Learning Observer Based Sensor Fault-Tolerant Control of Distributed Grid-Connected Inverter

Abstract

In order to improve the operating performance and reliability of the distributed grid-connected inverter, for the robust control of the system with sensor faults and uncertain disturbances, a fault-tolerant control strategy is proposed Firstly, the strategy adopts the output feedback control theory and the linear matrix inequality LMI algorithm, so it can design the inverter PQ power tracking closed-loop feedback control law. Secondly, considering the current sensor fault, it analyzes and derives the augmented fault model of the control system. By constructing a fault-tolerant control structure, which is based on the fault output signal conversion filter and PD-type learning observer, the online reconstruction and realtime compensation of fault signals are realized. Further, the system integration of output feedback control and fault-tolerant control is completed. Finally, using multi-fault scenario simulation, it verifies that the proposed control strategy achieves good effect of PQ power tracking control, and the sensor fault tolerance is strong.