Optimal Minimized Reactive Power Boundary Control Based on the Six Natural Switching Surface

This paper presents an optimal control method for dual active bridge (DAB) converter that can reduce reactive power and achieve fast dynamic response simultaneously by using the natural switching surface (NSS). Based on the built small signal model of DAB converter, the mathematical model of NSS is derived. The proposed control can adjust the switching sequence based on NSS for ensuring fast transient response during period of start-up, load change and reference variation. Combining of NSS switching sequence control and minimized reactive power algorithm with unified (a) harmonic analysis together, the dynamic state and steady state of DAB converter can be improved by employing proposed minimized reactive power boundary control (MBC). Both simulation and experimental results are provided to validate the advantages of proposed optimal control.