Robust Fault-Tolerant Control of Four-Phase Interleaved DC-DC Converter Under Switch Fault for Fuel Cell Application

The multi-phase converter has been widely used for fuel cell (FC) applications. However, despite the continuous operation of the converter, the switch fault would deteriorate the control performance of the closed-loop controller, and cause increased input current ripple. To this end, in this paper, a robust fault-tolerant control based on the framework of active disturbance rejection control (ADRC) is proposed for a four-phase interleaved converter. In particular, the system control gain is updated based on the duty cycles, so that the control performance under switch fault can be maintained. On the other hand, the method of phase shift reconfiguration is proposed to suppress the input current ripple of multi-phase converters under switch fault, in which the optimal phase shift is calculated by optimizing the object function derived from the input current ripple model. The experimental results are provided to validate the effectiveness of the proposed method.