RU2100594C1 - Method of determination of well direction and inclination and gyroscopic inclinometer - Google Patents

Abstract

FIELD: precise instrumentation engineering; applicable in investigation of oil, gas and geophysical wells by moving downhole instrument in well in continuous or point mode, in determination of well direction and inclination with simultaneous measurement of temperature inside downhole instrument and angle of turning of its body relative to well axis. SUBSTANCE: method and inclinometer are based on gyroscopic stabilizer whose platform carries rigidly connected acceleration measuring devices with angular velocity measuring devices on the basis of two-degree-of-freedom gyro. In mode of setting, platform is rotated at constant angular velocity and upon processing of signal of angular velocity measuring device, the initial orientation of axes of sensitivity of acceleration measuring devices in direction is determined. In motion of downhole instrument, direction and inclination are determined by recording signals of acceleration measuring devices. On the basis of recorded signals, at each step of computing device operation, matrix of orientation is formed in form of product of matrix orientation increment by matrix of orientation at the previous step. Orientation matrix is constructed as function of orientation angles which are determined at each step by the signal of acceleration measuring devices. Obtained information is processed and transmitted by the unit of digital processing which, by each analog input, consists on connected in series voltage-frequency converters and reversible counters, and by digital input/output, has transceiver of successive code. Unit of digital processing is controlled by built-in single-crystal microcomputer with four programmed two-directional ports. EFFECT: higher efficiency. 5 cl, 4 dwg

Description

 The invention relates to precision instrumentation and can be used, for example, for the inspection of oil, gas and geophysical cased and uncased wells by moving the downhole tool in the well in continuous or spot modes.

 A known method for determining the azimuth of a cased hole at successive points using a gyroscopic inclinometer (ed. St. USSR N 1548423, class E 21 B 47/02, Bull. N 9, 03/03/90), which includes sequential operations: leveling a three-stage gyroscope, determining the angle between the axis of the inclinometer and the vector of kinetic moment of a three-degree gyroscope, i.e., the azimuth angle, and converting this angle into an electrical signal using an inductive sensor.

 There is also a method of determining the azimuth of a cased hole at successive points using a gyroscopic inclinometer (RF patent N 2030574, CL E 21 B 47/02, Bull. N 7, 03/10/95), which improves the above method in terms of determining and compensating for the drift of three-stage gyroscopes on the basis of which angular velocity meters are built around three mutually perpendicular axes.

 Both methods do not allow for well inspection during continuous movement of the downhole tool, which reduces the performance of inclinometric work.

 There is also a method of continuous inspection of a well, taken as a prototype, which allows you to measure the azimuth and zenith angle of the well and which is implemented in an inclinometer (RF patent N 2004786, class E 21 B 47/02, Bull. N 45-46, 15.12.93) . The specified method is based on measuring accelerations relative to two mutually perpendicular axes, measuring angular velocities relative to two mutually perpendicular axes, coinciding with the axes of measuring accelerations, on measuring the angle of rotation of the downhole tool relatively stabilized in the horizontal plane and in the azimuth of the direction constructed by a three-stage gyroscope. Moreover, in the initial exhibition mode, all five of the above operations are used in combination with algorithms that, in structure, represent trigonometric equations corresponding to angular velocity measurement signals, and an expression for calculating the cardan error, which includes anti-aircraft and apsidal angles determined from acceleration measurements, and the angle of rotation of the downhole tool around the longitudinal axis relative to the stabilized direction. As a result of the operation of the initial exhibition algorithm, the azimuth of the stabilized direction is determined (azimuth of the main axis of the three-degree gyroscope). In the mode of measuring the orientation parameters of the well (azimuth and zenith angle) during continuous movement of the downhole tool, operations of measuring accelerations, measuring the angle of rotation of the downhole tool around the longitudinal axis, the azimuth value of the main axis of the gyroscope calculated and stored in the initial exhibition mode, as well as the azimuth and zenith angle of the well. Since in this case the azimuth of the well is measured in the horizontal plane, and the angle of rotation of the downhole tool around the longitudinal axis deviated from the local vertical by the zenith angle, the trigonometric expression for calculating the cardan error is the basis of the algorithm to compensate for the methodological measurement error. In the formation of the well azimuth (inclination plane), algorithmic compensation of the vertical component of the angular velocity of the Earth’s rotation and the systematic component of the angular velocity of the gyro drift is carried out.

 However, in the prototype method, as well as in analog methods, the acceleration measurement is carried out by acceleration meters rigidly mounted on the body of the downhole tool, which gives rise to additional errors in the continuous measurement mode, since the acceleration meters are involved in the rotation of the downhole tool around the longitudinal axis.

Known gyroscopic inclinometers (Uttect G.U. de Ward J.P. New gyroscope for geophysical research. Oil, gas and petrochemicals abroad, 1983, N 3, pp. 14-19; RF patent N 2030574, class E 21 B 47/02, Bull. N 7, 03/10/95), built on the basis of blocks of accelerometers (accelerometers) and angular velocity sensors (angular velocity meters) based on three-stage gyroscopes, for example, dynamically tuned gyroscopes that are rigidly fixed to the borehole housing device. At the same time, the angular velocity sensors in the gyroinclinometer (RF patent N 2030574) during the formation of the measuring information set each sensor in series in two positions, differing from each other by a rotation of 180 ^o relative to the axis perpendicular to the axes of measurement of angular velocities.

 Along with the block of acceleration and angular velocity meters, the gyroinclinometer contains a ground computer, which is connected by a wireline cable to the acceleration and angular velocity meter. The indicated inclinometers have the following disadvantages: the inclinometer works only in spot mode, which increases the time for examining the wells and leads to a decrease in the productivity of inclinometric work.

 A gyroscopic type inclinometer is also known (RF patent N 2004786, class E 21 B 47/02, Bull. N 45-46, 15.12.93) containing a ground-based computer and a downhole tool connected to it by a wireline cable, comprising a meter fixed to the body accelerations along two mutually perpendicular axes, and an angular velocity meter along two mutually perpendicular axes, for example, based on a dynamically tuned gyroscope, the sensitivity axes of which are parallel and perpendicular to the longitudinal axis of the downhole tool, a three-degree gyroscope with a sensor com angle along the outer axis directed along the longitudinal axis of the downhole tool and the correction circuit for leveling the main axis of the gyroscope in exhibition mode. The outputs of two-component acceleration and angular velocity meters, the output of the three-stage gyroscope angle sensor are connected by a wireline cable to a ground computer equipped with a compensation unit for the visible gyro drift and its drift systematic component, as well as a motion exhibition setting mode dial.

 The feature of the inclinometer of the prototype is as follows. In the exhibition mode, the rotor axis of the leveling system is brought into a horizontal position. Using the signals of acceleration meters, angular velocities and an angle sensor of a three-stage gyroscope, the azimuth of its main axis is analytically calculated and stored in a ground computer.

 In motion mode, the horizontal correction of the three-stage gyroscope is turned off and the azimuth and zenith angle of the well are analytically formed by the signals of its angle sensor and acceleration meters.

 This inclinometer has several disadvantages. Since acceleration meters are rigidly fixed to the body of the downhole tool, in the continuous movement of the downhole tool in the well, additional errors arise due to its rotation around the longitudinal axis. In addition, with automatic compensation of the angular drift velocity of a three-stage gyroscope, it is not taken into account that when the zenith angle changes, the angle between the rotor axis and the axis of the gyroscope outer frame will change, affecting the magnitude of the angular drift velocity, which is not reflected in the algorithms. The description of the invention also does not indicate the hardware for converting and transmitting information from angular velocity acceleration meters and an angle sensor of a three-stage gyroscope to a ground computer, which also affect the accuracy of determining the azimuth and zenith angle.

 The objective of the invention is to increase the accuracy of determining the azimuth and zenith angle of the well during continuous movement of the downhole tool in the well.

где i+1 текущий шаг работы вычислителя:
b $\genfrac{}{}{0ex}{}{\text{i+1}}{\text{lq}}$ , l, q ∈ [1,3] элементы матрицы ориентации, которую формируют в виде произведения матриц,
Bⁱ⁺¹ = ΔBⁱ⁺¹•Bⁱ,
где Bⁱ, Bⁱ⁺¹ матрицы ориентации на предыдущем и текущем шагах работы вычислителя;

приращение матрицы ориентации, элементы которой определяют в зависимости от углов ориентации θ_x, θ_y, θ_z по формулам

где ω $\genfrac{}{}{0ex}{}{\text{уп}}{\text{др}}$ угловая скорость дрейфа осей чувствительности измерителей ускорений и угловой скорости относительно оси стабилизации;
Ω $\genfrac{}{}{0ex}{}{\text{i}}{\text{уп}}$ проекция угловой скорости вращения Земли на ось стабилизации;

элементы матрицы ориентации, формируемые по результатам измерения проекций a $\genfrac{}{}{0ex}{}{\text{i+1}}{\text{x}}$ , a $\genfrac{}{}{0ex}{}{\text{i+1}}{\text{z}}$ ускорения силы тяжести g;
τ период дискретизации работы вычислителя, причем, начальное значение матрицы ориентации равно

где α_хв азимутальный угол осей чувствительности измерителей ускорения в момент окончания выставки,
для определения которого в режиме выставки вращают оси чувствительности измерителей ускорений и угловой скорости вокруг оси стабилизации с постоянной скоростью на заданный угол, измеряют в последовательных положениях угол поворота осей чувствительности измерителей ускорений и угловой скорости относительно корпуса, горизонтальную составляющую угловой скорости вращения Земли Ω_зг совместно с угловой скоростью дрейфа гироскопа относительно оси, являющейся осью чувствительности измерителя угловой скорости, по результатам измерений вычисляют среднюю угловую скорость вращения ω_в осей чувствительности измерителей ускорений и угловой скорости, систематическую составляющую угловой скорости дрейфа гироскопа ω $\genfrac{}{}{0ex}{}{\text{c}}{\text{др}}$ и формируют эталонную модель измеряемой угловой скорости ω_эj в виде
ω_эj = ω $\genfrac{}{}{0ex}{}{\text{с}}{\text{др}}$ + Ω_згsin(ω_в•j + Φ_x),
где Φ_x/ фазовый сдвиг;
j номер измерения,
и для оценки фазового сдвига вычисляют функцию невязки, представляющую сумму квадратов разности эталонной ω_эj и измеренной ω_j угловых скоростей на всем наборе измерений, которую минимизируют по фазовому сдвигу, а азимутальный угол α_хв оси чувствительности измерителя угловой скорости на момент окончания выставки определяют по формуле
α_хв = ψ_в- ψ₁+ α_x1,
где ψ₁, ψ_в углы поворота осей чувствительности измерителей ускорений (измерителя угловой скорости) относительно корпуса скважинного прибора вокруг оси стабилизации в моменты начала и окончания выставки;
α_x1 азимут осей чувствительности измерителей ускорения (измерителя угловой скорости) в момент начала выставки соответствует такому значению фазового сдвига Φ_x, который минимизирует функцию невязки.The problem is solved in that in the method for determining the azimuth and zenith angle of the well by means of a gyroscopic inclinometer, which includes measuring the acceleration of gravity along two mutually perpendicular axes, measuring the angular velocity relative to one of the above axes using a three-degree gyroscope, determining the initial orientation of the sensitivity axes of accelerometers in azimuth , calculation of azimuth and zenith angle of the well, sensitivity axis of accelerometers and angular velocity stabilization by about an axis coinciding with the longitudinal axis of the downhole tool, and at each step of the calculator operation when moving the downhole tool in the wellbore is determined azimuth and zenith angle of the borehole, for example, by the formulas

where i + 1 is the current step of the calculator:
b $\genfrac{}{}{0ex}{}{\text{i + 1}}{\text{lq}}$ , l, q ∈ [1,3] the elements of the orientation matrix, which is formed as a product of matrices,
B ^{i + 1} = ΔB ^{i + 1} • B ⁱ ,
where B ⁱ , B ^{i + 1} orientation matrixes at the previous and current steps of the calculator;

the increment of the orientation matrix, the elements of which are determined depending on the orientation angles θ _x , θ _y , θ _z according to the formulas

where ω $\genfrac{}{}{0ex}{}{\text{up}}{\text{dr}}$ the angular velocity of the drift of the sensitivity axes of the accelerometers and the angular velocity relative to the stabilization axis;
Ω $\genfrac{}{}{0ex}{}{\text{i}}{\text{up}}$ projection of the angular velocity of the Earth's rotation on the stabilization axis;

elements of the orientation matrix formed by measuring projections a $\genfrac{}{}{0ex}{}{\text{i + 1}}{\text{x}}$ , a $\genfrac{}{}{0ex}{}{\text{i + 1}}{\text{z}}$ acceleration of gravity g;
τ is the sampling period of the work of the calculator, and, the initial value of the orientation matrix is

where α _{xv is the} azimuthal angle of the axes of sensitivity of the acceleration meters at the end of the exhibition,
to determine which, in the exhibition mode, rotate the sensitivity axes of the acceleration and angular velocity meters around the stabilization axis with a constant speed by a given angle, measure in successive positions the angle of rotation of the sensitivity axes of the acceleration and angular velocity meters relative to the body, the horizontal component of the angular velocity of the Earth’s rotation Ω _zg together with the angular velocity of the gyro drift relative to the axis, which is the sensitivity axis of the angular velocity meter, according to the measurement results ychislyayut average rotation angular velocity ω _in sensitivity axes accelerometer and yaw rate, the systematic component of the angular velocity ω gyro drift $\genfrac{}{}{0ex}{}{\text{c}}{\text{dr}}$ and form the reference model of the measured angular velocity ω _ej in the form
ω _ej = ω $\genfrac{}{}{0ex}{}{\text{from}}{\text{dr}}$ + Ω _sg sin (ω _in • j + Φ _x ),
where Φ _{x /} phase shift;
j measurement number
and to estimate the phase shift, a residual function is calculated that represents the sum of the squares of the difference of the reference ω _ej and the measured ω _j angular velocities over the entire set of measurements, which is minimized by the phase shift, and the azimuthal angle α _{x in} the sensitivity axis of the angular velocity meter at the time the exhibition ends is determined by the formula
α _xb = ψ _in - ψ ₁ + α _x1 ,
where ψ ₁ , ψ _{in the} rotation angles of the sensitivity axes of the acceleration meters (angular velocity meter) relative to the body of the downhole tool around the stabilization axis at the moments of the beginning and end of the exhibition;
α _{x1 the} azimuth of the sensitivity axes of the acceleration meters (angular velocity meter) at the beginning of the exhibition corresponds to a phase shift value Φ _x that minimizes the residual function.

 In accordance with the method, a gyroscopic inclinometer was developed in which the uniaxial indicator gyrostabilizer performs stabilization of the sensitivity axes of acceleration meters and angular velocity meters. Thus, the task is solved in the device by the fact that a gyroscopic inclinometer, consisting of a downhole tool, equipped with an acceleration meter along two mutually perpendicular axes that are perpendicular to the longitudinal axis of the downhole tool, and an angular velocity meter relative to one of the two indicated axes in the form of a three-stage gyro along the axes of the suspension of which angular sensors and moment sensors are installed, the first angle sensor mounted on the axis of the suspension, which is the sensitivity axis, measure For angular velocity, it is connected through an amplifier of the contour of the angular velocity meter to the second moment sensor along the axis perpendicular to the angle sensor, a ground computer equipped with a compensation unit for the visible departure of the gyroscope and its drift systematic component, and connected by a wireline cable to the downhole tool, characterized in that the downhole the device contains a uniaxial gyrostabilizer, on the platform of which an accelerometer is rigidly mounted with sensitivity axes oriented perpendicular to the stub axis a gyro stabilizer, and a three-stage gyroscope, the second angle sensor of which is connected through a stabilization amplifier to a mining engine kinematically connected to the stabilization axis, on which the output angle sensor is mounted, made, for example, in the form of a sine-cosine transformer, and a digital processing unit, to the corresponding the inputs of which are connected the outputs of the gyro stabilizer angle sensor, the outputs of the acceleration meter and the output of the angular velocity meter, the first output of the digital processing unit being connected to the control the input input of the reference current master, the signal output of which is connected to the first gyroscope moment sensor located on an axis perpendicular to the stabilization axis, and the wireline cable is connected by its two inputs to the second and third outputs of the digital processing unit, which, for example, contains a single-chip microcomputer receiving a transmitter, three two-channel voltage-frequency converters and three two-channel reversible counters, and the ports P0 and P2 of a single-chip microcomputer programmed for input are connected by their input with the corresponding outputs of the least significant and most significant bytes of the data bus of the reverse counters, port P1 programmed for output, with bits P1.0 through P1.5, is connected respectively to the inputs of the selection enable and read permission of the corresponding reverse counters, bit P1.6 is connected to the polling inputs all reversible counters, and the discharge P1.7 is connected to the synchronization inputs of all voltage-frequency converters and reversible counters, the discharge of port P3.0, programmed to issue a control command, is connected to the first output of the unit As for digital processing, the inputs of the voltage-frequency converters are respectively the inputs of the digital processing unit, and the input / output of the serial input / output of a single-chip microcomputer through a transceiver is connected to the wireline cable and is the input / output of the downhole tool.

 To signal the temperature regime in the downhole tool, a temperature sensor is installed, which is connected to one of the inputs of the digital processing unit.

 In FIG. 1 shows a generalized kinematic diagram of a gyroscopic inclinometer and the relative position of coordinate systems at an arbitrary point in the well; figure 2 kinematic diagram of the gyrostabilizer and a block diagram of the communication of the downhole tool with a ground computer; figure 3 diagram of the position of the axes of sensitivity of the angular velocity meter in azimuth while rotating it around the axis of stabilization; figure 4 is an electrical diagram of a digital processing unit.

The following notation is introduced in the drawings:
1 downhole tool (SP);
2 logging cable, which carries out the descent and rise of the joint venture, the supply of electrical power, for example, the reception / transmission of information via a two-wire communication line with a serial code;
3 ground computer, for example, RS-486 type Note Book;
4 device for lifting and lowering the joint venture, for example, an electric winch with a collector;
5 uniaxial indicator gyrostabilizer (GS);
6 digital processing unit (BTsO);
7 secondary power sources (VIP), converting the ground power supply voltage into a set of voltages to ensure the operation of the joint venture (not shown in FIG. 2 for simplicity);
8 temperature sensor;
9 platform GS, the suspension axis OY _n which coincides with the longitudinal axis OY _with SP;
10 angle sensor of the platform platform, for example, a single-channel sine-cosine transformer type SKT-3250;
10.1 rotor of the angle sensor;
10.2 stator of the angle sensor;
11 a mining engine, for example, a torque sensor of the DM-5 type (direct current motor with excitation from permanent magnets);
12 angular velocity meter based on a three-stage gyroscope, for example, type D-7-OZM;
13, 14 acceleration meters, for example, small-sized type AT-1105;
15 amplifier channel measuring angular velocity;
16 stabilization amplifier;
17 reference current setter;
18 rotor of a three-stage gyroscope;
19 inner frame (BP) of a three-stage gyroscope;
20 outer frame (HP) of a three-stage gyroscope;
21, 22 angle and moment sensors relative to the suspension axis of BP;
23, 24 angle and moment sensors relative to the suspension axis of the HP;
25 zero risk of the rotor 10.1 determines the direction of the axis OX _p - the sensitivity axis of the angular velocity meter;
26- zero risk stator 10.2 determines the direction of OX _with SP;
27 single-chip microcomputer, for example, type КР1816 BE51, it has an integrated programmable ROM with a capacity of 4096 bytes, an internal RAM with a capacity of 128 bytes, 4 eight-bit bi-directional ports (P0, P1, P2, P3), a high-speed programmable serial port operating in multiplex mode;
28 transceiver, it can be implemented on optocouplers, moreover, the power of the communication line is the power of the VIP;
29, 30, 31 voltage-frequency converters (VFDs), two-channel are implemented in microassembly in housing 159 according to the standard scheme (documentation N ISMYA 431.321.001);
32, 33, 34 reversible counters are implemented on the LSI K1806 XM1-242, contain two autonomous channels with control and synchronization circuits, as well as output buffer registers.

The coordinate system adopted in figure 1-3, have the following notation:
OX _d Y _d Z _d terrestrial geographical coordinate system, with the axis OX _d oriented to the north (N), the axis OY _d oriented in the local vertical axis OZ _d complements the coordinate system to the right;
OX _with Y _to Z _{to the} coordinate system associated with JV housing, the OY axis is directed along _a longitudinal axis JV OX axis _oriented along the zero stator risks angle sensor 10, OZ axis coordinate system _with complements to the right;
OX _{n n} Y _n Z coordinate system associated with the construction platform (stabilized axis), wherein the axis OY _n stabilization axis (HS platform suspension axis); OX _p , OZ _p stabilized axes that are parallel to the sensitivity axes of the acceleration meters and oriented so that the coordinate system is right;
Ox _a , OZ _a the sensitivity axes of accelerometers 13 and 14, respectively;
OX _{g is} the suspension axis of the inner frame 19 of the gyroscope 12, which is also the sensitivity axis of the angular velocity meter (can be considered coincident with OX _p );
OY _{g the} axis of the suspension of the outer frame 20 of the gyroscope 12, which is parallel to the stabilization axis OY _p GS.

To explain the essence of the invention, the features of the operations of the method and the operation of the gyroscopic inclinometer in figure 1-3 the following notation:
ψ is the angle of rotation of the sensitivity axis of the angular velocity meter relative to the joint venture body (angle of rotation of the horizontal platform relative to the stabilization axis), respectively:
j ₁ angle of rotation at the start of the exhibition;
ψ _{j is} the rotation angle corresponding to the jth measurement, and j = 1-n;
ψ _g rotation angle corresponding to the nth dimension;
ψ _{to the} angle of rotation at the time of the end of the exhibition;
α _x azimuthal angle (azimuth) of the axis of sensitivity of the angular velocity meter (axis of the platform OX _p GS, sensitivity axes of acceleration meters) in this case:
α _x1 azimuthal angle at the start of the exhibition;
α _xv azimuthal angle at the end of the exhibition;
α well azimuth (the angle between the projections of the orth-J _{unitary enterprise} on OX _d Z _d and OX _d );
q zenith angle of the well;
W _sv = Ω _s sinΦ is the vertical component of the angular velocity of the Earth's rotation;
Ω _zg = Ω _z cosΦ is the horizontal component of the angular velocity of the Earth's rotation;
Ω _{z the} angular velocity of rotation of the Earth;
Φ _{c the} breadth of the location of the well;
ω _{dr the} systematic component of the drift of a three-stage gyroscope relative to the suspension axis of the inner frame, which coincides with the sensitivity axis of the angular velocity meter;
ω $\genfrac{}{}{0ex}{}{\text{eg}}{\text{dr}}$ the angular velocity of the drift axes of sensitivity of the acceleration and angular velocity meters (an estimate of the systematic component of the drift of a three-degree gyroscope along the axis of suspension of the outer frame) relative to the axis of stabilization.

The essence of the method for determining the azimuth and zenith angle of the well in accordance with the invention is as follows. First, SP 1 is lowered by means of a winch 4 at the wellhead by one to two meters and is held in vertical position with sufficient accuracy, while the sensitivity axes of the accelerometers OX _a and OZ _a are in the horizontal plane. For further explanation of the method, we consider successively two modes: the initial exhibition and the determination of the azimuth and zenith angle when the joint venture moves in the well.

 1. Initial exhibition.

In this mode, the initial position of the axes OX _a , OZ _a and OX _g in azimuth is determined.

Since the axes OX _a and OX _{g are} parallel, and the axis OZ _a is perpendicular to them, it suffices to carry out all the arguments about one axis, for example, the axis OX _g , which can be considered parallel to the axis OX _p . The algorithm of the initial exhibition is based on measuring the horizontal component of the angular velocity of the Earth's rotation in projection onto the axis of sensitivity of the angular velocity meter, rotating with a constant angular velocity. Consider the basic operations of the initial exhibition mode.

1.1. Rotate at a constant speed ω _in the sensitivity axis OX _a , OY _a and OX _p , while measuring and recording in successive positions the angle of rotation of the axis OX _g (OX _p ) ψ _j and the projection Ω _zg on the axis OX _p , which we denote ω _j , (j = 1-n).

где ψ₁, ψ_n начальное и конечное значения угла ψ_j (например, ψ_n- ψ₁ 360^o);
Δt время поворота на заданный угол.1.2. Calculate the angular velocity of rotation ω _in (figure 3)

where ψ ₁ , ψ _{n are the} initial and final values of the angle ψ _j (for example, ψ _n - ψ ₁ 360 ^o );
Δt rotation time at a given angle.

1.4. Формируют эталонную модель измеряемой угловой скорости, которая отражает физическую сторону измеряемой угловой скорости

где ω_в, ω $\genfrac{}{}{0ex}{}{\text{с}}{\text{др}}$ определяются выражениями (1) и (2);
Φ_x фазовый сдвиг.1.3. The average value of the angular velocity ω _j measured at n points is calculated, which corresponds to the systematic component of the angular drift velocity

1.4. Form a reference model of the measured angular velocity, which reflects the physical side of the measured angular velocity

where ω _in , ω $\genfrac{}{}{0ex}{}{\text{from}}{\text{dr}}$ defined by expressions (1) and (2);
Φ _x phase shift.

A further algorithm of the initial exhibition is to obtain the best estimate of the angle Φ _x , which corresponds to the azimuthal position of the axis OX _p at the time the exhibition starts, i.e. angle α _x1 .

, которая является функцией невязки;
вычисляют значение функции невязки при изменении фазового сдвига от 0 до 360^o с заданным шагом, который должен быть меньше погрешности измерения азимутального угла;
выбирают наименьшую величину оценки, а значение Φ_x, соответствующее минимуму оценки, принимают за значение азимута оси чувствительности измерителя угловой скорости в момент начала выставки, который обозначают α_x1.1.5. The best estimate is obtained for the phase angle Φ _x by the least squares method, while:
calculate the difference in angular velocities ω _ej - ω _j ;
calculate the estimate as the sum of squares

, which is a residual function;
calculate the value of the residual function when changing the phase shift from 0 to 360 ^o with a given step, which should be less than the measurement error of the azimuthal angle;
the smallest value of the estimate is chosen, and the value Φ _x corresponding to the minimum of the estimate is taken as the azimuth of the sensitivity axis of the angular velocity meter at the beginning of the exhibition, which is denoted by α _x1 .

1.6. Form the azimuthal initial angle of the axis of sensitivity of the angular velocity meter at the end of the exhibition (figure 3)
α _xb = ψ _in - ψ ₁ + α _x1 . (4)
The obtained value of α _{xb is} stored and used in the future to form the initial orientation matrix.

2. Determination of azimuth and zenith angle of the well (operating mode)
In time, this mode begins at the moment of the start of the SP launch into the well and continues all the time the well is examined.

In this case, the azimuth angle α _xv at the end of the exhibition and acceleration a _xa and a _za in the projection onto the gyro-stabilized axes OX _а and OZ _а (or the same as in the projection on the axis) is used as initial information for determining the azimuth and zenith angle OX _n and OZ _n ). The algorithm for processing these signals is based on the use of only a digital computer and represents a modified algorithm for determining orientation parameters in the classical scheme of a strapdown inertial navigation system, when three acceleration meters and three angular velocity meters are rigidly fixed to the body of a moving object. The formation of the orientation algorithm, when two acceleration projections are measured relative to the stabilized axes and their initial position is known, is the main novelty of the proposed method, which can be represented as a sequence of the following actions and operations (Figs. 1 and 3).

 2.1. Determination of the azimuth and zenith angle of the well according to one of the well-known algorithms (Isachenko V.Kh. Inclinometry of wells. M. Nedra, 1987, pp. 20-36).

из которой α и θ можно определить, например, по формулам

Данные формулы наиболее целесообразны, так как элементы (направляющие косинусы) b₁₂ и b₃₂ непосредственно определяются по сигналам измерителя ускорений.For this, it is necessary to compose a matrix of directional cosines, an orientation matrix B between the Earth’s OX _d Y _d Z _d and the axes of sensitivity associated with the sensitivity axes OX _a Y _p Z _a or OX _p Y _p Z _p coordinate systems, which in this case has the form

from which α and θ can be determined, for example, by the formulas

These formulas are most appropriate, since the elements (guiding cosines) b ₁₂ and b _{32 are} directly determined by the signals of the acceleration meter.

 2.2. The formation of the orientation matrix during the movement of the joint venture in the well.

где α_{хв =} угол между осями OX_д и OX_п на момент окончания выставки (см. выражение (4)).The mutual angular displacement of the coordinate systems OX _d Y _d Z _d and OX _p Y _p Z _p is ultimately determined by the angular velocity of rotation of the Earth, the angular velocity of the drift of the gyrostabilizer (due to the angular velocity of the drift of the gyroscope) and angular velocities due to the curvature of the trajectory of the joint venture when it moves in the well. If the initial value of the orientation matrix B is known, then finding the algorithm for constructing the increment of the orientation matrix ΔB, we can organize the iterative process of forming the orientation matrix. Since the method, by its ideology, relies on the use of a digital computer, the iterative process, of course, can be associated with the cyclogram of the computer's work (with a sampling period τ). Choosing the period t sufficiently small, one can always consider the formation of the matrix DB due to the final rotation by a small angle,
and then the relation will be fair
B _{i + 1} = ΔB _{i + 1} • B _i , (7)
where i + 1 is the current step of the calculator;
B _i , B _{i + 1} orientation matrices at the previous and current steps of the calculator;
ΔB _{i + 1 the} increment of the orientation matrix at the current step of the calculator, and, at the initial step (i = 0) B ₀ is equal to the identity matrix E, and

where α _{xv = the} angle between the axes OX _d and OX _p at the end of the exhibition (see expression (4)).

In this case, attention should be paid to the identity of the terminology: the angle between the axes OX _d and OX _p , the azimuthal angle of the platform, the azimuthal angle of the sensitivity axis of the angular velocity meter, the azimuthal angle of the sensitivity axes of the accelerometers, since all these axes are rigidly connected to the stabilized platform, which in the device implemented by a gyrostabilizer.

 2.3. The formation of the increment of the orientation matrix at the current step of the calculator.

,
а элемент b $\genfrac{}{}{0ex}{}{\text{i+1}}{\text{22}}$ определяется из свойства матрицы направляющих косинусов

В основу построения алгоритма вычисления элементов матрицы ΔB_i+1 положено практически оправданное предположение, что приращение матрицы ориентации обусловлено малым конечным поворотом, который определяется тремя углами ориентации θ_x, θ_y, θ_z, формируемыми в результате решения обратной задачи, когда известными являются соответствующие элементы матрицы ориентации и дрейф осей чувствительности измерителей ускорений, определяемый в процессе выставки (Для простоты записи в выражениях θ_x, θ_y, θ_z верхний индекс i+1 опущен).When constructing the algorithm, the initial information is the signals of the acceleration meter along two mutually perpendicular axes, which are stabilized with respect to the axis coinciding with the longitudinal axis of the joint venture. From physical considerations and matrix (5) it follows that

,
and element b $\genfrac{}{}{0ex}{}{\text{i + 1}}{\text{22}}$ determined from the property of the matrix of guide cosines

The basis of constructing an algorithm for calculating the elements of the matrix ΔB _{i + 1 is} based on a practically justified assumption that the increment of the orientation matrix is caused by a small final rotation, which is determined by three orientation angles θ _x , θ _y , θ _z formed as a result of solving the inverse problem, when the corresponding elements of the orientation matrix and the drift of the sensitivity axes of acceleration meters, determined during the exhibition (For simplicity, in the expressions θ _x , θ _y , θ _{z the} superscript i + 1 is omitted).

где ω $\genfrac{}{}{0ex}{}{\text{уп}}{\text{др}}$ систематическая составляющая угловой скорости дрейфа осей чувствительности измерителей ускорений, определяемая выражением (2) (в действительности оценка дрейфа происходит с применением цифрового фильтра в подрежиме "калибровка дрейфа" и в данном изобретении не рассматривается, а считается стандартной процедурой);
Ω $\genfrac{}{}{0ex}{}{\text{i}}{\text{уп}}$ = Ω_згcosα_x1b $\genfrac{}{}{0ex}{}{\text{i}}{\text{21}}$ + Ω_3в•b $\genfrac{}{}{0ex}{}{\text{i}}{\text{23}}$ - Ω_згsinα_x1•b $\genfrac{}{}{0ex}{}{\text{i}}{\text{22}}$ проекция угловой скорости вращения Земли на ось стабилизации;
b $\genfrac{}{}{0ex}{}{\text{i}}{\text{12}}$ , b $\genfrac{}{}{0ex}{}{\text{i}}{\text{32}}$
b $\genfrac{}{}{0ex}{}{\text{i+1}}{\text{12}}$ , b $\genfrac{}{}{0ex}{}{\text{i+1}}{\text{32}}$ , b $\genfrac{}{}{0ex}{}{\text{i+1}}{\text{22}}$ элементы матрицы ориентации, определяемые выражениями (9) и (10) на i-м и i+1-м шагах работы вычислителя;
b $\genfrac{}{}{0ex}{}{\text{i}}{\text{21}}$ , b $\genfrac{}{}{0ex}{}{\text{i}}{\text{23}}$ элементы матрицы ориентации, вычисляемые в соответствии с операцией матричного произведения (7) на предыдущем шаге.

where ω $\genfrac{}{}{0ex}{}{\text{up}}{\text{dr}}$ the systematic component of the angular velocity of the drift axes of sensitivity of the acceleration meters, defined by expression (2) (in reality, the drift is estimated using a digital filter in the "drift calibration" submode and is not considered in this invention, but is considered a standard procedure);
Ω $\genfrac{}{}{0ex}{}{\text{i}}{\text{up}}$ _Sr = Ω cosα _x1 b $\genfrac{}{}{0ex}{}{\text{i}}{\text{21}}$ + Ω _3v • b $\genfrac{}{}{0ex}{}{\text{i}}{\text{23}}$ - Ω _sr sinα _x1 • b $\genfrac{}{}{0ex}{}{\text{i}}{\text{22}}$ projection of the angular velocity of the Earth's rotation on the stabilization axis;
b $\genfrac{}{}{0ex}{}{\text{i}}{\text{12}}$ b $\genfrac{}{}{0ex}{}{\text{i}}{\text{32}}$
b $\genfrac{}{}{0ex}{}{\text{i + 1}}{\text{12}}$ b $\genfrac{}{}{0ex}{}{\text{i + 1}}{\text{32}}$ b $\genfrac{}{}{0ex}{}{\text{i + 1}}{\text{22}}$ orientation matrix elements defined by expressions (9) and (10) at the i-th and i + 1-th steps of the calculator;
b $\genfrac{}{}{0ex}{}{\text{i}}{\text{21}}$ b $\genfrac{}{}{0ex}{}{\text{i}}{\text{23}}$ orientation matrix elements calculated in accordance with the matrix product operation (7) in the previous step.

которая и является приращением матрицы ориентации, а углы ориентации θ_x, θ_y и θ_z определяются выражениями (11).Considering the orientation angles θ _x , θ _y, and θ _z as rotation angles that translate the matrix B _i into the matrix B _{i + 1} , the matrix of directional cosines corresponding to these angles is calculated (like matrix (5)). Expanding the elements of this matrix in a Taylor series and keeping terms in the decompositions to the second order of smallness (which is always permissible with an appropriate choice of the sampling time τ, we represent the resulting matrix in the form

which is an increment of the orientation matrix, and the orientation angles θ _x , θ _y and θ _{z are} determined by expressions (11).

 The above method for determining the azimuth and zenith angle of the well was implemented in a gyroscopic inclinometer, the operation of which we will consider in two modes corresponding to the method. In this case, the joint venture is lowered into the well by one or two meters, the longitudinal axis of the joint venture is set to a vertical position, ground power is supplied through the wireline cable, which the VIP converts into a set of voltages necessary for the operation of the main power supply, service electronics (amplifiers, generators for supplying angle sensors ) and BCO. Bringing the GS to working condition (dialing the gyroscope with the rotor of nominal speed, turning on the stabilization loop), the ground computer puts the SP in exhibition mode. Since the central control center works in all modes, we will consider the features of its functioning after explaining the main modes.

 1. The initial exhibition of gyrostabilizer.

начинает прецессировать вокруг оси OY_г гироскопа 12 с постоянной угловой скоростью, а контур стабилизации, состоящий из датчика угла 23, усилителя стабилизации 16, двигателя отработки 11, будет воспроизводить это движение поворотом платформы 9 (совместно с установленными на ней измерителями ускорений 13 и 14 и измерителем угловой скорости 12) вокруг оси стабилизации OY_п. Такое вращение необходимо, чтобы ось чувствительности измерителя угловой скорости OX_г (OX_п) составляла непрерывно изменяющийся угол относительно направления на север, которое соответствует Ω_зг. Вращение платформы осуществляется на заданный угол (например, 360^o). В процессе вращения в дискретные моменты времени, которые соответствуют повороту платформы приблизительно на один градус, производят измерения сигналов датчика углов 10 (напряжения U $\genfrac{}{}{0ex}{}{\text{j}}{\text{1}}$ = K_дуcosψ_j, U $\genfrac{}{}{0ex}{}{\text{j}}{\text{2}}$ = K_дуsinψ_j, где K_ду коэффициент передачи датчика углов) и сигнала измерителя угловой скорости, снимаемого с усилителя 15 контура измерения угловой скорости (U₅= K₅•ω_j, где K₅ коэффициент передачи по угловой скорости; ω_j/ измеряемая угловая скорость). Независимо от типа датчика сигналов напряжения U_m, m= 1-6, масштабируются и приводятся к стандартному уровню, например, ± 8 В. При вращении платформы 9 через равные интервалы времени происходит программный опрос датчика углов 10 и измерителя угловой скорости 12 (в действительности опрашиваются соответствующие реверсивные счетчики БЦО). Измерительные массивы (U $\genfrac{}{}{0ex}{}{\text{j}}{\text{m}}$ , j=1-n) записываются в ОЗУ наземного вычислителя 3. После поворота на заданный угол, например, на 360^o программно снимается сигнал управления платформой и вычислитель 3 переходит к подпрограмме обработки, записанной в ОЗУ информации. Сначала по напряжениям, снятым с СКТ U $\genfrac{}{}{0ex}{}{\text{j}}{\text{1}}$ и U $\genfrac{}{}{0ex}{}{\text{j}}{\text{2}}$ , вычисляется угол ψ_j и также записывается в ОЗУ. Далее начинает выполняться алгоритм начальной выставки в соответствии с пунктами 1.1-1.5, приведенными выше. После вычисления азимутального угла α_x1 на момент начала режима выставки вычислитель переходит к другим подпрограммам, обеспечивающим работу гироинклинометра (например, "калибровка дрейфа"). При пояснении работы гироинклинометра перейдем сразу к подпрограмме динамического ожидания, которая характеризует завершение режима выставки. После поступления команды на переход СП в режим движения происходит последнее измерение угла ψ = ψ_в, по формуле (4) вычисляется азимут осей чувствительности измерителей ускорения, а по выражению (8) элементы приращения матрицы ориентации ΔB¹ на начальном шаге работы алгоритма ориентации.After bringing the HS to its working position, the axis OX _p occupies an arbitrary position in azimuth. The angle measured by the angle sensor 10 continuously changes due to the drift of the horizontal _axis and the vertical component Ω _sound . After the command from the ground calculator 3 arrives at the beginning of the exhibition, the BCO (microcomputer 1) generates a control signal U _k , which through the discharge P3.0 of the port P3 and the first output of the BSC goes to the control input of the reference current master 17, from the signal output of which the reference voltage is issued ( current) to the torque sensor 22. Vector kinetic moment

begins to precess around an axis OY _g gyroscope 12 with a constant angular velocity, and the contour stabilization consisting of angle detector 23, the amplifier stabilization 16, engine mining 11 will reproduce a movement rotating platform 9 (together with the attached accelerometers 13 and 14 and angular velocity meter 12) around the stabilization axis OY _p . Such rotation is necessary so that the axis of sensitivity of the angular velocity meter OX _g (OX _p ) is a continuously changing angle relative to the north direction, which corresponds to Ω _zg . The rotation of the platform is carried out at a given angle (for example, 360 ^o ). In the process of rotation at discrete points in time that correspond to the rotation of the platform by approximately one degree, the signals of the angle sensor 10 (voltage U $\genfrac{}{}{0ex}{}{\text{j}}{\text{one}}$ = K _do cosψ _j , U $\genfrac{}{}{0ex}{}{\text{j}}{}$$\genfrac{}{}{0ex}{}{}{\text{2}}$ = K _do sinψ _j , where K _{do is} the transmission coefficient of the angle sensor) and the signal of the angular velocity meter taken from the amplifier 15 of the angular velocity measurement loop (U ₅ = K ₅ • ω _j , where K _{5 is} the angular velocity transmission coefficient; ω _{j /} measured angular velocity). Regardless of the type of sensor, voltage signals U _m , m = 1-6, are scaled and brought to a standard level, for example, ± 8 V. When the platform 9 is rotated at equal time intervals, a software polling of the angle sensor 10 and angular velocity meter 12 (in reality interrogating the corresponding reverse counters of the central monitoring station). Measuring Arrays (U $\genfrac{}{}{0ex}{}{\text{j}}{\text{m}}$ , j = 1-n) are recorded in the RAM of the ground computer 3. After rotation by a predetermined angle, for example, 360 ^o, the platform control signal is removed programmatically and the computer 3 proceeds to the processing subroutine recorded in the RAM information. First, according to the voltages taken from SKT U $\genfrac{}{}{0ex}{}{\text{j}}{\text{one}}$ and U $\genfrac{}{}{0ex}{}{\text{j}}{}$$\genfrac{}{}{0ex}{}{}{\text{2}}$ , the angle ψ _{j is} calculated and is also written to RAM. Next, the algorithm of the initial exhibition begins to execute in accordance with paragraphs 1.1-1.5 above. After calculating the azimuthal angle α _x1 at the time the exhibition mode starts, the calculator switches to other subprograms that ensure the gyroinclinometer to work (for example, “drift calibration”). When explaining the operation of the gyroinclinometer, we proceed immediately to the dynamic standby routine, which characterizes the completion of the exhibition mode. After the command to enter the SP into the motion mode, the last measurement of the angle ψ = ψ _in takes place, the azimuth of the sensitivity axes of the acceleration meters is calculated by formula (4), and according to expression (8), the increment elements of the orientation matrix ΔB ¹ at the initial step of the orientation algorithm.

 2. Determination of the azimuth and zenith angle of the well during movement of the downhole tool in the well.

Upon transition to the motion mode of the joint venture, the gyroscopic stabilization indicator loop and the angular velocity measurement loop, which in this case acts as the electrical arresting loop, continue to operate in the GS. To determine the azimuth and zenith angle in real time, the signals of the acceleration meters 13 and 14 (respectively, the voltages U ₃ = K ₃ a _xa , U ₄ = K ₄ a _za , where K ₃ , K ₄ are transmission coefficients) are measured, which are transmitted through the CCB (outputs 2 and 3) in a serial code are sent to a ground computer. In accordance with the operation of the orientation algorithm in the ground computer, the following actions are sequentially performed:
calculation of a part of the elements of the orientation matrix at the current step (9), (10);
calculation of the orientation angles θ _x , θ _y , θ _z at the current step (11);
calculating the increment of the orientation matrix in the current step 12;
the calculation of the orientation matrix in the current step 7, where the increment of the orientation matrix at the time of the start of movement is taken from the algorithm of the exhibition 8;
azimuth and zenith angle calculation in the current step 6.

During the operation of the joint venture, the temperature inside the joint venture is controlled. Why the temperature sensor 8 is connected to one of the inputs of the BTS and its voltage U ₆ = K ₆ T, where K _{6 is} the transfer coefficient; T temperature, after conversion to a parallel code in the form of a serial code, it is transmitted to a ground computer, which, when the maximum permissible temperature is exceeded, gives a corresponding message to the operator. At the same time, when the joint venture moves in the ground computer, the angle ψ, angle sensor 10, is recorded, which is not used in the algorithms of this mode, but can be of practical value, since it represents the joint rotation angle relative to the well axis.

 3. Description of the digital processing unit.

BCO communicates the GS SP with the ground computer and solves the following tasks:
the conversion of voltages U _m , m = 1-6 into a parallel code, which is formed by sequentially connected two-channel frequency converters 29, 30, 31 and reversible counters 32, 33, 34;
converting parallel code to serial code;
transmission and reception of a serial code between the microcomputer 1 and the ground computer:
organization of the exchange between the joint venture and the ground computer in accordance with the RS-232 type exchange protocol via a serial input / output channel.

The base of the central control center is the K1816 BE51 microcomputer, in which four eight-bit bidirectional ports P0-P3 are programmed as follows:
ports P0 and P2 are programmed to receive information in the form of a parallel code and are connected to the data bus (BD);
port P1 organizes the recording of information and the interrogation of reversible counters, while the digits from P1.0 through P1.5 are connected to the address bus (ША), and each bit corresponds to one address and is connected to the inputs of CE sampling permission and RD read permission of the corresponding reverse counters; bit P1.6 is programmatically configured to issue a synchronization command (CSX) and is connected to the polling inputs F of all counters 32, 33, 34; bit P1.7 is programmatically configured to output the clock frequency (PM) and connected to the SYN synchronization inputs of all the IFs 29, 30, 31 and all counters 32, 33, 34;
port P3 is programmed to issue a one-time command and organize exchange, while bit P3.0 is programmed to issue a command “turn on the turn of the platform of the platform”, and through bits P3.1 and P3.2 the input / output of a serial code is organized.

Consider in more detail the solution of these problems in accordance with the electrical circuit of figure 4. Since the conversion of voltages U _m into code is carried out simultaneously on all six channels, we consider the operation of one of the channels, for example, the channel of the acceleration meter a _x (voltage U ₃ ). The voltage U _{3 is} supplied continuously to the input IN _{1 of the} first channel of the IFF 30, the input of the SYN of which receives the clock frequency of the microcomputer 27. At the output of the IFF a sequence of pulses of the same duration is generated, the frequency of which is proportional to the value of the input signal, and if U ₃ > 0, then the pulses follow from the output + F ₁ , if U ₃ <0, then from the output -F ₁ . At the same time, a signal is set on the “+/-” control line that either sums or subtracts the pulses coming from the IF 30 on the reverse counter 33. As a result of summing (subtracting) the pulses, the counter 33 actually performs the operation of integrating the input signal U ₃ . Therefore, to obtain information about the code corresponding to the voltage U ₃ , the program must provide for the operation of scaling the code of the reverse counters, which consists in dividing the counter code by the signal accumulation time (conversion time). A further explanation of the operation of the BCC unit is in particular the organization of the exchange. When the power is turned on, a single-chip microcomputer is initialized (a reset pulse is formed through capacitor C), i.e. the corresponding program starts, which resets the corresponding registers, resets the RAM memory cells to zero, programming the ports and control registers, etc.

 The first byte of the command of the ground computer (command format: the first byte of the device address, the second byte of the command code) through the transceiver 28 and the high-speed serial port (bits of the port P3.1 and P3.2) is received and recorded in the corresponding register of the microcomputer 27. In this case interruption occurs and its processing begins. If the device address does not match the address recorded in the corresponding memory location of the ROM of the microcomputer 27, then the interrupt processing ends and the microcomputer 27 returns to its original state. If the command code does not match the code used in the central control center or the address or command is received with a parity error, then the microcomputer generates a response word (OS) (OS format) (the first byte of the device address, the second byte of the status byte), where it indicates the corresponding code in the status byte that a command is not on my list, either my address with a parity error is received, or a command with a parity error is received, and it ends the interrupt processing. Otherwise, the microcomputer 27 proceeds to execute the command transmitted by the ground computer, and also forms the OS, where the status byte indicates the absence of exchange errors.

To ensure the operation of the central control unit, four control commands are necessary, namely:
command to set the initial state;
synchronization command;
platform management team;
exchange team.

If the command code “Set initial state” is accepted, then the microcomputer 27 starts the initialization program again, if the command “Platform control” is accepted, then the microcomputer 27 sets the P3 port to the category P3.0 either logical zero or logical unit. In this case, in accordance with FIG. 2, a signal U _{k is} supplied _to the control input of the reference current master 17, which through its signal output using a torque sensor 22 will create a precession to the gyroscope around the axis OY _g . The indicator stabilization circuit repeats the movement of the gyroscope and platform 9 will also rotate at a given speed. If U _k will be logical zero, then the setter 17 will disconnect from the torque sensor 22 and the controlled movement of the platform 9 will stop. If the “Synchronization” command code is accepted, then the microcomputer 27 generates a pulse at the output of the discharge P1.6 of the port P1, which, upon entering the polling inputs F of the reverse counters 32, 33, 34, writes the contents of the counters 32, 33, 34 to the output buffer registers of the counters and then resets these counters.

 If the "Exchange" command code is accepted, then the microcomputer 27 along with the OS transfer proceeds to form a data packet, which occurs as follows: on bits P1.0-P1.5 of port P1 (connected to the meters counterparts), a code is formed that allows serial connection to ports Р0, Р2 through the bus of the buffer registers of the corresponding channels of the counters 32, 33, 34, and the microcomputer 27 reads the information from the registers, writes it to RAM, and alternately generates the corresponding data to the input / output of the transceiver 28 in the form of a serial code. The packet format is as follows: device address, status byte; the low byte of the first channel of the counter 32, the high byte of the first channel of the counter 32; the low byte of the second channel of the counter 32, the high byte of the second channel of the counter 32, etc. to the high byte of the second channel of the counter 34. Information from the transceiver 28 via the logging cable 2 (Fig. 2) enters the ground computer 3 of the type PC-486 Note Book on the RS-232 port, using the same transceiver that and in SP 1 in the CCU block 6. The only difference is that standard buffers are used to match the RS-232 levels.

 Based on the proposed method, a gyroscopic inclinometer was developed in the Aras MIP Arzamas. In addition to the brands of the individual components of the downhole tool specified in the list of elements in the drawings, the following technical specifications are given below.

Gyro stabilizer specifications
1. The gyrostabilizer operates from a DC power source with a voltage of (27 ± 2.7) V.

2. The current consumed by the gyrostabilizer does not exceed:
2.5 A from a DC source with a voltage of 27 V for 10 s, not more than 2 A at other times;
3. The readiness of the gyrostabilizer is not more than 2 minutes

4. The stability of the drift in one start of the gyrostabilizer is not more than 0.5 ^o / h.

5. The dynamic stabilization error under the action of sinusoidal oscillations does not exceed:
1.5 angle min relative to the axis Y _p ;
6. The gyrostabilizer provides load control relative to the axis Y _p :
± 40 ^o / s for a time t <10 s;
± 10 ^o / s for a time t <300 s;
± 4 ^o / s for a time t <2 hours

7. At a control speed of ± 40 ^o / s, the control current is (280 ± 80) mA. The dependence of the control speed on the control current is quadratic.

 8. The working angles of the gyrostabilizer pumping along the stabilization axis are not limited.

 9. Dimensions of the gyrostabilizer ⌀ 56 mm, L 500 mm.

 10. The mass of the gyrostabilizer is not more than 2 kg.

Downhole Tool Characteristics
Range of measurement of zenith angles, hail To 70
Range of measurement of azimuths, degrees 0-360
Definition error in continuous mode:
Zenith angles, hail 0.15
Azimutov, city 1
Depth, m 0.1
Maximum speed of measurement, m / h 5000
Maximum temperature, ^o C 100
Maximum pressure, MPa 80
Sizes of the downhole tool, mm:
Length 2500
Diameter 73
Weight, kg 20
The downhole tool is connected to the ground computer by a three-wire logging cable in a metal braid, and the braid and one core are used to supply power supply, and the other two wires are information.

 Prototypes of gyroscopic inclinometers were tested to determine the orientation parameters of oil wells with positive results in Tatneftegeofiziki of Bugulma, Tomskneftegeofiziki of Strizhevoy, Tomsk Region and Priobneftegeofiziki of Negan, Tyumen Region.

Claims (5)

1. The method of determining the azimuth and zenith angle of the well by means of a gyroscopic inclinometer, including measuring the acceleration of gravity along two mutually perpendicular axes, measuring the angular velocity relative to one of the above axes using a three-degree gyroscope, determining the initial orientation of the sensitivity axes of acceleration meters in azimuth, calculating the azimuth and zenith angle of the well, characterized in that the sensitivity axis of the acceleration meters and the sensitivity axis of the angular velocity meter the axes stabilize relative to the axis coinciding with the longitudinal axis of the downhole tool, at each step of the calculator when the downhole tool is moving in the well, the azimuth and zenith angle of the well are determined, for example, by the formulas

where i + 1 is the current step of the calculator;
b $\genfrac{}{}{0ex}{}{\text{i + 1}}{\text{lq}}$ , l, q ∈ [1,3] - elements of the orientation matrix B ^{i + 1} , which is formed as a product of matrices
B ^{i + 1} = ΔB ^{i + 1} • B ⁱ ,
where B ⁱ , B ^{i + 1} orientation matrixes at the previous and current steps of the calculator;

the increment of the orientation matrix, the elements of which are determined depending on the orientation angles Q _x , Q _y , Q _z according to the formulas

where ω $\genfrac{}{}{0ex}{}{\text{up}}{\text{dr}}$ - the angular velocity of the drift axes of sensitivity of the accelerometers and angular velocity relative to the stabilization axis;
Ω $\genfrac{}{}{0ex}{}{\text{i}}{\text{up}}$ - projection of the angular velocity of the Earth's rotation on the axis of stabilization;

elements of the orientation matrix formed by measuring projections a $\genfrac{}{}{0ex}{}{\text{i + 1}}{\text{x}}$ , a $\genfrac{}{}{0ex}{}{\text{i + 1}}{\text{z}}$ acceleration of gravity g;
τ is the sampling period of the calculator, and the initial value of the orientation matrix is

where α _xв - azimuthal angle of the axes of sensitivity of the acceleration meters at the end of the exhibition. 2. The method according to claim 1, characterized in that to determine the azimuthal angle of the axes of sensitivity of the acceleration meters at the time of the end of the exhibition, these axes are rotated around the stabilization axis at a constant speed by a predetermined angle, the rotation angle of these axes relative to the body, the horizontal component is measured in successive positions Ω _{zg of the} angular velocity of rotation of the Earth, together with the angular velocity of the drift of the gyroscope relative to the axis, which is the sensitivity axis of the angular velocity meter, according to the measurement results calculate the average angular velocity of rotation of the platform ω _{in the} systematic component of the drift of the gyroscope ω $\genfrac{}{}{0ex}{}{\text{c}}{\text{dr}}$ and form a reference model of the measured angular velocity
ω _ej = ω $\genfrac{}{}{0ex}{}{\text{c}}{\text{dr}}$ + Ω _sg sin (ω _in • j + Φ _x ),
where j is the measurement number;
Φ _x is the phase shift,
and to estimate the phase shift, a residual function is calculated representing the sum of the squares of the difference of the reference ω _ej and the measured ω _j angular velocities over the entire set of measurements, which is minimized by the phase shift, and the azimuthal angle of the sensitivity axes of the acceleration meters at the time the exhibition ends is determined by the formula
α _xв = ψ _в - ψ ₁ + α _x1 ,
where ψ ₁ , ψ _in - the angle of rotation of the axes of sensitivity of the acceleration meters relative to the body of the downhole tool around the axis of stabilization at the moments of the beginning and end of the exhibition;
α _x1 is the azimuthal angle of the sensitivity axes of the acceleration meters at the beginning of the exhibition, which is equal to the phase shift Φ _x minimizing the residual function.  3. A gyroscopic inclinometer containing a downhole tool, equipped with an acceleration meter along two mutually perpendicular axes that are perpendicular to the longitudinal axis of the downhole tool, and an angular velocity meter relative to one of the two indicated axes, consisting of a three-stage gyroscope with angular sensors and sensors mounted on its suspension axes moments, and the first angle sensor on the measuring axis of the gyroscope is connected through an amplifier of the loop for measuring the angular velocity to the second torque sensor perpendicular which is connected to the axis angle sensor, a ground computer connected by a logging cable to the downhole tool, characterized in that the downhole tool contains a uniaxial gyro stabilizer, on the platform of which an accelerometer is rigidly mounted, with sensitivity axes oriented perpendicular to the gyro stabilizer stabilization axis, and a three-stage gyroscope, a second angle sensor which through the stabilization amplifier is connected to a mining engine kinematically connected with the stabilization axis, on which the output angle sensor is fixed made, for example, in the form of a sine-cosine transformer, and a digital processing unit, to the corresponding inputs of which are connected the outputs of the angle sensor of the hydraulic stabilizer, the outputs of the accelerometer and the output of the angular velocity meter, the first output of the digital processing unit being connected to the control input of the reference current master, the signal output of which is connected to the first gyroscope moment sensor located on an axis perpendicular to the stabilization axis, and the logging cable is connected with its second inputs to the second and third outputs of the digital processing unit.  4. The inclinometer according to claim 3, characterized in that the digital processing unit contains a single-chip microcomputer, a transceiver, three two-channel voltage-frequency converters and three two-channel reverse counters, the ports P0 and P2 of a single-chip microcomputer programmed for input, connected by their inputs to the corresponding outputs low and high bytes of the data bus of the reverse counters, port P1, programmed for output, with bits from P1.0 to P1.5 is connected respectively to the inputs of sampling permission and read permission corresponding reverse counters, bit P1.6 is connected to the polling inputs of all reverse counters, and bit P1.7 is connected to the synchronization inputs of all voltage and frequency converters, and the bit of port P3.0, programmed to issue a control command, is connected to the first output of the block digital processing, the inputs of the voltage-frequency converters are respectively the inputs of the digital processing unit, and the bits of the port P3.1 and P3.2 of a single-chip microcomputer programmed for serial input-output are connected through a transceiver with a logging cable and are the input-output of the downhole tool.  5. Inclinometer according to claims 3 and 4, characterized in that it contains a temperature sensor that signals the temperature in the downhole tool, the output of which is connected to one of the inputs of the digital processing unit.

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