DEVICE FOR GENERATION OF ELECTROMAGNETIC FIELD OF TOROIDAL COIL IN GEOLOGICAL ENVIRONMENT Russian patent published in 2016 - IPC G01V3/28 

FIELD: measuring equipment.

SUBSTANCE: invention relates to the field of geophysical research in oil wells, namely to a device for studying the electrical properties of the rock (reservoir) surrounding a borehole, the method of electromagnetic logging. Technical effect: The device comprises a base in the form of conductive nonmagnetic metal pipe and generating at least one toroidal coil structure, situated concentrically ground, and is provided with a sealed enclosure of a nonmagnetic metal which is electrically connected to the substrate. Near the generator on the same base near the toroidal coil a measuring toroidal coil is placed. Both coils are installed inside the housing with an insulating gap. Measuring toroidal coil comprises at least two windings, signal and compensating. Signal winding of the measuring coil is connected to the input of feedback converter-amplifier. Compensating winding of the measuring coil is connected to the output of feedback converter-amplifier. Between the generator and the measuring coils a electrostatic shield is located which is electrically connected to the base and the housing of the device.

EFFECT: increasing measurement accuracy while simplifying the construction.

5 cl, 3 dwg