Abstract:

A compensation method to improve the dynamic range of the high-temperature superconducting quantum interference device(HTS SQUID) magnetometer was proposed to deal with the problem of its narrow dynamic range and the locking difficulty without shielding. With the concept of shift compensation, a compensating magnetic field was formed around the probe of the magnetometer by a compensation coil to counteract most of the magnetic field to be measured, keeping the remained magnetic field within the dynamic range of the magnetometer, and the measured magnetic field was obtained by operational process of the counteracted magnetic field value and the value measured by the magnetometer. The experimental results indicate that the proposed method can improve the dynamic range of the magnetometer significantly without the penalty of sensitivity reduction. Its normal was realized even at the environment of serious interference and greatly changing magnetic field, meeting the demands of the geophysical magnet prospecting.

Key words: technology of instrument and meter, hightemperature superconducting quantum interference device(HTS SQUID) magnetometer, dynamic range, compensation coil, shift compensation, sensitivity