Control strategy of doubly-fed wind generation system for power grid fault

A fault control strategy of DFIG is proposed based on the active,reactive control of the decoupling for VSCF doubly-fed wind power generation system.The model is set up in MATLAB/SIMULINK.The simulation results verify the correctness of control strategy.In conventional case,the active of DFIG rotor side uses the MPPT control and the reactive uses the rated power factor control.It can get the largest wind energy utilization efficiency and better power factor,but it can't when power grid fault occurred.And the power grid voltage and frequency will fluctuate.So the MPPT control and the rated power factor control switch to frequency control and voltage control strategy when power grid fault occured,by controlling the active current and reactive current component to reduce or increase active and reactive power output,to maintain the system frequency and voltage stability.The model of controlling under fault conditions is set up.The simulation is running in two conditions such as single-phase grounding and two-phase short-circuit.The results of simulation show the correctness of fault control strategy.The stability of wind power system is enhanced under fault conditions.