A Quasi-Parallel Resonant Switched Capacitor DC–DC Converter With Wide Input Voltage Range Regulation and Enhanced Dynamic Performances

The wide-range and high-efficiency dc–dc converters are in high demand for various applications, such as distributed systems, electric vehicles, and dc buildings. Resonant switched capacitor converters (ReSCCs) can achieve soft switching, have small passive device capacity, and exhibit low-voltage stress, but the voltage ratio is difficult to be regulated continuously. In this article, a quasi-parallel resonant switched capacitor dc–dc converter is proposed to satisfy the design requirements, which incorporates an ReSCC with soft-switching and variable voltage ratio, as well as a buck converter. In addition, a simplified optimal trajectory controller for ReSCC is investigated, which can be combined with proportional-integral (PI) controller of buck converter to enhance the load transient of the proposed converter. Moreover, the input voltage feedforward control is implemented with the optimized feedforward coefficient to suppress the input voltage disturbance. The proposed converter can achieve high efficiency and rapid dynamic response over a wide conversion range. The correctness of the theoretical analyses is verified by a 36–60 V–5-V/20-A prototype.