Modeling the output power of PV farms for power system adequacy assessment

This paper presents a method to model the expected output power of PV systems and to evaluate their effect on power system reliability. Grid level PV systems are usually constructed from a large number of electronic components and converters. Modeling of these systems in power system reliability is a complex task due to the dependency of the output power on an intermittent source (solar) and the availability of a large number of system components. An analytical method to construct a capacity outage probability table (COPT) that captures both the intermittency of the input source and component failures was proposed to model PV systems in power system adequacy assessment. The intermittency of the input source and component availabilities were modeled separately and then convolved to construct a single COPT. The resulted COPT can be viewed as a single PV system with multi-derated states. System reliability indices were evaluated using discrete convolution method. Monte Carlo simulation was used to validate the results of the proposed method. The proposed method was implemented on the IEEE-RTS and Roy Billinton test system (RBTS) with a wind farm of 30 MW. The obtained results were very close to those obtained using Monte Carlo simulation with less computation effort.