Fast active power output reduction system of doubly-fed induction generator and method thereof

An FPR system, comprising a pitch servo system, a DC-link and a rotor-side converter (RSC) and a grid-side converter (GSC) connected in parallel across the two poles of the DC-link;

• and further comprising a DC chopper circuit, which includes a dump resistor and a fully controlled power switching device;
• the dump resistor and the fully controlled power switching device being first connected in series and then connected to the positive and negative poles of the DC-link, respectively;
• the fully controlled power switching device being driven by a power switching device driver;
• the power switching device driver comprising a first inverting adder, a first PI controller and a PWM modem;
• positive and negative input ends of the first inverting adder receiving real-time DC-link voltage signal and its threshold value respectively, and the output end of the first inverting adder being connected to an input end of the first PI controller;
• an output end of the first PI controller being connected to an input end of the PWM modem;
• and the PWM modem out putting the pulse signal to the control end of the fully controlled power switching device.