Sensor and Actuator Fault-Hiding Reconfigurable Control Design for a Four-Tank System Benchmark

Fault detection and compensation plays a key role to fulfill high demands for performance and security in today's technological systems. In this paper, a fault-hiding (i.e., tolerant) control scheme that detects and compensates for actuator and sensor faults in a four-tank system benchmark is introduced. Faults are modeled as a drastic gain loss in actuators (i.e., pumps) and in sensor measurements (i.e., level detection) which could lead to a large loss in the nominal performance. A configurable decentralized Proportional Integral (PI) controller is designed and applied to a Linear Time Invariant (LTI) system where virtual sensors and virtual actuators are used to correct faulty performance through the use of a pre-fault performance. Simulation results showed that the developed approach can handle different types of faults and able to completely and instantly recover the original system performance/functionality directly after the occurrence of faults.