SU1188690A1 - Arrangement for well lateral logging - Google Patents

Abstract

1. DEVICE FOR SIDE WAGES OF WELLS, including an alternator, a side logging probe, first and second remote electrodes, a first input potential transformer of the probe, a measuring potential transducer of the probe, an input current transformer of the probe, a measuring current transducer of the probe, a computing unit and a dividing system, the input of the side logging probe is connected to the output of the alternator, the first output of the side logging probe is connected to the input of the input current transformer of the zones a, the output of which is connected to the input of the probe current transducer, the second output of the lateral logging probe is connected to the first input of the first input potential transformer of the probe, the output of the probe current transducer is connected to the first input of the dividing system, in order to simplify the design and increase operational reliability, a second input potential transformer of the probe was additionally introduced, with the first input of the second input potential transformer of the probe connected to the second input of the first input potential transformer of the probe is connected to the first remote electrode, the first and second outputs of the first input potential transformer of the probe are connected respectively to the first and third inputs of the computing unit, and the first and The second outputs of the second input transformer - corresponding to the second and fourth inputs of the computing unit; the first and second outputs of the computing unit are connected to the first and to the the second inputs of the measuring potential transducer of the probe, and the output of the latter is connected to the second input of the dividing system. 2. The device according to claim 1, characterized in that the computing unit contains a voltage divider, a subtraction cell, and (L is a scale amplifier, the first input of the computing unit is the first input of the subtraction cell, the second input of the computing unit is the first input of the divider the third and fourth inputs of the computing unit are the second and third inputs of the voltage divider, respectively; the output voltage is connected to the second input of the subtraction cell, the output of which is connected to the input of the large-scale amplifier, and The outputs of the latter are the outputs of the computational block, in addition, the division factor k of the voltage divider is ijiji i, where / j, 1 rad-distances, respectively, from the first and second remote electrodes to the center of the lateral logging probe, and d-- L 1 3. The device according to claim 1, characterized in that the computing block is made in the form of the first and second input potential transformers of the probe, the first output of the first input potential transformer of the probe being connected to the first output of the second th potential transformer

Description

The second probe output is the first output of the computing unit, and the second output of the second input potential transformer of the probe, respectively, the second output of the computing unit.

wherein the first outputs of the first and second input transformers of the potential of the probe are the beginnings or the ends of their secondary windings, and the ratio of the transformation ratios of said transformers is k.

one

The invention relates to a field geophysical technique, namely, devices implementing a side logging method and intended to measure apparent electrical resistivity in oil, gas, hydrogeological wells drilled for the purpose of mining and exploration of mineral resources.

The purpose of the invention is to simplify the design and increase the operational reliability of the device;

FIG. 1 shows a block diagram of the proposed device; in fig. 2 - computing unit; in fig. 3 shows an embodiment of the computing unit based on the first and second input potential transformers of the probe.

FIG. 1 shows an alternating current generator 1, a side logging probe 2, the first 3 and second 4 remote electrodes, the first input potential transformer 5 of the probe, the measuring transducer of the potential of the probe, input current transformer 7 of the probe, the measuring current converter of the probe 8, computing unit 9, dividing system 10, the second input potential transformer probe 11.

The input of the side logging probe 2 is connected to the output of the alternating current generator 1, the first output of the side logging probe 2 is connected to the input of the input current transformer 7 of the probe, the output of which is connected to the input of the probe current measuring transducer 8, the second output of the side logging probe 2 is connected to the first input of the first input potential transformer probe 5, the output of the measuring transducer 8 current probe connected to the first input of the dividing system 10, the first input of the second input transformer 11 potential of the probe is connected with the second output of the probe 2 side logging, and the second input with the second remote electrode 4, the second input of the first input transformer 5 of the potential of the probe is connected to the first remote electrode 3, the first and second outputs of the first input transformer 5 of the potential of the probe are connected respectively to the first and third inputs computing unit 9, and the first and second outputs of the second input transformer 11, respectively, with the second and fourth inputs of the computing unit 9, the first and second outputs of the computing unit 9 are connected to p rvym and second inputs of the sensor probe 6 potential, and the output of the latter is connected to a second input of the separating system 10.

FIG. 2 shows the subtraction cells 12, the voltage divider 13 consisting

resistors 14 and 15, and a scale amplifier 16. The first input of the cleaning cell 12 is the first input of the computing unit 9, the first input of the voltage divider 13 is the second input of the computing unit 9, the second and third inputs of the voltage divider 13 are the third and fourth inputs of the computing unit 9. The output of the voltage divider 13 is connected to the second input of the subtraction cell 12, the output of which is connected to the input of the amplified amplifier 16, and the outputs of the latter are supplied by the outputs of the computing unit. FIG. 3 shows a computing unit made on the basis of the first and second input transformers 5 and 11 of the probe potential, with the first output

5 of the first input potential transformer of the probe is connected to the first output of the second input transformer 11 of the probe potential, the second output of the first input transformer of the potential 5 of the probe is the first output of the computing

0 block 9, and the second output of the second transformer 11, respectively, the second output of the computing unit. The first outputs of the first and second input transformers 5 and 1 1 are the beginnings of their secondary windings and are marked with dots.

The device works as follows.

The alternator 1, located on the surface, creates in the power supply circuit of the probe 2 of the side logging current with a frequency of 300-400 Hz, a value of 0.4-0.5 A 0, which generates an electric field in rocks. The electrical resistivity p of the medium, measured by a lateral logging probe, is determined by the expression

and.

to

3

U

where Uco - potential of the probe is relatively

infinitely distant point; 1h - the value of the probe current; Кз is the coefficient of the probe, depending on the design and geometrical dimensions of the lateral logging probe.

A signal proportional to the probe current I, through the input current transformer 7 of the probe, is fed to the input of the measuring current transducer 8 of the probe, in which it is converted into a form suitable for transmission to the surface and further processing in a dividing system 10 in accordance with the formula indicated.

The potential Uoo of the lateral-carriage probe 2 relative to an infinitely remote point is determined by the first 3 and second 4 remote electrodes, the first 5, second 11 input potential transformers of the probe and computing unit 9. A voltage acts between the first and second inputs of the first input transformer 5 of the probe potential equal to the potential of the UH probe relative to the first remote electrode 3. Accordingly, between the first and second inputs of the input transformer 1 1 there is a voltage equal to the potential Usz of the probe relate no second remote electrode 4.

Since electrodes 3 and 4 are located at a considerable distance from the center of the lateral-logging probe 2, probe 2 can be considered a point source of current.

The voltage from the output of the computing unit 9, proportional to the potential Uoo of the probe relative to the infinitely distant point, is fed to the input of the measuring transducer 6 of the potential of the probe, where it is converted into a form suitable for transfer to the surface, and then goes to one of the inputs of the dividing system 10 implementing the operation of dividing the voltage proportional to Uoo by the voltage proportional to the probing current, in accordance with the formula. The output of the dividing system 10 produces a voltage proportional to the measured electrical resistivity, not distorted by the effect of the remote electrodes.

In an embodiment of the computing unit 9 of FIG. 2 voltage from the output of the transformer 1 1, the displacement UN.,. is supplied to the voltage divider 13, consisting of resistors 14 and 15 with a division factor equal to, from the output of the divider 13, a voltage proportional to kUiia, is fed to one of the inputs of the subtraction cell 12, to the other input of which comes from the output of the input transformer 5 life proportional to uni. In the subtraction cell 12, the subtraction operation is carried out:. From the output of cell 12, a voltage proportional to (kUjij, - Ujsjj) is fed to the input of a large-scale amplifier with a gain. At the output of the large-scale amplifier 16, a voltage proportional to

TJ ... kUM2 -UMI k-1

which is then fed to the input of the measuring transducer 6 of the probe potential.

A simpler and more acceptable embodiment of the computing unit 9 is shown in FIG. 3. The principle of operation of the computing unit is as follows. Taking into account the transformation ratios of the input transformers 1 1 and 5 of the probe potential equal to k, at the outputs of these transformers we obtain voltages proportional to, respectively

CTt

one

and.

k-I i By turning on the secondary windings of the input transformers 5 and 11, the counter, i.e., the beginning with the beginning or the end and the end, at the output of the oppositely connected windings, we obtain a voltage proportional to Uoo, which is then fed to the input of the measuring transducer 6 of the probe potential.

tzs

 f

  I- if3C

Computational unit

liz measuring probe potential

Auxiliary system

io

1

R

Computing unit

I Computational 1 Lok per8yi and Second

 Input potential transformers probe

L

I

FIG. 2

Claims (3)

1. A Lateral Well Logging Device, including an alternating current generator, a side logging probe, first and second remote electrodes, a first input potential transformer of a probe, a potential transducer of a probe, an input current transformer of a probe, a measuring transducer of a current of a probe, a computing unit and a dividing system, moreover, the input of the side logging probe is connected to the output of the alternator, the first output of the side logging probe is connected to the input of the input transformer of the probe current, for which it is connected to the input of the measuring probe current transducer, the second output of the side logging probe is connected 'to the first input of the first input transformer of the probe potential, the output of the measuring probe current transducer is connected' to the first input of the dividing system, characterized in that it has a remote remote electrode, the second input of the first input the probe potential transformer is connected to the first remote electrode, the first and second outputs of the first input probe potential transformer are connected to the first third inputs of the computing unit and the first and second outputs of the second input transformer - respectively to the second and fourth inputs of the computing unit, the first and second outputs of the computing unit are connected to first and second inputs of the transmitter the probe potential and the output of the latter is connected to a second input of the separating system. 2. The device according to π. 1, characterized in that the computing unit contains a voltage divider, a subtraction cell and a scale amplifier, the first input of the computing unit being the first input of the subtracting cell, the second input of the computing unit the first input of the voltage divider, the third and fourth inputs of the computing unit the third input. output is disconnected from the subtraction, the output to the input is scaled to, in order to simplify the design and increase operational reliability, an additional transformer than the first transformer is introduced second the input potential of the probe, the input of the second input potential of the probe is connected to the second output of the lateral logging probe, and the second input is connected to the second voltage divider, voltage suppressor, by the red cell input of the connected amplifier, and the outputs of the latter are the outputs of the computing unit, in addition, the coefficient a voltage divider dividing k is 1 _Hr / l _Si, where l _Kz - distances respectively from the first and cerned remote probe electrodes to the center of laterolog and gain scaling amplifier equal to - ^ W-. 3. The device according to π. 1, characterized in that the computing unit is made in the form of a first and second input potential transformer of the probe, the first output of the first input potential transformer of the probe connected to the first output of the second potential transformer SU ... 1188690> probe, the second output of the first input transformer of the potential of the probe is the first output of the computing unit, and the second output of the second input transformer of the probe potential is the second output of the computing unit, the first outputs of the first and second input transformers of the potential of the probe are the beginnings or ends of their secondary windings, and the ratio of transformation coefficients of said transformers is equal to k.