Eddy current transducers are widely used because of its untouchable detecting

fast dynamic response and better adaptability

but it has great temperature drift.The principle of the eddy current transducers are discussed

and the mainly reasons resulted in the temperature drift are analyzed.Mathematical model detecting coil is given

accuracy of model is proved by test in thermostat;the demodulation-circuit parameter temperature drift is counteracted

the stability of the output gap signal is improved.Proved the compensation circuit of detecting coil and demodulation by test

curve of the temperature and voltage of detecting coil output is achived.Contrasting the curves with and without compensation

result is satisfied of the national standard JJG 644-90

the temperature drift less than 12.1 %

the compensation is effective.