A Linear Observer Design for Fast Open Switch Fault Detection of Interleaved Boost Converters

This paper proposes a fault detection, identification, and reconfiguration approach for an open switch fault (OCF)for the interleaved DC-DC boost converter (IBC). The proposed technique is based on a state space observer nonlinear model with a linear design. The main idea is based on evaluating the residual vector created by comparing the real and the estimated inductor phase currents. The chosen observer model with the linear design and the adopted control system of the IBC will result in a very fast fault detection time using just the sensed variables of the circuit. Moreover, a thresholding strategy is adopted and tested under several conditions to avoid false diagnosis cases. The effectiveness of the proposed method for one or more open switch faults has been verified by simulation for three and five interleaved boost converters.