Weak Grid Integrated PV Plant Design Considerations for Improved Voltage Stability

This paper discuss the detailed design considerations which needs to addressed for integrating PV plant into weak grid. Weak grid integration of PV plant results in temporary overvoltages (TOV) at the point of interconnection (POI) in the event of faults. Power flow equations are derived to show how low short circuit ratio (SCR) is responsible for temporary over-voltages at POI for a given PV plant parameters. Later, the PV plant parameters which needs to be revisited for avoiding the TOV at POI during low SCR conditions are addressed and necessary modifications are suggested. The proposed design considerations are validated by means of simulation results using PSS/E.