Research On Predictive Direct Power Control Of Voltage Type Grid-connected Inverter Based On Model Reference Adaptive

Energy and environmental issues are hot issues that humans care about.Nowadays,human beings are facing energy crisis and environmental pollution.The development of renewable energy and the change of the energy structure are the key to solving the problem.With the improvement of science and technology and economic development,photovoltaic power generation has gradually emerged as an effective way of power generation that is widely used today.As the key hub of renewable energy and public power grid,grid-connected inverters play an irreplaceable role in realizing high-efficiency power conversion.Therefore,it is of great significance to study the high-performance control strategies of grid-connected inverters.In this paper,the commonly used direct power control methods of three-phase voltage grid-connected inverters are studied.First,a mathematical model of the grid-connected inverter is established,and the models and performances of feedforward decoupling direct power control and hysteresis direct power control based on instantaneous power theory are analyzed.Then the control principle and control performance of model predictive control(MPC)are combined,aiming at the output error and current quality of the traditional direct power control strategy,the predictive direct power control(P-DPC)strategy is proposed,and theoretical analysis and simulation research are carried out,the influence of line parameter deviation on the control effect of predictive direct power control strategy is studied in detail.The control system has weak robustness.Finally,to further improve the robustness of the strategy,model reference adaptive control(MRAC)is introduced to reduce the sensitivity of the control system to system model parameters and improve the adaptability of the control system to the system model.The structure and parameters of the control system are analyzed,designed and calculated in detail.Using the stability method of Lyapunov theory to compare and study the non-adaptive model reference prediction direct power control strategy and the adaptive model reference prediction direct power control strategy,it is proved that the system has the stability of error convergence and the latter has better parameter adaptability,good tracking performance and strong robustness to parameter uncertainty.MATLAB/Simulink simulation software is used in this paper to carry out detailed simulation research on the predictive direct power control system of voltage-type grid-connected inverter based on model reference adaptive,and a d SPACE experimental platform is built for experimental analysis.Simulation and experimental results verify the effectiveness and feasibility of the proposed control strategy in improving the control effect and enhancing the robustness.