阅读说明：本技术 防动力电池can通讯丢失引发动力中断的方法、系统及车辆 (Method and system for preventing power interruption caused by power battery CAN communication loss and vehicle ) 是由 刘小俊 夏永光 李宗华 严钦山 杨官龙 于 2021-07-29 设计创作，主要内容包括：本发明公开了一种防动力电池CAN通讯丢失引发动力中断的方法、系统及车辆,包括：将车速依次划分为多个车速段,且不同车速段的最高车速限制值不同；将有效电池电量依次划分为多个电量区间,且不同电量区间的电机驱动功率限制值不同；根据最高车速限制值和当前车速计算出当前最高车速限制下的电机最大驱动扭矩限制值A；根据电机驱动功率限制值、电机转速及电机效率计算出当前电机驱动功率限制值下的电机最大驱动扭矩限制值B；根据电机最大驱动扭矩限制值A、电机最大驱动扭矩限制值B对驾驶员需求扭矩进行限制,得到电机驱动扭矩需求。本发明针对不同的使用场景制定不同的处理措施,从而对行驶安全性、电池安全有较大提升。(The invention discloses a method, a system and a vehicle for preventing power interruption caused by power battery CAN communication loss, wherein the method comprises the following steps: dividing the vehicle speed into a plurality of vehicle speed sections in sequence, wherein the highest vehicle speed limit values of different vehicle speed sections are different; the effective battery electric quantity is divided into a plurality of electric quantity intervals in sequence, and the limit values of the motor driving power in different electric quantity intervals are different; calculating a maximum driving torque limit value A of the motor under the current maximum vehicle speed limit according to the maximum vehicle speed limit value and the current vehicle speed; calculating a motor maximum driving torque limit value B under the current motor driving power limit value according to the motor driving power limit value, the motor rotating speed and the motor efficiency; and limiting the torque required by the driver according to the maximum driving torque limit value A and the maximum driving torque limit value B of the motor to obtain the driving torque requirement of the motor. The invention makes different processing measures aiming at different use scenes, thereby greatly improving the driving safety and the battery safety.)

1. A method for preventing power interruption caused by power battery CAN communication loss is characterized by comprising the following steps:

dividing the vehicle speed into a plurality of vehicle speed sections in sequence, wherein the highest vehicle speed limit values of different vehicle speed sections are different;

the effective battery electric quantity is divided into a plurality of electric quantity intervals in sequence, and the limit values of the motor driving power in different electric quantity intervals are different;

calculating a maximum driving torque limit value A of the motor under the current maximum vehicle speed limit according to the maximum vehicle speed limit value and the current vehicle speed;

calculating a motor maximum driving torque limit value B under the current motor driving power limit value according to the motor driving power limit value, the motor rotating speed and the motor efficiency;

and limiting the torque required by the driver according to the maximum driving torque limit value A and the maximum driving torque limit value B of the motor to obtain the driving torque requirement of the motor.

2. The method of claim 1 for preventing power interruption due to power battery CAN communication loss, wherein: dividing the vehicle speed into three vehicle speed sections of 0-30 km/h, 30-60 km/h and more than 60 km/h;

when the current vehicle speed is less than or equal to 30km/h, the highest vehicle speed limit value is 30 km/h;

when the current vehicle speed is greater than 30km/h, the maximum vehicle speed limit value is max (current vehicle speed, 60 km/h).

3. The method of claim 2 for preventing power interruption due to power battery CAN communication loss, wherein:

dividing the effective battery electric quantity into two intervals of more than 0.5 times of the rated battery electric quantity and 0.5 times and less than the rated battery electric quantity;

when the electric quantity of the effective battery is greater than 0.5 time of rated electric quantity, the limit value of the driving power of the motor is 0.8 time of the maximum discharge power of the effective battery, and the consumed power of the high-voltage component is subtracted;

when the electric quantity of the effective battery is less than or equal to 0.5 times of rated electric quantity, the limit value of the driving power of the motor is 0.5 times of the maximum discharging power of the effective battery, and the consumed power of the high-voltage component is subtracted.

4. The method of claim 3 for preventing power interruption due to power battery CAN communication loss, wherein: the method for calculating the maximum driving torque limit value A of the motor comprises the following steps:

maximum driving torque limit value of motorKP, KI and KD are respectively proportional parameters, integral parameters and differential parameters in PID; (t) maximum vehicle speed limit-current vehicle speed; t is a time constant.

5. The method of claim 4 for preventing power interruption due to power battery CAN communication loss, wherein: the method for calculating the maximum driving torque limit value B of the motor comprises the following steps:

maximum driving torque limit value of motorWhere 9550 is a constant.

6. The method of claim 5 for preventing power interruption due to power battery CAN communication loss, wherein: the method of calculating the motor drive torque request is as follows:

motor drive torque demand ═

min (driver demand torque, motor maximum drive torque limit a, motor maximum drive torque limit B).

7. The utility model provides a prevent that power battery CAN communication loses and arouses system of power interrupt, includes memory and controller, the controller is connected with the memory, its characterized in that: the memory stores a computer readable program, and the controller CAN execute the steps of the method for preventing the power interruption caused by the CAN communication loss of the power battery according to any one of claims 1 to 6 when calling the computer readable program.

8. A vehicle, characterized in that: a system for preventing a power interruption caused by a power battery CAN communication loss according to claim 7 is used.

Technical Field

The invention belongs to the technical field of pure electric vehicles, and particularly relates to a method, a system and a vehicle for preventing power interruption caused by power battery CAN communication loss.

Background

Under the influence of energy crisis, environmental pollution, greenhouse effect and other problems, new energy automobiles, particularly pure electric automobiles, will become a necessary trend. The pure electric vehicle has the advantages of energy conservation, environmental protection, strong dynamic property, simple structure and the like, and is widely concerned by scientific research institutions and enterprises.

The power battery is used as a power source of the pure electric vehicle, the CAN communication of the power battery comprises critical signals such as battery electric quantity, maximum charging power and maximum discharging power, and the driving system limits driving torque and energy recovery torque according to the signals. If the communication is lost, improper treatment measures can cause power interruption in the driving process or deep battery feeding, and the life and property safety of a driver is affected.

Therefore, there is a need to develop a method, a system and a vehicle for preventing power interruption caused by power battery CAN communication loss.

Disclosure of Invention

The invention aims to provide a method, a system and a vehicle for preventing power interruption caused by power battery CAN communication loss, which CAN make different processing measures aiming at different use scenes so as to improve the driving safety and the battery safety.

In a first aspect, the method for preventing power interruption caused by power battery CAN communication loss according to the present invention includes the following steps:

dividing the vehicle speed into a plurality of vehicle speed sections in sequence, wherein the highest vehicle speed limit values of different vehicle speed sections are different;

the effective battery electric quantity is divided into a plurality of electric quantity intervals in sequence, and the limit values of the motor driving power in different electric quantity intervals are different;

calculating a maximum driving torque limit value A of the motor under the current maximum vehicle speed limit according to the maximum vehicle speed limit value and the current vehicle speed;

calculating a motor maximum driving torque limit value B under the current motor driving power limit value according to the motor driving power limit value, the motor rotating speed and the motor efficiency;

and limiting the torque required by the driver according to the maximum driving torque limit value A and the maximum driving torque limit value B of the motor to obtain the driving torque requirement of the motor.

Optionally, dividing the vehicle speed into three vehicle speed sections of 0-30 km/h, 30-60 km/h and more than 60 km/h;

when the current vehicle speed is less than or equal to 30km/h, the highest vehicle speed limit value is 30 km/h;

when the current vehicle speed is greater than 30km/h, the maximum vehicle speed limit value is max (current vehicle speed, 60 km/h).

Optionally, dividing the effective battery power into two intervals of more than 0.5 times of the rated battery power, and 0.5 times and less than the rated battery power;

when the electric quantity of the effective battery is greater than 0.5 time of rated electric quantity, the limit value of the driving power of the motor is 0.8 time of the maximum discharge power of the effective battery, and the consumed power of the high-voltage component is subtracted;

when the electric quantity of the effective battery is less than or equal to 0.5 times of rated electric quantity, the limit value of the driving power of the motor is 0.5 times of the maximum discharging power of the effective battery, and the consumed power of the high-voltage component is subtracted.

Optionally, the maximum driving torque limit value a of the motor is calculated as follows:

maximum driving torque limit value of motorKP, KI and KD are respectively proportional parameters, integral parameters and differential parameters in PID; (t) maximum vehicle speed limit-current vehicle speed; t is a time constant.

Optionally, the maximum driving torque limit value B of the motor is calculated as follows:

maximum driving torque limit value of motorWhere 9550 is a constant.

Optionally, the method of calculating the motor drive torque request is as follows:

the motor drive torque request is min (driver requested torque, motor maximum drive torque limit a, motor maximum drive torque limit B).

In a second aspect, the system for preventing power interruption caused by power battery CAN communication loss according to the present invention includes a memory and a controller, where the controller is connected to the memory, and a computer readable program is stored in the memory, and when the controller calls the computer readable program, the steps of the method for preventing power interruption caused by power battery CAN communication loss according to the present invention CAN be executed.

In a third aspect, the invention provides a vehicle employing a system for preventing power interruption caused by power battery CAN communication loss according to the invention.

The invention has the following advantages: different processing measures are made according to different use scenes, so that the driving safety and the battery safety are greatly improved. The method limits the driving power of the motor and the highest speed of the vehicle by referring to the power consumption of the high-voltage component according to the electric quantity (hereinafter referred to as effective battery electric quantity) and the maximum discharge power (hereinafter referred to as effective battery maximum discharge power) of the power battery before the CAN communication of the power battery system is interrupted and the current speed of the vehicle, so that the driving torque is limited, and the power interruption of the whole vehicle CAN be avoided after the CAN communication of the power battery system of the pure electric vehicle is lost.

Drawings

FIG. 1 is a schematic view of calculation of the maximum vehicle speed limit value in the present embodiment;

FIG. 2 is a schematic diagram illustrating the calculation of the motor driving power limit value in the present embodiment;

FIG. 3 is a schematic diagram illustrating the calculation of the maximum driving torque limit value A of the motor in the present embodiment;

FIG. 4 is a schematic diagram illustrating the calculation of the maximum driving torque limit value B of the motor in the present embodiment;

fig. 5 is a schematic diagram of the motor drive torque demand calculation in the present embodiment.

Detailed Description

The invention will be further explained with reference to the drawings.

In this embodiment, a method for preventing power interruption caused by power battery CAN communication loss includes the following steps:

(1) the vehicle speed is divided into a plurality of vehicle speed sections in sequence, and the highest vehicle speed limit values of different vehicle speed sections are different.

As shown in FIG. 1, in the embodiment, the vehicle speed is divided into three vehicle speed sections of 0-30 km/h, 30-60 km/h and more than 60 km/h; when the current vehicle speed is less than or equal to 30km/h, the highest vehicle speed limit value is 30 km/h; when the current vehicle speed is greater than 30km/h, the maximum vehicle speed limit value is max (current vehicle speed, 60 km/h).

(2) The effective battery electric quantity is divided into a plurality of electric quantity intervals in sequence, and the motor driving power limiting values of different electric quantity intervals are different.

As shown in fig. 2, in the present embodiment, the effective battery power is divided into two intervals, i.e., the battery rated power is 0.5 times or more, and the battery rated power is 0.5 times or less. When the electric quantity of the effective battery is larger than 0.5 time of rated electric quantity, the limit value of the driving power of the motor is 0.8 time of the maximum discharging power of the effective battery, and the consumed power of the high-voltage component is subtracted. When the electric quantity of the effective battery is less than or equal to 0.5 times of rated electric quantity, the limit value of the driving power of the motor is 0.5 times of the maximum discharging power of the effective battery, and the consumed power of the high-voltage component is subtracted.

(3) And calculating the maximum driving torque limit value A of the motor under the current maximum vehicle speed limit according to the maximum vehicle speed limit value and the current vehicle speed.

As shown in fig. 3, in the present embodiment, the method for calculating the maximum driving torque limit value a of the motor is as follows:

maximum driving torque limit value of motorKP, KI and KD are respectively proportional parameters, integral parameters and differential parameters in PID; (t) maximum vehicle speed limit-current vehicle speed; t is a time constant.

(4) And calculating a motor maximum driving torque limit value B under the current motor driving power limit value according to the motor driving power limit value, the motor rotating speed and the motor efficiency.

As shown in fig. 4, in the present embodiment, the method for calculating the maximum driving torque limit value B of the motor is as follows:

maximum driving torque limit value of motorWhere 9550 is a constant.

(5) And limiting the torque required by the driver according to the maximum driving torque limit value A and the maximum driving torque limit value B of the motor to obtain the driving torque requirement of the motor.

As shown in fig. 5, in the present embodiment, the method for calculating the motor drive torque demand is as follows:

the motor drive torque request is min (driver requested torque, motor maximum drive torque limit a, motor maximum drive torque limit B).

In this embodiment, the driver required torque is obtained by looking up a corresponding relation table of the driver required torque, the accelerator pedal opening and the current vehicle speed according to the accelerator pedal opening and the current vehicle speed, wherein the corresponding relation table of the driver required torque, the accelerator pedal opening and the current vehicle speed is obtained by calibration.

In this embodiment, a system for preventing power interruption caused by power battery CAN communication loss includes a memory and a controller, where the controller is connected to the memory, a computer readable program is stored in the memory, and when the controller calls the computer readable program, the steps of the method for preventing power interruption caused by power battery CAN communication loss in this embodiment CAN be executed.

In this embodiment, a vehicle adopts the system for preventing the power interruption caused by the power battery CAN communication loss as described in this embodiment.