Optimization Research On Grid-connected Inverter With Magnetic Integrated Filter

With the shortage of globalized stone energy and global warming,economic,clean and renewable new energy has been widely concerned by governments and industry as an effective means to solve these problems.The use of renewable energy for grid-connected power generation is the most worthwhile research today.Grid-connected inverter is the main equipment that connects new energy power generation equipment directly to the power grid.Its performance is directly related to the stability of power grid operation and power quality.Therefore,it is of great significance to carry out the design and analysis of grid-connected inverters.An improved LCL filter is designed.In the analysis of the LCL filter structure,the magnetic integration method is used to replace the inductance on the filter,the volume and weight are reduced,the LCL filter structure is improved,and the corresponding filter parameters are designed.A three-phase magnetic integrated inductor is designed.The magnetic flux path of the inductor is analyzed by Maxwell simulation software.In order to prevent magnetic saturation,the maximum effective magnetic permeability is calculated by simulation to obtain the optimal effective permeability,and then the gas is selected.The position and length of the gap are used to optimize the inductance.Select the core,design winding windings,calculate winding losses and core losses.The final design of the magnetic integrated inductor is only 15.3% of the traditional inductor,the weight is only 16.6% of the traditional inductor,and the filtering performance is better than the traditional inductor.The LCL filter three-phase grid-connected inverter simulation model is constructed.On the Matlab/Simulink platform,the dynamic response simulation of the three-phase grid-connected inverter system is carried out.The simulation experiment of LCL filter and magnetic integrated LCL filter is compared and verified.The effectiveness of the design control scheme and system parameters.Using the SKM75GB12 V model IGBT switch tube,a 1kW/220 V LCL filter three-phase grid-connected inverter experimental prototype was built.The main circuit of the inverter,the switch tube drive circuit,the magnetic integrated inductor and other peripheral circuits are designed respectively to verify the performance and system stability of the output filter.