Dynamic air gap measuring device for use with rotating electrical machinery

摘要

The air gap between a rotor and a stator in rotating electrical machinery is determined using sonar techniques. An ultrasonic signal transmitter and receiver are mounted on one of the rotor and stator for transmitting ultrasonic signals to the other of the rotor and stator and receiving reflections therefrom. The time between signal transmission and reflected signal reception is determined, and the spacing of the rotor and stator is determined from the time, the velocity of sound, and the speed of rotation of the rotor.