Research On Capacity Credit Of Large-scale Photovoltaic Station

Over the years,humans continue to expand efforts to protect the environment,promoting the increasing demand for clean energy,which makes the PV technology has been rapid development in our country,the proportion of installed capacity of PV power generation in the power system is increasing.Due to natural cause,the stochastic nature and the volatility of the SR will exert negative influences on PV system output;the uncertainty of PV system will also exert negative influences on the grid connected PV system and the influences can not be ignored with the increasing installed capacity of grid connected PV power generation.In order to ensure the safety and stable operation of grid connected PV system,the reliability and confidence capacity of PV system must be studied.Firstly,SR model,PV station output model and the energy storage system model are established.Based on historical data of the actual SR,applying the conversion method to calculate the equivalent inclination of PV panels of SR on the inclined plane.Secondly,a new synthetic model of SR analog series is established.In order to reflect the fluctuation characteristic,seasonal characteristic,weather characteristic and daily characteristic of SR,clustering SR data based on the original Markov chain model,generating a number of state transition matrices;simultaneously,fluctuation characteristic of SR is simulated to improve analog series generation process.Thirdly,the sequential Monte Carlo method is used to evaluate the reliability of the generation system with PV power station.The different influences on the reliability index caused by the application of different models of synthetic SR analog series,different capacity of PV power,different capacity of storage system are compared,to verify the validity of the SR synthesis based on improved Markov chain model,and study the influencing factors of the reliability level of the generation system with PV power station.Finally,the capacity credit of PV power station is studied based on the first three parts.Combined with sequential Monte Carlo simulation,the capacity credit of PV power station is calculated by secant method.Calculated capacity credibility of the application of different models of synthetic SR analog series are compared,and analyzed the different influences on capacity credit caused by the different equal reliability indexes as criterion and permeability.