Dual-mode Modulation of Bipolar Buck Converter with Voltage Balancing and Short-circuit Faulttolerant Operation Capability

In this paper, the dual mode operation is proposed for bipolar buck converter with integrated voltage balancing and short-circuit fault-tolerant capability. During normal operation, the converter can simultaneously achieve output voltage regulation and bipolar voltage balancing. The coupling relationship between the above two control aims and the potential instability are analyzed. In the event of a short-circuit fault, by adjusting the converter modulation, both fault isolation and voltage regulation can be realized. With consideration of both normal operation and fault-tolerant mode, the corresponding circuit and control designs are analyzed. The proposed dual-mode operation strategy is tested by simulation and experimental results, in verification of bipolar voltage balancing and fault reconfiguration capability.