轮毂驱动电动汽车复合制动防抱死协调控制及舒适性研究

Research on Anti-lock Braking Coordinate Control System and Comfort of Electric Vehicle

针对轮毂驱动电动汽车电机-液压复合制动系统的协调控制问题和舒适性问题,提出了基于滑模变结构控制算法和模糊算法的控制策略,首先利用滑模算法根据车辆状态参数来计算电动汽车所需的制动总转矩,再利用模糊算法根据制动踏板行程l和电池SOC来计算液压制动和电机制动转矩分配比例。其中液压制动转矩作为汽车制动转矩中的基础制动转矩,用电机转矩调节车轮滑移率,以实现防抱死控制,并且由于液压制动轮缸的压力变化减少,制动舒适性得以提高。最后采用Matlab/Simulink、Amesim和Carsim软件联仿,分别进行高附着和低附着路面仿真,仿真结果表明复合制动系统的防抱死协调控制策略不仅有效,而且改善了ABS介入时的舒适性。

Aiming at the coordination control and comfort problem of the motor hydraulic composite brake system of the hub driven electric vehicle,a control strategy based on the sliding mode variable structure control algorithm and fuzzy algorithm is proposed.Firstly,the total braking torque required by the electric vehicle is calculated by the sliding mode algorithm according to the vehicle state parameters.Then,according to the stroke of brake pedal and SOC(state of charge)value of battery,the distribution proportion of hydraulic braking and motor braking torque is calculated.The hydraulic braking torque is used as the basic braking,and the wheel slip rate is adjusted by motor torque to realize anti-lock control.Moreover,the brake comfort is improved by reducing the pressure change of hydraulic brake wheel cylinder.Matlab/Simulink,AMESim and CarSim software are used to simulate the high adhesion and low adhesion road respectively.The simulation results show that the anti-lock coordinated control strategy of the composite brake system is effective and improves the comfort of the anti-lock control intervention.