Fault detection filter design and optimization for networked control systems

The problem of robust fault detection filter design and optimization was studied for networked control systems (NCS) with unknown time-varying delay. Considering the impact of the unknown time-varying delay on the NCS, the fault detection model of NCS was established. Based on the model, the robust fault detection filter was developed. The existence condition and solutions of the filter were derived by using linear matrix inequality techniques. Furthermore, to improve the performance of the robust fault detection filter, a time domain optimization approach was proposed. The optimum solution to the optimization problem was given in the form of Moore-Penrose inverse of matrix. A numerical example is provided to show that the proposed method has good performance on small fault detection capability and fault detection speed.