RU1790773C - Geoelectrical surveying generator device - Google Patents

Abstract

Usage: in geophysics, in electrical exploration installations during geophysical work using the dipole profiling method, VES method, frequency sounding method, etc. SUMMARY OF THE INVENTION: A synchronous digital filter, the basis of which is a multiplier, is introduced into the generator device. Samples of a harmonic signal are supplied to one input of the multiplier, and to the other, an amplified voltage proportional to the load current. By comparing the control voltage from a synchronous digital filter with a reference voltage, the control pulses are generated to stabilize the current. The use of a generator device for electrical exploration allows to increase the productivity and accuracy of measurements, obtain operatively necessary information, and also makes it possible to conduct research in hard-to-reach places. 3 ill. ate

Description

The invention relates to geophysics and can be used in electrical exploration installations.

Generator devices are known for geophysical exploitation using alternating current, for example, a generator-emitting device for electrical exploration.

To stabilize the current, the device comprises a master oscillator connected in series with a frequency divider, a power amplifier, an emitter. The emitter is connected through a feedback circuit to the input of the AC / DC converter to a constant, the output of which is connected to one of the inputs of the comparison circuit. The output of the reference voltage source is connected to another input of the comparison circuit. The output of the comparison circuit is connected to the control input of the controlled voltage divider.

The disadvantage of this device is that the stabilization of the amplitude of the current occurs in a narrow range of Frequency. low performance.

A more perfect and close to the invention in terms of technical nature and the achieved result is a generator-emitting device for electrical exploration.

The device contains a serially connected master crystal oscillator, a frequency divider, a controlled voltage divider, a selective amplifier

Xj

u o

XI XI СО

with

power, emitter, feedback signal pickup element, amplitude detector connected to one of the inputs of the comparison circuit, the first input of which is connected to the other input, and the low-pass filter output, the input of which is connected to the controlled input of the controlled divider, for example. Additionally, the device comprises a phase detector, a second reference voltage source, a second comparison circuit, and a second low-pass filter.

A disadvantage of the known device is that obtaining a harmonic (sinusoidal) signal for these studies is associated with a significant deterioration in the overall dimensions of the equipment; In addition, low research productivity,

The aim of the invention is to increase the measurement performance due to the ability to work in a wide frequency range.

When using the proposed generator device for geoelectrical exploration, it is possible to quickly obtain the necessary information, as well as conduct research in hard-to-reach places.

This goal is achieved in that the generator device for geoelectrical exploration, including sequentially connected generator, shaper, addition circuit, output device in the form of a bridge circuit with a load in the diagonal, connected in series with a current sensor, the output of which is connected through an isolation circuit to the input of the amplifier and also a comparison circuit, the output of which is connected to the second input of the addition circuit, according to the invention, comprises a multiplier, read-only memory (ROM), a matching circuit, and reference voltage source, timing device, wherein the generator output is connected to synchronization inputs of the reference voltage source and timing device, whose output is connected via ROM to the second input of the harmonic signal of the multiplier, the first input of the current signal of which is connected to the output of the amplifier, and the output the multiplier is connected via a matching circuit to the information input of the comparison circuit, the reference input of which is connected to the output of the reference voltage source.

From the spectrum of the emitted signal, the first harmonic component of the current is extracted, which is the object of study. To stabilize the current of the first harmonic, a signal is filtered that is proportional to this current.

Probing signals are generated by a generator. An information signal is received by the receiver on the first harmonic component (the receiving device is not considered in this case).

The change in the waveform occurs when filtering a rectangular alternating pulse, i.e. separation of the first harmonic component from the complex signal spectrum. A multiplier, a ROM, and a clock device introduced into the device make it possible to replace analog filters and obtain a wide range of operating frequencies in one device.

In FIG. 1 is a structural diagram of a generator device for geoelectrical exploration; in FIG. 2-diagrams of his work; in FIG. 3 - diagrams of the multiplier.

The generator device for geoelectrical exploration contains a generator 1, forming a grid of operating frequencies, from the output of which the selected frequency is fed to the input of the shaper 2. The output of the shaper 2 is connected to the input of the addition circuit 3, the output connected to the input of the output device 4 in the form of a bridge circuit with a load in the diagonal 5 the current sensor (not shown) in series with. The signal from the current sensor through isolation circuit 6 and amplifier 7 is fed to one input of multiplier 8, to the other input of which are samples of the harmonic signal recorded in ROM 9. The voltage from the output of multiplier 8 through matching circuit 10 is fed to the information input of comparison circuit 11 , to the reference input of which voltage is supplied from the reference voltage source 12. The operation of the ROM 9 is synchronized by a timing device 13, which is connected to a generator 1, which also controls the operation of the reference voltage source 12.

The operation of the proposed device in the mode of stabilization of the current of the first harmonic is as follows.

(See diagrams of FIG. 2). The signal A (Fig. 2) from the generator 1 is supplied to the driver 2, which generates the paraphase control pulses B1 and B2, necessary for the operation of the bridge circuit 4, and also provides protection against the passage of through current through the key elements of the bridge circuit 4. These pulses, entering through addition circuit 3 to the bridge circuit

4, cause alternately tipping over his shoulders. As a result of this, alternating current pulses I flow through the load 5 (Fig. 2). A voltage proportional to the load current is amplified by the amplifier 7, applied to the current input of the multiplier 8, and has the form 1 (see Fig. 3). To the other input of the multiplier 8 from the ROM 9 are the samples of the harmonic signal corresponding to the first harmonic component 2 (Fig. 3). The amplitude of the samples is calculated by the formula

U Um sin cot,

2tg

where O) - - is the step of the cyclic frequency;

n is the number of samples in the period.

The control circuit 13 generates clock pulses 4 (Fig. 3). The output signal of the multiplier 8 has the form 3 (Fig. 3). The voltage at the information input of the comparison circuit 11, which is proportional to the actual amplitude value of the first harmonic E (FIG. 2), is compared with the reference voltage F of the reference voltage source 12 in the comparison circuit 11. B

as a result, control pulses C are generated which are necessary to stabilize the current in load 5.

Let the current in the load decrease as a result of any cause. Then the amplitude of the signal at the input of the multiplier 8 decreases. Accordingly, the effective voltage E at the output of the matching circuit 10 will decrease.

of this, the pulse duration C at the output of the comparison circuit 11 will increase, go to the addition circuit 3, and increase the current flow time through the load 5, i.e. its current value. Since acting and

Since the amplitude value of the harmonic signal is related to a known dependence, it can be considered that the amplitude of the first harmonic component of the current flowing through the load 5 is stabilized.

Compared with the prototype, the proposed device increases the measurement performance in a wide range of frequencies, it is possible to quickly obtain the necessary information, and

also conduct research in hard to reach places.

Claims (1)

SUMMARY OF THE INVENTION A generator device for geoelectrical exploration, comprising a series-connected generator, a driver, an addition circuit, an output device in the form of a bridge circuit with a load in the diagonal connected in series with a current sensor, the output of which is connected to the amplifier input through an isolation circuit, and a comparison circuit. the output of which is connected to the second input of the addition circuit, characterized in that, in order to increase productivity, it contains a multiplier, a constant memory triad (ROM), a comparison circuit, a reference voltage source, a timing device, the generator output being connected to the synchronization inputs of a reference voltage source and a timing device, the output of which is connected via a ROM to the second input of the harmonic signal of the multiplier, the first input of the current signal of which is connected with the output of the amplifier, and the output of the multiplier is connected via a matching circuit to the information input of the comparison circuit, the reference input of which is connected to the output of the reference voltage source. f, - „- rAgrHJIimi i ..." and - --- I ge ") 1 --.- l -.- - --Jwc r „. - -v GG-G1 I I JTaii "wr i", (l T  j-sm AKTWpertwfc.- I „, J“ i m-t1 G f- t L. .J d TT GGT GP f - ... p.: doevc1% 01I Jzl - -v-Ј f I „,.-I.“ K-i.-. f- t L. .J i i SHShZhL AND