Stochastic processes in a grid-connected three-phase photovoltaic system

With appropriate control algorithms, grid-connected photovoltaic (PV) systems can provide real and reactive power to meet power system needs. However, the intermittency of solar irradiance and the stochastic nature of reactive power demand affect the dynamic performance of these systems. This paper presents a method for stochastic modeling and simulation of grid-connected three-phase photovoltaic systems. The state variables of concern are the real and reactive power delivered to the grid, and the line currents. The objective of this work is to model the statistics of the reactive power demand as a linear stochastic differential equation driven by a wiener process, model the solar irradiance and temperature as random variables, develop a dynamic performance stochastic model of the entire system, and ascertain the time evolution of the first and second moments of the state variables.