CN109823194B

CN109823194B - Ramp starting and hill-holding control system of pure electric vehicle

Info

Publication number: CN109823194B
Application number: CN201910138468.XA
Authority: CN
Inventors: 刘九明; 颜伟; 李鑫
Original assignee: Shanghai Xinguo Power Technology Co ltd
Current assignee: Shanghai Xinguo Power Technology Co ltd
Priority date: 2019-02-25
Filing date: 2019-02-25
Publication date: 2022-12-20
Anticipated expiration: 2039-02-25
Also published as: CN109823194A

Abstract

The invention discloses a ramp starting and hill-holding control system of a pure electric vehicle, which comprises a motor, a vehicle controller, an accelerator pedal, a brake pedal and a motor controller, wherein the accelerator pedal, the brake pedal and the motor controller are connected with the vehicle controller, the motor controller is connected with the motor, the vehicle controller receives the speed, an accelerator pedal signal and a brake pedal signal which are transmitted by the motor controller, and transmits a hill-holding torque curve and a ramp starting torque curve to the motor controller, and the motor controller controls the motor to work according to the received torque curve. The invention does not need an accelerator and a brake pedal, achieves the function of parking the electric automobile on the slope, realizes the functions of stable starting and parking the automobile on the slope, and eliminates the risk of vehicle sliding on the slope and vehicle collision in the traditional method.

Description

Ramp starting and hill-holding control system of pure electric vehicle

Technical Field

The invention relates to a ramp starting and hill-holding control system of a pure electric vehicle.

Background

At present, a hill starting and hill stopping control system of an electric automobile mainly comprises a driver which treads a brake pedal and an accelerator pedal by feet, so that the functions of controlling the vehicle to start and stop on a hill are achieved. When a driver turns to operate an accelerator pedal from a brake pedal, the vehicle can slide backwards for a certain distance under the action of gravity and inertia because the vehicle loses power.

Disclosure of Invention

The invention aims to provide a ramp starting and hill-holding control system of a pure electric vehicle, aiming at the defects of the prior art.

The technical problem solved by the invention can be realized by adopting the following technical scheme:

a pure electric vehicle hill start and hill stop control system comprises a motor, a vehicle controller, an accelerator pedal, a brake pedal and a motor controller, wherein the accelerator pedal, the brake pedal and the motor controller are connected with the vehicle controller, and the motor controller is connected with the motor.

In a preferred embodiment of the invention, when an accelerator and a brake pedal are released and a vehicle has a backward slip tendency, the vehicle is judged to enter a slope parking state at the moment, a control logic of a vehicle controller switches a motor to rotate at a rotating speed ring for operation, the rotating speed of the motor is set to be zero, and a slope parking torque curve is output through PI regulation to enable the vehicle to be in a static slope parking state;

when a brake pedal is released, an accelerator is stepped on and the vehicle is in a low speed state, the vehicle is judged to need to enter a hill for starting, the control logic of the vehicle control unit switches the motor into a rotating speed loop for operation, a constant motor rotating speed is set, and a hill starting torque curve is output through PI regulation so that the vehicle is in a constant-speed hill climbing state;

when the vehicle needs to enter normal running, the control logic of the vehicle controller switches the motor into a torque ring to run, so that the vehicle enters a normal running state.

Due to the adoption of the technical scheme, the invention achieves the function of parking the electric automobile on the slope without an accelerator and a brake pedal, realizes the functions of stably starting and parking the automobile on the slope, and eliminates the risks of vehicle sliding on the slope and vehicle collision in the traditional method.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.

Fig. 1 is a schematic structural view of the present invention.

FIG. 2 is a schematic illustration of a hill-holding torque curve according to an embodiment of the present invention.

FIG. 3 is a schematic representation of a hill start torque curve according to one embodiment of the present invention.

FIG. 4 is a hill hold control logic diagram in accordance with one embodiment of the present invention.

Detailed Description

In order to make the technical means, the creation characteristics, the achievement purposes and the effects of the invention easy to understand, the invention is further explained below.

Referring to fig. 1, the hill starting and hill stopping control system for the pure electric vehicle includes a motor 10, a vehicle controller 30, an accelerator pedal 40, a brake pedal 50 and a motor controller 20 connected to the vehicle controller 30, wherein the motor controller 20 is connected to the motor 10. In this embodiment, the vehicle control unit 30 and the motor controller 20 are connected by a CAN bus, so as to improve the communication reliability.

The vehicle control unit 30 receives the speed, the accelerator pedal signal and the brake pedal signal transmitted from the motor controller 20, and transmits the hill-holding torque curve and the hill-starting torque curve to the motor controller 20, and the motor controller 20 controls the motor 10 to operate according to the received torque curves. Specifically, the vehicle controller 30 reads vehicle information from the motor controller 20 through the CAN bus during vehicle traveling. The vehicle control unit 30 calculates and identifies the road condition of the vehicle in real time, when the vehicle enters a slope and when the accelerator and the brake pedal are released and the vehicle has a backward slip tendency, the vehicle is judged to enter a slope parking state at the moment, the control logic of the vehicle control unit switches the motor into a rotating speed loop to operate, the rotating speed of the motor is set to be zero, and a slope parking torque curve (shown in figure 2) is output through PI regulation to enable the vehicle to be in a stationary slope parking state;

when the brake pedal is released and the accelerator is stepped on, the vehicle is judged to need to enter a hill for starting, the control logic of the vehicle controller switches the motor into a rotating speed loop for running, a constant motor rotating speed is set, and a hill starting torque curve (shown in figure 3) is output through PI regulation so that the vehicle is in a constant-speed hill climbing state. In the whole process, the driver does not need to step on the brake and the accelerator suddenly to realize the functions of starting and stopping the slope;

The vehicle control unit receives the gear, the rotating speed, the accelerator pedal state and the brake pedal state transmitted by the motor, the motor controller is controlled by the ramp control algorithm technology, the motor is controlled to work, the control principle is as shown in figure 4, and the formula is shown in the figure: motor _ Speed _ Out = Kp × Err + Ki ×,

Err＝Speed_Set-Speed_Fb；

description of the signals:

vehicle _ Gear: the gear position signal of the vehicle is sent,

break _ pedal: the signal of the brake pedal is sent to the brake,

accelerator _ pedal: the signal of the accelerator pedal is sent to the driver,

motor _ speed: the signal of the rotating speed of the motor is sent,

motor _ Speed _ Out: the motor outputs a speed command for the motor,

speed _ Set: the motor is set to rotate at a set speed,

speed _ Fb: the actual rotational speed of the motor is,

err: the error between the rotating speed command and the actual rotating speed,

Kp-PI: the coefficient of proportionality is adjusted,

Ki-PI: the integral coefficient is adjusted so that the integral coefficient,

slopeing _ Req: the command of the slope-stopping is given,

SlopeHillStarting _ Req: a hill start command is issued to the driver of the vehicle,

tquue _ Req: the order of the vehicle running is that the vehicle running order,

and the hill-holding and starting logic control module carries out logic judgment according to the states of the gear of the vehicle, the brake pedal, the accelerator pedal and the rotating speed of the motor, and controls the motor to respectively enter a hill-holding state, a hill-holding state or a normal driving state through PI closed-loop operation.

The foregoing shows and describes the general principles and broad features of the present invention and advantages thereof. It will be understood by those skilled in the art that the present invention is not limited to the embodiments described above, which are described in the specification and illustrated only to illustrate the principle of the present invention, but that various changes and modifications may be made therein without departing from the spirit and scope of the present invention, which fall within the scope of the invention as claimed. The scope of the invention is defined by the appended claims and equivalents thereof.

Claims

1. A pure electric vehicle hill start and hill stop control system comprises a motor, a vehicle controller, an accelerator pedal, a brake pedal and a motor controller, wherein the accelerator pedal, the brake pedal and the motor controller are connected with the vehicle controller;

when an accelerator and a brake pedal are loosened and a vehicle has a backward slip tendency, judging that the vehicle needs to enter a slope parking state at the moment, switching a motor into a rotating speed loop to operate by a control logic of the vehicle controller, setting the rotating speed of the motor to be zero, and outputting a slope parking torque curve through PI regulation to enable the vehicle to be in a static slope parking state;

when a brake pedal is released and an accelerator is stepped on, the vehicle is judged to need to enter a hill for starting at the moment, the control logic of the vehicle controller switches the motor into a rotating speed ring for running, a constant motor rotating speed is set, and a hill starting torque curve is output through PI regulation so that the vehicle is in a constant-speed hill climbing state;

when the vehicle needs to enter normal running, the whole vehicle controller controls logic to switch the motor into torque ring running so as to enable the vehicle to enter a normal running state;

the vehicle control unit receives the gear, the rotating speed, the accelerator pedal state and the brake pedal state transmitted by the motor, and the ramp control algorithm controls the motor controller to control the motor to work, wherein the formula is as follows:

Motor_Speed_Out＝Kp*Err+Ki*∫Errdt，

Err＝Speed_Set-Speed_Fb；

description of signals:

motor _ Speed _ Out: the motor outputs a speed command for the motor,

speed _ Set: the motor is set with a rotating speed,

speed _ Fb: the actual rotational speed of the motor is,

kp: the coefficient of proportionality is adjusted,

ki: the integral coefficient is adjusted so that the integral coefficient,