Voltage Stability Analysis of Large Scale PV Plant Reactive Power Control Methods

Abstract

The increasing integration of photovoltaic (PV) plants in conventional power systems has led to the need to examine the effects of these plants on the system dynamics. In this study, a well-known IEEE-9 bus power system is modified by integrating PV plant in DigSilent Powerfactory environment. Then, 3 transient cases are tested by using PV plant control units designed by Western Electricity Coordinating Council (WECC). The effect of load and line transient disconnections and 3-phase short circuit fault on modified power system are investigated as case-I, case-II, and case-III, respectively. In all cases, two sub-cases are considered according to the location. As a result, comparison of PV system reactive power control methods (RPCM) is analyzed in terms of voltage stability in these 3 cases.