Modeling and control of Dual Active Bridge by Fractional order controllers

Abstract

Modeling of a DC-DC converters is usually carried via small-signal approximations with small disturbances taken in account at steady state. Although due to presence of harmonic content or DC offset, the latter's modeling is restricted to certain range of operation. However, this is limited to a certain range of operation. This paper is a work based on modeling of Dual Active Bridge (DAB) type converters using Generalized Average Modeling. This type of procedure takes into account the harmonic as well as DC effect of the alternating current. After modeling the DAB, it's open loop transfer function is derived. Thereafter for controlling, parameters of fractional order (FO) controllers namely Fractional order PID and Tilt Integral Derivative (TID) are synthesized using heuristic optimization technique also known as Genetic Algorithm. The use of FO controllers enables more controllability of the plant than classical integer order controllers. The paper then compares the result obtained after simulation of plant controlled by FOPID and TID controllers respectively. It discusses various Power as well as Control results and then concludes the topic by summarizing the procedure and highlighting the importance of FO controllers.