A bridgeless double-liter soft-switching rectifier with the lowest loss in the auxiliary circuit

Abstract

The invention belongs to the technical field of power electronic conversion, and specifically relates to a bridgeless double-up soft-switching rectifier with the lowest loss in the auxiliary circuit, including a main circuit and an auxiliary circuit. The main circuit includes a first main switching tube and a first main rectifying diode , the drain of the first main switching tube and the anode of the first main rectifying diode are connected to point P to form the left bridge arm of the main circuit; the drain of the second main switching tube is connected to the anode of the second main rectifying diode The anodes are all connected to the Q point to form the right bridge arm of the main circuit; the source of the first main switching tube and the source of the second main switching tube are connected to the negative pole of the DC bus, and the first main rectifier diode Both the cathode and the cathode of the second main rectifier diode are connected to the anode of the DC bus. The invention realizes the zero-voltage turn-on of the main loop switch and the auxiliary loop switch, and the design of the absorbing capacitor reduces the turn-off loss and greatly improves the efficiency of the rectifier. The invention is used for rectification.

Description

technical field [0001] The invention belongs to the technical field of power electronic conversion, and in particular relates to a bridgeless double-up soft-switching rectifier with the lowest loss in an auxiliary circuit. Background technique [0002] Among many PFC circuits, Boost converters are widely used because of their simple structure, continuous input current and strong uniformity of characteristics. Among them, the bridgeless Boost PFC reduces the conduction loss by reducing the number of semiconductor devices on the working circuit, so as to improve the efficiency. However, the problem of switching loss in bridgeless PFC is prominent. When the switching frequency is increased, the switching loss in the circuit will increase accordingly, especially when the circuit works in CCM, the reverse recovery current of the freewheeling diode will increase the switching Turn-on loss of the tube. In order to reduce switching loss and dynamic switching stress, and achieve hi...

AI Technical Summary

Problems solved by technology

However, there are three types of problems in the ZVT-2CI inverter series: 1) When the switch ZCS of the auxiliary circuit is turned on, only IGBT devices with small EOSS (equivalent output capacitor energy storage) can be used, and the conduction loss and EMI cannot be ignored; 2) The unidirectional reset of the excitation current leads to the large volume of the transformer magnetic core selected, and two sets of auxiliary circuits are required to realize the auxiliary commutation work of the main switch under the bidirectional current output; 3) The auxiliary commutation diode has no clamping measures, and the overcharge vibration Bells cause high voltage stress and EMI

4) In high-frequency applications, under the small duty cycle of the main circuit, the commutation preparation time is insufficient

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