基于ECE法规和Ⅰ曲线的机电复合制动控制策略

具有再生制动功能的电动汽车制动系统与传统燃油汽车的摩擦制动系统不同,在回收部分制动能量的同时其制动稳定性会发生变化.在保证安全制动距离的前提下,制动能量回收率的提高受到制动稳定性的制约和限制.针对电制动和常规摩擦制动组成的机电复合制动系统,建立了电制动力、电制动力矩和电池充电功率计算模型.考虑到电机转矩特性和电池充电功率限制,以最大化回收制动能量为目标,设计3种不同的机电复合制动控制策略.通过在ADVISOR软件中建立嵌入式仿真模块对制动能量回收率、电池荷电状态和纯电动模式的续驶里程进行了仿真计算和分析.计算结果表明:I曲线和ECE(Economic Commission of Europe safety regulations)法规边界线都不是理想的制动力分配曲线,所提出的制动力分配曲线OABCD综合性能较好,制动能量回收率达到59.56%,且一个循环的荷电状态变化很小,仅降低了4.29%.实车试验表明能量回收能够提高续驶里程.

Control strategy for electro-mechanical braking based on curves of ECE regulations and ideal braking force

The braking system of electric vehicle with regenerative braking is different from friction braking system of conventional fuel vehicle. Regenerative braking system makes braking stability of electric vehicles change when it recovers braking energy of vehicles. The improvement of braking energy recovery ration was restricted by the braking stability under the precondition of safe braking distance. Aiming at the electro-mechanical hybrid braking system composed of electric braking and conventional friction braking, the calculation models of electric braking force, electric braking torque and battery charging power were established. In view of the motor torque characteristics and battery charging power limit, three kinds of control strategies for electro-mechanical hybrid braking were designed for recovering the maximal braking energy. The baking energy recovery ration, state of charge and driving range in pure electric mode were calculated and analyzed by embedding simulation module into the ADVISOR. The calculation results show that the curves of I and economic commission of europe (ECE) regulations boundary are not ideal curves of braking force distribution; the curve OABCD is more feasible; the braking energy recovery ratio should be reached 59.56% by OABCD; and the state of charge changes very little; it decreases only by 4.29%.The test data indicates that the driving range can be increased by energy callback.