一种电机驱动用大功率网侧变流系统研究

Study of High Power Grid-side Converter System for Motor Drives

提出了一种电机驱动用高性价比大功率网侧变流系统。主电路采用二极管整流器与PWM整流器并联,充分利用二极管整流器简单可靠、成本低,以及PWM整流器能量双向流动、功率因数高的优点,不仅能够省去传统电机驱动中的制动电阻,节约电能,还能提高交流系统功率因数。控制上通过对二极管整流器输出特性的研究,并调节PWM整流器输出特性,实现了PWM整流器与二极管整流器的协调工作。仿真和试验验证了主电路方案及控制方法的有效性。

A cost-effective and high power grid-side converter system for motor drives is proposed.The main circuit topology is based on PWM converter and diode rectifier.So the simplify and low-cost of the diode rectifier,as well as the bidirectional energy flow, high power factor and excellent controllability of PWM converter, can both be utilized.The braking resistors in traditional motor drive system are cancelled,so the regenerative energy will be saved.At the same time, the power factor of the whole system can also be improved.The output characteristic of the diode rectifiers is also studied.The effective parallel between PWM converter and diode rectifier is realized by controlling the PWM convert- er＇s output characteristic.The main circuit topology and control scheme are both verified by simulation and experiments.