针对不同类型电动汽车充电站的谐波问题,对不同类型电动汽车充电站的谐波抑制方法进行了研究,首先对电动汽车充电站谐波的产生原因进行了分析,然后通过PSCAD电力系统仿真软件分析了主流车载、非车载充电机产生的谐波情况,并研究了多台谐波含量高的非车载充电机共同作用时的谐波特点.针对非车载充电机存在的谐波问题,对改进整流环节主动治理和加入滤波器集中治理两类方法进行了研究.对增加不控整流脉波数、采用PWM整流方法的主动治理方法以及加入并联有源滤波装置的集中治理方法进行了仿真分析.比较了几种方法在仿真中的谐波治理效果,对治理效果好的并联有源滤波器方案进行了模拟负载试验.研究结果表明:并联型有源滤波器能够实时检测电动汽车充电站中谐波电流的变化,并输出补偿电流跟踪检测出的谐波电流;当充电站中谐波电流发生突变时,可以在几个工频周期内完成补偿,可以将谐波含量降低到2.73％,各次谐波含量中最高仅为0.69％,有效将谐波含量降低到国家标准之下.%Auning at the problems of harmonic currents generated by different electric charging station, the methods of harmonic suppression for different types of electric vehicle charging stations were studied. Firstly, the causes of the harmonics of the electric vehicle charging sta-tion were analyzed. Then, the harmonic of main vehicle charger and non-vehicle charger were simulated and analyzed, and the harmonic characteristics of the non-vehicle chargers with high harmonic content were studied. Active rectification of rectifying link and centralized con-trol of adding filter was put forward to solve the harmonic problem of non-vehicle charger. The performance of increase the number of uncon-trolled rectification pulse, the use of PWM rectifier active control and the use of shunt active power filter device for centralized management was evaluated through the simulation. Comparing harmonic control effect of several methods in the simulation, the experiments were made on this load with the parallel active power filter had good control effect. The results indicate that the shunt active filter can detect harmonic cur-rent changes of electric vehicle charging station in real-time and outputs the compensation current to track the detected reference current. When the harmonic current of the charging station mutates, the shant active power filter can complete compensation with in several operating frequency cycles. The content of harmonic can be reduced to 2. 73％, the highest content of each harmonic is only 0. 69％, and content of harmonic is effectively reduced to the national standard.
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