电动汽车真空助力制动系统的匹配优化方法研究

Study in Matching Optimization Method of Vacuum Assisted Brake System of Electric Vehicle

针对电动汽车制动系统的真空助力系统参数进行匹配与优化，设计了匹配与计算流程，建立了制动系统的数学模型，提出了真空泵抽气速率、真空罐体积和启停真空度等真空助力系统参数的优化方法。以电动中巴为例，匹配计算制动系统所需的最小真空度及真空泵抽气速率，分析真空罐体积与抽气速率的关系；通过建模仿真，分析启停真空度与抽气速率、工作时间和能耗的相互影响。结果表明：真空罐体积为5L、真空泵抽气速率为18L／min、启停真空度为45～65kPa时，真空助力系统的综合性能最优。

The matching and optimizing of the parameters of the vacuum assisted brake system of electric vehicle were studied with an aim.The matching and calculation process was designed.A mathematical model for brake system was established.The matching optimization method of the parameters of vacuum assisted brake system was proposed for the start and stop vacuum degree,volume of vacuum tank and pumping speed,and etc.Taking an electric minibus for example,the minimum vacuum degree and the pumping speed that the electric vacuum pump must offer were calculated and matched.The relationship between the volume of vacuum tank and the pumping speed was analyzed.A model of simulation for vacuum assist brake system was set up to analyze the interplay of the start and stop vacuum degree,the pumping speed,working hours and energy consumption,and etc.The result shows that when the volume of vacuum tank is 5 L,the pumping speed is 18 L/min and the start and stop vacuum degree is 45 ~ 65 k Pa,the vacuum assist brake system is in the best overall performance.