Interval sliding mode observer-based fault accommodation for non-minimum phase LPV systems with online control allocation

Abstract

This paper proposes an interval sliding mode observer (ISMO)-based sliding mode actuator fault accommodation (FA) framework for non-minimum phase linear-parameter-varying (LPV) systems involving online control allocation (CA) problem. Firstly, a specifically designed coordinate transformation is introduced to deal with the non-minimum phase issue. Then, an ISMO is proposed to estimate the set of admissible values for the states of the faulty LPV systems, which combines the interval observer technique and the sliding mode observer technique. A fault-tolerant control (FTC) law with an online CA scheme is subsequently designed by stabilising the ISMO instead of the original faulty LPV system. Finally, a simulation for an inverter used in China Railway High-speed (CRH) is presented to illustrate the effectiveness of the proposed framework.