A Redundant-Sensor-Based Fault Reasoning Technique for Multi-Sensors

Abstract

In magnetic bearing systems or other relative devices with multi-sensors which states are not easy to be monitored and tested, multi-valued logic algebra based on sequential variables is suggested to be utilized in the fault diagnosis of the multi-sensors. The states of sensors and devices are both discretized to be three logic values: normal, abnormal and a transition state between them. On the basis of proving several relative theorems that can reveal the relation between the states of the sensors and that of the devices, the experiment arrangement is discussed in detail when the state of a device is anyone of the three states respectively. All the completed experiments should be necessary and be without redundant ones. A novel redundant-sensor-based fault reasoning technique is presented to be used for fault diagnosis of multi-sensors according to the experiment results. The reasoning result shows that it is not in all the occasions that the state of every sensor can be determined. Fault diagnosis should be carried out early when there are not too many sensors with fault.