Research On Inverter Control Based On DE-ELM Sliding Mode Variable Structure

Inverter is the core device of energy conversion and plays an irreplaceable role in energy storage,photovoltaic power generation and new energy vehicles.With the continuous iterative updating of energy technology,the inverter is directly facing the demand for upgrading in terms of power output quality.In order to deeply explore the potential of inverter efficiency improvement,it is of great significance to study more reliable and efficient inverter control strategies.In this thesis,a new sliding mode variable structure controller based on ELM and DE algorithm is designed for single-phase inverters,aiming at improving the output quality of inverter power.Firstly,according to the operation principle of the inverter,the internal relationship between the switching frequency and the AC output is analyzed,and the mathematical model of the full-bridge inverter is established.For the harmonic component that affects the performance of the inverter,a double closed-loop control strategy is designed,which uses PID control to regulate the current inner loop and sliding mode variable control to regulate the voltage outer loop.Aiming at the problems of sliding mode variable structure control and the defects of traditional exponential convergence observer,a sliding mode variable structure controller with limit ELM as disturbance observer is designed,and the design feasibility is proved by Lyapunov stability analysis.Secondly,in order to solve the problems of slow convergence speed and weak generalization ability of the limit ELM,the DE algorithm is used to optimize the input parameters and hidden layer bias of the limit ELM to further improve the convergence speed,stability and output dynamic quality of the sliding mode controller.Finally,in order to verify the actual usability of the design,a hardware experimental platform is built with DSP and inverter modules for experimental verification.Through the analysis of experimental data,it is concluded that the new sliding mode controller has greatly improved the output stability,output convergence speed and output waveform dynamic quality of the inverter,plays an practical role in improving the output quality of inverter.Aiming at the control output problem of single inverter,this thesis has carried out research on mathematical model building,sliding mode controller design,system feasibility analysis and physical verification,and finally innovatively designed a sliding mode controller based on DE-ELM,which has proved the effectiveness of the new controller in improving the efficiency of the inverter.