Modeling and assessment of PV solar plants for composite system reliability considering radiation variability and component availability

This paper presents a method to model the output power of large PV systems for composite system reliability assessment. Grid level PV systems are usually constructed from a large number of power electronic components and PV panels. Modeling of these systems in power system reliability is a complex task due to the dependency of the output power on the intermittent source (solar radiation) and the availability of a large number of system components. An analytical method to construct a capacity outage probability and frequency table (COPAFT) that captures both the intermittency of the input source and component failures is proposed to model PV systems. The intermittency of the input source and component availabilities are modeled separately and then convolved to construct a single COPAFT. The resulting model includes both probability and frequency distributions. The proposed method reduces the complexity of modeling and evaluating large PV systems for composite system reliability assessment. The method is demonstrated on IEEE Reliability Test System (IEEE RTS). Considering the PV farm location with a view to enhance system reliability, sensitivity study is conducted to measure the effect of the location of the PV farm on overall system reliability. The results confirm that connecting PV farms to the buses that are at a high risk enhances the overall system reliability.