Wind power generation system with constant speed constant frequency wind turbine system and VSCF wind turbine system two categories. Constant speed constant frequency wind power systems typically use synchronous motors or squirrel-cage induction motor as a generator, fixed pitch stall controlled wind turbine pressurized solar water  speed maintained at a constant value then ensure the frequency of the output voltage of the generator terminal the amplitude constant, and its operating range is relatively narrow, only under certain wind speed to capture wind power generation efficiency is low. VSCF wind power systems generally use a permanent magnet synchronous motors or double-fed motor as a generator, pitch control wind wheel run in accordance with the best efficiency of the entire system within a wide speed range, current wind power technology direction of development. Speed ??range for the fan, it is generally in the range of 50% to 150% of the synchronous speed, if ordinary squirrel-cage induction motor system or the system of permanent magnet synchronous motor, inverter capacity requirements with drag generator capacity rather, it is very uneconomical. Doubly fed induction wind power system stator and grid directly connected to the rotor and the power converter is connected, only through the power of the converter slip power the various transmission efficiency is relatively high, the structure for the governor a wide range of wind power generation system, especially, in the capacity of wind power generation system.

This article from the variable speed constant frequency induction wind system topology and its control technology of inverter technology in wind power are reviewed to reflect the frequency conversion technology in the development of wind power.

Second, the VSCF induction wind power system topology

Wound induction motor as a generator and its rotor current control is one of the main form of VSCF induction wind power generation system. The main topology including AC excitation control, rotor chopper, trimming, and combined with a hybrid structure evolved by the two china solar water heater.