SU1059157A1 - Azimut converter for remote measuring system - Google Patents

Abstract

AZIMUTH CONVERTER FOR THE TELEASIS OF AN EPELINE SYSTEM, comprising a generator, an azimuth sensor, made in the form of two orthogonal differential flux-probes, switch four. a key, an amplifier and an integrator, in order to improve accuracy, it is equipped with a frequency divider, a frequency amplitude converter, a time interval, three additional keys and a current limiter, while the frequency divider is on between the generator and the azimuth sensor, Two keys are connected to one signal line to the signal windings of the sensor, the third key is connected to the common wire cxeN "through one current limiter, the fourth and fifth keys are also connected to the integrator input by one differential circuit, the other outputs of these five keys are interconnected, the sixth switch is connected in parallel to the capacitor of the integrator and the seventh switch is on between the amplifier and the amplifier; there is a time interval that controls the inputs of the fourth and fifth Keys are connected to the generator and the rest of the keys to the switch, the integrator output is connected to the amplifier input, the output of the converter amplitude - time interval is the device output. . ate with

Description

The invention relates to promiscule geophysics and is intended for use in geophysical telemetric systems, can use P stand alone and cable inclinometers, as well as / with small additions, as an independent device.

A device for determining the magnetic heading, comprising a magnetic field sensor connected by output windings through a series-connected summing element, a filter and a forming unit to a time interval unit, and excitation windings connected to a phase shifter, a generator, a counter, a key and a shaping unit, as well as frequency dividers are known. the input of one of which is connected to the generator, and the output to the time interval block and the input of the other frequency divider, the output of the latter through the formation of the block is connected to the phase detector m fl.

An electronic compass is also known. It contains a ring ferrosonde and doubles the frequencies connected to the generator output, two conversion channels consisting of a series-connected selective amplifier, a phase detector and an amplifier, signal windings of the fluxgate are fed to the inputs of the conversion channels, and the indicator doubles to the inputs of the conversion channels frequency is connected to the control inputs of the G2 phase detectors.

The disadvantage of these devices is the considerable temperature error caused by the temperature drifts of filters and selective amplifiers, as a result of which the devices have low measurement accuracy when operating under conditions varying over wide limits of the ambient temperature.

Closest to the invention is an azimuth converter for a telemetric system comprising a generator, an azimuth sensor, made in the form of; two orthogonal differential flux probes, a switch, four switches, an amplifier, and an integrator C.

The disadvantages of the known device are the complexity of the design, as well as the low accuracy of measurement of parameters due to the large amplitude and phase drifts of the filters and phase splitters, which are located in the squalash device and are exposed to high temperatures. In addition, the device has a low speed, which is limited by large constant filters and integrator, and phase splitter

The aim of the invention is to improve the accuracy

This goal is achieved by the fact that a device containing a generator, azimuth sensor, made in the form of two orthogonal differential (; p rozondov, switch, four keys, amplifier and integrator, is equipped with a frequency divider, amplitude converter - time interval, three additional switches and current limiter , while the frequency divider is connected between the gene €; rator and azimuth sensor, two keys are connected at the same terminals to the signal windings of the azimuth sensor, the third key is one output à € fez current limiter Connected to the common wire, the fourth and fifth keys are also connected by one of the outputs to the integrator input, made in a differential circuit, other outputs of the five keys are connected to each other, the sixth switch is connected in parallel to the integrator's capacitor, and the seventh switch is connected between the amplifier and the converter r1 amplitude is the time interval, controls the inputs of the fourth and fifth keys are connected to the generator, the rest of the keys are connected to the switch, the integrator output is connected to the amplifier input and the output of the converter The magnitude - time interval is the output of the device.

On | Я1Г, 1 the functional diagram of the converter is presented; FIGS. 2 and 3 are temporary charts of device operation.

The azimuth converter contains a generator 1, connected through a divider 2 frequencies to the excitation windings of the azimuth sensor 3 (orthogonal differential flux probes), electronic keys 4–10, of which the keys 4 and 5 are connected to the signal windings of the azimuth sensor 3, a key with one output h €; the current limiter 11 is connected to the common wire of the circuit, the keys 7 and 8 are also the same pins. . connected to the inputs of the integrator 12, made according to the differential circuit, the other outputs of the keys 4-8 are interconnected, CLT 9 is connected in parallel to the capacitor of the integrator 12, Controls the inputs of the keys 7 and 8 are connected to the generator 1, the rest of the keys to the outputs of the switch 13, the key 10 is connected between the amplifier 14 and the converter 15 amplitude - the time interval, the output of the integrator 12 is connected to the input. Amplifier 14, the second input of the converter 15 alpshituda - the time interval and the control input of the ko motator are combined and form stroke device for clock pulses from the external oscillator device operates sleduyuyutm manner. The generator 1 absorbs an azimuth sensor with a variable voltage of the frequency Wg / 2 f through the exciter winding divider 2 and also provides antiphase control pulses to the control inputs of the keys 7 and 8 with the frequency w. As a result of the interaction in the cores of the flux-gates of alternating magnetic flux induced by the alternating excitation current and the constant horizontal component of the magnetic field SeNtnH on the secondary signal windings of the fluxgons, even harmonic voltages arise (in contrast to the excitation frequency WB / 2 f the harmonics are proportional to the harmonics, the amplitudes of which harmonics equal to the excitation frequency WB / 2f are proportional to the amplitude of which harmonics are proportional to the amplitude of the amplitude of which along the WB / 2 f excitation frequency of which harmonics are proportional to the amplitude of the amplitude of which along harmonics is proportional to the amplitude of the amplitude of the WB / 2 f excitation frequency of which harmonics are proportional to the amplitude of the amplitude of which harmonics are proportional to the amplitude of the harmonic voltage across the excitation frequency WB / 2 f of harmonic proportions. rotation of the sensor at one ferrosoal and cosine of the angle of rotation of the other.Therefore, the voltage on the signal winding of one of the flux-probes can be written as Ug. 3inct {U n "; 3t U, jSb2Wgt and jSiri 3u) gt-v ... + j, (- 1 for the second fluxgate. U co3cC (, gt.U, jSin2" gt U ,. Sin3Wpt4 ...- j , (2 where ° C is the azimuth-, {r, -,. Amplitude corresponding to the harmonics of the output voltage of ferrosons. Yes. FIG. 2 shows the oscillogram of the output voltage U of the sensor, At time t (FIG. 3) the back, the front of the first clock pulse Uj is opened. switches 9 and 10 are controlled by voltages and Ujnp 10 (Coming from the switch 13 f and the zero of the control voltage corresponds to the open state of the key. P The total discharge of the integrator capacitor, Taj is that by the time t the voltage across the capacitor is zero. At time 12, key 4 opens and voltage U is applied to keys 7 and 8, which alternately commute with the frequency tog via phase signals from generator 1 , as a result, the voltage at the outputs of squares 7 and 8 (or the inputs of the integrator 12J and the mesh is a kind of unipolar pulses u5g, -7, sBbrxB voltage and i5v. "they bore at the inputs of the integrator 12. As the integrator is made according to the differential scheme , its output voltage in the time integral can be It can be represented as s VB / X-12 RC J sBbK7 s VYCH8 / o. or taking into account 1 and 2 2i „. I and „- stnoCH-e 5 OUT tt Л 4-т в - т% tv..4 X Slnotd-t where Rc. constant time integra. , rator 12. Considering that the integrator time constant is much longer than the time interval t2, we can ignore the variable component of the output voltage and write -I LLsbotll-e sebix-fi jj the output voltage of the integrator is amplified by amplifier 14 and receives a positive offset U, as a result, the output voltage of the amplifier is bf, ee Seb (X-f4 (- amplifier gain)). The voltage from the output of amplifier 14 through the switch 10 is fed to the input of the converter 15, the amplitude is the time interval 15, when the second clock appears shtul a, arriving at the second input of the converter 15, in the interval c, the analog signal from the amplifier 14 is sampled and converted into a time interval where 15, respectively, the conversion factor and the initial time interval at JBb, O, At time t, on the trailing edge the clock pulse closes key 4 and opens key 9, through which the capacitor in integrator 12 quickly discharges to zero, at time tg key 5 opens and key 9 closes, and in the interval t, - ty integration occurs and signal transformation and taken from the second fluxgate.

Here, similarly (61, output. The voltage of amplifier 14 is written

And the corresponding time interval when sampling the signal in the interval

Chotg will present as

(eleven)

corresponding time interval

from 5 eBYx14 o -G

(uh

In the time interval tj-t, the capacitor charge in the integrator 12 is reset via switch 9, and at time tg, through the switch voltage, switch b and resistor 11, the integrator inputs are connected to the common wire of the circuit, resulting in the slider voltage of the amplifier

about B617 (4 lw I

(-"about;

N -N "N

The circuit provides three values of the time interval, corresponding to the sensor signals and some initial signals (i conversion channels, from which the values of the desired azimuth angle can be obtained by filling the time intervals with high frequency pulses with a conversion factor K and calculating the azimuth angle in the external calculator using the formula

„,).

where N is the corresponding time intervals Tg f 7 C I О Thus, the azimuth is determined by the relative signals of the two ferrodes, and when the intervals t2 and tcf are equal, which is performed with great accuracy, does not actually depend on the circuit parameters. The azimuth converter differs from the known device in that it allows to reduce to zero the influence of the main influence on the factor circuit - ambient temperature, which during operation varies over wide limits. As the expression (12) shows, the measurement result does not depend on the coefficients of the transformation of the elements K 4 and the initial values 0. and fo, which vary under the influence of the temperature around it. environment. The measurement result does not depend either on the change in the exponent of the time intervals C 1 Vt, tg-1), vt2 (t, - tj., -18) and the duration of tactical pulses {sample duration /,

(R) The main and only condition for maximizing the accuracy of the conversion is the constant ratio of the durations of the clock pulse, the discharge interval of the capacitor in the integrator 12 (t). and the time interval of the charge of the condenser catopa (tj) for the period of clock pulses and within the operation cycle of the converter j. This condition is fulfilled with great accuracy and when the frequency of the clock pulses changes, so does the BpjSMH cycle: This standing pulse can be considered constant. The device has high performance due to the fact that the charge time of the capacitor in the integral is chosen to be 3. significantly less than the constant charge fj (i.e., the capacitor is charged Not to a steady-state and to some intermediate voltage corresponding to time t, , t, t. This allows an increase in the frequency of clock pulses, i.e., speed, and is possible only if there is a key 9 through which the capacitor is quickly and completely discharged before each subsequent charge. the integrator capacitor also contributes to the accuracy of the conversion, since by the time of 2 S at the beginning of each subsequent charge the scheme is reduced every time to the same initial conditions, which eliminates the uncertainty from the inequality of the initial conditions of the capacitor and the capacitor.

The azimuth transducer is distinguished by its simple design due to the small number of elements.

in comparison with the known device, and practically does not require adjustment, since the errors of operation are eliminated when calculating the values of the azimuth.

The preliminary atomic HctM values of the proposed device showed that it provides accurate measurement of azimuth 11 in dia; temperature range around the environment O - 130 ° C. At the same time, the accuracy of the device as a whole is determined only by the accuracy of balancing the sensor.

G-FT, g

Claims (1)

Azimuth Converter for Telemetry System, comprising a generator, an azimuth sensor, made in the form of two orthogonal differential flux probes, a four-key switch, an amplifier and an integrator, which, in order to increase accuracy, it equipped with a frequency divider, an amplitude converter, a time interval, three additional keys and a current limiter, while the frequency divider is connected between the generator and the azimuth sensor, two keys are connected by one terminal to the signal signal windings of the sensor, the third key is connected to the common circuit via a current limiter, the fourth and fifth keys are also connected to the inputs of the integrator using the differential circuit, the other outputs of these five keys are connected to each other, the sixth key is connected * in parallel with the integrator capacitor and the seventh key included - between the Amplifier and the converter, the amplitude is the time interval, the control inputs of the fourth and fifth keys are connected to the generator, and the remaining keys to the switch, the integrator output with It is connected to the input of the amplifier, the output of the converter is the amplitude - time interval is the output of the device. SU ,,,, 1059157>