An isolated photovoltaic grid-connected inverter with a double-branch structure and its working method

Abstract

The invention discloses an isolated-type photovoltaic grid-connected inverter with a dual-branch structure and a working method of the same. The inverter comprises a main circuit, a dual-core DSP main control circuit and an auxiliary switch power source circuit, wherein the main circuit comprises a preceding-stage boosting module, a full-bridge topology inverter circuit and an output filtration module which are connected in succession, the preceding-stage boosting module comprises two branches, and each branch comprises an input filtration module and a high-frequency isolated boosting circuit; and the dual-core DSP main control circuit comprises a first DSP controller and a second DSP controller, the first DSP controller is used to drive the high-frequency isolated boosting circuit and realize tracking and control of a point with the maximum output power on a preceding-stage dual-way solar cell panel, the second DSP controller is used for full-bridge inverter control and grid-connected current inverter control, and the first DSP controller and the second DSP controller are connected by a GPIO module. The isolated-type photovoltaic grid-connected inverter with the dual-branch structure and the working method of the same disclosed by the invention adopt dual DSPs, can realize time-divided independent control, and can increase a safety response speed of a system. Meanwhile, the preceding-stage boosting module comprises the two branches and has the advantages of high efficiency.

Description

technical field [0001] The invention relates to the research field of photovoltaic grid-connected inverters, in particular to an isolated photovoltaic grid-connected inverter with a double-branch structure and a working method thereof. Background technique [0002] Every transformation and development of human society is inseparable from the use of new energy. Energy plays an extremely important role in the development of science and technology and the improvement of people's living standards. Among traditional energy sources, coal and oil are used. Natural gas and other fossil energy are the main sources. Although the use of traditional energy has promoted industrial development, it has also caused a series of ecological environment deterioration. Fossil energy resources are limited and will eventually be exhausted under unreasonable use. Therefore, in order to meet the sustainable development of energy demand, the research on new energy has attracted great attention. ...

AI Technical Summary

Problems solved by technology

However, most of the currently researched photovoltaic inverters are used in power station photovoltaic grid-connected power generation systems, which are not suitable for large-scale promotion and are not flexible enough.

Even if there are photovoltaic inverters designed for household photovoltaic grid-connected power generation systems, there are many disadvantages such as large size and low efficiency.

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