An Advanced Loop Shaping Control Methods for Performance Improvements in a High Frequency Switched SiC based Converters

The use of power electronic systems in critical applications like Battery charging, Distributed generation, Fuel cell power conditioners, Automotive SMPS systems, etc. demands higher efficiency, cost effective, high-power-density converters. As power increases, converter paralleling are preferred with novel topologies. A Poly-phase Buck Converter (PBC) with high frequency switching with Silicon Carbide (SiC) based systems meets the above requirements, with its features of minimum ripple current and voltage, low volume passive components and ease of control. Traditional PI/PID controller based voltage regulation is sluggish during the transient and dynamic changes in the load at this switching frequencies. This necessitates the requirement of an improved control with better loop stabilization for this high frequency operations. This paper presents Type compensator-based loop stabilization methods in which the poles and zeros of the compensator are shifted based on the required frequency response parameters. A new controller design approach called Parallel control is implemented with the help of Type compensators to achieve a better response than the conventional. Modeling of the PBC, the proposed control strategy, design and frequency response analysis of the control scheme, and necessary experimental results are presented in this paper.