Comparison of Decoupling Control Strategies for Multiple Active Bridge DC-DC Converter

With the benefit of high power density and bidirectional multi-input multi-output (MIMO) power transfer capability, the multiport active bridge (MAB) topology has been widely used in the electric transportation onboard propulsion and charging systems. However, the nonlinear power transfer behavior brings challenge to its control system design. As the dynamic performance of the traditional proportional-integral (PI) controller is characterized by a relatively slow response and large overshoot. To address this issue, decoupling control strategies have been proposed to enhance the transient response and control flexibility of the system. This paper discussed and compared several nonlinear decoupling control methodologies including the small signal state-space linearization based and optimization algorithm based decoupling control. Simulation verifications are performed to conclude the suitable applications.