Decentralized Control Strategy for Switching Harmonic Elimination of Modularized Input Parallel Output Series Dual Active Bridge Converter

Input parallel output series modular dc converters are widely used in high-gain applications, and interleaving multiple converters can reduce switching ripple. Yet, almost all existing interleaved control methods are centralized or require high-speed communication, and modularity is not truly achieved. For addressing this problem, a high-frequency switching harmonic elimination method is proposed without communication and centralized controllers. In the proposed method, voltage harmonic information on the parallel input side is sampled for the closed-loop regulation of the current harmonic phase, and the harmonic minimization of the specific frequency is thereby achieved. Compared with the traditional high-frequency harmonic elimination method (centralized interleaved parallel connection), the proposed method can achieve plug-and-play without communication and is insensitive to the electrical parameters of the modules. The experimental platform with three dual active bridge modules is built to verify the feasibility of the proposed method.