A Method of Torsional Vibration Measurement Based on Electromagnetic Induction
基于电磁感应的扭转振动测量方法

This paper presents a new method of rotor torsional vibration measurement based on electromagnetic induction effect. The train of thought of this method is the relative movement between coil and permanent magnet. When coil cuts magnetic induction lines, the electromotive force is generated, and the voltage is proportional to relative velocity. Based on above principle, the change of instantaneous velocity can be calculated by corresponding voltage change at both ends of the coil, thus the torsional vibration is obtained by integral. The semi-cycle interpolation and comparison of the voltage at corresponding points with that of standard signal, accuracy of instantaneous velocity is highly ensured. In device designing, the effects of axis vibration and part of transverse vibration are eliminated at a certain extent through an appropriate measuring layout. Test verification shows that torsional vibration acquired by this method is consistent with the input loads, and this method has features of good accuracy, simple installation, user-friendly operation.