일반 절대위치 인코더를 이용한 회전진동 측정에 관한 연구

Abstract

A convenient process to measure the rotational vibration of a shaft in a mechanical or electrical rotating system using an ordinary absolute encoder is introduced. The output voltage signal from the encoder is sampled at an appropriate rate with a data recorder. The variation in angular position of the shaft at each time step is calculated based on the output voltage of the encoder. The angular speed of the shaft for a specific time step is then calculated by dividing the angular displacement by the corresponding time interval. The frequency components of the rotational vibration are calculated from the frequency analysis of the series of angular speeds. The validity of this process is examined via computer simulations and simple experiments, showing relatively good correspondence. The proposed method exploits the simple and convenient rotational speed measurement system using an absolute encoder and data recorder. The test results confirm that the proposed method can effectively measure the rotational vibration of a rotating machine with reasonable accuracy.