A Paralleled Integrated Control Device of Squirrel-Cage Induction Wind Generator LVRT

Abstract

To minimize the influence of power grid with wind power generation resulted by voltage sags with short duration, a paralleled integrated control device of squirrel-cage induction wind generator LVRT (Low Voltage Ride Through) is proposed which adds paralleled module circuits to conventional wind generator. With closed-loop hysteresis current control based on instantaneous reactive power theory and rated voltage control, this device can achieve reactive power compensation in normal operation and voltage stability when voltage sags. Power produced by wind generator is consumed during the sag and wind power generation system is connected to grid all the time. Simulation models about the device were built based on PSCAD / EMTDC platform and the analysis verifies the device’s achievement of LVRT.