High-gain active lossless clamping interleaving converter with internal transformer and voltage-multiplying structure

Abstract

The invention discloses a high-gain active lossless clamping interleaving converter with an internal transformer and a voltage-multiplying structure. The high-gain active lossless clamping interleaving converter comprises two input inductors, two power switching tubes, two clamping switching tubes, two voltage-multiplying diodes, two output diodes, two clamping capacitors, two voltage-multiplying capacitors, two output capacitors and one internal transformer with three windings. According to the invention, a voltage gain of the converter is expanded and voltage stresses of the power switching tubes and the diodes are reduced by the internal transformer; the leakage inductance of the internal transformer is utilized to implement zero voltage switching of the switching tubes and inhibit reverse recovery currents of the diodes; a clamping circuit consisting of the clamping switching tubes and the clamping capacitors effectively adsorbs a voltage spike when the power switching tubes are switched on and switched off and implements lossless transfer of energy; the voltage-multiplying circuit structure is utilized to further improve the gain of the converter and further reduce the voltage stresses of the power switching tubes and the diodes; the high-gain active lossless clamping interleaving converter has a simple circuit structure, is convenient to control and is suitable for the high-gain and high-efficiency grid-connected photovoltaic power generation transformation place.

Description

technical field [0001] The invention relates to a DC-DC converter and its application, in particular to a high-gain active non-destructive clamp interleaved parallel converter with a built-in transformer and a voltage doubler structure. Background technique [0002] In the photovoltaic power generation system, since the output voltage of a single photovoltaic cell is low, and the voltage required for inverter grid-connected power generation is relatively high, a first-stage DC-DC converter is required to convert the low-voltage DC into a high voltage suitable for grid connection. Voltage DC. In the distributed photovoltaic power generation scheme, the power capacity of a single photovoltaic cell is small, but the requirements for efficiency are high. Therefore, how to realize a single-stage converter with high gain, high efficiency and simple structure is of great significance for promoting the development of the photovoltaic industry. [0003] The voltage gain of the conv...

AI Technical Summary

Problems solved by technology

[0003] The voltage gain of the conventional single-phase single-transistor boost DC-DC converter is only determined by the duty cycle, the voltage gain is limited, and it is difficult to meet the high-gain conversion requirements

The voltage stress of the power switch tube is relatively large, and it is difficult to use a low-voltage high-performance switch tube to reduce the conduction loss

Moreover, the converter works in a hard switching state, and the switching loss is relatively large

In order to realize the soft switching action of the Boost converter, in recent years, some soft switching schemes by adding active power switches or passive devices have been studied successively. Although these circuits realize the soft switching action, they cannot reduce the voltage stress of the switching tube. It is also impossible to realize the high-gain conversion of the system

In order to increase the voltage gain of the converter, a switch capacitor solution is usually used, but this solution requires a large number of switch tubes, which increases the system cost

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