This paper investigates the simultaneous state and fault estimation problem for switched circuit systems subject to actuator faults, sensor faults, and external disturbances under an average dwell-time (ADT) switching law. First, a switched circuit model is established to describe the mode-dependent dynamics and the effects of different faults. Then, by incorporating the sensor-fault-related term into an augmented descriptor system, a multimode adaptive observer is developed to estimate the system states and unknown actuator and sensor faults. Furthermore, based on a mode-dependent Lyapunov function and the ADT switching technique, sufficient conditions are derived to guarantee the uniform ultimate boundedness of the estimation errors. Finally, numerical simulations and validation on a practical switched circuit platform are conducted to evaluate the state-estimation and fault-reconstruction performance of the developed observer. Simulation and experimental findings indicate the designed observer is capable of accurately tracking the system states and faults under switching operations and external disturbances.
- Open Access
- Article
Adaptive Observer-Based Fault Estimation for Switched Circuit Systems with Actuator and Sensor Faults
- Xince Kang,
- Yongjie Tan,
- Liheng Chen *
Author Information
Received: 29 Jun 2026 | Revised: 30 Aug 2026 | Accepted: 01 Sep 2026 | Published: 14 Sep 2026
Abstract
Keywords
switched circuit systems | fault estimation | adaptive observer | actuator fault | sensor fault | average dwell time (ADT)
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