Abstract: In order to meet the ultra-high-speed turbine speed measurement requirements (high temperature, high speed, strong vibration, shock)of the servo gas source under harsh environmental conditions, designed the high temperature miniaturization and ultrahigh speed rotational speed sensor. The speed sensor is designed according to the principle of electromagnetic induction, taking an open magnetic circuit structure which solves the high-temperature, highspeed problems in the face of measurement. This new senor has the characteristics of small size, standing high temperature and high precision.

Key words: Speed sensor, Electromagnetic induction, Servo sgstem