Fault Tolerant Control for Kori Unit 1 Steam Generator

In order to implement more reliable control systems, failures of a controller, a sensor and an actuator should be taken into consideration in the process of control system design. Traditionally there have been two approaches for dealing with fault-tolerant control problem: active redundancy and passive redundancy. Active redundancy has no reconfiguration part to take an action such as diagnosing and selecting intact controller when a controller failure occurs, that is, one controller guarantees the system stability and performance under failure of the other controller. Meanwhile, passive redundancy has reconfiguration parts which supervise the system, reject the faulty controller, and select the sound controller which performs the mission. Active redundancy structure for fault-tolerant control is focused in the paper and design methods of fault tolerant state feedback control and fault-tolerant output feedback control are proposed, which makes control a system reliable while guaranteeing stability and performance in the sense of H∞ norm, in the face of controller failures in the dual-controller configuration. The proposed method is applied to Kori Unit 1 steam generator level control system. The results show that the steam generator water level is well controlled in the situation of one controller failure