Control of Wind Turbine Equipped with DFIG after Fault in Power Grid

grid connected wind turbine is daily increasing. a problem in power grid is grid faults.most problem is system stability after faults, also a probable problem of new energy sources in connection with grid is Islanding due to faults.in this condition loading mismatch between generation and load ‏consumption in isolated part of system can cause voltage and frequency cross it’s allowable limit.too in the case of over generation rotor will accelerate.so these lead to turbine interruption.in this paper wind turbine equipped with doubly fed induction generator is controlled for uninterrupted operation during fault to achieve more stability and rapid voltage recovery. Authority of DFIG grid side converter and Dstatcom effect after three phase short circuit fault are compared. results shows that with combination Dstatcom with grid side converter, voltage regulation in normal operation is beter.also after a fault more voltage stability and rather voltage recovery is achieved.too a suitable control will be presented for sake that wind turbine be able under Islanding operation to feeding local load at rated voltage and rated frequency.ability of control strategy in Islanding operation is investigated and simulation results Illustrate control strategy ability.