A method on fault detection and isolation of the actuator mechanism

作者：Jun Jie Huang; Zhen Jiang^*

来源：Journal of Applied Sciences, 2013, 13(7): 1100-1105.

DOI：10.3923/jas.2013.1100.1105

• Fault detection and isolation
• Incipient faults
• Initial state
• Input type
• Mechanism faults
• Sliding mode observers
• Slow variation fault
• Unknown disturbance

The actuator mechanism which is the bridge between the controller and the component, plays an important role in the nonlinear control system. The actuator mechanism fault has much effect on the whole nonlinear system performance. So the Fault Detection and Isolation (FDI) of the actuator mechanism has been researched. But the actuator mechanism fault is always considered as the input type fault in the control system. Some unknown disturbances and uncertainties exist in the system input for the nonlinear system. It makes the designed observer insensitive to the initial state of slow variation fault for actuator mechanism. So, it is difficult to diagnose the incipient fault of the actuator mechanism. A method of the FDI for the actuator mechanism is proposed. The actuator mechanism which is often made up of more than one actuator, is analyzed as the dependent dynamic system and its fault is an output type fault. A batch of sliding mode observers is designed for each actuator of the actuator mechanism. The residuals of the designed observers tend to zero in the actuators fault-free condition. Once the faults exist in the actuators of the actuator mechanism, the residuals of the observers immediately varied. So, the number of the fault actuators can be diagnosed and the fault actuators are isolated. The results show that the proposed method is very effective for the FDI of the actuator mechanism, especially for the incipient state of gradual variation fault.

• 出版日期2013
• 单位上海大学