Effect of central station photovoltaic plant on power system security

The value of photovoltaic (PV) plants to electric utilities is investigated under constraints of power system security. It is suggested that the generally adopted methods of analysis for determining the capacity credit, energy displacement, and production cost savings due to the PV plants have neglected the adverse conditions that may arise out of a random preselection of a substation where PV power is injected into the system. The author presents an extensive approach to determining the realistic value of a PV plant to the utility. The method consists of using a power flow algorithm to determine system conditions under specific load scenarios. Identification of bus voltage violations and branch overloads is an integral part of the method. The location of the substation where PV is included is very important. Determination of system behavior under contingency conditions with and without PV is also investigated