A ten-switch clamp type three-phase non-isolated photovoltaic inverter topology

Abstract

The invention relates to a topological structure of a ten-switch clamp type three-phase non-isolated photovoltaic inverter, which includes a three-phase six-switch tube, a three-phase output filter, a three-phase load and a three-phase clamp circuit. The three-phase clamp circuit includes The first, second and third DC capacitors and the upper and lower DC switch tubes and the upper and lower clamp switch tubes, the positive pole of the first DC capacitor and the drain pole of the upper DC switch tube are respectively connected to the positive pole of the solar cell, and the third The negative pole of the DC capacitor and the source pole of the lower DC switching tube are respectively connected to the negative pole of the solar cell, the source poles of the upper clamping switching tube are respectively connected to the negative pole of the first DC capacitor and the positive pole of the second DC capacitor, and the lower clamping switching tube is connected to the positive pole of the second DC capacitor. The drains of the upper DC switching tube are connected to the negative pole of the second DC capacitor and the positive pole of the third DC capacitor, the source of the upper DC switching tube is connected to the drain of the upper clamping switching tube, and the drain of the lower DC switching tube is connected to the lower clamping switch. The source of the tube is connected. The invention has the advantage of effectively suppressing common mode leakage current and ground leakage current.

Description

technical field [0001] The invention relates to a topological structure of a ten-switch clamp type three-phase non-isolated photovoltaic inverter, belonging to the technical field of power electronic DC-AC conversion. Background technique [0002] Photovoltaic inverters require high conversion efficiency, low cost, and can withstand the adverse effects of large output voltage fluctuations of photovoltaic cells, and their AC output must also meet high power quality. Photovoltaic inverters can be divided into isolated type and non-isolated type according to whether they have an isolation transformer. The isolated photovoltaic inverter realizes the electrical isolation of the power grid and the battery panel, and ensures the safety of people and equipment, but it is bulky, expensive, and the system conversion efficiency is low. The structure of the non-isolated photovoltaic inverter does not contain a transformer, so it has the advantages of high efficiency, low cost, and smal...

AI Technical Summary

Problems solved by technology

The existence of leakage current will increase the harmonic content of inverter output current and increase electromagnetic interference, thereby reducing power quality, causing grid distortion, and causing unnecessary power loss, etc.

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