effects of soil ionization and lightning impulse corona on lightning current strike

With the new structural changes of power system that has emerged in recent years, which makes manufacturing units transmit more and more electrical power from the transmission lines, it is expected that a wider voltage collapse in the power systems happens. in this paper, a new pidbased control method was used that provides a pccvoltage feedback control to increase reactive power from windturbine equipped with a doublyfed induction generator (dfig) at high voltage drop. the proposed method is an improved control scheme for voltage collapse, by which a part of the wind energy that causes a network failure is temporarily stored in the rotor energy and the remained energy is kept until dc voltage and rotor current are in the hazardous parts. the purpose of the rotor side controller is to independently determine the stator active and reactive power, which the control of the reactive power using the rotor side converter can cause the stator voltage to remain constant in the desired range. the accuracy and performance of the proposed method were confirmed by simulating a typical power system, in the matlab/simulink environment.