阅读说明：本技术 一种纯电动汽车及其能量回收控制方法、控制系统 (Pure electric vehicle and energy recovery control method and control system thereof ) 是由 员汝娜 赵旭阳 牛占亚 杨欢 陈新波 贺彬起 于 2019-10-23 设计创作，主要内容包括：本发明涉及纯电动汽车的能量回收技术领域,具体涉及一种纯电动汽车及其能量回收控制方法、控制系统,该控制方法包括在纯电动汽车处于制动状态或者滑行状态时,控制纯电动汽车进入相应的能量回收模式；根据能量回收模式,结合当前车速、制动踏板的开度以及能量回收强度档位获取驱动电机的第一馈电扭矩；根据动力电池的最大允许充电功率和驱动电机的转速获得驱动电机的第二馈电扭矩；将查表获得驱动电机的外特性扭矩值作为驱动电机的第三馈电扭矩；比较第一馈电扭矩、第二馈电扭矩和第三馈电扭矩的数值获得最小值,将最小值作为驱动电机的实际馈电扭矩。通过该方法实现对制动能量不同程度的有效回收,满足用户对车辆舒适性和续航能力的不同需求。(The invention relates to the technical field of energy recovery of a pure electric vehicle, in particular to the pure electric vehicle and an energy recovery control method and a control system thereof, wherein the control method comprises the steps of controlling the pure electric vehicle to enter a corresponding energy recovery mode when the pure electric vehicle is in a braking state or a sliding state; according to the energy recovery mode, combining the current vehicle speed, the opening degree of a brake pedal and an energy recovery intensity gear to obtain a first feed torque of a driving motor; obtaining a second feeding torque of the driving motor according to the maximum allowable charging power of the power battery and the rotating speed of the driving motor; obtaining an external characteristic torque value of the driving motor by looking up a table to be used as a third feeding torque of the driving motor; and comparing the values of the first feeding torque, the second feeding torque and the third feeding torque to obtain a minimum value, and taking the minimum value as the actual feeding torque of the driving motor. The method realizes effective recovery of braking energy in different degrees, and meets different requirements of users on vehicle comfort and cruising ability.)

1. The energy recovery control method of the pure electric vehicle is characterized by comprising the following steps of:

when the pure electric vehicle is in a braking state or a sliding state, controlling the pure electric vehicle to enter a corresponding energy recovery mode;

according to the energy recovery mode, combining the current vehicle speed, the opening degree of a brake pedal and an energy recovery intensity gear to obtain a first feed torque of the driving motor;

obtaining a second feeding torque of the driving motor according to the maximum allowable charging power of the power battery and the rotating speed of the driving motor;

obtaining an external characteristic torque value of the driving motor by using a table look-up as a third feeding torque of the driving motor;

and comparing the values of the first feeding torque, the second feeding torque and the third feeding torque to obtain a minimum value, and taking the minimum value as the actual feeding torque of the driving motor.

2. The energy recovery control method of the pure electric vehicle according to claim 1, wherein the method for controlling the pure electric vehicle to enter the corresponding energy recovery mode comprises the following steps:

when the pure electric vehicle is in a braking state, controlling the pure electric vehicle to enter a braking working condition energy recovery mode;

and when the pure electric vehicle is in a sliding state, controlling the pure electric vehicle to enter a sliding working condition energy recovery mode.

3. The energy recovery control method of the pure electric vehicle according to claim 2, wherein the obtaining method of the first feeding torque comprises the following steps:

under a braking working condition energy recovery mode, obtaining the first feed torque through table lookup according to the current vehicle speed, the opening degree of a brake pedal and an energy recovery intensity gear;

and under the sliding working condition energy recovery mode, obtaining the first feed torque through table lookup according to the current vehicle speed and the energy recovery intensity gear.

4. The energy recovery control method for the pure electric vehicle according to claim 2, wherein the method for obtaining the maximum allowable charging power of the power battery comprises the following steps:

and looking up a table according to the residual capacity and the temperature of the power battery to obtain the maximum allowable charging power.

5. The energy recovery control method of the pure electric vehicle according to any one of claims 1 to 4, wherein when the pure electric vehicle is in a braking state or a coasting state, before the pure electric vehicle is controlled to enter a corresponding energy recovery mode, the method further comprises the following steps:

and judging whether the running gear, the speed and the residual electric quantity of the power battery of the pure electric vehicle meet preset conditions.

6. The energy recovery control method of the pure electric vehicle according to claim 1, wherein after the pure electric vehicle enters the corresponding energy recovery mode, if it is detected that the current vehicle speed is less than a preset vehicle speed, the pure electric vehicle is controlled to exit the energy recovery mode.

7. An energy recovery control system of a pure electric vehicle comprises a vehicle control unit, a brake pedal position sensor, an accelerator pedal position sensor, a vehicle speed sensor, a power battery and a driving motor, wherein the brake pedal position sensor, the accelerator pedal position sensor, the vehicle speed sensor, the power battery and the driving motor are respectively connected with the vehicle control unit;

when the vehicle control unit receives a braking signal of the brake pedal position sensor or does not receive the braking signal and an acceleration signal of the acceleration pedal position sensor, the vehicle control unit controls the pure electric vehicle to enter a corresponding energy recovery mode;

the vehicle control unit obtains a first feeding torque of the driving motor according to an energy recovery mode by combining a current vehicle speed detected by a vehicle speed sensor, the braking signal and an energy recovery strength gear of an energy recovery strength gear switch; obtaining a second feeding torque of the driving motor according to the maximum allowable charging power of the power battery and the rotating speed of the driving motor; obtaining an external characteristic torque value of the driving motor by using a table look-up as a third feeding torque of the driving motor; and comparing the values of the first feeding torque, the second feeding torque and the third feeding torque to obtain a minimum value, and taking the minimum value as the actual feeding torque of the driving motor.

8. The energy recovery control system of the pure electric vehicle according to claim 7, further comprising:

the gear position switch is connected with the vehicle control unit and used for switching the running gear of the pure electric vehicle and feeding back the running gear to the vehicle control unit;

the battery management system is connected with the vehicle control unit and used for detecting the residual electric quantity and the temperature of the power battery;

and the vehicle controller judges whether the obtained running gear, the residual electric quantity and the vehicle speed sent by the vehicle speed sensor meet preset conditions.

9. The energy recovery control system of the pure electric vehicle according to claim 7, wherein the control system further comprises:

and the instrument panel is connected with the vehicle control unit through a CAN bus and is used for displaying the energy recovery strength gear signal and the energy recovery strength signal.

10. A pure electric vehicle, characterized in that the vehicle comprises the energy recovery control system of the pure electric vehicle as claimed in any one of claims 7 to 9.

Technical Field

The invention relates to the technical field of energy recovery of pure electric vehicles, in particular to a pure electric vehicle and an energy recovery control method and system thereof.

Background

The existing control methods for recovering the braking energy of the pure electric vehicle mainly comprise a parallel type control method and a serial type control method. In the parallel connection mode, the motor feedback braking force is directly superposed on the original friction braking force, the original friction braking force is not regulated, and the parallel connection mode is convenient to implement, but has the defects of low feedback efficiency and poor braking feeling; the series connection preferentially uses the feedback braking force, has high feedback efficiency and good braking feeling, but needs to be modified or redesigned on the traditional braking system.

An invention patent with patent application publication number CN108790839A discloses an energy recovery control method and an energy recovery control device, the energy recovery control method comprising: judging whether the electric automobile is in a sliding mode or a braking mode; if the vehicle is in the sliding mode or the braking mode, judging whether the current vehicle speed is greater than a preset vehicle speed; if the current vehicle speed is greater than the preset vehicle speed, calculating to obtain a first feedback demand torque according to the current vehicle speed, and calculating to obtain a second feedback demand torque according to the maximum charging power of the battery and the current rotating speed of the motor; and controlling the motor to charge the battery according to the smaller value of the first feedback demand torque and the second feedback demand torque.

In practice, the inventors found that the above prior art has the following disadvantages:

according to the method, energy recovery control can be performed by taking the opening degree of the brake pedal as the switching value, but strong impact feeling can be generated when energy recovery is performed in the braking process, and the driving feeling can be influenced due to unsmooth vehicle speed caused by energy recovery in the deceleration process.

Disclosure of Invention

In order to solve the technical problems, the invention aims to provide a pure electric vehicle and an energy recovery control method and a control system thereof, and the adopted technical scheme is as follows:

in a first aspect, an embodiment of the present invention provides an energy recovery control method for a pure electric vehicle, where the control method includes the following steps:

when the pure electric vehicle is in a braking state or a sliding state, controlling the pure electric vehicle to enter a corresponding energy recovery mode;

according to the energy recovery mode, combining the current vehicle speed, the opening degree of a brake pedal and an energy recovery intensity gear to obtain a first feed torque of the driving motor;

obtaining a second feeding torque of the driving motor according to the maximum allowable charging power of the power battery and the rotating speed of the driving motor;

obtaining an external characteristic torque value of the driving motor by using a table look-up as a third feeding torque of the driving motor;

and comparing the values of the first feeding torque, the second feeding torque and the third feeding torque to obtain a minimum value, and taking the minimum value as the actual feeding torque of the driving motor.

Further, the method for controlling the pure electric vehicle to enter the corresponding energy recovery mode comprises the following steps:

when the pure electric vehicle is in a braking state, controlling the pure electric vehicle to enter a braking working condition energy recovery mode;

and when the pure electric vehicle is in a sliding state, controlling the pure electric vehicle to enter a sliding working condition energy recovery mode.

Further, the first feeding torque obtaining method includes the steps of:

under a braking working condition energy recovery mode, obtaining the first feed torque through table lookup according to the current vehicle speed, the opening degree of a brake pedal and an energy recovery intensity gear;

under the sliding working condition energy recovery mode, obtaining the first feed torque through table lookup according to the current vehicle speed and the energy recovery intensity gear;

further, the method for obtaining the maximum allowable charging power of the power battery comprises the following steps:

and looking up a table according to the residual capacity and the temperature of the power battery to obtain the maximum allowable charging power.

Further, when the pure electric vehicle is in a braking state or a sliding state, before the pure electric vehicle is controlled to enter a corresponding energy recovery mode, the method further comprises the following steps:

and judging whether the running gear, the speed and the residual electric quantity of the power battery of the pure electric vehicle meet preset conditions.

Further, after the pure electric vehicle enters the corresponding energy recovery mode, if the current vehicle speed is detected to be less than the preset vehicle speed, the pure electric vehicle is controlled to exit the energy recovery mode.

In a second aspect, another embodiment of the present invention provides an energy recovery control system for a pure electric vehicle, where the control system includes a vehicle controller, a brake pedal position sensor, an accelerator pedal position sensor, a vehicle speed sensor, a power battery, and a driving motor, which are respectively connected to the vehicle controller, and the vehicle controller is connected to an energy recovery strength shift switch;

when the vehicle control unit receives a braking signal of the brake pedal position sensor or does not receive the braking signal and an acceleration signal of the acceleration pedal position sensor, the vehicle control unit controls the pure electric vehicle to enter a corresponding energy recovery mode;

the vehicle control unit obtains a first feeding torque of the driving motor according to an energy recovery mode by combining a current vehicle speed detected by a vehicle speed sensor, the braking signal and an energy recovery strength gear of an energy recovery strength gear switch; obtaining a second feeding torque of the driving motor according to the maximum allowable charging power of the power battery and the rotating speed of the driving motor; obtaining an external characteristic torque value of the driving motor by using a table look-up as a third feeding torque of the driving motor; and comparing the values of the first feeding torque, the second feeding torque and the third feeding torque to obtain a minimum value, and taking the minimum value as the actual feeding torque of the driving motor.

Further, the system further comprises:

the gear position switch is connected with the vehicle control unit and used for switching the running gear of the pure electric vehicle and feeding back the running gear to the vehicle control unit;

the battery management system is connected with the vehicle control unit and used for detecting the residual electric quantity and the temperature of the power battery;

and the vehicle controller judges whether the obtained running gear, the residual electric quantity and the vehicle speed sent by the vehicle speed sensor meet preset conditions.

Further, the control system further includes:

and the instrument panel is connected with the vehicle control unit through a CAN bus and is used for displaying the energy recovery strength gear signal and the energy recovery strength signal.

In a third aspect, another embodiment of the present invention provides a pure electric vehicle, where the pure electric vehicle includes any one of the energy recovery control systems of the pure electric vehicles.

The invention has the following beneficial effects:

the embodiment of the invention provides an energy recovery control method of a pure electric vehicle, which is characterized in that a relation table between a motor braking torque and a vehicle speed section, a braking energy recovery gear and a braking pedal opening degree is obtained through calibration through different energy recovery modes, and the driving range of the pure electric vehicle can be effectively improved through the braking energy recovery; meanwhile, the effective recovery of different degrees of braking energy is realized through the energy recovery intensity gear, the situation that the impact sense is strong or the vehicle speed is unstable in the braking or sliding process is avoided, and different requirements of users on the comfort and the cruising ability of the vehicle are met.

Drawings

Fig. 1 is a flowchart of an energy recovery control method for a pure electric vehicle according to an embodiment of the present invention;

fig. 2 is a flowchart of an energy recovery control method for a pure electric vehicle according to another embodiment of the present invention;

fig. 3 is a system block diagram of an energy recovery control system of a pure electric vehicle according to an embodiment of the present invention.

Detailed Description

In order to further illustrate the technical means and effects of the present invention for achieving the predetermined object, the following detailed description, the structure, the features and the effects of the energy recovery control method and the energy recovery control system for the pure electric vehicle according to the present invention are provided with reference to the accompanying drawings and the preferred embodiments. In the following description, different "one embodiment" or "another embodiment" refers to not necessarily the same embodiment. Furthermore, the particular features, structures, or characteristics may be combined in any suitable manner in one or more embodiments.

It will be understood that when an element is referred to as being "connected" to another element, it can be directly on the other element or intervening elements may also be present.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention.

The following describes a specific scheme of the pure electric vehicle and an energy recovery control method and a control system thereof in detail with reference to the accompanying drawings.

Referring to fig. 1, which shows a flowchart of an energy recovery control method for a pure electric vehicle according to an embodiment of the present invention, in order to solve technical problems that an impact feeling of energy recovery is strong during braking and a vehicle speed is not smooth due to energy recovery during deceleration, the energy recovery control method performs energy recovery while comprehensively considering an opening degree of a brake pedal, an energy recovery gear, and external characteristics of a driving motor, and specifically, the energy recovery control method includes the following steps:

and S001, controlling the pure electric vehicle to enter a corresponding energy recovery mode when the pure electric vehicle is in a braking state or a sliding state.

The invention enters a corresponding energy recovery mode when the vehicle brakes or slides. Specifically, whether the vehicle is in a braking state is judged according to whether a brake pedal is stepped down, and the vehicle enters a braking working condition energy recovery mode in the braking state; if the brake pedal is not pressed down and the accelerator pedal is not pressed down, the vehicle is judged to be in a sliding state at the moment, and then the vehicle enters a sliding working condition energy recovery mode.

And step S002, acquiring a first feed torque of the driving motor according to the corresponding energy recovery mode by combining the current vehicle speed, the opening degree of the brake pedal and the energy recovery strength gear.

The current speed is acquired by firstly acquiring the rotating speed of the motor through a rotary transformer arranged on the driving motor and then converting a rotating speed signal of the motor into the speed of the pure electric vehicle. In the present embodiment, the vehicle speed is represented by v, where v1, v2 … … vn represent different vehicle speeds.

The opening degree of the brake pedal refers to the degree of the brake pedal being pressed, the opening degree of the brake pedal is represented by KB, wherein KB1 and KB2 … … KBm represent different opening degrees of the brake pedal, the opening degree of the brake pedal is represented by 0-100%, wherein KB1 is equal to 0% and represents not being pressed, and KBm is equal to 100% and represents that the brake pedal is pressed to the bottom.

The energy recovery intensity gear is connected with the vehicle control unit, the energy recovery intensity gear is switched according to external operation, and corresponding trigger signals are sent to the vehicle control unit while the energy recovery intensity gear is switched. Specifically, in the present embodiment, the energy recovery intensity steps can be set in multiple steps according to the recovery intensity, different energy recovery intensity steps are represented by B1 and B2 … … Bx, and the energy recovery intensity is stronger as the gradient of the energy recovery intensity steps is increased.

In this embodiment, on the premise of ensuring the stability and safety of the braking process, the braking torque of the driving motor is calibrated, the calibration result in the braking condition energy recovery mode is stored as table 1, and the calibration result in the coasting condition energy recovery mode is stored as table 2.

TABLE 1 braking Torque calibration results for drive motors in braking Condition energy recovery mode

TABLE 2 braking Torque calibration results for the drive Motor under coast Condition energy recovery mode

As can be seen from table 1, in the braking condition energy recovery mode, when the vehicle is in different energy recovery intensity gears, different opening degrees of the brake pedal, and different vehicle speeds, the feeding torques are different. For example, when the energy recovery strength is B1, the opening degree of the brake pedal is KB1, and the vehicle speed is v1, the corresponding initial feeding torque is T111, and T111 may be 10 Nm.

As can be seen from table 2, in the coasting condition energy recovery mode, the opening degrees of the brake pedal and the accelerator pedal are both zero, and the vehicle is in the coasting state, and when the vehicle is in different energy recovery intensity gears, different vehicle speeds correspond to different feeding torques, for example, when the energy recovery intensity gear is B1, and the vehicle speed is v1, the corresponding initial feeding torques are T11, and T11 may also be 10 Nm.

In the specific application process, according to the corresponding energy recovery mode, in combination with the current vehicle speed, the opening degree of the brake pedal and the energy recovery intensity gear, the first feeding torque of the driving motor can be obtained by inquiring the corresponding content of the prestored table 1 or table 2.

And step S003, obtaining a second feeding torque of the driving motor according to the maximum allowable charging power of the power battery and the rotating speed of the driving motor.

The maximum allowable charging power Pmax is obtained by inquiring a pre-stored power table according to the acquired residual electric quantity SOC and the temperature T of the power battery after the pure electric vehicle enters the energy recovery mode.

The relevant parameters of the power battery are obtained through a battery management system of the pure electric vehicle, the parameters comprise the residual electric quantity SOC and the temperature T of the power battery, the relation between the maximum allowable charging power Pmax of the power battery and the residual electric quantity SOC and the temperature T is calibrated in advance, as shown in a table 3, and the content of the table 3 is stored in the pure electric vehicle.

TABLE 3 maximum allowable charging power of power battery

The rotating speed of the driving motor is obtained by a rotary transformer arranged on the driving motor, the rotating speed of the driving motor is represented by n, and a second feeding torque of the driving motor is obtained according to the relation between the rotating speed n of the driving motor, the maximum allowable charging power Pmax of the power battery and the torque: pmax 9550/n, wherein 9550 is a coefficient.

And step S004, obtaining an external characteristic torque value of the driving motor as a third feeding torque of the driving motor by using the table lookup.

The external characteristics of the driving motor in the feed mode are tested through the dynamometer, the maximum torque corresponding to different rotating speeds of the driving motor in the feed mode is obtained, and the corresponding relation data of the rotating speeds and the torque is stored in the pure electric vehicle.

And after the pure electric vehicle enters an energy recovery mode, looking up a table according to the current rotating speed n to obtain a third feed torque.

And step S005, comparing the values of the first feeding torque, the second feeding torque and the third feeding torque to obtain a minimum value, and taking the minimum value as the actual feeding torque of the driving motor.

In summary, according to the energy recovery control method for the pure electric vehicle provided by the embodiment of the invention, the relation table between the braking torque of the motor and the vehicle speed section, the braking energy recovery gear and the opening degree of the braking pedal is obtained through calibration, so that the reliability and the accuracy of the braking torque are ensured; meanwhile, when the vehicle enters an energy recovery state, the larger the braking force is along with the increase of the gradient of the energy recovery intensity gear, the more the energy is recovered, and when the braking energy at a low gear is recovered, the braking force is the smallest, so that the driving feeling is hardly influenced, and the higher the braking energy recovery gear is, the stronger the dragging feeling of the whole vehicle is, although the driving feeling is not good, the largest energy recovery force is; therefore, the user can effectively recover the braking energy to different degrees by selecting the energy recovery intensity gear, and different requirements of the user on the comfort and the cruising ability of the vehicle are met. For further explanation of the embodiments of the present invention, please refer to fig. 2, which shows a flowchart of an energy recovery control method for a pure electric vehicle according to another embodiment of the present invention, where the control method includes:

step 201, collecting the current speed, the opening degree of an accelerator pedal, the opening degree of a brake pedal, an energy recovery intensity gear, the rotating speed of a driving motor and the residual electric quantity and the temperature of a power battery of the pure electric vehicle.

Step 202, judging whether the gear of the pure electric vehicle is a forward gear, if so, executing step 203; if not, go to step 213.

Step 203, judging whether the vehicle speed meets a preset condition, for example, whether the vehicle speed v meets the condition: v is more than 10km/h and less than or equal to 100km/h, if yes, executing the step 204, and if not, executing the step 213.

Step 204, judging whether the remaining capacity SOC of the power battery meets a preset condition, for example, the SOC is more than 20% and less than or equal to 90%, if so, executing step 205, and if not, executing step 213;

step 205, determining whether the brake pedal is pressed, that is, determining the opening KB of the brake pedal, if so, executing step 207, otherwise, executing step 206;

in step 206, it is determined whether the accelerator opening is zero, that is, the accelerator opening is determined, and if yes, step 208 is executed, and if no, step 213 is executed.

And step 207, controlling the pure electric vehicle to enter a braking working condition energy recovery mode, and obtaining a first feed torque of the driving motor through table lookup according to the current vehicle speed, the opening degree of a brake pedal and an energy recovery intensity gear.

And 208, controlling the pure electric vehicle to enter a sliding working condition energy recovery mode, and obtaining a first feed torque of the driving motor through table lookup according to the current vehicle speed and the energy recovery intensity gear.

Step 209, obtaining the maximum allowable charging power of the power battery according to the remaining capacity and the temperature of the power battery by looking up a table; calculating to obtain a second feed torque of the driving motor according to the rotating speed of the driving motor and the maximum allowable charging power;

step 210, looking up a table to obtain a torque value of the external characteristic of the motor in the feeding mode, and taking the torque value as a third feeding torque;

and step 211, taking the minimum value of the first feeding torque, the second feeding torque and the third feeding torque as the actual feeding torque of the driving motor.

Step 212, determining whether the current vehicle speed is greater than or equal to a preset minimum value, for example, v > 10km/h, if so, executing step 204, and if not, executing step 213.

And step 213, controlling the pure electric vehicle to exit the energy recovery mode.

In summary, another embodiment of the present invention provides an energy recovery control method for a pure electric vehicle, where the control method further ensures that energy recovery is performed on the premise that a normal operation state of the vehicle is not affected by limiting a lowest speed of the vehicle after the vehicle enters an energy recovery mode in a forward gear, so as to avoid energy recovery in a state that does not meet a preset condition, and further avoid unstable operation of the vehicle due to energy recovery.

Referring to fig. 3, an embodiment of the present invention further provides a structural block diagram of an energy recovery control system of a pure electric vehicle, where the control system includes a vehicle controller 301, and a brake pedal position sensor 305, an accelerator pedal position sensor 306, a vehicle speed sensor 302, a power battery 307, and a driving motor 308 that are respectively connected to the vehicle controller 301, and the vehicle controller 301 is connected to an energy recovery strength shift switch 304. The power battery 307 is connected with the vehicle control unit 301 through a battery management system 3071, and the battery management system 3071 is connected with the vehicle control unit 301 through a CAN bus; the driving motor 308 is connected to the vehicle control unit 301 through a motor controller 3081, and the motor controller 3081 is connected to the vehicle control unit 301 through a CAN bus.

The vehicle control unit 301 controls the pure electric vehicle to enter the corresponding energy recovery mode when receiving the braking signal of the brake pedal position sensor 305 or when not receiving the braking signal and the acceleration signal of the accelerator pedal position sensor 306. Specifically, when receiving a braking signal of the brake pedal position sensor 305, the vehicle control unit 301 controls the pure electric vehicle to enter a braking condition energy recovery mode; when the vehicle control unit 301 does not receive the braking signal and the acceleration signal of the accelerator pedal position sensor 306, the pure electric vehicle is controlled to enter the coasting condition energy recovery mode.

The vehicle control unit 301 obtains a first feeding torque of the driving motor 308 according to the corresponding energy recovery mode by combining the current vehicle speed detected by the vehicle speed sensor 302, the braking signal and the energy recovery strength gear of the energy recovery strength gear switch 304. Specifically, in the energy recovery mode of the braking working condition, a first feeding torque of the driving motor 308 is obtained according to the current vehicle speed, the braking signal and the energy recovery intensity gear table look-up; in the coasting condition energy recovery mode, a first feeding torque of the driving motor 308 is obtained according to the current vehicle speed and the energy recovery intensity gear lookup table. Then, a second feeding torque of the driving motor 308 is obtained according to the maximum allowable charging power of the power battery 307 and the rotation speed of the driving motor 308; finally, the obtained external characteristic torque value of the driving motor 308 is used as the third feeding torque of the driving motor 308 through table lookup. The values of the first feeding torque, the second feeding torque, and the third feeding torque are compared to obtain a minimum value, and the minimum value is taken as the actual feeding torque of the drive motor 308.

As a preferred embodiment of the present invention, the system further includes a gear position switch 303 and a battery management system 3071, where the gear position switch 303 is connected to the vehicle controller 301, and is configured to switch an operating gear of the pure electric vehicle and feed back the operating gear to the vehicle controller 301. The battery management system 3071 is connected to the vehicle control unit 301 for feeding back the remaining power of the power battery 307. The vehicle control unit 301 determines whether the obtained operating gear, the remaining power amount, and the vehicle speed sent by the vehicle speed sensor 302 meet preset conditions, where the preset conditions are that the operating gear is a forward gear and one of the preset conditions is met. The remaining capacity is greater than the preset minimum capacity value and less than the preset maximum capacity value, for example, one of the preset conditions is satisfied when the remaining capacity is between 20% and 90%. The vehicle speed is greater than the preset minimum vehicle speed value and less than the preset maximum vehicle speed, for example, the vehicle speed meets one of the preset conditions when the vehicle speed is between 10km/h and 100 km/h.

As a preferred embodiment of the present invention, the vehicle controller 301 is connected to the anti-lock system 310 and the meter 309 through CAN buses, respectively. The meter 309 is used to display the energy recovery intensity level signal and the energy recovery intensity signal.

The embodiment of the invention also provides a pure electric vehicle, and the pure electric vehicle adopts the energy recovery control system provided by any one of the embodiments.

According to the pure electric vehicle disclosed by the embodiment of the invention, the driving range of the pure electric vehicle can be effectively improved by the energy recovery control method; meanwhile, the effective recovery of the braking energy in different degrees can be realized through the energy recovery intensity gear, and different requirements of users on the comfort and the cruising ability of the vehicle are met.

Finally, it should be noted that: the above examples are only intended to illustrate the technical solution of the present invention, but not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; and such modifications or substitutions do not depart from the spirit and scope of the corresponding technical solutions of the embodiments of the present invention.