fault tolerant controller

This paper aims to present a novel and comprehensive model for actuator faults to address the problem of robust fault-tolerant controller design for networked control systems (NCSs) in the presence of phenomena such as random delays, model uncertainties, and actuator faults. For this purpose, firstly, the NCS has been appropriately modeled as discrete-time Markovian jump systems (MJSs) with partly-unknown transition probabilities. Then, the problem of mode-dependent static output feedback controller design has been studied not only as a convex optimization problem but also in the form of linear matrix inequalities (LMIs). Notably, the designed controller guaranteesthe stochastic stability of the closed-loop system in the presence of actuator faults and uncertainties. Finally, through numerical simulations, the theoretical results of this study are proved, and it has been shown that this method is more efficient and superior than other methods.

In this paper, a novel scheme for the design of the actuator fault-tolerant controller based on the fault identification in the linear systems has been presented. Fault identification has been proposed for the fault detection, determination of the faulty actuator (fault isolation) and estimation of the fault uncertain dynamics. For fault detection, a diagnostic observer has been designed for monitoring the condition of the system at every instance and generating the residual signal. After detecting the fault, the fault isolation module composed of a bank of observers has been activated to determine the faulty actuator. After determining the faulty actuator, estimation of the fault uncertain dynamics has been achieved by solving a linear matrix inequality. Then, a fault-tolerant controller has been proposed using the output of the fault identification module. The proposed scheme ensures the boundedness of the signals of the closed-loop system in the presence of the fault and satisfies the tracking objective. Simulation and comparison results were presented for verifying the effectiveness and performance of the proposed approach.

The fault tolerant controller (FTC) issue is one of the most important subjects in the system theory and control engineering which has many practical and industrial applications. In This paper, a new FTC has been designed in order to detect and compensate the sensors faults of permanent magnet synchronous motor (PMSM). To achieve this goal, sliding mode controller (SMC) and PMSM vector control have been used. In the faulty conditions, in order to achieve control purposes, two sliding mode observers (SMO) estimate the speed and currents of motor. The observers create virtual sensors for the feedback control. If sensors face with a condition that cause any fault, the FTC detects the fault and the virtual sensors are immediately used for sensorless control of motor. The stability of the closed-loop system has been investigated by the Lyapunov stability theory. Simulation results confirm good performance of the proposed FTC for PMSM.