Design Of Micro Photovoltaic Inverter Based On Soft-switch Technology

In today’s society, green energy has paied more and more attentions, Photovoltaic inverter as one of the main equipment of using the solar energy has been developing rapidly. Micro inverter is different from the centralized photovoltaic power station which covers huge area, it has been widely concerned by the strong ability to resist local shadow, can be installed a distributed on the grid and other characteristics. This paper analyzed the structure of the micro inverter, adopted a new Boost half bridge topology and two-stage type, with isolation structure design scheme of micro photovoltaic grid inverter was designed.In this paper, the two-stage photovoltaic grid inverter’s core components is the DC/DC part which has carried on the thorough analysis and research. firstly, To Boost half bridge circuit as the research object, this paper analysed the working principle of topology, derivated and simulation validated the soft switch of theoretical, and designed the leakage inductance of the resonance magnetic integrated transformer,and the switching loss has been effectively reduced. Secondly, In order to improve the photoelectric conversion efficiency, the paper proposes a new MPPT control algorithm based on the analysis and comparison of four commonly used maximum power tracking method, On the dynamic response speed and steady-state accuracy have been improved dramatically. Then, the design is based Dead-Beat Control with voltage feed-forward compensation controller, it not only has a good dynamic performance just like dead-beat control algorithm, but also enhance the robustness of the system.Based on the system overall design scheme, finally, the paper gives the system the important parameter calculation and selection, and auxiliary circuit, control circuit and the software designs and choices.the paper simulation test the topology and control method, base on the results of the simulation, tested the DC/DC principle prototype theory verification experiment, the experimental results verify the feasibility and effectiveness of the proposed method in this paper.