Modeling a Solar Power Plant with Regard to Changes in Environmental Parameters

Abstract

An approach is described for modeling the operating parameters of photovoltaic converters with regard to changes in natural and climatic conditions. A review of frequently used approaches to modeling photovoltaic converters in problems of optimal unit commitment is presented. Based on the basic provisions of energy system studies, a number of requirements for the proposed approach were formed. An algorithm for calculating the operating parameters of photovoltaic converters, such as output current, voltage, active power, efficiency, and operating temperature, is described. In calculating the operating temperature of the converter, the Koehl correlation coefficients are used to account for additional cooling due to on-ground wind flow. The study also presents the numerical values of the necessary modeling coefficients. As an example, the village of Innyaly (Republic of Yakutia, Lensk raion) was chosen with a solar power plant of a 40-kW capacity planned for building by 2022. For the territory under consideration, a data set of a typical meteorological year was formed using the Local Analysis of Environmental Parameters and Solar Radiation software and computing complex developed at the ESI SB RAS. When forming a typical meteorological year, retrospective natural and climatic data of the FM 12 Synop format from the nearest weather station were used. The modeling results demonstrated the adequacy of the proposed approach. For example, when the level of solar radiation changes, the output current and active power change significantly, while no voltage change is practically observed. At the same time, a decrease in the operating temperature of the photovoltaic converter increases both efficiency and voltage. The modeled operating parameters are consistent with real data obtained by the Australian Solar Center at the power plant in the city of Alice Springs. The proposed approach can be applied to solve problems of optimal unit commitment, adequacy, calculation of economic efficiency, and other energy system parameters.