A novel non-isolated magnetically coupled based bidirectional quadratic converter

This paper introduces a new magnetically coupled four-switches non-isolated bidirectional quadratic converter with a damping network for wide voltage conversion ratio. Due to its broad voltage conversion range in both ways, it can be easily suitable for the applications like hybrid electric vehicles (HEV), battery charging, uninterruptible power supplies (UPS), etc. Conventional bidirectional converter when operated in boost mode of operation suffers from right half plane (RHP) zero problems. Also, conventional bidirectional converter cannot operate to extremely high duty cycle or petite duty cycle. In this paper, two conventional boost converters are cascaded and diodes are replaced by bidirectional switches. The topology utilizes magnetic coupling of two inductors and a damping network. With this arrangement, RHP zero for the quadratic boost mode of operation will be completely eliminated and capable of handling large ripple currents in quadratic buck mode of operations. This enables simple and linear control of proposed bidirectional quadratic converter. The steady state analysis and small signal modeling are carried out. Finally, a prototype circuit is implemented to verify the performance of the proposed bidirectional quadratic converter.