Novel nonlinear control of Dual Active Bridge using simplified converter model

This paper addresses the control of a Dual Active Bridge (DAB) dc/dc converter. Closed-loop control of the output voltage is achieved by a novel nonlinear technique that separates the control algorithm into a linearization stage and a linear control law. The resulting DAB is capable of bidirectional power flow, and the transformer isolation makes it suitable for a wide variety of applications. The size of the isolation transformer is greatly reduced due to high-frequency (HF) operation resulting in high power densities. Also, switching losses are reduced since zero-voltage switching (ZVS) takes place over a range of operating conditions. Simulation and experimental results are presented for a 400 V-400 V, 10-kHz, and 10kW prototype.