Reliability Analysis Of Wind Power Cluster Planning Scheme With Monte Carlo

The rapid development of economy and technology,the high consumption of fossil energy and the proposal of sustainable development have brought more attention to renewable green energy such as wind energy.China has abundant wind energy resources,with the development of wind power technology and the increase of wind power installed capacity,more and more wind power clusters will emerge for grid connected operation.Due to the natural factors such as climate and topography,the randomness and volatility of wind power output will bring more uncertainty to the power grid and affect the reliability of the power system.In this paper,a nonsequential Monte Carlo sampling simulation is used to establish a reliability analysis model of the wind power cluster planning scheme.The uncertainty of the wind power is studied and the reliability of power system after wind power cluster grid connection is evaluated at the level of the grid connection planning of the wind power cluster.This paper mainly contributes the following aspects:(1)To establish wind speed probability distribution model,and generate correlated wind speeds.Combining the left and right half regions of different normal cloud models,the wind speed mixed half-cloud model is established to describe the asymmetry wind speed probability distribution,and the wind speed fitting degree,wind condition characteristics and wind energy resource indicators are calculated.According to historic wind speed data,the model can accurately reflect the distribution characteristics of wind speed in wind farms.According to the requirement of the traditional correlation matrix method that the probability distribution of wind speed should obey the normal distribution,the mixed half-cloud model of wind speed is introduced into the correlation matrix method.The results show,compared with the traditional sampling method,the correlated wind speed generated by the wind speed mixed half-cloud model is more consistent with the actual wind speed distribution,and is superior.(2)To establish wind farm output model,and study the factors that affect wind farm output.In order to establish a more realistic wind farm output model,and consider the impact of faults in the collection system components of the wind farm on the operating status of the wind turbine,reliability models for three types of current collection system components,equivalent wind turbines,circuit breakers and transformers are considered.Based on the consideration of wind speed randomness and wind turbine failure,the analysis of the output of two wind farms without considering the wind speed correlation between wind farms and the wind speed correlation,the wind farm output probability distribution under different correlation coefficients,and the effects of wake effects on the output power of wind farms under complex terrains and the impact of faults in the components of the current collection system on the number of normal working wind turbines.(3)To analyze the grid connection reliability of the wind power cluster planning scheme base on Monte Carlo.The reliability analysis model of the wind power cluster planning scheme is established,and the simulation analysis is performed from four aspects: the collection system components,the wind speed correlation,the wind power grid connection point,and the wind power replacement of conventional unit capacity.Cost coefficients are set based on the importance of the load point and the generation cost of conventional units and wind turbines,the load-cutting model is established with the minimum load loss and generation costs as the objective function and analyzing the impact of different wind power cluster grid-connected schemes on the reliability of power generation and transmission systems on the premise of economic considerations.The simulation results show that,when wind turbines replace conventional units,it will sacrifice the reliability of the system to bring economic benefits,the increase in the replacement capacity will accelerate the decline in reliability and the economic benefit will increase slowly.Different grid-connected points and different numbers of gridconnected points will affect the reliability of wind power grid-connection.The number of gridconnected nodes and grid-connected points is related to the selection of booster stations during planning,reliability analysis of different planning schemes is required to obtain the optimal grid-connected scheme.