A Common Ground Series–Parallel Switched-Inductors Bidirectional DC–DC Converter With Wide Voltage Gain and Zero Input Current Ripple
Chao Zhang, Jiangmin Gu, Xiaoyong Zhu, Lei Xu, Yi Du, Zheng Hong
Abstract
This article presents a novel wide voltage gain bidirectional dc–dc converter (BDC) applied in film capacitor hybrid energy systems, which can effectively improve electric vehicles' (EVs) braking energy utilization rate. The proposed converter consists of an active switched-inductor cell, a quasi-Z-source cell, and a zero input current ripple cell. The switched-inductor cell has a wide range of voltage gain without an extreme duty cycle, increasing the power density and the reliability of the proposed converter. The switched-inductor cell can be controlled to series or parallel mode to alter the energy transfer path, effectively suppressing the current ripple and further reducing the converter power loss. In addition, the voltage stress on all but one of the power switches in this converter is less than the dc-link voltage, which increases the converter's power density and reduces system costs. The working principle of the proposed converter is analyzed, characterized, and parameterized. The effectiveness of the converter is experimentally verified by a 200 W prototype.