Research on Zero-Voltage Ride Through Control Strategy of Doubly Fed Wind Turbine

With the rapid increase in proportion of installed wind power capacity total grid capacity, state has put forward higher and requirements for integration into grid, among which most difficult requirement is zero-voltage ride through (ZVRT) capability turbine. When voltage drops deeply, a series transient processes, such as serious overvoltage, overcurrent, or speed rise, will occur motor, seriously endanger safe operation turbine itself its control system, cause large-scale off-grid accident generator. Therefore, it great significance to improve uninterrupted ability Doubly fed induction generator (DFIG) can achieve best energy tracking wide range advantage flexible regulation. It widely used at present, but sensitive voltage. In current study, DFIG taken research object. The process during fault analyzed detail. mechanism rotor overcurrent DC bus overvoltage studied. Additionally, simulation model built DIgSILENT. active crowbar hardware protection circuit side turbine, extended observer terminal sliding mode are added converter control. Through cooperative technology, be suppressed realize ride-through doubly ensure stable farm. Finally, results presented verify theoretical analysis proposed strategy.