SU1199917A1 - Ferrosonde transducer of hole inclination angle - Google Patents

Abstract

A ferrozond converter of the angle of the well of the well, comprising a housing and an outer and inner frame installed in it, a ferrosonde located on the inner frame, two mutually perpendicular inductors, which are used to improve the accuracy and stability of the inductors. measuring the angle of inclination, the inductors are rigidly fixed in the housing, and their magnetic axes are at an angle of 45 relative to the sensitivity axis of the fluxgate. (L; o: o

Description

The invention relates to field geophysics and can be used in control systems for wiring directional wells.

The purpose of the invention is to improve the accuracy and stability of measuring the angle of inclination of a well.

The drawing shows a block diagram of the flux-gate transducer of the angle of inclination of the well.

The device comprises an outer 1 and an inner 2 frame constituting a gimbal. On the inner frame 2 perpendicular to its vertical axis of rotation there is a reinforced ferrosonde 3 and a tandem 4. Outside the frames in the inclinometer case there are two mutually perpendicular inductance coils 5 and 6, and their magnetic axes are at an angle of 45 relative to the axis of the ferrosound 3, The exciter winding of the fluxgate 3 is connected to the output of the excitation generator 7, the flux winding of the fluxgate 3 is connected to the input of: a filter 8, the output of which is connected to the first input of the first phase detector 9, the second input of which Inen with the second output of the generator 7 excitation, and the output of the first phase detector 9 is connected to the input of the first integrator 10, which in turn through the separation capacitor 11 is connected to the first input of the second phase detector 12, the output of which is connected to the input of the second integrator 13, output which is connected to the input of the device 14 registration, the first output of the generator 15 is connected to the second input of the second phase detector 12, and the second output of the generator 15 is connected to the input of the switch 16, two outputs of which are connected Yen respectively to the coils 5 and 6 inductance.

The principle of operation of the converter is as follows.

In an inclined borehole, under the action of a tiller 4, the outer frame 3 rotates and sets the axis of rotation of the inner frame 2 perpendicular to the plane of inclination of the borehole. At the same time, the plane of the inner frame 3, on which the ferrosonde is fixed due to the shifted center of gravity retains the horizontal position, the additional inductance coils 5 and 6 fixed rigidly with the inclinometer body change their position relative to the sensitivity axis of the fluxgate in proportion to the inclination angle of the inclinometer. Through the switch 16, the low-frequency current is fed from the output of the generator 15 alternately into additional coils 5 and 6 of inductance, in which an alternating magnetic field is created, the projection of which vector onto the sensitivity axis of the fluxgate 3 is proportional to the sine of the inclinometer, depending on what the coil 5 or 6 inductance is currently connected. In this case, taking into account the initial displacement of the magnetic axes of the coils 5

and 6 inductance relative to the axis of sensitivity of the fluxgate 3 at an angle of 45 is the relation:

AND

.

1i

0

 - C05

where b is the inclination angle of the inclinometer; Hgjn - projection of the magnetic vector of the inductor coil 5 on the axis of sensitivity of the fluxgate 3J

Co9 projection of the magnetic vector of the inductance coil 6 from the sensitivity axis of the fluxgate 3.

The initial offset 45 can be compensated for in the device 14 of registration.

An excitation generator 7 feeds a cavity 3. The second harmonic is extracted by a band-pass detector 8. The detection is carried out by a phase detector 9. The pulse voltage modulated by the frequency of the generator 15 is smoothed by the integrator 10. The time constant of the latter is chosen such

that the smoothing of the high-frequency voltage of the second harmonic occurs, but at the same time the low-frequency voltage is not suppressed with the frequency of the generator 15. The isolating capacitor allows the low-frequency modulation voltage to be separated from the direct voltage of the first 31 integrator 10, the value which is proportional to the azimuth. To unambiguously determine the angle of inclination of the well, the device uses a second phase detector 12, clocked by a low-frequency voltage taken from the generator 15, as well as a second integrator 13. The proposed technical solution has, compared to the well-known increase in the accuracy of measuring the angle of inclination of the well and increased stability, since stability of 199917. Katz / NIS inductance, as well as their identity is much higher than the stability of the additional ferrosonde and its identity with the main ferrosonde. In addition, in the proposed technical solution, a flux probe measures not the absolute value of the field created by the inductors, but their relative value. In this case, the multiplicative error of the conversion path from the fluxgate to the output of the second integrator is eliminated.

Claims (1)

FERROZOND PROBE CONVERTER of the Tilt Angle of the well, comprising a housing and an external and internal frame installed therein, a flux probe placed on the internal frame, two mutually perpendicular inductors, which are made in order to increase the accuracy and stability of the angle measurement tilt, the inductor is rigidly fixed in the housing, and their magnetic axis is located at an angle of 45 relative to the sensitivity axis of the flux gate. h U 8 -> 9 10 ¹¹ -Vr -> 12 thirteen /4