Transient electromagnetic instrument detection unit and method

Abstract

The invention relates to the technical field of geophysical prospecting, in particular to a transient electromagnetic instrument detection unit and method, and the detection unit is powered by a detachable power supply nipple, is connected with a drill rod, and is pushed by the drill rod to measure in a drill hole. The detection unit comprises a shell and a detection framework, the detection framework comprises a detection support, a threaded nest, a detection control module, a transmitting antenna, a receiving antenna and an attitude measurement module, the receiving antenna is used for measuring three-component magnetic field change information, and the attitude measurement module is used for measuring working attitude information of the detection unit. The system has a high integration level, can realize integration of drilling track measurement and transient electromagnetic three-component measurement, can complete long drilling hole detection, does not need to be connected with a communication cable, and effectively reduces the system cost.

Description

Technical Field

[0001] The invention relates to the technical field of geophysical exploration, and in particular to a transient electromagnetic instrument detection unit and method. Background Art

[0002] Mine water damage is one of the main disasters in the production and construction of coal mines. The current mechanized and rapid tunneling of tunnels has continuously increased the demand and requirements for coal mine water prevention and control technology and equipment. Among the geophysical methods for mine water damage exploration, mine transient electromagnetic method is currently a commonly used geophysical method with good results in detecting hidden water-rich areas in coal mines. Its working principle is to inject pulse current into the transmitting loop. The high-speed change of current will generate a pulse magnetic field underground. The target body underground will be excited by the pulse magnetic field to generate induced eddy currents, thereby generating a secondary induced magnetic field. By using a magnetic field sensor to sense the change in magnetic field intensity, the electrical parameter information of the underground target body at different depths can be obtained. The mine transient electromagnetic method has the advantages of long detection distance and sensitive response to low-resistance bodies.

[0003] The transmitting and receiving coils of conventional mine transient electromagnetic methods generally use multi-turn square loops, which have problems such as large detection blind areas, susceptibility to interference from metal bodies in tunnels, large volume effects, and low detection accuracy. Compared with the above-mentioned geophysical detection methods, the borehole transient electromagnetic method places the receiving probe in the borehole. Since it is closer to the detection target and farther away from the tunnel, it can not only observe a stronger response signal, but also effectively weaken the interference of various electromagnetic signals outside the hole, which can meet the needs of deep burial and refined detection, and is especially suitable for water hazard detection.

[0004] At present, the working methods of observing transient electromagnetic field response in boreholes mainly include: ground-well transient electromagnetic method, tunnel-borehole transient electromagnetic method, transient electromagnetic logging and borehole transient electromagnetic method. Among them, the borehole transient electromagnetic instrument sets the transmitting coil and the receiving coil in the borehole at the same time, and uses the drill rod of the drilling rig to push it over a long distance. It is used with a drilling rig, pushing and exploring at the same time, and can be used as an important means of long borehole detection.

[0005] The drilling transient instrument in the prior art still has some shortcomings: since the detection unit is advanced in the borehole with the drill pipe, it is limited by the borehole size and integration level. The receiving antenna can only measure the magnetic field change information in one component direction at a time. To complete the measurement of the three-component electromagnetic signal, it is necessary to send transient pulses in the three component directions respectively and collect the magnetic field component signals in the corresponding directions. After denoising, inversion and imaging of the collected data, the overall induced magnetic field information of the target range is obtained; at the same time, the data collected by the electromagnetic instrument needs to be transmitted to the host computer in real time through a communication cable for storage. The transient electromagnetic instrument itself does not provide the function of storing data, which increases the complexity of the system connection and the system cost. Summary of the invention

[0006] The present invention provides a transient electromagnetic instrument detection unit with high integration, which can realize the integration of drilling trajectory measurement and transient electromagnetic three-component measurement. At the same time, the transient electromagnetic instrument has the function of storing test data for a long time, can complete long borehole detection without connecting communication cables, and effectively reduces system costs.

[0007] This application provides the following technical solutions:

[0008] A transient electromagnetic instrument detection unit is powered by a detachable power short section and connected to a drill pipe, comprising a shell and a detection skeleton, wherein the detection skeleton is installed in the shell, and the detection skeleton comprises a detection bracket, a threaded nest, a detection control module, a transmitting antenna, a receiving antenna and a posture measurement module, wherein the receiving antenna is used to measure three-component magnetic field change information, and the posture measurement module is used to measure the working posture information of the detection unit.

[0009] Technical principle: The detection unit and the power supply unit are designed to be separated, and the transmitting unit, the three-component antenna receiving unit and the working posture measurement unit are integrated in the detection unit.

[0010] Beneficial effects: The separate design is conducive to the installation and maintenance of the transient electromagnetic instrument. At the same time, the detection unit integrates multiple functional units, which can realize the integration of drilling trajectory measurement and transient electromagnetic three-component measurement.

[0011] Furthermore, the threaded nest is fixedly connected to the detection bracket and is connected to the housing through threads.

[0012] Beneficial effects: The detection unit is assembled by thread nesting, which has a simple structure and reliable connection, and at the same time has good sealing performance, ensuring the stable operation of the detection unit.

[0013] Furthermore, the detection bracket includes a first mounting part, a second mounting part, a third mounting part, and a fourth mounting part. The first mounting part is used to install the attitude measurement module, the second mounting part is used to install the detection control module, the third mounting part is used to install the transmitting antenna, and the fourth mounting part is used to install the receiving antenna.

[0014] Beneficial effect: Each functional unit uses a different installation part, which can effectively avoid signal interference. At the same time, the functional layout is clear and maintenance is simple.

[0015] Furthermore, the receiving antenna is a mutually orthogonal three-component antenna, including an x-direction coil, a y-direction coil and a z-direction coil.

[0016] Beneficial effect: The three mutually orthogonal receiving antennas can measure three-component signals simultaneously, thereby improving the test efficiency.

[0017] Furthermore, the coil of the receiving antenna needs to perform a calibration step, and the calibration step includes:

[0018] Step 1. Connect the power supply section to supply power and connect to the host computer via WIFI.

[0019] Step 2: Start the host computer software to send a test signal;

[0020] Step 3: Read a certain component voltage signal through the host computer, determine the error range, and fine-tune the coil installation position according to the error range;

[0021] Step 4: Repeat steps 2 and 3 until the error range meets the threshold;

[0022] Step 5, repeat steps 2 to 4 for other component voltage signals;

[0023] Step 6: The calibrated antenna is sealed and fixed with glue.

[0024] Beneficial effect: The installation position of the coil is accurately adjusted by the step of calibrating the error range, and then the step of gluing and fixing is performed, which can effectively ensure that the receiving antenna works reliably under the best measurement accuracy.

[0025] Furthermore, the detection control module includes a transmitting circuit unit, a receiving circuit unit, a main controller, a storage unit and a communication unit. The transmitting circuit unit is electrically connected to the transmitting antenna for generating a pulse electrical signal; the receiving circuit unit is electrically connected to the receiving antenna for sampling the three-component voltage signal; the main controller is electrically connected to the transmitting circuit unit, the receiving circuit unit, the storage unit and the communication unit for controlling the working states of the transmitting antenna and the receiving antenna, and for processing the sampling of the three-component voltage signal to establish time series data. The storage unit is used to store the processed time series data, and the communication unit is used to establish communication with a host computer.

[0026] Beneficial effects: The detection control module has a high degree of integration, including multiple functions such as emission control, data acquisition, data storage, and data communication, and has a simple structure. The large-capacity storage unit enables the transient electromagnetic instrument to store test data for a long time, and can complete long borehole detection without connecting communication cables, effectively reducing system costs.

[0027] Furthermore, the transient electromagnetic instrument detection unit establishes communication with the host computer via WIFI or USB.

[0028] Beneficial effects: Multiple communication methods are used for working parameter setting and data transmission, and operators can flexibly choose according to on-site conditions.

[0029] Furthermore, the shell is made of glass fiber material.

[0030] Beneficial effects: Provides sufficient structural strength without affecting the transmission signal power and receiving sensitivity.

[0031] In another aspect, the present invention provides a transient electromagnetic instrument detection method, comprising the following steps:

[0032] S01. Connect the power receiving interface of the detection unit to the power short section, and connect the power short section to the detection unit. Power on the transient electromagnetic instrument and turn on WIFI.

[0033] S02. Turn on the WIFI switch of the tablet or mobile phone, search and connect to the drilling transient electromagnetic instrument WIFI;

[0034] S03, run the host computer software, set the working parameters of the drilling transient electromagnetic instrument, and start the drilling transient continuous sampling;

[0035] S04, installing the drilling transient electromagnetic instrument to the front end of the drill pipe through the drill pipe adapter;

[0036] S05, using a drilling rig to send a drilling transient electromagnetic instrument into the borehole for measurement, the measurement data includes electromagnetic response information and working posture information, a storage unit is used to save the measurement data, and the upper computer software records the time-scale data of the number of drill rods;

[0037] S06. Remove the drilling transient electromagnetic instrument from the borehole, disconnect the power supply short section and the detection unit, connect the detection unit with a USB cable, and connect the other end to the host computer;

[0038] S07, connect the drilling transient electromagnetic instrument WIFI, run the host computer software, and obtain the stored collected data;

[0039] S08. Disconnect the USB cable, save the collected data, and the host computer software completes the geological body imaging according to the time-scale data of the number of drill rods, the collected data and the working posture information. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 It is the overall structure diagram of transient electromagnetic instrument;

[0041] Figure 2 It is a structural schematic diagram of the detection unit;

[0042] Figure 3 This is a schematic diagram of thread nesting installation;

[0043] Figure 4 It is the flow chart of FPGA logic;

[0044] Figure 5 is the current-off equivalent diagram of the transmitting circuit unit;

[0045] Figure 6It is a structural schematic diagram of the fourth installation part. DETAILED DESCRIPTION

[0046] The following is further described in detail through specific implementation methods:

[0047] The marks in the drawings of the specification include: power short section 1, detection unit 2, shell 3, first mounting part 4, second mounting part 5, third mounting part 6, fourth mounting part 7, threaded nesting 8, attitude measurement module 9, detection control module 10, transmitting antenna 11, Z-direction receiving antenna 12, Y-direction receiving antenna 13, X-direction receiving antenna 14, detection bracket 15, sealing ring groove 16, nested external thread 17, and nested mounting boss 18.

[0048] Embodiment 1

[0049] This embodiment is a transient electromagnetic instrument detection unit, which is powered by a detachable power supply short section 1 and connected to a drill pipe through the power supply short section 1, and uses the drill pipe to achieve long-distance pushing and detection of the transient electromagnetic instrument in the borehole. Figure 1 The rear end of the detection unit 2 is connected to the power supply short section 1 through a thread, and the power supply short section 1 is installed on the top of the drill pipe through the drill pipe adapter, so that the transient electromagnetic instrument can be pushed into the borehole by the drilling rig for measurement.

[0050] The detection unit 2 includes a housing 3 and a detection frame. The detection frame is installed in the housing 3 and includes a detection bracket 15, a threaded nest 8, a detection control module 10, a transmitting antenna 11, a receiving antenna and a posture measurement module 9. Its structure is as follows: Figure 2 shown.

[0051] The shell 3 includes a tubular cavity with a closed front end and an open rear end. An annular boss with an increased diameter is provided near the opening at the rear of the tubular cavity. The inner wall of the shell 3 outside the annular boss is provided with a thread for installing a threaded nest 8 to close the tubular cavity and complete the fixed connection between the detection framework and the shell 3. An inverted conical cavity is provided at the rear end opening of the tubular cavity, and an internal thread is provided on the inner wall of the inverted conical cavity for connecting the power supply short section 1; accordingly, the front end of the power supply short section 1 is designed as a conical structure with a thread, which can be quickly connected to the detection unit 2. The shell 3 is made of glass fiber material, which can ensure the power of the transmitted signal and the sensitivity of the receiving antenna while ensuring the structural strength.

[0052] The end of the detection bracket 15 is connected to the threaded nest 8, and the connection diagram is shown in FIG. Figure 3As shown. The threaded nesting 8 is a cylindrical structure, with a circular groove on the top surface, a sealing ring groove 16 and a nested external thread 17 on the cylindrical surface, and a circular through hole, a threaded nesting mounting hole, a threaded tool hole and a non-threaded tool hole in the center of the bottom surface. A cylindrical nested mounting boss 18 is provided at the end of the detection bracket 15, and the top surface of the nested mounting boss 18 is provided with a cylindrical boss that matches the circular groove of the threaded nesting 8, as well as a mounting hole, a tool hole and a center through hole corresponding to the threaded nesting 8. The threaded nesting 8 can be fixedly connected to the nested mounting boss 18 by using a screw, and the detection skeleton can be pressed in and pulled by screwing a special screw tool into the threaded tool hole. The nested external thread 17 can be tightened with the internal thread of the housing 3 by inserting a special two-pronged tool into the non-threaded tool hole, thereby completing the fixed connection between the detection skeleton and the housing 3. By connecting the threaded nesting 8 and the housing 3, applying glue to the thread, and installing an O-ring in the sealing ring groove 16, a complete sealing layer can be formed for the detection skeleton and the internal device.

[0053] The detection bracket 15 is sequentially arranged along the axial direction with a first mounting portion 4, a second mounting portion 5, a third mounting portion 6, and a fourth mounting portion 7. Figure 2 shown.

[0054] The first mounting portion 4 is used to mount the attitude measurement module 9, which measures the azimuth, tool face angle and inclination information of the detection unit and transmits it to the host computer software to accurately analyze the motion trajectory of the detection unit. The attitude measurement module 9 is fixedly connected to the detection bracket 15 by a pressure strip and screws. A wiring through hole is provided between the first mounting portion 4 and the second mounting portion 5.

[0055] The second mounting portion 5 is used to install the detection control module 10, and the detection control module 10 is fixedly connected to the detection bracket 15 by screws. The detection control module 10 includes a transmitting circuit unit, a receiving circuit unit, a main controller, a storage unit and a communication unit. Among them, the main controller is electrically connected to the transmitting circuit unit, the receiving circuit unit, the storage unit and the communication unit, and is used to control the working state and data acquisition of the transient electromagnetic field, process the sampled data, and establish time series data. In this embodiment, the main controller is implemented using FPGA, preferably using Xilinx's Spartan series. The main modules of the FPGA control logic include: EMMC read-write module, op amp control module, transmission control module, host computer control module, FLASH read-write module, real-time clock read-write module and data acquisition module. The EMMC module is used to control the reading and writing of the storage unit; the operational amplifier control module is used to adjust the gain of the ADC; the transmission control module is used to control the generation of pulse current; the host computer control module receives the control instructions of the host computer to complete the setting of working parameters and data reading; the FLASH read-write module is used to store the working parameters of the transient electromagnetic instrument, such as sampling frequency and sampling interval time; the real-time clock read-write module provides time stamp information for the stored data; the data acquisition module completes the AD conversion of the three-component voltage signal. The flowchart of the FPGA control logic is as follows Figure 4 shown.

[0056] The transmitting circuit unit is electrically connected to the transmitting antenna 11, and transmits a bipolar pulse current to the transmitting antenna 11. The performance of the transient electromagnetic instrument transmitter is related to the shutdown time of the current. The smaller the shutdown time, the more complete the early signal of the induced secondary field is detected by the receiver, and the shallow geological exploration is more accurate. In order to reduce the shutdown time and shorten the blind area of ​​shallow detection, this embodiment designs a fast shutdown transmitter, and uses the internal diode of the field effect tube to build a fast discharge circuit. The transmitter includes an H-bridge drive part. During transmission, Q2 and Q3 short-circuit R. At the moment of transmission shutdown, the parasitic diode inside the field effect tube of the bridge circuit forms a fast discharge circuit, and the inductive load energy stored in the transmitting coil will be quickly released, greatly shortening the shutdown time. The current shutdown equivalent diagram of the transmitting circuit unit is shown in the figure below. Figure 5 shown.

[0057] The receiving circuit unit is electrically connected to the receiving antenna and is used to sample the three-component voltage signal of the receiving antenna. In this embodiment, the receiving circuit unit passes each component signal through two operational amplifiers with different amplification factors, and then uses a 24-bit ADC for voltage sampling. The results of the two samplings are spliced ​​to obtain the sampling value of the voltage signal. A total of 6 groups of ADCs are required for the three-component voltage signal. The resolution can be doubled by collecting in two groups.

[0058] The storage unit is used to store the spliced ​​sampling data and the working attitude information of the detection unit. In this embodiment, the storage unit is implemented by a large-capacity and high-speed EMMC chip. Since the transient electromagnetic instrument continuously measures as the drill rod advances, it is necessary to align the time and depth of the recorded data. The host computer integrates and processes the collected data according to the corresponding relationship between the time mark and the drill rod depth.

[0059] The communication unit is used to establish communication with the host computer. In this embodiment, the communication unit includes a USB module and a WIFI module. The USB module is used by the host computer to read the stored collected data, and the WIFI module is used to configure the working parameters of the transient electromagnetic instrument and transmit a small amount of collected data. After the detection unit is powered on, the main controller controls to automatically turn on the WIFI.

[0060] In this embodiment, the host computer can be a tablet computer, a PC or an explosion-proof mobile phone. The functions of the host computer software include parameter setting, data acquisition, data transmission, data analysis, data processing, data imaging, etc. Parameter setting includes setting the parameters of the transmitting coil and the receiving coil, the number of superpositions, the sending cycle, etc.; data acquisition refers to controlling the start or stop of data acquisition; data transmission uses WIFI or USB to communicate with the borehole transient electromagnetic instrument to transmit the collected data to the computer; data analysis refers to parsing the collected data and extracting the data information of the measuring point; data processing refers to preprocessing the borehole transient data, including abnormal elimination, curve smoothing, etc., apparent resistivity calculation, time-depth calculation; data display includes display of measuring point attenuation curves, display of multi-channel curves, and display of contour maps.

[0061] The detection control module 10 is also provided with a receiving wire, which passes through the wiring through hole between the first mounting portion 4 and the second mounting portion 5, the through hole at the end of the detection bracket 15, and the central through hole of the threaded nest 8 in sequence. A power receiving interface is provided at the end of the receiving wire, which is connected to the power supply interface of the power supply short section. In this embodiment, the power receiving interface adopts a USB interface, which is also used to establish USB communication with the host computer to transmit data.

[0062] The third mounting portion 6 is used to mount a transmitting antenna 11, which converts the pulse circuit generated by the transmitting circuit unit into a pulse magnetic field. In this embodiment, the transmitting antenna 11 is arranged along the axial direction of the detection unit and can withstand a current of no less than 3.3 A. A wiring groove parallel to the axial direction of the detection bracket 15 is provided between the second mounting portion 5 and the third mounting portion 6, and between the third mounting portion 6 and the fourth mounting portion 7.

[0063] The fourth mounting portion 7 is used to mount the receiving antenna. The receiving antenna in this embodiment is a mutually orthogonal three-component antenna, with a structure as shown in FIG. Figure 2 As shown, the structure of the fourth mounting portion 7 is as follows Figure 6As shown. In the fourth mounting portion 7, mounting portions of the Z-direction receiving antenna 12, the Y-direction receiving antenna 13 and the X-direction receiving antenna 14 are arranged in sequence from back to front. Among them, the mounting portions of the Z-direction receiving antenna 12 and the Y-direction receiving antenna 13 are circular grooves perpendicular to the outer surface of the detection bracket 15, and a concave platform with a mounting hole is arranged in the circular groove; the mounting portion of the X-direction receiving antenna 14 is a circular groove arranged at the top of the detection bracket 15, and the diameter and depth of the circular groove are slightly larger than the coil size of the X-direction receiving antenna. The coil axis of the Z-direction receiving antenna 12 is located in the same horizontal plane as the center line of the routing groove and is perpendicular to the axial direction of the detection bracket 15; the coil axis of the Y-direction receiving antenna 13 is rotated 90 degrees counterclockwise along the coil axis of the Z-direction receiving antenna 14 and is perpendicular to the axial direction of the detection bracket 15; the coil axis of the X-direction receiving antenna 14 is the same as the axial direction of the detection bracket 15. The Y-direction receiving antenna 13 and the Z-direction receiving antenna 12 are installed and adjusted in position by screws. In this embodiment, the number of turns of each directional coil is not less than 1000 turns.

[0064] In order to achieve accurate measurement of the electromagnetic response in each component direction, the installed three-component antenna needs to be calibrated. The calibration steps are as follows:

[0065] Step 1. Connect the power supply section to supply power and connect to the host computer via WIFI.

[0066] Step 2: Run the host computer software to send a test signal;

[0067] Step 3: Read a certain component voltage signal through the host computer, determine the error range, and fine-tune the coil installation position;

[0068] Step 4: Repeat steps 2 and 3 until the error range meets the threshold;

[0069] Step 5, repeat steps 2 to 4 for other component voltage signals;

[0070] Step 6: The calibrated antenna is sealed and fixed with glue.

[0071] In this embodiment, there is no geological body near the detection unit during calibration, and the test signal should not cause the generation of a secondary induced magnetic field, so the threshold of the error range is set so that the component voltage signal does not exceed 10mv within 60 microseconds.

[0072] Embodiment 2

[0073] This embodiment is a transient electromagnetic instrument detection method, comprising the following steps:

[0074] S01. Connect the power receiving interface of the detection unit to the power supply interface of the power supply short section, and connect the power supply short section to the detection unit, and power on the transient electromagnetic instrument to turn on WIFI;

[0075] S02. Turn on the WIFI switch of the tablet or mobile phone, search and connect to the drilling transient electromagnetic instrument WIFI;

[0076] S03, run the host computer software, set the working parameters of the drilling transient electromagnetic instrument, and start the drilling transient continuous sampling;

[0077] S04, installing the drilling transient electromagnetic instrument to the front end of the drill pipe through the drill pipe adapter;

[0078] S05, using a drilling rig to send a drilling transient electromagnetic instrument into the borehole for measurement, the measurement data includes electromagnetic response information and working posture information, a storage unit is used to save the measurement data, and the upper computer software records the time-scale data of the number of drill rods;

[0079] S06. Remove the drilling transient electromagnetic instrument from the borehole, disconnect the power supply short section and the detection unit, connect the detection unit with a USB cable, and connect the other end to the host computer;

[0080] S07, connect the drilling transient electromagnetic instrument WIFI, run the host computer software, and obtain the stored collected data;

[0081] S08. Disconnect the USB cable, save the collected data, and the host computer software completes the geological body imaging according to the time-scale data of the number of drill rods, the collected data and the working posture information.

[0082] The above are only embodiments of the present invention. The invention is not limited to the field involved in this implementation case. The common knowledge such as the known specific structure and characteristics in the scheme is not described in detail here. It should be pointed out that for those skilled in the art, several deformations and improvements can be made without departing from the structure of the present invention, which should also be regarded as the protection scope of the present invention, and these will not affect the effect of the implementation of the present invention and the practicality of the patent. The scope of protection required by this application shall be based on the content of its claims, and the specific implementation methods and other records in the specification can be used to interpret the content of the claims.

Claims

1. A transient electromagnetic instrument detection unit, characterized in that: It is powered by a detachable power supply short section and connected to the drill pipe, and includes a shell and a detection skeleton. The detection skeleton is installed in the shell. The detection skeleton includes a detection bracket, a threaded nest, a detection control module, a transmitting antenna, a receiving antenna and a posture measurement module. The receiving antenna is used to measure the three-component magnetic field change information, and the posture measurement module is used to measure the working posture information of the detection unit.

2. A transient electromagnetic instrument detection unit according to claim 1, characterized in that: The threaded nest is fixedly connected to the detection bracket and is connected to the housing through threads.

3. A transient electromagnetic instrument detection unit according to claim 2, characterized in that: The detection bracket includes a first mounting part, a second mounting part, a third mounting part, and a fourth mounting part. The first mounting part is used to install a posture measurement module, the second mounting part is used to install a detection control module, the third mounting part is used to install a transmitting antenna, and the fourth mounting part is used to install a receiving antenna.

4. A transient electromagnetic instrument detection unit according to claim 1, characterized in that: The receiving antenna is a mutually orthogonal three-component antenna, including an x-direction coil, a y-direction coil and a z-direction coil.

5. A transient electromagnetic instrument detection unit according to claim 4, characterized in that: The coil of the receiving antenna needs to perform a calibration step, and the calibration step includes: Step 1. Connect the power supply section to supply power and connect to the host computer via WIFI. Step 2: Start the host computer software to send a test signal; Step 3: Read a certain component voltage signal through the host computer, determine the error range, and fine-tune the coil installation position according to the error range; Step 4: Repeat steps 2 and 3 until the error range meets the threshold; Step 5, repeat steps 2 to 4 for other component voltage signals; Step 6: The calibrated antenna is sealed and fixed with glue.

6. A transient electromagnetic instrument detection unit according to claim 1, characterized in that: The detection control module includes a transmitting circuit unit, a receiving circuit unit, a main controller, a storage unit and a communication unit. The transmitting circuit unit is electrically connected to the transmitting antenna for generating a pulse electrical signal; the receiving circuit unit is electrically connected to the receiving antenna for sampling the three-component voltage signal; the main controller is electrically connected to the transmitting circuit unit, the receiving circuit unit, the storage unit and the communication unit for controlling the working states of the transmitting antenna and the receiving antenna, and is also used to process the sampling of the three-component voltage signal to establish time series data. The storage unit is used to store the processed time series data, and the communication unit is used to establish communication with a host computer.

7. A transient electromagnetic instrument detection unit according to claim 1, characterized in that: The transient electromagnetic instrument detection unit establishes communication with the host computer via WIFI or USB.

8. The transient electromagnetic instrument detection unit according to claim 1, characterized in that: The housing is made of fiberglass material.

9. A transient electromagnetic instrument detection method, characterized in that: The following steps are involved: S01. Connect the power receiving interface of the detection unit to the power short section, and connect the power short section to the detection unit. Power on the transient electromagnetic instrument and turn on WIFI. S02. Turn on the WIFI switch of the tablet or mobile phone, search and connect to the drilling transient electromagnetic instrument WIFI; S03, run the host computer software, set the working parameters of the drilling transient electromagnetic instrument, and start the drilling transient continuous sampling; S04, installing the drilling transient electromagnetic instrument to the front end of the drill pipe through the drill pipe adapter; S05, using a drilling rig to send a drilling transient electromagnetic instrument into the borehole for measurement, the measurement data includes electromagnetic response information and working posture information, a storage unit is used to save the measurement data, and the upper computer software records the time-scale data of the number of drill rods; S06. Remove the drilling transient electromagnetic instrument from the borehole, disconnect the power supply short section and the detection unit, connect the detection unit with a USB cable, and connect the other end to the host computer; S07, connect the drilling transient electromagnetic instrument WIFI, run the host computer software, and obtain the stored collected data; S08. Disconnect the USB cable, save the collected data, and the host computer software completes the geological body imaging according to the time-scale data of the number of drill rods, the collected data and the working posture information.

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