Analysis and Experimental Study on Uncertain Fault of Active Magnetic Bearing Displacement Sensor

Active magnetic bearing (AMB) has been gradually applied to high speed rotating equipment to suspend rotor as it has many advantages, but some uncertain faults always appeal in the process of application. Meanwhile, displacement sensor is a key equipment of AMB control system, but when it is used in high speed atomizer, some uncertain problems are happened, such as expected range cannot be adjusted, and data characteristics cannot match well in the X-Y direction. In view of these problems, we gather electrical parameters in different frequencies, and establish the corresponding equivalent circuit models, to analyze the reasons of uncertain faults. Then we propose the high frequency electrical parameters characteristic analysis method to realize reliable judgment and reveal the essence of uncertain faults. Finally, comparative experiments are carried to verify the analysis methods, the results show that the electrical parameters of fault characteristic analysis method established for uncertain faults of displacement sensor has good theoretical and practical value.