燃料电池混合动力系统总线电压对电机转矩及效率的影响

为评价总线电压对电机转矩以及效率的影响,在动态测功机试验台架上设计相应的试验,测量总线电压在400~455 V之间变化时某三相异步感应电机的输出转矩和效率。结果表明,在电机低效率区域,电机效率受总线电压影响较大。电机输出转矩相对于目标转矩有平均0.5 s的延时,在高总线电压、高电机转速区域,电机控制器启动自保护功能,输出转矩远小于目标转矩。中国城市公交典型工况测试表明,对经济性影响最大的前80%的电机工况点主要分布于受总线电压变化影响较小的高效率区,在城市公交工况下对电机效率的粗略分析可以忽略总线电压的变化。

Influence of Bus Voltage on Motor Torque and Efficiency in Fuel Cell Hybrid Electric Vehicle

In order to evaluate the influence of bus voltage on motor torque and efficiency,bench experiments were designed on a dynamic dynamometer.The torque and efficiency of three-phase asynchronous induction motor were measured with the bus voltage changing between 400 V and 455 V.Results show that(1) the motor efficiency is mainly affected by the bus voltage in low-efficiency area,actual motor torque has an average delay time of 0.5 sec compared to the target torque command;(2) actual torque is lower than target torque in high-bus voltage and high-motor speed range because of self-protection of the motor controller.Results in "China typical city bus cycle" testing shows that the working points are mainly distributed in the high efficiency area which is affected by bus voltage slightly.As a result,the influence of bus voltage on motor efficiency could be ignored in city bus cycle analysis.