A borehole bottom transient electromagnetic water disaster real-time detection device and method

Abstract

The application discloses a kind of drilling hole bottom transient electromagnetic water disaster real-time detection device, using hydraulic drive rotating coil mode to realize to the hidden water disaster in the radial certain range of drilling hole bottom is inquired, using hole bottom relay and cable drilling rod internal signal transmission line etc. Conventional method can be realized with the connection of detection device, realize the real-time transmission of hole bottom data, provide timeliness guidance for drilling, break through the drawbacks of the increase of secondary push workload, timeliness is not enough. At the same time, the power supply component driven by the principle of hydroelectric power is arranged in the detection device, which can meet the power supply of the equipment under long-term use, and the two independent battery charging, power supply periodic switching mode continuously supports the rotating transmitting rotating coil work, breaks through the battery capacity limit, and provides guarantee for real-time detection.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of geophysical exploration, and particularly relates to a drilling bottom transient electromagnetic water disaster real-time detection device and method. BACKGROUND

[0002] Coal mine water disaster accident exploration is an important link in daily work, and is usually carried out before tunneling / mining, through conventional geophysical exploration means or advance construction drilling, to achieve the purpose of exploring water disaster / structure in advance. In the field of coal mine geological disaster / water disaster advanced exploration, the exploration work is basically independent, that is, it is carried out in the process of completion of other procedures or waiting.

[0003] The previous various water disaster advanced detection methods have an advanced detection distance generally within 100 m. The original exploration distance has been far from meeting the requirements. If the exploration distance or exploration mode is not changed, to meet the safety requirements, the detection work must be maintained at a frequency of once every 1-2 days, which will undoubtedly cause the stagnation of tunneling and bring heavy burden to the detection construction personnel. For the mine with efficient operation, it is unacceptable.

[0004] The underground various geophysical exploration data currently still stays in the state of self-storage to part data access ring network, and cannot achieve the purpose of seamless connection of exploration results and drilling / tunneling construction and guide drilling, especially for the water disaster exploration results in the drilling hole, which has a large gap with the goal of guiding drilling direction, revealing structure and water disaster early warning. There are generally problems of being unable to conduct omnidirectional exploration on the hole bottom, being unable to solve the long-time power supply of hole bottom equipment, and being difficult to transmit the hole bottom data to the hole mouth, so as to realize the demand of dynamic real-time transmission, continuous processing and timely feedback. SUMMARY

[0005] The present application aims to provide a drilling hole bottom transient electromagnetic water disaster real-time detection device and method, to solve the problem of the hole bottom water disaster detection device in the prior art being unable to meet the dynamic real-time transmission, continuous processing and timely feedback.

[0006] In order to solve the above technical problems, the present application adopts the following technical solutions:

[0007] A drilling hole bottom transient electromagnetic water disaster real-time detection device, comprising a drill bit, the rear part of the drill bit being connected with a drill rod, the rear part of the drill rod being connected with a detection device, the detection device being in the shape of a pipe with the same specification as the drill rod, and the rear part of the detection device being capable of being connected with multiple drill rods in sequence;

[0008] The detection device is coaxially fixedly provided with a launch tube in the middle part, and there is an annular space between the launch tube and the detection device, forming a water passage; and the detection device is coaxially rotatably provided with a power generation paddle in the front part.

[0009] The detection device is coaxial and rotates into a rotating shaft, and the rotating shaft is sequentially provided from front to back with a posture measuring device, a rotating coil, a rotating damper and a rotating paddle.

[0010] The inside of the launching tube is also provided with a charging and power supply assembly, which includes a charging battery, a power supply battery, a controller, a wireless transmitter and a receiver.

[0011] The rotating coil is used to transmit and receive voltage and current data and transmit it to the receiver.

[0012] The controller is used to control the emission current in the rotating coil, thereby switching the emission and reception state of the rotating coil.

[0013] The output end of the power generation paddle is connected with the charging battery, which is used to power the charging battery.

[0014] The charging battery is used to power the rotating coil, the controller, the wireless transmitter and the receiver after the power supply battery is depleted.

[0015] The power supply battery is used to power the rotating coil, the controller, the wireless transmitter and the receiver.

[0016] The receiver is used to receive the data transmitted by the rotating coil and transmit it to the wireless transmitter.

[0017] The wireless transmitter is used to transmit the received information to an external wireless receiving device.

[0018] Further, the detection device is a non-metal drill rod.

[0019] Further, the detection device is fixedly connected with the launching tube through the inner tube support ring.

[0020] Further, it also includes a generator, the rotating paddle is connected with the input end of the generator, and the output end of the generator is connected with the charging battery.

[0021] A drilling hole bottom transient electromagnetic water damage real-time detection method, which is based on the above-mentioned drilling hole bottom transient electromagnetic water damage real-time detection device, includes the following steps:

[0022] Step 1, determine the area to be drilled, design the original drilling trajectory and drilling endpoint in the area to be detected.

[0023] Step 2, drilling along the original drilling trajectory, after the first drill rod is lowered, the detection device is connected behind the first drill rod; a drill rod is connected behind the detection device to continue drilling;

[0024] Step 3, real-time borehole transient electromagnetic detection is performed using the detection device; until the drill rod connected this time is completely inside the borehole, the drilling this time is completed;

[0025] Step 4, the external wireless receiving device receives the voltage and current data detected by the detection device in this drilling and transmits them to the ground server, the ground server obtains the borehole transient electromagnetic detection data according to the received voltage data, and then judges whether the drilling trajectory needs to be adjusted;

[0026] If yes, the drilling trajectory is redesigned, a drill rod is connected behind the last drill rod, and drilling is performed according to the redesigned drilling trajectory;

[0027] If no, a drill rod is connected behind the last drill rod, and drilling is continued according to the last designed drilling trajectory;

[0028] Step 5, repeat steps 3-4 until the drilling endpoint is reached, the drilling operation is completed, and the borehole transient electromagnetic detection data is obtained.

[0029] Further, the borehole transient electromagnetic detection data in step 4 includes data of resistivity changing with time and depth, wherein the resistivity is obtained by the following formula:

[0030]

[0031] Wherein, ρ s represents resistivity;

[0032] μ0 represents the magnetic permeability of vacuum;

[0033] s represents the area of the receiving coil;

[0034] n represents the number of turns of the receiving coil;

[0035] S represents the area of the transmitting coil;

[0036] N represents the number of turns of the receiving coil;

[0037] Wherein, the transmitting coil and the receiving coil are both rotating coils, s=S; n=N;

[0038] t represents the real-time time of observation;

[0039] V represents the voltage of the rotating coil 6 at the time of observation;

[0040] I represents the current of the rotating coil at the time of observation;

[0041] C represents a regulation coefficient, which is related to the lithology of the measuring point.

[0042] Further, the resistivity in step 4 at a certain moment corresponds to the depth through the following steps:

[0043] Step a, using the following formula, the detection depth at each moment corresponds to the calculation depth:

[0044]

[0045] Wherein, h i represents the calculation depth corresponding to the detection depth at the i-th moment;

[0046] t i represents the time corresponding to the observation time at the i-th moment;

[0047] p i represents the resistivity corresponding to the i-th moment;

[0048] sigma represents the reciprocal of the resistivity corresponding to the i-th moment;

[0049] Step b, using the following formula, the actual depth H i at each moment:

[0050]

[0051] Wherein, K represents the full space coefficient.

[0052] Compared with the prior art, the present application has the following technical effects:

[0053] (I) The drilling hole bottom transient electromagnetic water disaster real-time detection device adopts a hydraulic power rotating coil mode to realize the detection of hidden water disasters within a certain range of the drilling hole bottom, and can realize the connection with the detection device and the real-time transmission of the hole bottom data by using conventional methods such as hole bottom relay and cable inside signal transmission line, etc., thereby providing time-effective guidance for drilling and breaking through the disadvantages of increased secondary pushing workload and insufficient timeliness.

[0054] Meanwhile, the water power generation principle driven power supply assembly is arranged in the detection device, which can meet the power supply of the equipment under long-time use, and the two independent battery charging and power supply periodically switch to continuously support the rotating emission rotating coil work, thereby breaking through the battery capacity limit and providing guarantee for real-time detection.

[0055] (II) The borehole bottom transient electromagnetic water disaster real-time detection method of the present application discloses a method for calculating resistivity and depth, and through the above method, the change rule of resistivity with time and borehole radial depth can be obtained, thereby providing a favorable theoretical basis for judging whether a drilling area has a water disaster and providing data support for water disaster advanced detection, and being suitable for large-scale use and promotion in industry. BRIEF DESCRIPTION OF DRAWINGS

[0056] Figure 1 is a schematic diagram of the overall structure of the borehole bottom transient electromagnetic water disaster real-time detection device of the present application;

[0057] Figure 2 is a schematic diagram of the internal structure of the detection device in the present application;

[0058] Figure 3 is a schematic diagram of the internal structure of the transmitting tube in the present application;

[0059] Figure 4 is a schematic diagram of the detection principle of the detection device of the present application;

[0060] Figure 5 is a schematic diagram of the change of the induced voltage of the rotating coil with time in an embodiment of the present application.

[0061] The meanings of the respective reference numerals in the drawings are as follows:

[0062] 1, detection device; 2, transmitting tube; 3, power generation paddle; 4, rotating shaft; 5, attitude measurement device; 6, rotating coil; 7, rotation damper; 8, rotating paddle; 9, power supply component; 10, inner tube support ring; 11, generator. DETAILED DESCRIPTION

[0063] It should be noted that all components in the present application, if not specifically stated, are all components known in the prior art. For example, the rotation damper is a commonly known rotation damper.

[0064] The following gives a specific embodiment of the present application, and it should be noted that the present application is not limited to the following specific embodiment, and any equivalent transformation made on the basis of the technical solutions of the present application falls within the protection scope of the present application.

[0065] As shown in Figures 1-3 A borehole bottom transient electromagnetic water disaster real-time detection device, comprising a drill bit, a drill rod connected to the rear of the drill bit, a detection device 1 connected to the rear of the drill rod, the detection device 1 being a tubular shape with the same specification as the drill rod, and a plurality of drill rods being able to be connected to the rear of the detection device 1 in sequence;

[0066] The detector 1 has a coaxial and fixedly installed transmitter tube 2 in the middle, and there is an annular zone between the transmitter tube 2 and the detector 1 to form a water passage; the detector 1 has a coaxial and rotatably installed generator blade 3 in the front.

[0067] A rotating shaft 4 is coaxially inserted inside the detection device 1. From front to back, the rotating shaft 4 is equipped with an attitude measuring device 5, a rotating coil 6, a rotating damper 7, and a rotating blade 8. The attitude measuring device 5 and the rotating coil 6 are located inside the launch tube 2, and the rotating damper 7 and the rotating blade 8 are located at the rear of the launch tube 2.

[0068] The transmitter tube 2 is also equipped with a charging and power supply component 9, which includes a rechargeable battery, a power supply battery, a controller, a wireless transmitter, and a receiver.

[0069] The rotating coil 6 is used to transmit and receive voltage and current data and transmit it to the receiver;

[0070] The controller is used to control the transmitting current in the rotating coil 6, thereby switching the transmitting and receiving states of the rotating coil 6;

[0071] The output end of the power generation blade 3 is connected to the rechargeable battery to supply power to the rechargeable battery;

[0072] The rechargeable battery is used to supply power to the rotating coil 6, the controller, the wireless transmitter, and the receiver after the power supply battery is depleted.

[0073] The aforementioned power supply battery is used to power the rotating coil, controller, wireless transmitter, and receiver;

[0074] The receiver is used to receive data transmitted by the rotating coil 6 and transmit it to the wireless transmitter;

[0075] The wireless transmitter is used to transmit the received information to an external wireless receiving device.

[0076] Furthermore, to ensure the continuous operation of the transient electromagnetic at the bottom of the hole, a self-generated power generation method at the bottom of the hole is used to continuously charge the battery. The charging and power supply component 9 can adopt a commonly used charging and power supply circuit known in the prior art.

[0077] In addition to using commonly used charging and power supply circuits known in the prior art, this embodiment provides a specific implementation method, such as... Figure 3 As shown, the charging and power supply component 9 consists of two independent batteries. The power supply battery is connected to the device at the bottom of the hole, and the charging battery is directly connected to the generator 11.

[0078] Wherein, the charging battery and the power supply battery are provided with double-throw switches, according to the conventional selection, the switch is used to control the battery to be in the power supply state or the charging state, the control switch is installed on the charging circuit, in the process of drilling, the water power drives the power generation paddle 3 to rotate to generate electricity to supply power for the charging battery, the control switch is installed on the charging battery circuit, when the battery voltage reaches or exceeds the set value, the control switch in the circuit will be disconnected, the charging battery and the power supply battery are switched with each other. The charging battery is switched with the power supply battery after the power supply battery runs out of power, and the original power supply battery is charged.

[0079] Wherein, the control switch uses the known existing control switch, and the control of other components uses the known existing algorithm. The remaining components not specifically described use known existing components, such as the wireless transmitter, which can use a Bluetooth short transmission device according to conventional selection.

[0080] Figure 4 The principle diagram for realizing radial measurement is given, and the transmitting rotating coil and the receiving rotating coil are the same rotating coil. In the drilling process, the rotating coil rotates periodically around the rotation axis to realize omnidirectional scanning of the borehole radial.

[0081] In the power supply stage, a constant current with intensity I flows in the rotating coil, and the current generates a stable magnetic field H0 in space. At t1 moment, the current in the rotating coil disappears. According to Faraday's law of electromagnetic induction, the magnetic field distributed in space will not disappear immediately, and the vortex current in the formation will maintain the original magnetic field. The magnetic field generated by the vortex current is the secondary field H1.

[0082] At different moments after power failure, the depth, radius and intensity of the equivalent eddy current will gradually change. Correspondingly, the secondary magnetic field also changes with time and gradually decays. The magnetic field induces a voltage in the receiving rotating coil, which is received by the borehole equipment. The size of the induced secondary voltage at different moments in the transmitting direction is recorded, and the resistivity change with depth in that direction is obtained.

[0083] The rotating coil can obtain the resistivity change within a certain distance in one direction by detecting in one direction. By detecting in multiple angles at one point, the resistivity change with depth within 360 degrees at the measurement point can be obtained, achieving the purpose of omnidirectional exploration of the concealed water-bearing body within a certain range beside the borehole.

[0084] Since radial 360° exploration is required, the rotating coil needs to be continuously rotated to adjust the transmitting direction. In actual coal seam drilling engineering, the drill rod as a whole does not rotate, but the drill bit itself rotates by hydraulic power to break rocks. Under the premise that the drill rod does not move, the transmitting rotating coil must rely on its own power to realize the adjustment of the detection direction. To solve the problem of rotating the transmitting rotating coil,

[0085] Figure 5 is a schematic diagram of the time-varying induced voltage of the magnetic field generated by the formation eddy current in the rotating coil in this embodiment. The horizontal axis is time, and the vertical axis is voltage. During data acquisition, 40-100 time points are generally selected within 1us to 100ms to record the signal values at the corresponding time points.

[0086] This embodiment adopts a high-pressure jetting coaxial driving mode, that is, the rotating paddle 8 is driven to rotate by a high-pressure water column, and the rotating paddle 8 drives the coaxial launch rotating coil to rotate. The high-speed water flow drives the rotating paddle 8 to rotate, and according to the water pressure of the high-speed water column, the rotating damper 7 is configured with appropriate rotating damping for the rotating paddle 8 to drive the rotating coil to rotate periodically at the actual required speed. At the same time, a posture measuring device is installed on the rotating shaft 4 to measure the real-time exploration orientation.

[0087] The posture measuring device is a commonly used device known in the prior art, and specifically, a roll angle measuring device can be used.

[0088] As a preferred scheme, the detection device 1 is a non-metal drill rod.

[0089] As a preferred scheme, the detection device 1 is fixedly connected with the launch pipe 2 through the inner pipe support ring 10. The connection strength of the detection device 1 and the launch pipe 2 is strengthened.

[0090] As a preferred scheme, the power generation paddle 3 is connected with the input end of the generator 11, and the output end of the generator 11 is connected with the charging battery. The power generation paddle 3 drives the generator 11 to generate power, and then supplies power to the power supply assembly 9.

[0091] This embodiment adopts the water-driven rotating coil to realize the exploration of the hidden water disaster within a certain range of the radial direction of the borehole bottom, and uses the water-driven mode to continuously charge the battery at the bottom of the hole, so as to realize the goal of long-time and all-around real-time exploration. Compared with the prior art, the method proposed in this embodiment has the following advantages:

[0092] Firstly, the conventional borehole transient electromagnetic method adopts a secondary pushing mode, that is, after the drilling construction work is completed, the borehole transient electromagnetic probe is pushed into the borehole for exploration, and after the exploration is completed, the probe pipe is taken out and the data in the probe pipe is exported, and the data is analyzed to obtain the distribution of the hidden water disaster within a certain range of the radial direction of the whole borehole section.

[0093] In this exploration mode, the exploration process is separated from the drilling process, and the radial water disaster distribution result of the borehole lags far behind the drilling construction process, and cannot provide effective guidance for the drilling process. By using the method of this embodiment, the drilling process and the detection process can be seamlessly combined to realize drilling and exploration at the same time, and the detection effect is greatly enhanced in timeliness.

[0094] Secondly, the detection and interpretation of water damage are independent of the drilling process in the secondary push mode, the exploration data and results cannot be immediately reflected in various data platforms of coal mines, the automation and intelligence degree is not enough, and the real-time transmission and synchronous uploading of data to the network cannot meet the development and construction needs of the current intelligent mine and transparent mine, can greatly improve the intelligent level of underground exploration work, and is more in line with the needs of the current era to improve new quality productivity.

[0095] A drilling hole bottom transient electromagnetic water damage real-time detection method, the drilling hole bottom transient electromagnetic water damage real-time detection device, comprises the following steps:

[0096] Step 1, determine the area to be drilled, design the original drilling trajectory and drilling endpoint in the area to be detected;

[0097] Step 2, drill according to the original drilling trajectory, connect the detection device 1 to the rear of the first drill rod after the first drill rod is lowered; continue drilling by connecting a drill rod to the rear of the detection device 1;

[0098] Step 3, use the detection device 1 to perform real-time transient electromagnetic detection in the hole; until the drill rod connected this time is completely inside the drilling hole, the drilling is completed;

[0099] Specifically, in the drilling process, the high-pressure water flow in the drilling hole has three effects:

[0100] 1. Push the generator at the bottom of the hole to generate electricity and continuously charge the instrument battery;

[0101] 2. Push the transmitting coil to rotate continuously to realize exploration at different angles in the radial direction of the drilling hole

[0102] 3. The high-pressure water flow pushes the drill bit to rotate and break the rock layer, increasing the drilling depth;

[0103] According to the conventional selection in the art, the detection device 1 stores the measured data in the relay at the bottom of the hole. In actual use, when the drilling depth increases by the length of a drill rod (usually 2-3 m), the tail end of the drill rod is removed, the signal receiver is connected to the through-cable signal line inside the drill rod, and the stored signals in the relay are transmitted to the signal receiver through the through-cable signal line;

[0104] Step 4, the external wireless receiving device receives the voltage data detected by the detection device 1 in this drilling and transmits it to the ground server, the ground server obtains the transient electromagnetic detection data in the hole according to the received data, and then judges whether the drilling trajectory needs to be adjusted;

[0105] If so, redesign the drilling trajectory, connect a drill rod to the rear of the last drill rod, and drill according to the redesigned drilling trajectory;

[0106] If not, a drill pipe is connected to the rear of the last drill pipe, and drilling is continued according to the last designed drilling track;

[0107] Specifically, after the ground server receives the data, the data can be processed using a known and commonly used automatic data processing program to automatically generate an exploration report, and the next drilling construction process is determined according to the exploration report. Those skilled in the art can also make a judgment.

[0108] After the data transmission is completed, the connection between the borehole signal receiver and the internal cable signal line of the drill pipe is disconnected, a drill pipe is connected to the tail end of the drill pipe, and a tail end pumping device is connected to the tail end of the new drill pipe. The high-pressure water flow continues to push the drill bit to crush rocks and rotate the transmitting coil to collect data and charge the battery at the same time.

[0109] Step 5, repeat steps 3-4 until the drilling endpoint is reached, and the drilling operation is completed; all borehole transient electromagnetic exploration data is obtained. According to the obtained borehole transient electromagnetic data, real-time detection of borehole water damage can be realized, and the electrical property changes of the rock formation within a certain range of the borehole bottom are continuously revealed during drilling, providing timely guidance for drilling.

[0110] Further, the borehole transient electromagnetic exploration data detected by the detection device 1 in step 4 includes data of the change of resistivity with time and depth, wherein the resistivity is obtained by the following formula:

[0111]

[0112] wherein ρ s represents the resistivity;

[0113] μ0 represents the vacuum permeability;

[0114] s represents the receiving rotating coil area;

[0115] n represents the number of turns of the receiving rotating coil;

[0116] S represents the transmitting rotating coil area;

[0117] N represents the number of turns of the receiving rotating coil;

[0118] wherein the transmitting coil and the receiving coil are both rotating coils, s=S; n=N;

[0119] t represents the real-time time at the time of observation;

[0120] V represents the voltage of the rotating coil at the time of observation;

[0121] I represents the current of the rotating coil at the time of observation;

[0122] C represents a regulation coefficient, which is related to the lithology of the measuring point and is determined by a person skilled in the art according to the actual geological conditions of the local area.

[0123] Further, the resistivity in step 4 in step 4 at a certain moment corresponds to the depth of the resistivity by the following steps:

[0124] Step a, using the following formula, the detection depth at each moment corresponds to the calculation depth:

[0125]

[0126] Wherein, h i represents the calculation depth corresponding to the detection depth at the i th moment;

[0127] t i represents the time corresponding to the observation time at the i th moment;

[0128] p i represents the resistivity corresponding to the i th moment;

[0129] s represents the reciprocal of the resistivity corresponding to the i th moment;

[0130] Step b, considering that the secondary field in the coil is generated by the transmitting coil, it can be considered that the calculation depth is the distance of double path of electromagnetic wave, so it is necessary to subtract half depth. Using the following formula, the actual depth H i at each moment:

[0131]

[0132] Wherein, K represents the full space coefficient. The full space coefficient K changes with the detection environment, and is generally obtained by experience or experimental means. A person skilled in the art is capable of confirming the value of the full space coefficient K according to the actual situation.

Claims

1. A drilling hole bottom transient electromagnetic water disaster real-time detection device, comprising a drill bit, characterized in that, The drill bit is connected with a drill rod, and the drill rod is connected with a detection device (1). The detection device (1) is coaxially fixed with a launching tube (2) in the middle part, and an annular space is formed between the launching tube (2) and the detection device (1) to form a water passage. The detection device (1) is coaxially and rotatably penetrated by a rotating shaft (4), and the rotating shaft (4) is sequentially provided from front to back with a posture measuring device (5), a rotating coil (6), a rotating damper (7) and a rotating paddle (8). The detection device (1) is coaxially fixed with a launching tube (2) in the middle part, and an annular space is formed between the launching tube (2) and the detection device (1) to form a water passage. The launching tube (2) is further provided with a power charging and supplying assembly (9), which includes a charging battery, a power supply battery, a controller, a wireless transmitter and a receiver. The rotating coil (6) is used for transmitting and receiving voltage and current data and transmitting to the receiver. The controller is used for controlling the transmitting current in the rotating coil (6), and then switching the transmitting and receiving states of the rotating coil (6). The output end of the power generation paddle (3) is connected with the charging battery, which is used for supplying power to the charging battery. The charging battery is used for supplying power to the rotating coil (6), the controller, the wireless transmitter and the receiver after the power supply battery is exhausted. The power supply battery is used for supplying power to the rotating coil, the controller, the wireless transmitter and the receiver. The receiver is used for receiving the data transmitted by the rotating coil (6) and transmitting to the wireless transmitter.

2. The borehole bottom transient electromagnetic water hazard real-time detection device of claim 1, wherein, The wireless transmitter is used for transmitting the received information to the external wireless receiving device.

3. The borehole bottom transient electromagnetic water hazard real-time detection device of claim 2, wherein, The detection device (1) is a non-metal drill rod.

4. The borehole bottom transient electromagnetic water hazard real-time detection device of claim 3, wherein, The detection device (1) is fixedly connected with the launching tube (2) through the inner tube support ring (10).

5. A method for real-time detection of water disasters at the bottom of a borehole by using transient electromagnetic method, which is based on the device for real-time detection of water disasters at the bottom of a borehole by using transient electromagnetic method according to claim 4, characterized in that, The power generation paddle (3) is connected with the input end of the generator (11), and the output end of the generator (11) is connected with the charging battery. The steps include: Step 1, determining the area to be drilled, designing the original drilling trajectory and drilling endpoint in the area to be detected; Step 2, drilling according to the original drilling trajectory, connecting the detection device (1) at the rear of the first drill rod after the first drill rod is lowered, and connecting a drill rod at the rear of the detection device (1) to continue drilling; Step 3, using the detection device (1) to perform real-time borehole transient electromagnetic detection; until the drill rod connected this time completely enters the borehole, and the drilling this time is completed; Step 4, the external wireless receiving device receives the voltage and current data detected by the detection device (1) in this drilling and transmits to the ground server, and the ground server obtains the borehole transient electromagnetic detection data according to the received voltage data, and then judges whether the drilling trajectory needs to be adjusted. If yes, redesign the drilling trajectory, connect a new drill pipe behind the last drill pipe, and drill according to the redesigned drilling trajectory; If no, connect a new drill pipe behind the last drill pipe, and continue drilling according to the last designed drilling trajectory; Step 5, repeat steps 3-4 until the drilling endpoint is reached, and the drilling operation is completed; and obtain the borehole transient electromagnetic detection data.

6. The method according to claim 5, wherein the water inrush is detected in real time by using the transient electromagnetic method. The borehole transient electromagnetic detection data in step 4 includes data of resistivity changing with time and depth, wherein the resistivity is obtained by the following formula: wherein p s represents the resistivity; μ0 represents the vacuum permeability; s represents the receiving coil area; n represents the receiving coil turns; S represents the transmitting coil area; N represents the receiving coil turns; wherein the transmitting coil and the receiving coil are both rotating coils (6), s=S; n=N; t represents the real-time time at the time of observation; V represents the voltage of the rotating coil (6) at the time of observation; I represents the current of the rotating coil (6) at the time of observation; C represents an adjustment coefficient, which is related to the lithology of the measurement point.

7. The method according to claim 6, wherein the water inrush is detected in real time by using the transient electromagnetic method. The depth corresponding to the resistivity at a certain time in step 4 is obtained by the following steps: Step a, using the following formula, the calculation depth corresponding to the detection depth at each time is obtained: wherein h i represents the calculated depth corresponding to the detection depth at the i-th time point; t i denotes the time of observation corresponding to the i-th time instant; ρ i represents the resistivity corresponding to the i-th moment; σ represents the reciprocal of the resistivity corresponding to the i-th time; Step b, using the formula, actual depth H at each instant of time i : wherein K represents the full-space coefficient.

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