Multi-resonant network unit isolated high-gain DC converter

Abstract

The invention discloses a multi-resonant network unit isolated high-gain DC converter comprising an input power supply Vg, a first switching tube S1, an active clamping circuit, a multi-winding transformer T, an output capacitor Co, an output diode Do and a load R. The multi-winding transformer T comprises a primary winding Tp and multiple secondary windings Tk, wherein k is a positive integer. The active clamping circuit comprises a first capacitor Cr, a second switching tube S2 and a resonant inductor Lr. The multi-resonant network unit isolated high-gain DC converter also comprises quasi voltage multiplying structures. The quasi voltage multiplying structures comprise quasi voltage multiplying capacitors Ck and quasi voltage multiplying diodes Dk. The switching logic of the first switching tube S1 and the second switching tube S2 is complementary connection. The multi-resonant network unit isolated high-gain DC converter has the advantages that the structure is simple, the number ofthe switching tubes is less, the voltage stress of the diodes can be reduced, zero current disconnection of the diodes can be realized and the turn ratio of the transformer can be reduced; zero voltage connection of the primary switching tube can be realized and the voltage stress can be reduced; and soft switching of the power tubes can be realized and the switching loss and the EMI interferencecan be reduced.

Description

technical field [0001] The invention relates to the technical fields of photovoltaic new energy, fuel cells, and uninterruptible power supplies, and in particular to an isolated high-gain DC converter with a multi-resonance network unit. Background technique [0002] At present, energy crisis and environmental issues are getting more and more attention. Governments of all countries are scrambling to devote themselves to green new energy. Among them, photovoltaic new energy is widely used all over the world due to its advantages of zero pollution, no noise, convenient equipment installation and huge potential. Taking the two-stage photovoltaic grid-connected power generation system as an example, due to the limited characteristics of photovoltaic cells, too many photovoltaic cells cannot be connected in series. The output voltage of a typical photovoltaic module is 33-50V, and the power is about 100W-300W. In order to increase the voltage to the conventional DC bus voltage ...

AI Technical Summary

Problems solved by technology

The high-gain converter with electrical isolation usually has a complex structure of the converter (the number of switching elements is large), the voltage stress of the switch tube and diode is large, or the soft switching of all power tubes is not fully realized.

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