Pure electric vehicle speed control method and pure electric vehicle speed control system

Abstract

The invention provides a pure electric vehicle speed control method and a pure electric vehicle speed control system. Signals input by a driver through a pedal and a steering wheel, outer side motor feedback rotation speed signals and inner side motor feedback rotation speed signals are received through a vehicle control unit, a maximum torque Tmax (n1) of an outer side motor is determined according to the outer side motor feedback rotation speed signals, and a maximum torque Tmax (n2) of an inner side motor is determined according to the inner side motor feedback rotation speed signals; followingly, an outer side motor target torque T1 and an inner side motor target torque T2 are obtained through the signals; a vehicle dynamical model obtains a straight travel average vehicle speed v and a vehicle yaw velocity w through the outer side motor target torque signal T1, the inner side motor target torque signal T2, vehicle outer side drive rolling resistance Fr1, vehicle inner side drive rolling resistance Fr2 and vehicle steering resisting moment Mz; and the obtained straight travel average vehicle speed v and the vehicle yaw velocity w are obtained by reference to pavement load variations, and the capability of an electric drive system can also be brought into full play to be enabled to work in an optima state.

Description

Technical field [0001] The present invention relates to the technical field of driving control of electric vehicles, and in particular to a method and system for speed control of pure electric vehicles. Background technique [0002] Currently on the market, the wheels on both sides of a pure electric vehicle driven by dual motors are independently driven by the left and right motors. Only when the speeds of the motors on both sides are the same and the speed difference is zero, the vehicle can keep straight, while the motors on both sides keep constant. The vehicle can only achieve a certain radius of steering when the speed difference is high. [0003] The prior art generally adopts a speed control strategy for driving control of electric vehicles, that is, the accelerator pedal input signal is defined as a given speed signal, and the steering wheel input signal is defined as a speed difference signal. The driving of the vehicle depends on the vehicle speed formed by the input si...

AI Technical Summary

Problems solved by technology

[0005] In view of this, the present invention provides a pure electric vehicle speed control method and system to solve the problem that the motor drive system cannot work in the optimal working range in real time when facing changes in road conditions

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