Research On Control Strategy Of Photovoltaic Energy Storage Grid-connected System Based On VSG

With the increasing global demand for energy,the continuous emergence of new energy gradually occupies an important position in the field of power generation.As the main structure of power generation technology and power transmission and conversion,the effective application of microgrid is of great significance to the promotion of alternative energy work.Among many distributed energy sources,solar power generation has become an important research object in various countries because of its unique advantages,and with the increasing of photovoltaic power generation capacity,The impact of grid-connected capacity on grid operation has become another problem to be solved.In this paper,the micro-source network composed of photovoltaic array is used as the main research subject,to analyze and model maximum power tracking technology and the principle of power generation.With the charge and discharge function of energy storage device,a complete and reliable DC side power generation structure is constructed.On this basis,the problems of traditional regulation mechanism in inverter control are discussed in detail,aimed at optimizing the control structure of optical storage micro-network system under VSG technology.In order to improve the response characteristics of power under parameter perturbation,the frequency difference and variation direction are collected and judged,to make the inertia coefficient change autonomously,the characteristics of large and small inertia in power-frequency response are fully utilized,and the dynamic regulation process of power system is refined.At the same time,the frequency deviation caused by the fluctuation of photovoltaic power generation is reduced by the secondary regulation of frequency,which makes the function of active power frequency control more complete and reliable.In addition,in order to ensure that the proposed control strategy can be effectively implemented in the optical storage system,the voltage regulation mode of the traditional excitation controller is replaced by the excellent adjustment ability of quasi-resonance,which maintains the stability of the voltage reference signal at the input of the inverter.Effectively enhance the immunity of the system.Finally,by integrating the above research results,the power distribution under the dual parallel system is analyzed in detail,and a phase-locked technique based on the DSOGI is adopted to realize the large reduction of disturbance components in the frequency extraction process,so as to improve the control accuracy of the system and optimize the output response curve.At last,by integrating theoretical analysis and mathematical model,a simulation structure is established under the MATLAB/SIMULINK platform,which verifies the active role of the proposed control strategy in energy management of photovoltaic energy storage system,adaptive inertia control of virtual synchronous generator,grid-connected pre-synchronization link,power distribution of dual parallel system,and proves the rationality and feasibility of the improved VSG technology in the operation of optical storage power grid-connected system.The paper has 70 figures,7 tables and 71 references.