Three-component downhole magnetometer based on high-temperature digital fluxgate

[0027] Next, the technical solutions in the embodiments of the present invention will be described in the following examples, and embodiments are merely described herein, not all of the embodiments of the present disclosure, not all of the embodiments of the present disclosure are intended. Based on the embodiments in the present application, those skilled in the art do not have all other embodiments obtained without creative labor, all of which are protected by the present application.

[0028] like Figure 1 to 5 As shown, the embodiment of the present invention provides a magnetometer medium-based on a three-component well based on a high-temperature digital magnetic gate, and a magnetometer based on a high-temperature digital magnetic gate-based three-component well is suitable for mineralization, specifically, The magnetometer in the three-component wells of high-temperature digital magnetic gate can be used for mineral exploration of mines with a well diameter of about 3,000 meters, ambient temperature of about 155 ° C. The magnetic gauge is a long strip according to a three-component well-based well, a diameter of 20 mm to 500 mm (e.g., 50 mm), with a total length of 800 mm to 10,000 mm (e.g., 1546 mm), suitable for space under the mine. The magnetometer based on the high-temperature digital magnetic gate-based three-component well includes a three-axis magnetic gear door sensor 105, a magnetic communication gate signal processing circuit 106, a three-component quartz acceleration meter 107, a power supply circuit 108, a connector 109, a closed carrier tank The housing 101 is supported by the skeleton 103 and the buffer 104.

[0029] Since the magnetometer is small in a three-component well-based well (in the range of 20 mm to 500 mm), the magnetometer based on the high-temperature digital magnetic gate-based three-component wells can accommodate most mines. And in depth into the mine to measure the magnetic field measurement, it can obtain the effect of magnetic field measurement than the effect of the ground magnetic field measurement (whose magnetic field measurement in the well can reach the space measurement of closer geology, there is abnormal place to be better Reflected).

[0030] The closed pressure compartment housing 101 is the outermost layer member of the magnetometer based on the three-component well of the high-temperature digital magnetic gate, the sealed compression compartment housing 101 having a housing chamber. The three-axis magnetic gear gate sensor 105, the magnetic gate signal processing circuit 106, the three component quartz accelerometer 107, the power supply circuit 108, the support frame 103 and the buffer 104 are all set to the sealed Inside the compression compartment housing 101, at least a portion of the connector 109 is disposed in the housing chamber of the closed pressure compulsive compartment housing 101.

[0031] The sealed carrier compartment housing 101 is for processing the components (e.g., the three-axis magnetic gear door sensor 105, the magnetic gate signal) of the magnetometer based on the high-temperature digital magnetic gate. Circuit 106, the three component quartz accelerometers 107, the power supply circuit 108, the connecting member 109) Perform protection and support so that the components inside the magnetometer in the three-component wells based on the high-temperature digital magnetic gate Affected by physical impact, and to prevent the components of the magnetometer within the three-component wells based on high-temperature digital magnetic gate, the components of the magnetic gauges are moist, high temperature, high pressure, etc., can not function properly.

[0032] It is proven, since the triaxial magnetic door sensor 105, the magnetic gate signal processing circuit 106, the three component quartz acceleration meter 107, the power supply circuit 108, the support skeleton 103 and the buffer 104 all set Within the closed pressure compartment housing 101, the magnetometer is operated at a high temperature environment of about 155 ° C in the mine in a high temperature environment of about 155 ° C in the mine, and the magnetometer is based on the high temperature environment of about 20,000 hours. The components within the three-component wells in digital magnetic gate can still operate normally, that is, the magnetic gauges in the three-component well-based well based on the high-temperature digital magnetic gate can operate in a high temperature mine environment.

[0033] The sealed compression compartment housing 101 is made of a non-magnetic material and a material resistant to high temperature and high pressure. On the one hand, it can prevent its own magnetic force from affecting the operation of the magnetic meter itself based on the high-temperature digital magnetic gate. On the other hand, it can avoid the effect of higher external environments to affect the operation of each component in the closed pressure compulsive compartment housing 101.

[0034] The closed pressure compartment housing 101 is a long strip having a ring card buckle 102, which is used to physically connect with other devices.

[0035] The three-axis flux door sensor 105, the magnetic gate signal processing circuit 106, the three component quartz accelerometer 107, the power supply circuit 108 and the buffer 104 are all set to (fixed to) the support Skeleton 103. The buffer 104 is disposed at a position of the first end of the support frame 103. The connector 109 is disposed at a position of the second end of the support frame 103. The power supply circuit 108, the three component quartz acceleration meter 107, the three-axis magnetic gear door sensor 105, the magnetic gate signal processing circuit 106, is disposed in the first end and the above-described first end and the above Between the second end, and the power supply circuit 108 is disposed at a position adjacent to the support frame 103, the three-axis magnetic communication door sensor 105 is disposed in the support skeleton 103's buffer 104 The position between the second end of the support skeleton 103 is adjacent to the buffer 104, ie, the three-axis magnetic gear sensor 105 and the magnetometer based on the high-temperature digital magnetic gate. The bottom end (the first end) is separated by the buffer 104, the buffer 104 plays a buffer when the mine based on the magnetic instrument based on the high-temperature digital magnetic gate, can withstand voltage and shockproof. , Sealed waterproof, facilitates the protection of the high-temperature digital magnetic gate-based wales in the magnetic instrument-based mine measurement in the magnetic instrument-based mine measurement based on high-temperature digital magnetic gate. Specifically, the buffer 104 is configured to avoid a physical impact on the triaxial magnetic communication door sensor 105, the magnetic gate signal processing circuit 106, the three component quartz accelerometer 107, the power supply circuit 108 caused by Damage, in addition, the buffer 104 also has the effect of isolating magnetic interference.

[0036] The magnetic gate signal processing circuit 106 is disposed in the support skeleton 103 located between the three-axis magnetic gear door sensor 105 and the second end of the support frame 103, the three-component quartz accelerometer 107 The position disposed in the support skeleton 103 is located between the magnetic gate signal processing circuit 106 and the second end of the support frame 103.

[0037] The three-axis flux door sensor 105 is electrically connected to the power supply circuit 108, the magnetic gate signal processing circuit 106, the three component quartz acceleration meter 107 and the power supply circuit 108, the magnetic gate signal processing The circuit 106 is electrically connected, the power supply circuit 108 is electrically connected to the magnetic gate signal processing circuit 106, and the connecting member 109 is electrically connected to the power supply circuit 108, the magnetic gate signal processing circuit 106.

[0038] The three-axis magnetic gear door sensor 105 is an apparatus for measuring a magnetic field based on a Faraday electromagnetic induction principle. The three-axis magnetic gear door sensor 105 can convert the spatial magnetic vector that cannot be directly measured into electrical signals that can be measured, and can then reverse the corresponding magnetic field strength of the magnetic signal by measuring the size of the voltage signal.

[0039] In the embodiment of the present invention, the X, Y, Z three-axis coordinate system of the three-axis magnetic gear door sensor 105 coordinate with the X, Y, Z three-axis coordinate system of the three-component quartz accelerometer 107, which makes it possible to make The error is minimal.

[0040] The three-axis flux door sensor 105 is used to measure the magnetic field strength of the magnetic material outside the magnetic material outside the three-component well-based three-component wells, and outputs a magnetic field measurement as analog signal. The analog signal output from the three-axis magnetic gear door sensor 105 and the analog signal output from the three-component quartz acceleration meter 107 inputs to the 24bit eight-channel high-speed analog-to-digital converter ADC of the magnetic gate signal processing circuit 106. Convert to digital signals.

[0041] The three-shaft magnetic gear door sensor 105 of the magnetometer based on the high-temperature digital magnetic gate-based three-component well includes three orthogonal magnetic enhancing elements, measuring the distribution law of mineral magnetic abnormalities in three directions, so that the mine can be obtained. The longitudinal depth of the body and the inner mineral in a section are located in the direction of the drilling, and therefore, the ore body can be positioned only on the data of the single oriented well. The three-axis magnetic gear sensor 105 can simultaneously measure the three mutually perpendicular positive components of the magnetic field: ΔZ, ΔX, and ΔO, the three-axis magnetic communication door sensor 105 can measure the size of the magnetic field, also Can determine the direction of the magnetic field.

[0042] The measurement method of the three-axis magnetic door sensor 105 includes continuous measurement and point measurement (maximum frequency 1 times / 1 second), and the continuous measurement can identify magnetic substances having a thickness of not less than 0.5m, and the point measurement can recognize the thickness of not less than 5m. Magnetic substance. The three-axis magnetic door sensor 105 employs a flux measuring mode, and the magnetic field strength measurement in the well is continuously measured and the point measurement, and the continuous measurement speed must not exceed 15 m / min, and there is no more than 10 m / min in an abnormal segment.

[0043] The three-axis magnetic gear door sensor 105 employs a three-axis magnetic transfer door orthogonal structure, and the magnetic communication of each shaft employs a parallel differential structure of a dual magnetic core, and the magnetic core is selected by thin highly magnetic permeability, low coercivity. The low-magnetic slope is processed, and the magnetic pass door of each shaft also includes an excitation coil, the excitation coil, to insert it into a low temperature coefficient of 轱轱 magnetic The mandrel (which material can be, for example, a ceramic or glass material), and induces the induction coil (detection coil), the induction coil can be shared with the feedback coil, of course, the feedback coil and the detection coil also Can be shared.

[0044] By removing the redundant structure, the low temperature coefficients of polyester materials are finely processed micro-magnetic pneumatoid probe skeletons, especially the processing error of orthogonal mounting holes, which is advantageous for the three-axis magnetic flux door to obtain optimum regularities.

[0045] The above three-axis magnetic door sensor 105 reduces the use of analog devices, and the circuit design is optimized, low cost, and provides higher precision.

[0046] The magnetic gate signal processing circuit 106 is configured to perform a sensitive detection wave, integrating digital signal (specifically, the phase sensitive detection module in the magnetic gate signal processing circuit 106 pair received The digital signal performs a sensitive detection wave, and the integral module in the magnetic gate signal processing circuit 106 processes the digital signal after the sensitivity detection. The voltage digital signal corresponding to the magnetic field value is obtained as a closed loop control. Cache the digital signal. After completing the digital signal storage, by i 2 The C interface reads the data of the onboard temperature sensor. After the correction, the data is uploaded to the user end through the CAN bus. Onboard temperature sensors are used to get ambient temperature information in real time.

[0047] When debugging, data can also be obtained through the serial port preserved by the magnet gate signal processing circuit 106.

[0048] The three component quartz accelerometers 107 are used to acquire acceleration data to direct the triaxial magnetic communication door sensor 105 and acquire angle information. The three-component quartz accelerometer 107 includes a KT-JB6 series quartz flexible accelerometer. The KT-JB6 series quartz flexible accelerometer is an existing accelerometer on the market, which is a miniaturized, high temperature resistant seismic accelerometer. This product has excellent repetitiveness, start-up performance, high temperature resistance and high reliability, etc., in line with design demand.

[0049] The power supply circuit 108 is configured to convert an AC voltage input through the connector 109 into a DC voltage, the power supply circuit 108 being the three-shaft magnetic gear sensor of the magnetometer based on the three-component well-based well-based three-component well. 105, the magnetic gate signal processing circuit 106, the three component quartz acceleration meter 107 provides the desired power source, in particular, the power supply circuit 108 is an AC-DC power supply circuit, the power supply circuit 108, by which is based on a high temperature. The connector 109 of the magnetic end portion of the magnetic gate of the digital magnetic gate is connected to the external 220V power source, the power supply circuit 108 for converting the external 220V power source to a voltage of ± 15V, +7V, + 5V to give the magnetic The gate signal processing circuit 106, the three component quartz accelerometer 107, etc., etc. The power supply circuit 108 uses the FH18 series multi-channel isolation to output high temperature AC-DC power supply circuit 108, and the specific model is MH18-150D15-S7-S5. The power supply circuit 108 is configured to have high temperature, impact resistance, and moisture resistance. The operating temperature of the power supply circuit 108 is -55 ° C to + 175 ° C, and the outer casing can be resistant to + 185 ° C, which conforms to the design requirements.

[0050] The connecting member 109 is connected to the power supply circuit 108 and the communication cable (CAN bus) of the magnetometer externally in the three-minute well-based three-component well of the high-temperature digital magnetic gate, and is used to transmit measurement information to the host computer (the user of the ground) End) and receive control signals from the host machine.

[0051] The magnetic gate signal processing circuit 106 is configured to enlarge the signal sensed by the triaxial magnetic door sensor 105 and digitized the amplified signal to obtain a digital signal of the voltage analog signal corresponding to the magnetic field value. The digitally treated signal is subjected to phase-sensitive rectification, temperature correction processing, and the error correction processing of the acceleration data collected by the temperature correction process and the three-component quartz accelerometer 107.

[0052] The magnetic gate signal processing circuit 106 includes a control circuit, an excitation circuit, a feedback circuit, an analog-to-digital conversion circuit. The control circuit is electrically connected to the excitation circuit, the feedback circuit, the analog to digital conversion circuit. The excitation circuit is electrically connected to the excitation coil of the triaxial magnetic gear sensor 105. The feedback circuit is electrically connected to the feedback coil of the triaxial magnetic gear sensor 105. The analog-to-digital conversion circuit is electrically connected to the induction coil of the triaxial magnetic communication door sensor 105.

[0053] The control circuit can be any of the FPGA, DSP, or the control circuit is a combination of FPGA and ARM chip. Next, the control circuit is FPGA as an example. The FPGA uses Xilinx's Zynq7000 Series Industrial-grade chip XC7Z020CLG400i, which is programmable by a conventional FPGA chip (referred to as, PL) and one Cortex TM-A9 Application Level Processor (Abbreviation, PS) Composition, the PL end of the FPGA can be used as a parallel operation of conventional FPGA, programmable hardware circuit and hardware acceleration function, the FPGA can be flexibly implemented by its PS Operation and serial communication function. Pre-processing (such as phase sensitive detection, digital filtering, etc.) and digital closed-loop feedback links (such as PID, delta-σ modulation, PWM modulation, etc.) are implemented in the PL end of the FPGA, such as data correction, CAN and The operation of serial port communication is implemented in the PS end of the FPGA. Further, the PS end of the FPGA is also used to process the ambient temperature information acquired by the onboard temperature sensor.

[0054] The data acquired by the analog-to-digital conversion circuit ADC is processed by the EMIO interface into the PL end of the FPGA. The data after the pre-processing is partially connected to the digital closed-loop feedback link, served as closed loop control, part of the FPGA The AXI interface is cached to the PS side and is transferred to the ground to the ground after being corrected.

[0055] The excitation circuit includes an excitation signal square wave generating module, a power amplifying module. The excitation circuit is used to generate a stable excitation frequency source (excitation signal) to provide a exciting signal, specifically, the excitation circuit to the three-axis magnetic communication gate sensor 105. After the coil provides the excitation signal, the excitation coil of the three-axis magnetic door sensor 105 produces a periodically changed magnetic field, and the magnetic core of the three-axis magnetic communication door sensor 105 periodically in the saturation state and the unsaturated state. alternately. The FPGA includes an excitation signal generating module for generating a bipolar square wave signal, the excitation circuit drives the excitation coil according to the bipolar square wave signal, in order to improve the excitation signal. Drive capability, the excitation signal generating module or the excitation circuit comprises a MOS tube power amplifier of a primary push-pull structure, and the power amplifier chip is Si4532DY.

[0056] Since the induced signal generated by the three-axis magnetic flux door sensor 105 is relatively weak, the analog-to-digital conversion circuit pair is received after the analog to digital conversion circuit of the magnetic gate signal processing circuit 106 receives the induction signal. The induction signal is conditioned, and then the digitization process is performed (the induction signal exhibiting as analog signal is converted into a digital signal). After the detection module of the analog-to-digital conversion circuit detects the induction signal (the sensing signal of the three-axis magnetic gear sensor 105x, Y, Z three axis), the induction signal passes through the front end low pass filter module, and then passes through the rear end The first-order reverse input low-pass filter module is enlarged, and the filter is performed, and the rectification is performed to reduce the mixing of the induction signal, so that the induction signal passed through the above treatment satisfies the range and the scope of the target sampling rate. The input range of the analog-to-digital converter ADC of the analog-to-digital conversion circuit is input to the modulus converter ADC. Among them, an amplifier for amplifying the induction signal is a high-temperature amplifying chip OPA 211 of Texas Instrument (Ti), with a working temperature of -55 to 210 ° C.

[0057] The feedback circuit is mainly composed of a filter module and a voltage current conversion module. The feedback circuit is primarily converted to a DC current signal generated by the FPGA, and outputs a feedback coil of the triaxial magnetic gear sensor 105 to drive the feedback coil. Wherein the filter module is a first-order RC filter, the filter module is configured to convert the PWM signal low through the FPGA to the corresponding DC voltage signal. The voltage current conversion module includes an operational amplifier, a capacitor, and a resistor, the capacitor constitutes an integrating circuit, the integration circuit, which can make the filtered signal more stable, and the inductance of the feedback coil changes When the current does not transient, and the voltage across the capacitor does not transient, thereby causing the feedback current to stabilize.

[0058] The PWM modulation module of the FPGA is configured to perform digital PWM modulation based on the signal output by the digital filter module, and the signal of the Δ-δ modulation module, to perform the number of pulsed wave signals of different duty cycle. To the corresponding DC signal (ie, generate a pulse width modulation square wave signal), it is equivalent to a digital-to-analog converter DAC, which can not only reach the feedback effect, but also save a digital converter to achieve a saving device. The purpose of miniaturization circuit.

[0059] Considering the number of single-channel sampling positions required by the magnetometer required in the three-component well-based well based on the high-temperature digital magnetic gate, 6 channel data synchronous acquisition (three-channel magnetic communication gate data, three-channel accelerometer data), The analog-to-digital conversion circuit uses the high-precision 8-channel 24-bit synchronous sampling AD chip AD7768, a high-precision 8-channel 24-bit synchronous sample. The maximum ADC output data rate of each channel of the chip is 256KSPS, and each channel is independent of each other, and different channels can be set different sampling rates.

[0060] The magnetometer is also provided with a heat insulating housing in the three-component well-based well-based three-component well, and the closed pressure compartment housing 101 is also provided with a heat insulating housing, the three-axis magnetic gear door sensor 105, The magnetic gate signal processing circuit 106, the three component quartz accelerometer 107, and at least one of the power supply circuit 108 is disposed within the insulation housing, in particular, in the magnetic gate signal processing circuit 106 Each device, module, etc. are all provided in the insulation housing such that the main chip in the magnetic gate signal processing circuit 106 can not be affected by the high temperature environment. The insulating housing is fixed to the support skeleton 103, and the outer surface of the insulation housing has a gap with the inner surface of the closed pressure compulsive compartment housing 101, i.e., the insulation housing. The outer surface is not connected to the sealed compression compartment housing 101, and therefore, the magnetic gate signal processing circuit is applied under a dual heat insulation of the insulating housing and the sealed compression compartment housing 101. 106 can be protected from the higher temperature interference and impact in the mine, facilitating ensuring that the components, modules within the magnetic gate signal processing circuit 106 operate normally. It is pronounced, in the case where the magnetometer is at a high temperature environment of about 200 ° C in a high temperature environment of about 200 ° C, the temperature inside the insulation housing can be kept at 50 ° C in a high temperature environment based on high-temperature digital magnetic gate. The Zynq7000 series of FPGAs provided below the company's highest operating temperature of 100 ° C can be effectively ensured that the FPGA is operating normally.

[0061] The FPGA also includes a phase sensitive rectification module, a digital filter module, a temperature correction module, an error correction module, a proportional-integral-differential control module, a pulse width modulation module, and the like. The phase sensitive rectifying module is configured to perform the pre-processing of the modulus-by-side signal for the pre-processing, and the digital filter module is used to perform signals that pass through the phase sensitive rectification. Conduct low pass filtering.

[0062] The working environment of the magnetometer based on the three-minute well-based well of the high-temperature digital magnetic gate is a high temperature environment, and the proportional coefficient of the three-axis magnetic door sensor 105, the zero-navigation and orthogonality three parameters are in different temperatures. Non-linear changes, therefore need to be analyzed by test calibration and regression analysis, and fitting three parameters in full temperature range, thereby effectively narrowing the measurement error caused by these parameter changes. Considering the matrix Verilog code is complicated, the code is performed by the PS terminal of the FPGA.

[0063] The temperature correction module is used to correct the measurement error of the three-axis magnetic gear sensor 105 caused by temperature changes, and the specific correction mode is:

[0064] Assuming that the magnetic field strength measurement value is x, y, z in the coordinate axis of the ideal orthogonal triaxial magnetic door sensor is X, Y, Z, and in the non-orthogonal triax magnetic door sensor (actual three-axis magnetic flux The component of each coordinate axis is x ', y', z 'in the coordinate system of the door sensor. The conversion relationship thereof can be expressed as the z-axis of the three-axis magnetic gear sensor 105.

[0065] H '= pH + b (1)

[0066] Among them, h = [x y z] T , H '= [x' y 'Z'] T , B = [bx by bz], P is the conversion matrix, Kx, Ky, Kz represents the scale factor, α, β, γ of each coordinate axis, represents the non-correct angle between the respective coordinate axes, BX, BY, BZ is the three-axis magnetic communication door sensor 105 The zero point error of each coordinate axis.

[0067] when At the time, the error value of KX, KY, KZ, α, β, γ, bx, by, and bz can be obtained, and the error value of different errors can be obtained in different errors.

[0068] The proportional coefficient of the magnetic door changes with the change of the temperature, and the temperature has a non-linear change with the temperature, according to the measured value of the magnetic door, the corrected magnetic field true value can be obtained. It should be:

[0069] H = P -1 (H'-b) (2)

[0070] Where P -1 For P's inverse matrix, it can be expressed as:

[0071] The gesture steering correction to the magnetic doors is to solve P -1 , Each parameter in the B matrix. By rotating the magnetic gate, rotating the magnetic gate, and by the fitting method of the ellipsoid, it is possible to obtain parameters such as the proportional coefficient, non-orthogonality, and zerofide.

[0072] The PP measured at a temperature -1 The correction matrix can be expressed as: p -1 i The zero firing matrix can be represented as: B i The correction matrix measured by multiple temperature points is:

[0073]

[0074] The zerofide correction matrix is ​​similar to this.

[0075] The proportional coefficient SX obtained at different temperatures according to the magnetic flux door X axis 1 SX 2 SX 3... Use the four-order polynomial fitting method to fit the X-axis proportional factor with a curve with temperature changes:

[0076] SX (t) = k 4 * T 4 + K 3 * T 3 + K 2 * T 2 + K 1 * T 1 + K 0.

[0077] The same method can get the proportional coefficient of Y, Z axis and the zero firing of the temperature change:

[0078] SY (T), SZ (T), θ (T), ε (t), η (t), bx (t), by (t), bz (t).

[0079] When the correction is based on the measured temperature value:

[0080] SX (t) = k 4 * T 4 + K 3 * T 3 + K 2 * T 2 + K 1 * T 1 + K 0.

[0081]That is, it is possible to obtain the proportional coefficients K0, K1, K2, K3, K4 of the X axis at the current temperature, and at the same time, the temperature value is substituted to other calibration curves:

[0082] SY (T), SZ (T), θ (T), ε (t), η (t), bx (t), by (t), bz (t),

[0083] Gets the correction value of other parameters at this temperature, and then according to the correction formula:

[0084] H = P -1 (H'-b),

[0085] The real value of the measured magnetic field strength at the current temperature can be calculated.

[0086] This function can be developed and implemented using the Vivado software to develop and implement this function in the temperature calibration module within the FPGA chip. The corresponding temperature calibration program (file) is stored in the temperature correction module.

[0087] When the magnetometer is in a running state in the three-component well based on the high-temperature digital magnetic gate, the temperature correction module is configured to receive the temperature value sensed by the magnetometer based on the high-temperature digital magnetic gate, based on the above The formula, the coefficient, the measurement error of the triaxial magnetic door sensor 105 is corrected.

[0088] The FPGA further includes an error correction module for a coordinate system and / or the three-component quartz accelerometer 107 of the triaxial magnetic communication door sensor 105 based on the correction result of the temperature correction module. The error of the coordinate system conversion is corrected (corrected), the specific correction method is:

[0089] The ideal three-axis magnetic door sensor is measured for three-axis orthogonal vector, and the total field value of its output is independent of the measurement direction, and each measurement axis of the actual three-axis magnetic door sensor cannot be completely orthogonal, each The scale factor of the shaft, the zero point error is also incomplete, so the three-axis magnetic door sensor 105 generates a steering error during rotation.

[0090] In the same way, the ideal three-component quartz accelerometer is also orthogonal, but in fact, it is impossible to completely orthogonality between the three axes due to the limitations of the processing and installation process.

[0091] Ideally, the three-shaft magnetic gear door sensor 105 in the magnetic gauge based on the three-component wells of a high-temperature digital magnetic gate is completely coincident, and the coordinate system of the three component quartz accelerometer 107 is completely coincident. Value converts the magnetic field measurement data to the vertical component and the horizontal component.

[0092] However, when the actual measurement, the two coordinate systems of the magnetometer based on the high-temperature digital magnetic gate well cannot completely coincide, which will occur in the coordinate system conversion error. Therefore, the coordinate system conversion needs to be corrected (compensated).

[0093] The gravity value and magnetic field value can be accurately measured after error compensation, respectively, GX, Gy, Gz, BX, BY, BZ. The three-shaft magnetic door sensor 105 and the three-component quartz accelerometer 107 are not coincidentally shown (3):

[0094]

[0095] Among them, GGX, GGY, and GGZ are all modified magnetic field values, BX, BY, BZ are the magnetometer error correction, temperature correction of the magnetic gauge, the temperature correction, the triplex magnetic field value, K1 ~ K9 is the coordinate system correction factor.

[0096] Collect a series of gravity measurements by rotating Measurement with magnetic field In the correction software, the coordinate system correction factor can be obtained.

[0097] The coordinate system correction matrix coefficient can be applied by the least squares method, i.e., the minimum multiplier can solve the unknown coefficient, reach the coordinate system conversion error correction purpose.

[0098] The corresponding coordinate conversion error correction program (file) is stored in the error correction module.

[0099] When the magnetometer is in the operating state in the three-component well-based well-based well, the error correction module is used to pass the acceleration data collected by the three component quartz accelerometer 107 and passing according to the coordinate system correction coefficient. The magnetic field sensing value corrected by the temperature correction module performs coordinate system conversion error correction.

[0100] The FPGA also includes a regulator module, the regulator module, is a linear regulator chip, for example, a chip of the model LT3042, LT3045, and LT3090. The linear regulator chip can not only realize voltage conversion, while avoiding the lack of switching power supply ripples.

[0101] The linear regulator chip is used to convert ± 15V, + 7V, + 5V voltage of the power supply circuit 108 into ± 12V, + 5V, + 3.3V voltage required in the probe and circuit.

[0102] In the regulator circuit, after isolating the analog power supply and the digital power supply, the magnetic beads connect each common end to reducing the purpose of noise.

[0103] Since the above control circuit includes the temperature correction module and the error correction module, the temperature correction module is configured to achieve a temperature correction, and the error correction module is configured to implement coordinate system conversion error correction, and therefore, the embodiment of the present invention The magnetic gauges in the three-minute well-based well-based three-component wells can be directly corrected to the measured values ​​in real time, facilitate backend data processing and application.

[0104] Since the induced signal generated by the triaxial magnetic gear door sensor 105 is digitally processed, it is possible to prevent each circuit in the magnetic gauges in the three-component wells based on the high-temperature digital magnetic gate from being affected by the temperature, electromagnetic or the like. The accuracy of the measurement result of the analog signal is characterized, thereby effectively improving the sensing accuracy of the triaxial magnetic gear sensor 105.

[0105] In summary, although the present application has been disclosed in the preferred embodiment, the above preferred embodiments are not intended to limit the present application, and those skilled in the art can be used in the spirit and scope of the present application. Finishing and moistening, so the scope of protection of the present application is based on the scope of the claims.