Optimal tuning of governors on synchronous generators in a multi-area power system with a large photovoltaic plant

Abstract

The integration of renewables, such as solar and wind power, introduces new challenges for existing multi-area power system operations. These variable generation sources are transforming the grid into a more dynamic system which significantly affects real-time operation. With dynamic generation, supply and demand will deviate frequently over time causing severe frequency fluctuations. The generators on the grid must respond rapidly to these fluctuations in order to stabilize the system and ultimately return to nominal frequency. In this paper, a 210 MW photovoltaic (PV) plant is integrated into a two-area four-machine power system. Due to the output variations of the PV plant, especially during cloudy conditions, the system frequency will significantly fluctuate. The objective of this paper is the optimal tuning of governors on synchronous generators in order to damp and mitigate frequency deviations as fast as possible. The governor parameters are tuned using a heuristic optimization method to provide the least number of frequency events and minimum frequency deviation with varying penetration levels of PV power. With optimally tuned governor parameters, a multi-area power system can operate reliably while maximizing the utilization of clean power generation sources.