Research On Predictive Two-objective Control Strategy Of Three-phase Grid Connected Model

With the rapid development of new energy grid-connected power generation systems such as wind power generation,photovoltaic power generation and tidal power generation,the trend of research ingenuity and application of new energy power generation technology is becoming more and more obvious,which brings great opportunities for the development of inverter application.With the rapid development of DSP technology and microprocessor,the application of finite control set model predictive control technology(FCS-MPC)in grid-connected inverters has gradually become a hot research topic.Model predictive control(MPC)is a kind of computer control algorithm,which has the unique advantages of easy to increase constraints,fast dynamic response and eliminating PWM modulation technology.The traditional model prediction control algorithm has the problem of conservatism,low static tracking accuracy of electrical flow and high rate of current distortion.Based on the traditional model prediction control strategy,the paper makes a simulation,comparative analysis and research on several existing model prediction control strategies,combines the advantages of the model prediction listed,and carries out the research work of the three-phase grid-connected model prediction two-objective control strategy.Firstly,through the three-phase grid-connected inverter model’s topology and working principle,the selection of circuit parameters is analyzed in combination with mathematical model.Then the control principle and design idea of the traditional current model prediction control strategy of the three-phase grid-connected inverter are summarized,and the two-objective control idea of the traditional model prediction current control strategy is simulated and verified.Secondly,the paper discusses the existing model prediction control technology strategies and compares it with the simulation.Based on the advantages and disadvantages of the existing model prediction control technology,a model prediction two-goal optimization control strategy is designed by analyzing the current tracking control,reducing the switching frequency method and simplifying the operation.The main design idea and method of optimizing the control strategy is to apply the vector angle compensation method on the basis of the two-step prediction method to make system delay error compensation,make up for the conservatism of the traditional model prediction control strategy with long-range optimization,and reduce the switching frequency by using the adjacent voltage prediction method.Finally,the value function is optimized,compared with the traditional model to predict the two-target control strategy,the optimization control strategy can improve the system current tracking accuracy and reduce the effect of the switching frequency,so as to solve the traditional model prediction two-target control strategy itself has conservative,dynamic static tracking accuracy is low,high current distortion rate.Finally,through simulation and experiments,the effectiveness and feasibility of control strategy are verified.There are 72 figures and 4 tables.