Allocation Schemes Research Of UPFC Based On The Multi-scenario With Different Weight Coefficients And Multiple-target Optimization In The Wind Power Integrated System

With the rapid development of the world economy,renewable clean energy is an important part of improving energy structure and relieving environmental pressure.Since wind power generation has the characteristics of randomness,intermittency and volatility,it is necessary to consider the fact that the two-way randomness of wind power output and load will cause rather big uncertainty of the power grid flows in the research of wind power grid,and it is easy to cause voltage instability and transmission power overload.Unified power flow controller(UPFC)can greatly enhance the safety and economy of wind power grid system by controlling line power flow and stabilizing node voltage.Most of the existing UPFC configuration methods fail to fully consider the global optimization of power system in the process of UPFC optimal configuration,the uncertainty of system operation scenario,and the difference of index weights of multiple optimization objectives in different scenarios.In view of the uncertainty of wind power grid-connected system,considering the time series correlation between wind power output and load,this paper uses K-means clustering method to partition the scene of wind power output-load sequence,and describes the operation mode of wind power grid-connected system accurately.This paper firstly considers the problem of network congestion in power system,the optimal configuration model of UPFC based on multi-scenario analysis and with the objective of grooming power network blocking is established,and the improved genetic algorithm is used to calculate the optimal configurati.on model of UPFC.The comparison between the optimal configuration scheme and the optimal configuration scheme considering only a single scenario proves the necessity of studying the uncertainty of power system operation mode when studying the UPFC configuration problem.In this paper,considering the safety and economy of wind power grid-connected system,the time series correlation between wind power output and load,and the difference of index weights under different scenarios,a multi-objective optimal configuration model of UPFC based on multi-scene variable weight is established.The optimization model of UPFC multi-scene variable weight multi-objective configuration with compensation of power network loss,voltage offset and load balance,and UPFC installation cost as the optimization target is established.The improved NSGA-II algorithm is used to optimize the installation number,location and capacity of UPFC,and the multi-scene entropy weight-analytic hierarchy process(AHP)is proposed to sort the Pareto solution set,and the optimal scheme of UPFC configuration is obtained.The simulation calculation of IEEE-30 node system verifies the correctness and validity of the model and algorithm.