Research Of Load Frequency Control For Multi-Area Interconnected Power System

The main task of power system is to guarantee the relative stability of frequency and voltage.With the continuous improvement of the demand for power in modern society,the scale of the interconnected power network is becoming larger and larger,and the problem of its stability has been greatly changed.For multi area interconnected power system,not only should consider the power system frequency control,but also pay attention to the contact line between the regional and regional switching power control,which is to the regional power system for load frequency control when to keep it safe,reliable running.In order to solve these problems,the following research is done in this thesis.Firstly,the thesis analyzed the problem of the load frequency control system,then analyzed and discussed the style,pattern and method of load frequency control.Through the analysis,the decentralized control style and TBC control pattern of the interconnected load frequency control system is determined.Then,modeling the load frequency control system.It analyzed the problems that need to be considered in the modeling,then analyzed and modeled the related components of the load frequency control system.Subsequently,analyzed and studied the DC power modulation of HVDC transmission,and established the model of AC/DC load frequency control system.Then,the control method of the load frequency control system is studied in detail.The interconnection of multi-area power grid has the characteristics of nonlinear,time-varying and parameter uncertainty,strong coupling and so on.Fuzzy control has strong uncertainty knowledge expression and logical reasoning ability,it can solve the problem of interconnected power network very well.This thesis adopted two intelligent load frequency control methods.One is based on the OBC-PSO algorithm for optimizing the load frequency control of fuzzy PID,which use OBC-PSO to optimize the fuzzy universe to enable the controller to have self-learning,global optimization and ability to handle complex system.The other is fuzzy RBF neural network,the Fuzzy RBF not only has the advantages of fuzzy control but also the neural network self-learning of the advantages.In this thesis,the sample data obtained from the output of the optimal and the optimal output of the first method.The performance of the system will be improved through training RBF by the sample data.By Matlab/Simulink simulation to verify the proposed method.Simulation results show that the two methods used in load frequency control has strong anti-interference ability,adaptive,robust nature.At last,making a summary of all work,and pointing out the problems and shortcomings,then putting forward the problems to be resolved in the future.