双馈风电机转子侧变换器的容错控制研究

Study on Fault Tolerant Control of Rotor Side Converter in Doubly-fed Induction Generator

在双馈风力发电系统中,变换器是重要的组成部分,它的稳定运行给风电机转子提供可靠的交流励磁电源,通过对变换器的控制,实现对双馈电机有功和无功的解耦控制。为了提高双馈风电机中变换器运行的可靠性,把开关冗余变换器应用到双馈风电机容错控制中。在三相变换器其中一相故障的情况下,通过设计硬件电路,使得故障的一相用2个串联的电容代替,构成新的三相变换器,在α-β坐标系下,推导出三相四开关的空间电压矢量算法,最后通过故障模式下的变换器输出的交流励磁电流进行仿真验证。

The converter is an important pall of doubly-fed induction generator （DFIG）. It＇s able to provide reliable AC excitation power supply for the rotor of induction generator in steady operation. The decoupling control of active power and reactive power is implemented by controlling the converter. To improve the reliability of the converter in DFIG, the switch redundancy converter is applied in the fault tolerant control of DFIG. When one phase is broken down, the fault phase is replaced by two series-connected capacitors by designing hardware circuit, and the new converter is composed. The space voltage vector method for the converter with three-phase four-switch is derived based on the α-β reference frame. At last, the paper conducts a simulation and verification of the fault tolerant control through the ae excitation current output of the converter with faults.