Power Quality Improvement of Grid Connected Wind Farms through Voltage Restoration Using Dynamic Voltage Restorer

Abstract

Increasing sensitivity of the loads with respect to power quality has gained the interest of power system analysis and power quality improvement techniques. The voltage sags or swells which are characterized by rms voltage variations outside the normal operating range of voltages due to faults may lead to improper disconnection of wind turbines. This paper deals with the effective voltage sag/swell mitigation using Dynamic Voltage Restorer (DVR), to regulate the terminal voltage of the wind farm. The DVR utilizes a feed forward vector control based algorithm to generate the PWM based firing signals for injecting appropriate compensation voltages. The actual wind farm field data of the voltage sag and swell events during fault conditions are re- created using MATLAB/Simulink and restored by employing DVR. The simulation results are shown to verify the operation of DVR during balanced voltage sag and swell conditions.