Interleaved zero‐voltage switching three‐level converter with less output inductor counts

Abstract

An interleaved three-level converter with the new current doubler rectifier is proposed. The main advantages of the proposed converter are zero-voltage switching (ZVS) turn-on for all switches, low output ripple current and less voltage stress of the output diodes. Two three-level converters connected in parallel are used to decrease the input current ripple, as well as to reduce the current rating of power switches. At the secondary side, two current doubler rectifiers sharing the same output filter inductors to reduce the output current ripple. Compared with the conventional centre-tapped rectifier and current doubler rectifier, the adopted current doubler rectifier has less output current ripple. The output capacitance of the power switch and the leakage inductance (or external inductance) are resonant at the transition interval so that the power switches can be turned on under ZVS. The adopted converter can be employed in high voltage input and high current output applications. Experiments with a prototype with 750-800 V input and 48 V/30 A output are provided to verify the theory analysis.

Investigation of a Resonant dc–dc Converter for Light Rail Transportation Applications

“…Based on the voltage divider of the resonant tank by C r1 , L r1 , L m1 , and R ac1 , the voltage gain of the resonant circuit is calculated in (8).…”

“…Conventional full-bridge dc-dc circuits use the insulated gate bipolar transistors (IGBT) devices with 1200 V voltage rating for high input voltage applications. Three-level converters [7][8][9] based on high frequency Metal-Oxide-Semiconductor Field-Effect Transistor (MOSFET) power semiconductors were widely used in modern power converters to overcome low frequency problem of IGBT-based full-bridge converters. Soft switching dc-dc converters [10][11][12][13] have been studied and presented to realize high efficiency power circuits.…”

A Three-Leg-Based Full-Bridge Converter with Active Current Doubler Rectifier

“…In [8][9][10][11], hybrid dual-transformer structure based on current doubler rectifier(CDR) was presented for high output current occasions. The converter in [8][9] can reduce the current ripple in the output filter.…”

Analysis of a Series‑Parallel Resonant Converter for DC Microgrid Applications

“…Therefore, the circuit size cannot be reduced due to limited switching frequency. To overcome this problem, the circuit topologies with series-connected switches or converters [5][6][7][8][9][10][11][12] and multilevel converters [13][14][15][16][17][18][19][20] can adopt low voltage stress and high switching frequency operation power switches in high voltage input cases. Therefore, the voltage stress on active devices can be reduced in these circuit topologies.…”

“…Thus, the soft switching operation on power semiconductors can be realized over the whole load range. Compared to past three-level circuit topologies in [13,19,21], this circuit topology has simpler control and less circuit components for high voltage input applications. Experiments of a laboratory circuit with 750~800 V input voltage, 24 V output voltage and 40 A load current are demonstrated to confirm the benefits of the circuit.…”