Title :
The Analysis of the Charge Unbalance in Flying Capacitors of a Novel Three-level ZVS Converter
Author :
Zhao, Chen ; Zhang, Junming ; Wu, Xinke ; Qian, Zhaoming
Author_Institution :
College of Electric Engineering, Zhejiang University, Hangzhou, China, powerland@zju.edu.cn
Abstract :
This paper analyzes the two different operation principles of an improved three-level ZVS converter, which employs a coupled inductor to achieve zero-voltage switching, under two different control strategies. It indicates that an inapposite choice of control strategy will cause the charge unbalance in flying capacitors and result in the failure of the three-level operation under light load and open voltage loop condition (this condition may occur in dynamic load). The reasons are analyzed in detail. With a modified control strategy the charge unbalance is removed, and a 1kW, 80kHz experimental proto type is made to verify the phenomena and the theoretical analysis.
Keywords :
ZVS; charge-unbalance; flying-capacitor; three-level; Bridge circuits; Capacitors; Diodes; Inductors; Leg; Open loop systems; Switches; Switching converters; Voltage control; Zero voltage switching; ZVS; charge-unbalance; flying-capacitor; three-level;
Conference_Titel :
Power Electronics and Drives Systems, 2005. PEDS 2005. International Conference on
Print_ISBN :
0-7803-9296-5
DOI :
10.1109/PEDS.2005.1619812