Primary strategy by deloaded Permanent magnet wind generator

Traditional winds turbine cannot support the frequency stability of the island grid, when using maximum power point tracking (MPPT) control strategy. This paper proposed a method that the load of the grouped wind generators control strategy, control the speed of the rotor to over-speed control condition, achieving the deloaded generator operation when the wind speed is under rate wind speed. When the wind speed is higher than the rated wind speed, combined invariable pitch control with over-speed control to achieve the load reduction. This method provides active backup for the generator in the frequency stability regulation of the island system. Simulation results showed that the load shedding control reduce the fluctuation of the system frequency and stabilized the island operation when the load increasing rapidly.