Improving Distribution System Voltage Stability Using DFIG-Based Wind Farms

Abstract

This study investigates the impact of doubly fed induction generator (DFIG)-based wind farms on distribution system voltage stability. A modified 61-bus distribution network is simulated in PowerWorld Simulator using the voltage collapse proximity indicator (VCPI) to evaluate voltage stability under different wind penetration levels. A method for calculating the voltage collapse proximity indicator when reactive power limitation of wind generators is taken into consideration and a system reaches maximum loading, was developed in our previous work. DFIG-based wind generation is connected at a strong bus and operated in voltage-controlled mode. Simulation results for 10%, 20% and 30% wind penetration levels show that the doubly fed induction generator improves the distribution system voltage stability and increases the voltage collapse margin. The improvement becomes more significant as wind penetration increases, with the 30% case providing the best performance. These results demonstrate the potential of DFIG-based wind farms to enhance voltage stability in distribution network.