is determined that energy recovery is required according to the target vehicle status information, then determining the basic energy recovery torque according to the target vehicle status information comprises:

If it is detected that the brake pedal opening is greater than or equal to the first opening threshold, determining the basic energy recovery torque according to the brake pedal opening;

If it is monitored that the current vehicle speed is greater than or equal to the first vehicle speed threshold, and the brake pedal opening degree and the accelerator pedal opening degree are both 0, the basic energy recovery torque is determined according to the current vehicle speed.
The method according to claim 5, wherein the vehicle stores a first correspondence relationship between a brake pedal opening degree and energy recovery torque, and a second correspondence relationship between vehicle speed and energy recovery torque;

If it is determined that energy recovery is required according to the target vehicle state information, then determining the basic energy recovery torque according to the target vehicle state information includes:

If the brake pedal opening degree is greater than or equal to the first opening degree threshold, determining the basic energy recovery torque according to the brake pedal opening degree and the first corresponding relationship;

If the current vehicle speed is greater than or equal to the first vehicle speed threshold, and the brake pedal opening degree and the accelerator pedal opening degree are both 0, then the current vehicle speed and the second corresponding relationship are used to determine The basic energy recovery torque.
The method according to claim 6, wherein, in the first corresponding relationship, the energy recovery torque increases as the opening of the brake pedal increases;

In the second correspondence, when the vehicle speed is less than or equal to the second vehicle speed threshold, the energy recovery torque increases as the vehicle speed increases, and when the vehicle speed is greater than or equal to the second vehicle speed threshold , The energy recovery torque decreases as the vehicle speed increases; wherein the second vehicle speed threshold value is greater than the first vehicle speed threshold value, and the second vehicle speed threshold value is less than or equal to the turning point vehicle speed value, and the turning point vehicle speed value In the external characteristic curve of the motor, the vehicle speed value when the motor changes from a constant torque state to a constant power state.
An energy recovery control system applied to a vehicle, the vehicle including a motor, characterized in that the system includes:

The first determining module, during the energy recovery process of the motor, obtains the current vehicle speed and the current wheel speed of the vehicle, and determines the wheel slip rate according to the current vehicle speed and the current wheel speed;

The control module is used to adjust the actual energy recovery torque of the motor according to the wheel slip rate.
The system according to claim 8, wherein the vehicle is preset with a recovery torque adjustment mechanism; and the control module includes:

The first control unit is configured to control the recovery torque adjustment mechanism to be in an active state if the wheel slip rate is greater than or equal to a first slip rate threshold;

The second control unit is configured to control the recovery torque adjustment mechanism to be in a closed state if the wheel slip rate is less than or equal to a second slip rate threshold; wherein, the second slip rate threshold is less than the first slip rate threshold. A slip rate threshold;

The third control unit is configured to control the recovery torque adjustment mechanism to maintain the current state if the wheel slip rate is greater than the second slip rate threshold and less than the first slip rate threshold;

The fourth control unit is configured to reduce the actual energy recovery torque of the motor according to a preset rule when the recovery torque adjustment mechanism is in an active state.
A vehicle comprising an electric motor, characterized in that the vehicle further comprises the energy recovery control system according to any one of claims 8-9.
A computing processing device, characterized in that it comprises:

A memory in which computer readable codes are stored; and

One or more processors, and when the computer-readable code is executed by the one or more processors, the computing processing device executes the energy recovery control method according to any one of claims 1-7.
A computer program, comprising computer readable code, which when the computer readable code runs on a computing processing device, causes the computing processing device to execute the energy recovery control method according to any one of claims 1-7 .
A computer readable medium in which the computer program according to claim 12 is stored.