The Research Of Single-phase Grid Inverter Based On The Virtual Space Vector

With the reduction of fossil energy reserves and the aggravation of environmental pollution, more and more people pay attention to the new energy power generation technology, and the solar energy as a kind of green energy has been favored by people. Photovoltaic grid connected inverter as the key device of photovoltaic power generation, to achieve the function of DC to AC conversion and is synchronized with the grid and the maximum power point tracking, so research on photovoltaic grid connected inverter to solve the world’s energy crisis has important significance. The main contents of this paper are as follows:1. Analysis of the photovoltaic power generation at home and abroad development situation and the application prospect, expounds the grid connected power system types, system structure and grid standards, introduced the working principle of photovoltaic grid connected generation system, photovoltaic inverter topology, modulation method and system control strategy. Selection of single-phase full bridge inverter topology, using frequency modulation method.2. The main structure of the single-phase grid connected inverter is analyzed, and the mathematical model is established and given the grid type single-phase PV inverter virtual space vector control strategy, using the Hilbert transform method to construct the virtual vector,and described the implementation process of single phase grid connected inverter based on virtual space vector strategy.3.Using Matlab/Simulink tool to build grid type closed loop simulation model of single-phase photovoltaic inverter, using PI regulator, coordinate transformation, and the virtual space vector method, a simulation model based on the simulation results are obtained.4.Expounds the single-phase grid inverter hardware and software design thought, system design of main circuit and drive circuit is given and the software design flow chart. Make prototype, and get the result of the experiment, the experiment shows that the inverter prototype work reliable, stable, and has good load capacity and output characteristics.