Three-port flyback photovoltaic grid-connected micro-inverter with power decoupling circuit, and modulation method

Abstract

The invention discloses a three-port flyback photovoltaic grid-connected micro-inverter with a power decoupling circuit, and a modulation method. The three-port flyback photovoltaic grid-connected micro-inverter comprises a three-port flyback conversion circuit, a full-bridge inverter circuit and an output filtering circuit, wherein a set of primary windings of the three-port flyback conversion circuit is connected with the novel power decoupling circuit to form a third port for realizing power decoupling, thereby effectively suppressing low frequency fluctuations on a DC bus and reducing thecapacitance of a decoupling capacitor, therefore, a thin film capacitor with long life and low capacitance is used instead of an electrolytic capacitor in the prior art. The three-port flyback photovoltaic grid-connected micro-inverter has the advantages of ensuring the life and reliability of the inverter, facilitating the realization of maximum power point tracking (MPPT), and improving the conversion efficiency of the inverter; meanwhile, the proposed decoupling circuit has simple structure, and only uses a switching tube and a capacitor, thereby reducing the cost and size of the inverter.

Description

technical field [0001] The invention relates to a photovoltaic grid-connected micro-inverter, in particular to a three-port flyback photovoltaic grid-connected micro-inverter capable of realizing the power decoupling function. Background technique [0002] As a world-recognized clean energy, solar energy has many advantages such as wide distribution, renewable, and no pollution to the environment. At the same time, the development and utilization of solar energy has solved the problems of environmental pollution and energy shortage faced by human beings, and has become the most promising energy source for development at present and in the future. One of the new energy sources. [0003] In recent years, photovoltaic power generation systems have been widely used in the rapid growth and high demand of electricity, and more and more small factories and residential users have applied photovoltaic power generation systems to small-scale power generation. Micro-inverters are curr...

AI Technical Summary

Problems solved by technology

However, most of the power decoupling circuits currently proposed have complex structures and many components, which are not compatible with the low cost and small size of micro-inverters.

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