Drilling hole bottom transient electromagnetic water disaster real-time detection device and method

Abstract

The invention discloses a real-time detection device for transient electromagnetic water disasters at the bottom of a drill hole, which is characterized in that hidden water disasters in a certain radial range at the bottom of the drill hole are explored in a manner that a rotating coil is pushed by hydraulic power, and connection with the detection device can be realized by using conventional methods such as a hole bottom relay and a signal transmission line in a cable-passing drill rod. Real-time transmission of hole bottom data is achieved, timeliness guidance is provided for drilling, and the defects that the workload of secondary pushing is increased and timeliness is not enough are overcome. And meanwhile, a charging and power supply assembly driven by a hydroelectric power generation principle is arranged in the detection device, so that the operation of a rotary emission rotating coil can be continuously supported in a manner of supplying power to equipment under long-time use, charging two independent batteries and periodically switching power supply, the limitation of the electric quantity of the batteries is broken through, and a guarantee is provided for real-time detection.

Description

Technical Field

[0001] The invention belongs to the field of geophysical exploration, and in particular relates to a device and method for real-time detection of transient electromagnetic water hazards at the bottom of a borehole. Background Art

[0002] Coal mine water hazard accident detection is an important part of daily work, usually carried out before excavation / mining, through conventional geophysical exploration means or advance drilling, and detection in the borehole to achieve the purpose of early detection of water hazards / structures. In the field of advanced exploration of coal mine geological hazards / water hazards, the exploration work is basically independent, that is, it is carried out while other processes are completed or waiting.

[0003] In the past, various methods of advance detection of water hazards generally had an advance detection distance of less than 100m. The original detection distance is far from meeting the requirements. If the detection distance or detection mode is not changed, in order to meet safety requirements, the detection work must be carried out at a frequency of once every 1-2 days, which will undoubtedly lead to stagnation of excavation and impose a heavy burden on the detection construction personnel, which is unacceptable for an efficiently operating mine.

[0004] Various types of geophysical exploration data underground are currently still in the state of self-storage and partial data access to the ring network. It is still impossible to achieve the purpose of seamless connection between exploration results and drilling / excavation construction and guide drilling. In particular, there is still a large gap between the results of water hazard exploration in the borehole and the goals of guiding drilling direction, revealing structures, and early warning of water hazards. There is a general problem that it is impossible to conduct an all-round exploration of the bottom of the hole, it is impossible to solve the problem of long-term power supply of the equipment at the bottom of the hole, and it is difficult to transmit the data from the bottom of the borehole to the hole mouth, so it is impossible to meet the needs of dynamic real-time transmission, continuous processing, and timely feedback. Summary of the invention

[0005] The purpose of the present invention is to provide a device and method for real-time detection of transient electromagnetic water hazards at the bottom of a borehole, so as to solve the problem that the bottom water hazard detection device in the prior art cannot meet the requirements of dynamic real-time transmission, continuous processing and timely feedback.

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

[0007] A real-time detection device for transient electromagnetic water damage at the bottom of a borehole, comprising a drill bit, a drill rod connected to the rear of the drill bit, a detection device connected to the rear of the drill rod, the detection device being in a tubular shape with the same specifications as the drill rod, and the rear of the detection device being able to sequentially connect multiple drill rods;

[0008] A launching tube is coaxially fixedly arranged in the middle of the detection device, and an annular space is provided between the launching tube and the detection device to form a water passage; a power generating blade is coaxially rotatedly arranged in the front of the detection device;

[0009] A rotating shaft is coaxially and rotatably inserted into the detection device, and an attitude measurement device, a rotating coil, a rotating damper and a rotating blade are sequentially arranged on the rotating shaft from front to back; the attitude measurement device and the rotating coil are located inside the launch tube, and the rotating damper and the rotating blade are located at the rear of the launch tube;

[0010] A charging and power supply assembly is also provided inside the transmitting tube, and the charging and power supply assembly includes a rechargeable 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 them to a receiver;

[0012] The controller is used to control the transmitting current in the rotating coil, thereby switching the transmitting and receiving states of the rotating coil;

[0013] The output end of the power generating blade is connected to the rechargeable battery to supply power to the rechargeable battery;

[0014] The rechargeable battery is used to supply power to the rotating coil, the controller, the wireless transmitter and the receiver after the power supply battery is exhausted;

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

[0016] The receiver is used to receive 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] Furthermore, the detection device is a non-metallic drill rod.

[0019] Furthermore, the detection device is fixedly connected to the transmitting tube via an inner tube support ring.

[0020] Furthermore, it also includes a generator, the power generation blades are connected to the input end of the generator, and the output end of the generator is connected to the rechargeable battery.

[0021] A method for real-time detection of transient electromagnetic water damage at the bottom of a borehole, based on the above-mentioned device for real-time detection of transient electromagnetic water damage at the bottom of a borehole, comprises the following steps:

[0022] Step 1, determine the area to be drilled, and design the original drilling trajectory and drilling end point in the area to be explored;

[0023] Step 2, drilling is carried out according to the original drilling trajectory, after the first drill rod is lowered, the detection device is connected to the rear of the first drill rod; another drill rod is connected to the rear of the detection device to continue drilling;

[0024] Step 3: Use a detection device to perform real-time transient electromagnetic detection in the hole until the drill rod connected this time completely enters the borehole, completing the drilling;

[0025] Step 4: The external wireless receiving device receives the voltage and current data detected by the detection device during 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 voltage data, and then determines whether the drilling trajectory needs to be adjusted;

[0026] If yes, redesign the drilling trajectory, connect another drill rod to the rear of the previous drill rod, and drill according to the redesigned drilling trajectory;

[0027] If not, connect another drill rod to the rear of the previous drill rod and continue drilling according to the most recently designed drilling trajectory;

[0028] Step 5, repeat steps 3-4 until reaching the drilling end point and completing the drilling operation; obtain transient electromagnetic detection data in the hole.

[0029] Furthermore, the transient electromagnetic detection data in the hole in step 4 includes data on the change of resistivity with time and depth, wherein the resistivity is obtained by the following formula:

[0030]

[0031] Among them, ρ s represents resistivity;

[0032] μ 0 represents the magnetic permeability of vacuum;

[0033] s represents the receiving coil area;

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

[0038] t represents the real time of observation;

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

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

[0041] C represents the adjustment coefficient, which is related to the lithology of the measurement point.

[0042] Furthermore, the depth corresponding to the resistivity in step 4 at a certain moment is obtained by the following steps:

[0043] Step a, use the following formula to obtain the calculated depth corresponding to the detection depth at each moment:

[0044]

[0045] Among them, h i Indicates the calculated depth corresponding to the detection depth at the i-th moment;

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

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

[0048] σ represents the inverse of the resistivity corresponding to the i-th moment;

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

[0050]

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

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

[0053] (I) The instantaneous electromagnetic water hazard real-time detection device for the bottom of a borehole of the present invention uses hydraulic power to drive a rotating coil to detect hidden water hazards within a certain radial range at the bottom of the borehole. Conventional methods such as a bottom hole relay and a cable drill pipe internal signal transmission line can be used to connect with the detection device, realize real-time transmission of bottom hole data, provide timely guidance for drilling, and overcome the drawbacks of increased secondary push workload and insufficient timeliness.

[0054] At the same time, a charging and power supply component driven by the principle of hydroelectric power generation is set up inside the detection device, which can meet the power supply needs of the equipment under long-term use. The two independent batteries are charged and the power supply is periodically switched to continuously support the operation of the rotating transmitting coil, breaking through the battery power limit and providing guarantee for real-time detection.

[0055] (II) The method for real-time detection of water hazards at the bottom of a borehole using transient electromagnetic technology of the present invention discloses a method for calculating resistivity and depth. The above method can be used to obtain the law of resistivity variation with time and radial depth of the borehole, thereby providing a favorable theoretical basis for judging whether there is water hazard in the drilling area, providing data support for advance detection of water hazard, and being suitable for large-scale use and promotion in industry. BRIEF DESCRIPTION OF THE DRAWINGS

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

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

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

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

[0060] Figure 5 It is a schematic diagram showing the variation of the induced voltage of the rotating coil with time in one embodiment of the present invention.

[0061] The meaning of the symbols in the figure is:

[0062] 1. Detection device; 2. Launch tube; 3. Power generating blades; 4. Rotating shaft; 5. Attitude measurement device; 6. Rotating coil; 7. Rotating damper; 8. Rotating blades; 9. Charging and power supply assembly; 10. Inner tube support ring; 11. Generator. DETAILED DESCRIPTION

[0063] It should be noted that, unless otherwise specified, all components in the present invention are components known in the prior art. For example, the rotary damper is a known and commonly used rotary damper.

[0064] Specific embodiments of the present invention are given below. It should be noted that the present invention is not limited to the following specific embodiments, and all equivalent changes made on the basis of the technical solution of this application fall within the protection scope of the present invention.

[0065] like Figure 1-3 As shown, a real-time detection device for transient electromagnetic water damage at the bottom of a borehole comprises a drill bit, a drill rod is connected to the rear of the drill bit, a detection device 1 is connected to the rear of the drill rod, and the detection device 1 is a tubular shape with the same specifications as the drill rod. The rear of the detection device 1 can be connected to multiple drill rods in sequence;

[0066] A launch tube 2 is coaxially and fixedly arranged in the middle of the detection device 1, and an annular space is between the launch tube 2 and the detection device 1 to form a water passage; a power generation blade 3 is coaxially and rotatably arranged in the front of the detection device 1;

[0067] A rotating shaft 4 is coaxially inserted into the detection device 1, and an attitude measurement device 5, a rotating coil 6, a rotating damper 7 and a rotating blade 8 are arranged on the rotating shaft 4 in sequence from front to back; the attitude measurement 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] A charging and power supply component 9 is also provided inside the transmitting tube 2, and the charging and power supply component 9 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 them 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 generating 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 exhausted;

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

[0074] The receiver is used to receive the 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, in order to ensure the continuous operation of the transient electromagnetic at the bottom of the hole, the battery is continuously charged by the self-generated electricity at the bottom of the hole, and the charging and power supply component 9 can adopt the commonly used charging and power supply circuit known in the prior art;

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

[0078] Among them, both the rechargeable battery and the power supply battery are provided with a double-throw switch. According to conventional selection, the switch is used to control whether the battery is in a power supply state or a charging state. A control switch is installed on the charging circuit. During the drilling process, the hydraulic power drives the power generation blade 3 to rotate and generate electricity to supply power to the rechargeable battery. A control switch is installed on the rechargeable battery circuit. When the battery voltage reaches or exceeds the set value, the control switch in the circuit will be disconnected, and the rechargeable battery and the power supply battery will switch with each other. The rechargeable battery switches with the power supply battery after the power supply battery is exhausted, and the original power supply battery is charged.

[0079] The control switch adopts a known existing control switch, and the control switch and other components are controlled by known existing algorithms. Other components not specifically described are known existing components, such as the wireless transmitter is selected according to the conventional method, and a Bluetooth short transmission device can be used.

[0080] Figure 4 A schematic diagram of the principle of radial measurement is given, in which the transmitting rotating coil and the receiving rotating coil are the same rotating coil. During the drilling process, the rotating coil rotates periodically around the rotating axis to achieve full-range scanning of the borehole radial direction.

[0081] During the power supply phase, a constant current with a strength of I flows through the rotating coil, and the current generates a stable magnetic field H0 in space. 1 At this moment, the current in the rotating coil disappears. According to Faraday's law of electromagnetic induction, the magnetic field distributed in the space will not disappear immediately. Eddy currents will be generated in the stratum to maintain the existence of the original magnetic field. The magnetic field generated by the eddy current is the secondary field H1.

[0082] At different times after power failure, the depth, radius and intensity of the equivalent eddy current will gradually change. Correspondingly, the secondary magnetic field will also change with time and gradually decay. The magnetic field induces a voltage in the receiving rotating coil and is received by the equipment in the hole. By recording the magnitude of the induced secondary voltage at different times in the transmitting direction, the change of resistivity in this direction with depth can be obtained.

[0083] By rotating the coil to detect in one direction, the resistivity change within a certain distance in that direction can be obtained. By detecting at multiple angles at a point, the resistivity change with depth within a 360-degree range at the measuring point can be obtained, thereby achieving the purpose of all-round exploration of hidden water bodies within a certain range beside the borehole.

[0084] Due to the need for radial 360° exploration, the rotating coil needs to be constantly rotated to adjust the launch direction. In actual coal seam drilling projects, the drill rod does not rotate as a whole, but the drill bit itself is driven by hydraulic power to achieve the purpose of rock breaking. Under the premise that the drill rod does not move, in order to adjust the detection direction, the launch rotating coil must rely on its own power. In order to solve the problem of the launch rotating coil rotating,

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

[0086] This embodiment adopts a high-pressure perforating water flow coaxial drive mode, that is, the high-pressure water column drives the rotating blade 8 to rotate, and the rotating blade 8 drives the coaxial transmitting rotating coil to rotate. The high-speed water flow drives the rotating blade 8 to rotate. According to the water pressure of the high-speed water flow column, the rotating damper 7 configures a suitable rotation damping for the rotating blade 8, drives the rotating coil to rotate at the actual required speed cycle, and at the same time installs a posture measurement device on the rotating shaft 4 to measure the real-time exploration direction.

[0087] The posture measurement device is a commonly used device known in the prior art, and specifically, a rolling angle measurement device may be used.

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

[0089] As a preferred solution, the detection device 1 is fixedly connected to the launch tube 2 via the inner tube support ring 10, thereby strengthening the connection strength between the detection device 1 and the launch tube 2.

[0090] As a preferred solution, the power generation blades 3 are connected to the input end of the generator 11, and the output end of the generator 11 is connected to the rechargeable battery. The power generation blades 3 drive the generator 11 to generate electricity, and then supply power to the charging and supplying assembly 9.

[0091] This embodiment uses hydraulic drive to rotate the rotating coil to detect hidden water hazards within a certain radial range at the bottom of the borehole, and uses hydraulic drive to continuously charge the rechargeable battery at the bottom of the hole, thereby achieving the goal of long-term, all-round and real-time detection. Compared with the prior art, the method proposed in this embodiment has the following advantages:

[0092] First of all, the current traditional in-hole transient electromagnetic method adopts a secondary push mode, that is, after the drilling construction work is completed, the in-hole transient electromagnetic probe is pushed into the borehole for exploration. After the exploration is completed, the probe tube is taken out and the data in the probe tube is exported. The data is analyzed to obtain the distribution of hidden water hazards within a certain radial range of the entire borehole section.

[0093] In this exploration mode, the exploration process is separated from the drilling process, and the acquisition of the borehole radial water hazard distribution results lags far behind the drilling construction process, and cannot provide effective guidance for the drilling process. The method of this embodiment can seamlessly combine the drilling process with the exploration process, realize exploration while drilling, and adjust at any time, which greatly enhances the timeliness of the detection effect.

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

[0095] A method for real-time detection of transient electromagnetic water damage at the bottom of a borehole, the device for real-time detection of transient electromagnetic water damage at the bottom of a borehole comprises the following steps:

[0096] Step 1, determine the area to be drilled, and design the original drilling trajectory and drilling end point in the area to be explored;

[0097] Step 2, drilling is carried out according to the original drilling trajectory, after the first drill rod is lowered, the detection device 1 is connected to the rear of the first drill rod; another drill rod is connected to the rear of the detection device 1 to continue drilling;

[0098] Step 3, using the detection device 1 to perform real-time transient electromagnetic detection in the hole; until the drill rod connected this time completely enters the borehole, completing the drilling;

[0099] Specifically, during the drilling process, the high-pressure water flow in the borehole has three functions:

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

[0101] 2. Drive the transmitting coil to rotate continuously to realize the exploration of different radial angles of the borehole

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

[0103] According to conventional selection in the field, 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 pipe (usually 2-3m), the tail end of the drill pipe is removed, and a signal receiver is used to connect the cable signal line inside the drill pipe. The signal stored in the relay is transmitted to the signal receiver through the cable signal line;

[0104] Step 4: The external wireless receiving device receives the voltage data detected by the detection device 1 during the 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 determines whether the drilling trajectory needs to be adjusted;

[0105] If yes, redesign the drilling trajectory, connect another drill rod to the rear of the previous drill rod, and drill according to the redesigned drilling trajectory;

[0106] If not, connect another drill rod to the rear of the previous drill rod and continue drilling according to the most recently designed drilling trajectory;

[0107] Specifically, after receiving the data, the ground server can use known and commonly used automated data processing programs to process the data and automatically generate an exploration report, and determine the next drilling construction process based on the exploration report; technical personnel in this field can also make judgments.

[0108] Among them, after a data transmission is completed, the connection between the hole mouth signal receiver and the cable signal line inside the drill pipe is disconnected, a drill pipe is connected to the tail end of the drill pipe, and the tail end pumping device is connected to the tail end of the new drill pipe again. The high-pressure water flow continues to drive the drill bit to break the rock and the transmitting coil to rotate to collect data and charge the rechargeable battery at the same time.

[0109] Step 5, repeat steps 3-4 until the drilling end point is reached and the drilling operation is completed; obtain transient electromagnetic detection data in all holes. Based on the obtained borehole transient electromagnetic data, real-time detection of water damage at the bottom of the hole can be achieved, and the electrical changes of the rock formation within a certain radial range at the bottom of the borehole can be continuously revealed during the drilling process, providing timely guidance for drilling.

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

[0111]

[0112] Among them, ρ s represents resistivity;

[0113] μ 0 represents the magnetic permeability of vacuum;

[0114] s represents the area of ​​the receiving rotating coil;

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

[0116] S represents the area of ​​the transmitting rotating coil;

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

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

[0119] t represents the real time of observation;

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

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

[0122] C represents the adjustment coefficient, which is related to the lithology of the measurement point. The technical personnel in this field determine the adjustment coefficient based on the actual local geological conditions.

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

[0124] Step a, use the following formula to obtain the calculated depth corresponding to the detection depth at each moment:

[0125]

[0126] Among them, h i Indicates the calculated depth corresponding to the detection depth at the i-th moment;

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

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

[0129] σ represents the inverse 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, the calculated depth can be considered to be the distance of the double path of the electromagnetic wave, so half of the depth needs to be subtracted. Using the following formula, the actual depth H at each moment is i :

[0131]

[0132] Wherein, K represents the full space coefficient. The full space coefficient K varies with different detection environments and is generally obtained through experience or experimental means. Those skilled in the art are capable of confirming the value of the full space coefficient K according to actual conditions.

Claims

1. A real-time detection device for transient electromagnetic water damage at the bottom of a borehole, comprising a drill bit, characterized in that: The rear of the drill bit is connected to a drill rod, and the rear of the drill rod is connected to a detection device (1). The detection device (1) is a tube with the same specifications as the drill rod, and the rear of the detection device (1) can be connected to multiple drill rods in sequence; A launching tube (2) is coaxially fixedly arranged in the middle of the detection device (1), and an annular space exists between the launching tube (2) and the detection device (1), forming a water passage; a power generation blade (3) is coaxially rotatably arranged in the front of the detection device (1); A rotating shaft (4) is coaxially and rotatably inserted into the detection device (1), and an attitude measurement device (5), a rotating coil (6), a rotating damper (7) and a rotating blade (8) are sequentially arranged on the rotating shaft (4) from front to back; the attitude measurement 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); A charging and power supply component (9) is also arranged inside the transmitting tube (2), and the charging and power supply component (9) comprises a rechargeable battery, a power supply battery, a controller, a wireless transmitter and a receiver; The rotating coil (6) is used to transmit and receive voltage and current data and transmit them to a receiver; 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); The output end of the power generating blade (3) is connected to a rechargeable battery to supply power to the rechargeable battery; 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 exhausted; The power supply battery is used to supply power to the rotating coil, the controller, the wireless transmitter and the receiver; The receiver is used to receive data transmitted by the rotating coil (6) and transmit it to the wireless transmitter; The wireless transmitter is used to transmit the received information to an external wireless receiving device.

2. The device for real-time detection of transient electromagnetic water damage at the bottom of a borehole according to claim 1, characterized in that: The detection device (1) is a non-metallic drill rod.

3. The device for real-time detection of transient electromagnetic water damage at the bottom of a borehole according to claim 2, characterized in that: The detection device (1) is fixedly connected to the transmitting tube (2) via an inner tube support ring (10).

4. The device for real-time detection of transient electromagnetic water damage at the bottom of a borehole according to claim 3, characterized in that: It also comprises a generator (11), the power generating blades (3) are connected to the input end of the generator (11), and the output end of the generator (11) is connected to a rechargeable battery.

5. A method for real-time detection of transient electromagnetic water damage at the bottom of a borehole, the method being based on the device for real-time detection of transient electromagnetic water damage at the bottom of a borehole as claimed in claim 4, characterized in that: The following steps are involved: Step 1, determine the area to be drilled, and design the original drilling trajectory and drilling end point in the area to be explored; Step 2, drilling is carried out according to the original drilling trajectory, after the first drill rod is lowered, the detection device (1) is connected to the rear of the first drill rod; another drill rod is connected to the rear of the detection device (1) to continue drilling; Step 3, using the detection device (1) to perform real-time transient electromagnetic detection in the hole until the drill rod connected this time completely enters the borehole, thus completing the drilling; Step 4: an external wireless receiving device receives the voltage and current data detected by the detection device (1) during the drilling and transmits it to the ground server. The ground server obtains transient electromagnetic detection data in the hole based on the received voltage data, and then determines whether the drilling trajectory needs to be adjusted. If yes, redesign the drilling trajectory, connect another drill rod to the rear of the previous drill rod, and drill according to the redesigned drilling trajectory; If not, connect another drill rod to the rear of the previous drill rod and continue drilling according to the most recently designed drilling trajectory; Step 5, repeat steps 3-4 until reaching the drilling end point and completing the drilling operation; obtain transient electromagnetic detection data in the hole.

6. The method for real-time detection of transient electromagnetic water damage at the bottom of a borehole according to claim 5, characterized in that: The transient electromagnetic detection data in the hole in step 4 includes data on the change of resistivity with time and depth, wherein the resistivity is obtained by the following formula: Among them, ρ s represents resistivity; μ0 represents the magnetic permeability of vacuum; s represents the receiving coil area; n represents the number of turns of the receiving coil; S represents the area of ​​the transmitting coil; N represents the number of turns of the receiving coil; Wherein, the transmitting coil and the receiving coil are both rotating coils (6), s=S; n=N; t represents the real time of observation; V represents the voltage of the rotating coil (6) during observation; I represents the current of the rotating coil (6) during observation; C represents the adjustment coefficient, which is related to the lithology of the measurement point.

7. The method for real-time detection of transient electromagnetic water damage at the bottom of a borehole according to claim 6, characterized in that: The depth corresponding to the resistivity in step 4 at a certain moment is obtained by the following steps: Step a, use the following formula to obtain the calculated depth corresponding to the detection depth at each moment: Among them, h i Indicates the calculated depth corresponding to the detection depth at the i-th moment; t i represents the observation time corresponding to the i-th moment; ρ i represents the resistivity corresponding to the i-th moment; σ represents the inverse of the resistivity corresponding to the i-th moment; Step b, use the following formula, the actual depth H at each moment i : Wherein, K represents the full space coefficient.

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