State Evaluation And Maintenance Strategy Analysis Of Photovoltaic Power Plants

Solar energy is a widely distributed and abundant clean energy source and is an internationally recognized ideal alternative energy source.In recent years,the cost of photovoltaic modules and other components of power plants has decreased,and photovoltaic power generation technology has become increasingly sophisti cated.Countries have begun to vigorously develop and utilize solar power to build photovoltaic power plants.Studying the state assessment and maintenance strategy of photovoltaic power plants is of great significance for more economical utilization of solar energy resources and optimization of the operation of photovoltaic power plants.This paper proposes a state evaluation model and maintenance strategy optimization method for photovoltaic power plants.The main work and achievements are as follows:1)State evaluation model of photovoltaic array: The characteristics of the maximum power point voltage,current and power of the photovoltaic array under different operating conditions are analyzed,and the indicators of the photovoltaic array state evaluation model are determined,and the horizontal irradiance and ambient temperature are considered.The influence of the indicator is determined by curve fitting to determine the range of values of the indicators.Finally,the fuzzy comprehensive evaluation is used to evaluate the state,and the state evaluation result of the photovoltaic array is obtained.2)Maintenance strategy of photovoltaic power plant based on component-system classification optimization: first predict the state of each component according to the Markov chain,calculate the component failure risk loss according to the state prediction result,and determine the most economical preventive maintenance time of each component according to the average maintenance cost analysis in the component level optimization stage.The collection of maintenance strategies for each component is obtained.In the system-level optimization phase,based on the maintenance cost correlation between the components and the structural dependence,the time threshold for the joint maintenance of the components is determined,and the optimal maintenance strategy of the system is determined,so that the maintenance between the components is coordinated,thereby minimizing maintenance cost and reduce system downtime losses.3)On the basis of the time-varying characteristics of the component failure rate,the maintenance strategy of the photovoltaic plant is carried out throughout the life cycle: The normal working rate of the photovoltaic array which is a multi-state component is statistically analyzed,and the influence of the failure rate on the operating state of the components is analyzed,then the maintenance strategy of the photovoltaic power station is optimized.