TY - GEN
T1 - Circulating current reduced three level DC-DC converter with two transformers for battery chargers
AU - Guo, Zhiqiang
AU - Sun, Kai
AU - Sha, Deshang
N1 - Publisher Copyright:
© 2016 IEEE.
PY - 2016/7/13
Y1 - 2016/7/13
N2 - This paper introduces an improved isolated three-level (TL) DC-DC converter for battery charger. Conventional TL DC-DC converters usually have one transformer for isolation. Simultaneously, large circulating current freewheels at the primary of the transformer, which lowers the efficiency. A TL DC-DC converter with two transformers to reduce the circulating current is proposed in this paper for battery chargers. Like the conventional TL DC-DC converters, there is no addition switches at the primary of the transformers. The two transformers are connected in series. The flying capacitor of the converter is split into two, and the middle node of the flying capacitors are connected to the neutral point of the two transformers. The corresponding secondary windings of the transformers are also connected in series. Cooperating with four-diode rectifier stage, the primary circulating current can be reduced. The ZVS of the lagging switches is determined by the energy stored in a magnetizing inductor rather than leakage inductance. Because of the ZVS and reduced circulating current, the efficiency of the proposed converter is better than the conventional one. In the end, the performance of the proposed converter is verified by a 1kW prototype.
AB - This paper introduces an improved isolated three-level (TL) DC-DC converter for battery charger. Conventional TL DC-DC converters usually have one transformer for isolation. Simultaneously, large circulating current freewheels at the primary of the transformer, which lowers the efficiency. A TL DC-DC converter with two transformers to reduce the circulating current is proposed in this paper for battery chargers. Like the conventional TL DC-DC converters, there is no addition switches at the primary of the transformers. The two transformers are connected in series. The flying capacitor of the converter is split into two, and the middle node of the flying capacitors are connected to the neutral point of the two transformers. The corresponding secondary windings of the transformers are also connected in series. Cooperating with four-diode rectifier stage, the primary circulating current can be reduced. The ZVS of the lagging switches is determined by the energy stored in a magnetizing inductor rather than leakage inductance. Because of the ZVS and reduced circulating current, the efficiency of the proposed converter is better than the conventional one. In the end, the performance of the proposed converter is verified by a 1kW prototype.
KW - DC-DC
KW - ZVS
KW - reduced circulating current
KW - three-level
UR - http://www.scopus.com/inward/record.url?scp=84983329135&partnerID=8YFLogxK
U2 - 10.1109/IPEMC.2016.7512265
DO - 10.1109/IPEMC.2016.7512265
M3 - Conference contribution
AN - SCOPUS:84983329135
T3 - 2016 IEEE 8th International Power Electronics and Motion Control Conference, IPEMC-ECCE Asia 2016
SP - 78
EP - 84
BT - 2016 IEEE 8th International Power Electronics and Motion Control Conference, IPEMC-ECCE Asia 2016
PB - Institute of Electrical and Electronics Engineers Inc.
T2 - 8th IEEE International Power Electronics and Motion Control Conference, IPEMC-ECCE Asia 2016
Y2 - 22 May 2016 through 26 May 2016
ER -