Optimal fault signal estimation

We consider here both fault identification and fault signal estimation. Regarding fault identification, we seek either exact or almost fault identification. On the other hand, regarding fault signal estimation, we seek either ℋ︁ 2 optimal, ℋ︁ 2 suboptimal or ℋ︁ ∞ suboptimal estimation. By appropriate combination of these two aspects, we formulate five different fault identification and fault signal estimation problems. We analyse and synthesize appropriate residual generators for fault identification and estimators which generate fault signal estimates for all these problems. Solvability conditions for all these problems are given. Also, for each of these problems, the architecture of integrating the residual generator that isolates the fault and estimators that estimate the fault signals is developed.