Research On Optimal Configuration Of Independent Microgrid Considering Voltage Opportunity Constraints

The independent microgrid is generally used in remote areas or islands away from the main network.It can effectively solve the power supply problem by using renewable energy such as local solar energy and wind energy,and has multiple meanings such as economy,environmental protection and people’s livelihood.The independent microgrid lacks large grid support,and the voltage regulation capability and voltage stability are relatively weak.It is necessary to consider voltage constraints in the microgrid planning.Therefore,the scientific planning of microgrid equipment access capacity and location,in pursuit of voltage deviation requirements to pursue the lowest total cost,is an important means to ensure the rational investment,economic operation and reliable power supply of microgrid.In order to consider the influence of uncertain factors in the microgrid optimization configuration process,this paper uses the probabilistic statistical method to analyze the stochastic characteristics of distributed power and load.Firstly,the probability distribution model of wind speed,solar radiance and load is established.Using the Latin hypercube sampling-Monte Carlo simulation(LHS-MCS)to obtain power samples of randomly distributed wind turbines,photovoltaics and loads.And introduce a battery steady state model for discrete calculation analysis.Combine the wind,solar radiance and load power samples to determine the system operation strategy including the wind abandonment and the sunshine rejection strategy,providing a data foundation for the microgrid optimal configuration model solution.Based on the voltage opportunity constrained programming method,the voltage qualification rate and power supply reliability are taken as the main constraints,and the configuration model with the micro-power installation capacity and position as the optimization variables is established with the goal of minimum system cost.The random weight particle swarm optimization(RWPSO)algorithm is used to solve the problem.The wind power load sample generated by LHS-MCS is substituted into the deterministic power flow algorithm to realize the random power flow calculation,based on the established microgrid operation.The strategy calculates the constraints and fitness,and obtains the optimal configuration scheme by global optimization through the RWPSO algorithm.The microgrid PSCAD simulation of the corresponding configuration scheme is built.The wind speed,illumination,load data and battery SOC status are used as input parameters on each day of the typical day.The microgrid simulation is run in hours,and the running results of various indicators of the system are obtained and analyzed.At the same time,select typical working conditions and different disturbances for multi-scenario simulation,observe the dynamic response process of each state quantity of the system,analyze the dynamic performance of the microgrid optimal configuration scheme,and verify the feasibility of the configuration scheme.