Aiming at the single freedom active magnetic bearing(AMB) equipped with differential displacement sensors, the frequency domain characteristics of the controller outputs and the differential outputs of sensors were analyzed herein. The results show that: when different sensors go wrong, the phase difference among the different outputs of sensors and the controller outputs has a 180° difference. According to the feature a sensor fault diagnosis method was put forward. Simulation experiment of the method was presented, experimental research was done using an AMB test rig, the results show that the faulted sensor can be detected when the rotor is rotating in 18 000r/min. 

针对采用差动位移传感器的单自由度主动磁悬浮轴承，分析了不同传感器发生故障时控制器输出信号和传感器差值信号的频域特征，分析结果表明：当不同传感器发生故障时，传感器差值信号和控制器输出信号在故障频率点的相位差为180°，根据该特征可以识别发生故障的传感器。采用该方法在试验台上进行了试验研究，研究结果表明：当转子以18 000r/min旋转时，该方法可以检测到传感器的故障并识别出故障传感器。