Research On The Control Strategy Of Microgrid Inverters

At present,the traditional power generation technology is no longer able to meet the needs of development.Micro-power grid is[1]a combination of a variety of distributed power supply,which can be coordinated control of different power modes and has two operating modes of independent and connected.However,different types of micro-power and energy storage equipment in fact rely on micro-power inverter to work in the micro-grid,thus,the study of micro-power iinverter[2]is very meaningful because of its critical role in micro-power integrated devices.This paper expounds the basic principle of control strategy:Constant Power control,Droop control and Constant voltage/Constant frequency control,and selects the droop control in this paper.Aiming at the problem of harmonic content and loss in the process of system realization.This paper studies the classical three-level SVPWM algorithm and applies it to the system.At the same time,the model is built and simulated on the simulation platform.According to the analysis,the loss is low,the harmonic content is less,and the output waveform is smoother.The switching of two modes of grid-connected and Gudao can be controlled by droop characteristic to allocate power,to maintain power balance,and droop control should be directly used for power control,it needs to add a PI regulator in the grid-connected mode.For the regulation of PI parameters,the general method is to use fuzzy control,but because fuzzy rules have a relatively large randomness,so the precise control method of mathematical model and control of modern control methods,the effect is not very ideal,in the continuous study of scholars,At present,it is very popular in the industrial field to use intelligent method to adjust pi parameters.Therefore,the paper designs the fuzzy neural network controller to adjust the pi parameters in the voltage outer loop.At the same time,based on the Matlab/Simulink simulation platform,the system simulation model is established,and the simulation experiment is compared and analyzed.The results show that the neural network fuzzy algorithm has better regulation,responsiveness and stability,and is more convenient and efficient,and also improves the control effect of the micro-grid.