Inductive Level Measurement Sensor with Magnetic Fluid

Magnetic fluid is usually used as a variably inductive core in inclination measurement sensor because it is provided with both liquidity and magnetism. This paper presents an inductive sensor based on magnetic fluid, detecting level and small inclination angles against horizontal plane. The working principle is introduced firstly, and then the theoretical analysis for principle of detection is deduced. Furthermore, the influencing factors are extracted from the principle function and are testified by experiment results. Finally, one kind of structures is designed to set up experiment. The experimental results showed that the sensor provides a signal proportionally with the inclination angle, which fit well with theoretical conclusion. The sensor sensitivity is proportional with magnetic susceptibility, with pumping frequency, and with the peak value of driving current.