Investigations On Harmonic Suppression Strategy For Doubly-fed Wind Generators Based On PI＿RC Controller

Due to the working conditions of the wind a large amount of wind motor under grid environment containing harmonic interference,at this point in the background of the power grid voltage harmonic distortion or grid voltage unbalance phenomenon,because the current wind power as the mainstream model of doubly-fed induction motor.Stator are connected directly or indirectly during the operation of power grid,to makc it running easily affected by power grid voltage,As a result,the doubly-fed wind motor can not operate safely and stably continuously,which further deteriorates the power generation quality of the motor and threatens the safe and stable operation of the motor.Therefore,under the background of more and more strict requirements on power quality of power grid criteria and power setting,it is of great practieal significance to study the new control strategy of doubly-fed wind generator to improve its adaptability to power grid distortion and improve the power quality of wind power.Based on the current control technology,the vector control for inverter control technology of the double-fed induction wind generator as the research object,based on network side converter power grid voltage orientation,machine side converter detailed mathematical model of stator flux as well as the harmonic power grid harmonic model of the doubly-fed fan when doubly-fed fan is power grid harmonic-voltage disturbance.5,7 limes Influence,rotor current waveform distortion,at the same time,the electromagnetic torque in the generator and dc bus voltage and stator output active power and reactive power arc volatile,this article is based on a complex current controller,repetitive controller design of repetitive control system is studied in endometrium coefficient,adjust the gain coefficient and oilier parameters effect the compensation performance and stability of the system.The harmonic distortion rates of stator current,rotor current,active power and other parameters using conventional PI control and PI＿RC controller under ideal and distorted power grids are compared and analyzed by using the complex controller in the current loop control of doubly fed wind turbine.The simulation results show that the control strategy designed for harmonic suppression can improve the operation ability of the doubly-fed wind generator in the distorted power grid and improve the output power quality.