Power supply nipple of logging-while-drilling instrument

Abstract

The invention discloses a power supply short section of a logging while drilling instrument, which is used for miniaturization of an LWD (Logging While Drilling) and comprises a battery module based on a booster circuit, and from the perspective of power supply, the booster circuit is adopted to replace part of batteries, so that the purpose of reducing the space required by the battery module and further realizing miniaturization of the LWD is achieved. The number of batteries required by the battery module can be reduced to a great extent, so that the purpose of saving space is achieved; meanwhile, the formed parallel oscillation circuit also has the effects of stabilizing the output voltage, improving the power factor of the whole system, reducing the apparent power demand of the power supply and protecting the circuit.

Description

Technical Field

[0001] The present invention belongs to the technical field of logging while drilling instruments, and particularly relates to a power supply sub-section for a logging while drilling instrument comprising a battery module based on a boost circuit. Background Art

[0002] A logging while drilling (LWD) instrument is a real-time measurement system integrated in a drilling tool, which can synchronously obtain downhole geological and engineering parameters during the drilling process of the drill bit, significantly improving the efficiency and safety of oil and gas exploration and development. LWD instruments are usually integrated inside or below the drill collar, close to the drill bit. This layout can reduce the interference of drilling fluid on measurement data, such as obtaining more accurate formation information before mud invades the formation. The drill collar, as an important part of the drill string, provides mechanical support and protection for the LWD, preventing the instrument from being damaged due to vibration or high pressure. In horizontal wells or complex wellbore trajectories, the LWD cooperates with a directional drill collar (with a bent sub or rotary steerable system) to adjust the tool face angle in real time to ensure that the wellbore trajectory meets the design requirements.

[0003] With the development of technology, more and more LWDs adopt battery power supply to improve operation flexibility and safety. However, battery power supply will increase the length of the drill collar. The drill collar is a part of the drill string, which is used to stabilize the drill bit and transmit torque, and its length directly affects the flexibility of drilling operations. A longer drill collar will make the drill string more cumbersome and difficult to turn flexibly in complex formations. Especially during directional drilling and horizontal drilling, the length of the drill collar is crucial for the build-up performance (i.e., the ability to change the wellbore trajectory). A shorter drill collar can more precisely control the direction of the drill bit, improve the build-up rate, and thus better adapt to changes in geological conditions and achieve more precise wellbore trajectory control.

[0004] The length of the drill collar also affects other key performance indicators of drilling operations. For example: 1. A longer drill collar increases the total weight and friction of the drill string, which may lead to power loss of the rig, reducing the drilling speed and efficiency; 2. An overly long drill collar may affect the stability of the tool face (i.e., the measuring instruments and tools installed on the drill collar), resulting in inaccurate measurement data and affecting the scientific nature of decision-making; 3. A longer drill collar increases the overall complexity of the drill string, which may lead to more mechanical failure points, increasing the maintenance cost and operation risk. Therefore, for the LWD attached to the drill collar, it also needs to be miniaturized. Summary of the Invention

[0005] In response to the need for miniaturization of LWD, from the perspective of power supply, the present invention proposes a boost circuit for DC-to-AC conversion, a battery module based on it, and an LWD power supply sub-section comprising this battery module, aiming to reduce the space required for the battery module and thus achieve the miniaturization of LWD.

[0006] A power supply sub-section for a logging-while-drilling instrument, comprising a battery module removably fixed on a circuit framework and a circuit module. The circuit module includes a boost circuit for converting direct current to alternating current.

[0007] The boost circuit includes two groups of twin circuits. Each group of twin circuits includes a first switch branch, a voltage-dividing branch, a charge-discharge branch, and a second switch branch connected in parallel. The two ends of these four branches are respectively connected to the positive and negative electrodes of the battery pack. Both the first and second switch branches include two switches connected in series and not closed simultaneously. The connection point of the two switches in the first switch branch is also connected to the negative electrode of the battery pack through a current-limiting resistor. The simplest form of the first and second charge-discharge branches here is a capacitor, and the simplest form of the voltage-dividing branch is a resistor.

[0008] The output voltage of the boost circuit is taken from the connection points of the two switches in the second switch branch of the two groups of twin circuits. By controlling the opening and closing states of the four switches in the two groups of twin circuits, the two charge-discharge branches are made to present different states of charging, energy storage, and discharging. When the charge-discharge branch is in the discharging state, it is superimposed with the battery pack voltage and output to the connection points of the respective second switch branches in parallel, thereby realizing the boost output of converting direct current to alternating current.

[0009] In terms of structure:

[0010] As an alternative solution of the present invention, at least one battery installation groove and at least one circuit installation groove are provided on the outer periphery of the circuit framework to isolate the battery module from the circuit module.

[0011] As an alternative solution of the present invention, a battery cover plate is removably fixed along the battery installation groove on the circuit framework. The battery cover plate and the battery installation groove form a clamping fixation for the battery module.

[0012] As an alternative solution of the present invention, a wire groove is provided at one end of the battery installation groove. The electrode leads of the battery module pass through the wire groove and are connected to a plug connector fixed on the circuit framework.

[0013] As an alternative solution of the present invention, the circuit module is fixed in the circuit installation groove and includes a cover, a support member for supporting the cover, and a printed circuit board fixed below the cover.

[0014] As an alternative solution of the present invention, a plurality of holes are provided on the cover.

[0015] As an alternative solution of the present invention, a through hole serving as a mud channel is provided through the interior of the circuit framework.

[0016] In terms of circuit:

[0017] As an alternative solution of the present invention, the two groups of twin circuits are respectively the first and second twin circuits. The charge and discharge branch of the first twin circuit is denoted as the first charge and discharge branch, and the charge and discharge branch of the second twin circuit is denoted as the second charge and discharge branch. The two ends of the output voltage of the boost circuit are respectively denoted as TK+ and TK-, where TK+ is taken from the first twin circuit and TK- is taken from the second twin circuit;

[0018] The positive pole of the battery pack is connected to the voltage dividing branch, the charge and discharge branch, and the second switch branch through a diode; the first switch branch of the first twin circuit includes a first switch and a second switch connected in series, and the second switch branch of the first twin circuit includes a third switch and a fourth switch connected in series; the first switch branch of the second twin circuit includes a seventh switch and an eighth switch connected in series, and the second switch branch of the second twin circuit includes a fifth switch and a sixth switch connected in series;

[0019] The boost circuit operates in the following eight different stages and presents five different states:

[0020] L1, all the first to eighth switches are off, and the battery pack charges the first and second charge and discharge branches respectively;

[0021] L2, the first and eighth switches are on, and the rest of the switches are off. Since the first switch is closed and with the unidirectional conductivity of the diode, the first charge and discharge branch is in the energy storage state, and the second charge and discharge branch is still in the charging state;

[0022] L3, the first, third, sixth, and eighth switches are on, and the rest of the switches are off. Since the third and sixth switches are on, the first charge and discharge branch discharges to the TK+ terminal and is superimposed with the positive voltage of the battery pack. At this time, the second charge and discharge branch is still in the charging state;

[0023] L4, the first and eighth switches are on, and the rest of the switches are off, that is, it returns to the state of L2;

[0024] L5, all the first to eighth switches are off, that is, it returns to the state of L1;

[0025] L6, the second and seventh switches are on, and the rest of the switches are off. Since the seventh switch is on and with the unidirectional conductivity of the diode, the second charge and discharge branch is in the energy storage state, and the first charge and discharge branch is still in the charging state;

[0026] L7, the second, fourth, fifth, and seventh switches are on, and the rest of the switches are off. Since the fourth and seventh switches are on, the second charge and discharge branch discharges to the TK- terminal and is superimposed with the positive voltage of the battery pack. At this time, the first charge and discharge branch is still in the charging state;

[0027] L8, the second and seventh switches are on, and the rest of the switches are off, that is, it returns to the state of L6.

[0028] As an alternative embodiment of the present invention, a MOS transistor is used as the switch, and the entire circuit is constructed in the form of an integrated circuit.

[0029] The present invention provides a boost circuit for converting direct current to alternating current, a battery module based thereon, and an LWD power supply sub-section including the battery module, which can significantly reduce the number of battery cells required for the battery module, thereby achieving the purpose of saving space; at the same time, the formed parallel oscillation circuit also has the functions of stabilizing the output voltage, improving the power factor of the entire system, reducing the apparent power demand of the power supply, and protecting the circuit. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 is a three-dimensional structure diagram of the power supply sub-section disclosed in the present invention;

[0031] Figure 2 is a radial cross-sectional view of the power supply sub-section disclosed in the present invention;

[0032] Figure 3 is a three-dimensional structure diagram of the circuit framework disclosed in the present invention;

[0033] Figure 4 is a planar structure diagram of the circuit framework disclosed in the present invention;

[0034] Figure 5 is the boost circuit diagram for converting direct current to alternating current disclosed in the present invention and its state one;

[0035] Figure 6 is the timing control logic of the boost circuit for converting direct current to alternating current disclosed in the present invention;

[0036] Figure 7 is the state two of the boost circuit diagram for converting direct current to alternating current disclosed in the present invention;

[0037] Figure 8 is the state three of the boost circuit diagram for converting direct current to alternating current disclosed in the present invention;

[0038] Figure 9 is the state four of the boost circuit diagram for converting direct current to alternating current disclosed in the present invention;

[0039] Figure 10 is the state five of the boost circuit diagram for converting direct current to alternating current disclosed in the present invention;

[0040] Figure 11 is a resistance value configuration scheme of the boost circuit diagram for converting direct current to alternating current disclosed in the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0041] The present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments. The embodiments of the present invention are given for the purpose of illustration and description, and are not exhaustive or limited to the disclosed form. Many modifications and variations are obvious to those of ordinary skill in the art. The embodiments are selected and described to better illustrate the principles and practical applications of the present invention, and to enable those of ordinary skill in the art to understand the present invention and thus design various embodiments with various modifications suitable for specific purposes.

[0042] In order to adapt to complex downhole environments, improve functional flexibility and reliability, and at the same time meet the requirements of efficient operations in oil and gas exploration and development, LWD mainly adopts a short-section structural design. As the basic component unit of LWD, a short section is usually a segmented structure composed of multiple functional modules (such as gamma, resistivity, nuclear magnetic resonance, etc.) connected by threads. Each short section is independently encapsulated and can be replaced or upgraded individually, forming a modular and expandable logging tool string. Starting from the power supply perspective, the present invention uses a boost circuit to replace some batteries, achieving the purpose of reducing the space required for the battery module and thus realizing the miniaturization of LWD.

[0043] A power supply short section of a logging-while-drilling instrument, as Figures 1-4 shown, includes a battery module 200 and a circuit module 300 detachably fixed on a circuit skeleton 100. The circuit module 300 includes a boost circuit for converting direct current to alternating current. A through hole 105 serving as a mud channel is disposed through the interior of the circuit skeleton 100. It should be noted that only the middle region of the circuit skeleton 100 is the power supply short section, and the upper and lower short sections for connecting communication units are provided at both ends, which are not the content involved in the present invention and will not be elaborated herein.

[0044] The boost circuit includes two sets of twin circuits. Each set of twin circuits includes a first switch branch, a voltage dividing branch, a charge-discharge branch, and a second switch branch connected in parallel. The two ends of these four branches are respectively connected to the positive and negative electrodes of the battery pack; both the first and second switch branches include two switches connected in series and not closed simultaneously. The connection point of the two switches in the first switch branch is also connected to the negative electrode of the battery pack through a current-limiting resistor;

[0045] The output voltage of the boost circuit is taken from the connection points of the two switches in the second switch branches of the two sets of twin circuits. By controlling the opening and closing states of the four switches in the two sets of twin circuits, the two charge-discharge branches are made to exhibit different states of charging, energy storage, and discharging; when the charge-discharge branch is in the discharging state, it is superimposed with the battery pack voltage and output to the connection points of the respective parallel second switch branches, thereby realizing the boost output of converting direct current to alternating current.

[0046] For the convenience of description, Figure 5A specific form of the boost circuit for DC - to - AC conversion disclosed by the present invention is given. The upper part is the first twin circuit, and the lower part is the second twin circuit. The first and second twin circuits form a parallel oscillation circuit connected in parallel between TK+ and TK-.

[0047] Combined with Figure 5 , the first switch branch of the first twin branch includes the first switch Q1 and the second switch Q2, and the second switch branch of the first twin branch includes the third switch Q3 and the fourth switch Q4; the first switch branch of the second twin branch includes the fifth switch Q5 and the sixth switch Q5, and the second switch branch of the second twin branch includes the seventh switch Q7 and the eighth switch Q8.

[0048] The first charge - discharge branch is the capacitor C3, and the second charge - discharge branch is the capacitor C6.

[0049] The core purpose of this embodiment is to make the two charge - discharge branches present different states of charging, energy storage, and discharging by controlling the opening and closing states of the four switches in the two groups of twin circuits; when the charge - discharge branch is in the discharging state, it is respectively superimposed with the battery - pack voltage and output to the connection points of the second switch branches connected in parallel to each other, so as to achieve the boost output of DC - to - AC conversion.

[0050] To achieve the above - mentioned purpose, the timing control of the switches Q1~Q8 is as Figure 6 shown. Under this timing control logic, the boost circuit works in the following eight different stages L1~L8 and presents five different states.

[0051] L1, Q1~Q8 are all off. Refer to Figure 5 , which is called state one.

[0052] Since Q3, Q4, Q7, and Q8 are all off, there is no connection relationship between TK+ and TK - and the two groups of twin circuits. The two ends of the capacitor C3 are respectively connected to the positive pole HV+ and the negative pole HV - of the battery pack through A and B, and the two ends of the capacitor C6 are respectively connected to the positive pole HV+ and the negative pole HV - of the battery pack through C and D. Thus, in this state, the battery pack charges the capacitor C3 and the capacitor C6 respectively. The red arrow indicates the current flow direction of the battery pack, and the same applies hereinafter.

[0053] L2, Q1 and Q8 are on, and the rest of the switches are off. Refer to Figure 7 , which is called state two.

[0054] Since Q1 is on, the voltage - dividing branch is short - circuited, and the current flow direction of the first twin circuit is as shown by the upper red arrow in Figure 7 . Plus the unidirectional conductivity of the diode, the capacitor C3 is in the energy - storage state; since Q8 is closed, the current - limiting resistor is short - circuited, and the current flow direction of the second twin circuit is as shown by the lower red arrow in Figure 7 , and the capacitor C6 is still in the charging state.

[0055] In L3, Q1, Q8, Q3, and Q6 are turned on, and the rest of the switches are turned off. Refer to Figure 8 , which is called State Three.

[0056] Since Q1 and Q3 are turned on simultaneously, capacitor C3 discharges to the TK+ terminal, which is superimposed on the positive voltage of the battery pack, making the voltage at the TK+ terminal the sum of the positive voltage of the battery pack and the discharge voltage of capacitor C3. The current flow direction between TK+ and HV+ is as Figure 8 shown by the upper green arrow; in coordination with Q6 and Q8 being turned on simultaneously, the current flow direction between TK- and HV- is as Figure 8 shown by the lower red arrow. At this time, capacitor C6 is still in the charging state.

[0057] In L4, switches Q1 and Q8 are turned on, and the rest of the switches are turned off, that is, it returns to State Two.

[0058] In L5, Q1 - Q8 are all turned off, that is, it returns to State One.

[0059] In L6, Q2 and Q7 are turned on, and the rest of the switches are turned off. Refer to Figure 9 , which is called State Four.

[0060] Since Q7 is turned on, the voltage - dividing branch is short - circuited, and the current flow direction of the second twin circuit is as Figure 9 shown by the lower red arrow. Due to the one - way conductivity of the diode, capacitor C6 is in the energy - storage state; since Q2 is closed, the current - limiting resistor is short - circuited, and the current flow direction of the first twin circuit is as Figure 5 shown by the upper red arrow. Capacitor C3 is still in the charging state.

[0061] In L7, Q2, Q7, Q4, and Q5 are turned on, and the rest of the switches are turned off. Refer to Figure 10 , which is called State Five.

[0062] Since Q2 and Q4 are turned on simultaneously, capacitor C6 discharges to the TK - terminal, which is superimposed on the positive voltage of the battery pack, making the voltage at the TK - terminal the sum of the positive voltage of the battery pack and the discharge voltage of capacitor C6. The current flow direction between TK+ and HV - is as Figure 10 shown by the upper green arrow; in coordination with Q5 and Q7 being turned on simultaneously, the current flow direction between TK - and HV+ is as Figure 10 shown by the lower green arrow. At this time, capacitor C3 is still in the charging state.

[0063] In L8, Q2 and Q7 are turned on, and the rest of the switches are turned off, that is, it returns to State Four.

[0064] It is easy to know that L4, L5, and L8 are transitional stages to ensure a safe transition between different states. By designing the parameters of each component in the boost circuit, the boost circuit can output the ±21.6V AC voltage required by LWD. For example, when the battery pack provides a voltage of 10.8V, the boost circuit with the parameter design formula of each component has a voltage doubling effect, thus outputting an AC voltage of ±21.6V. The battery pack here can be composed of 3 lithium-ion or lithium iron phosphate batteries connected in series, with a nominal voltage of 3.6V - 3.7V per cell and a total voltage of 10.8V - 11.1V. Compared with 6 lithium batteries connected in series, 3 lithium batteries connected in series can save 50% of the space.

[0065] For example, Figure 5 The resistor selection in the boost circuit shown can refer to Figure 11 as shown. Since 2.7M * 2 is much larger than 10K * 3, most of the battery pack voltage can be divided by the voltage dividing branch, so that the potential difference across the capacitors C3 / C6 can be close to 10.8V. At the same time, 10K * 3 also has a large resistance compared to the short-circuit branch, so that the potential when the capacitors C3 / C6 store energy is superimposed on the positive pole of the power supply, and thus a voltage close to 21.6V is discharged during discharge. In addition, since the resistance of 2.7M * 2 is very large, it is equivalent to an open circuit during the energy storage stage of the capacitors C3 / C6 and when the load is connected, so that electrical energy can be fully released and losses can be reduced.

[0066] The first and second twin circuits form a parallel oscillation circuit in parallel between TK+ and TK-, and also have the following functions:

[0067] 1. By adjusting the parameters of the oscillation circuit, resonance can be formed at a specific frequency, thereby stabilizing the output voltage, reducing voltage fluctuations, and playing a role in smoothing voltage fluctuations;

[0068] 2. The parallel oscillation circuit can effectively filter out high-frequency noise and harmonic components in the power supply through its frequency selection characteristics. The harmonic suppression ability of the oscillation circuit helps to improve the purity of the output voltage and reduce the impact on the load;

[0069] 3. The parallel oscillation circuit also has the function of reactive power compensation. It can introduce a reactive component opposite to the inductive or capacitive load in the load current, thereby improving the power factor of the entire system and reducing the apparent power demand of the power supply;

[0070] 4. In addition, the parallel oscillation circuit also has the function of protecting the circuit. For example, the parallel oscillation circuit can absorb excess voltage under overvoltage conditions to prevent too high voltage from directly acting on the load, thereby protecting the load device from damage; when the load is short-circuited, the parallel oscillation circuit can respond quickly, limit the growth of the short-circuit current, and provide a certain degree of protection.

[0071] In addition, this boost circuit is relatively simple and does not require magnetic components, so it is relatively easy to design and manufacture. Since a bulky transformer is not used, the boost circuit can achieve a smaller size design, thus meeting the miniaturization requirements of LWD. Compared with the transformer boost circuit, the charge pump boost circuit generates less electromagnetic interference.

[0072] To save space to a greater extent, MOS transistors are used for switches Q1 - Q8, and the entire circuit is constructed in the form of an integrated circuit, so that the space occupied by circuit module 200 is hardly increased.

[0073] In the present invention, the battery module and the circuit module are placed in the same short section, realizing the effective integration of the circuit module and the battery module. In Figure 2 、 Figure 3 In the specific example shown, two battery mounting grooves 101 and three circuit mounting grooves 102 are provided on the outer periphery of the circuit skeleton 100. The battery module 200 and the circuit module 300 are circumferentially arranged around the circuit skeleton 100, saving the axial space of the LWD. The fixing method of the mounting grooves can achieve stable fixation while isolating the components, effectively avoiding mutual interference between the two.

[0074] Since the battery has a service life cycle, the battery module 200 is detachably fixed in the battery mounting groove 101 for easy battery replacement. Specifically, a battery cover plate 103 is detachably fixed along the battery mounting groove 101 of the circuit skeleton 100. The battery cover plate 103 and the battery mounting groove 101 form a clamping fixation for the battery module 200, see Figure 2 . The battery cover plate 103 can be detachably fixed to the circuit skeleton 100 by screws. This detachable structure not only facilitates installation and disassembly, but also improves the stability and reliability of the LWD. Since the material of the battery outer cylinder 310 is relatively brittle, the battery cover plate 103 is made of high-strength and high-temperature resistant plastic PEEK material.

[0075] To facilitate the connection of the power line, a wire groove 104 is provided at one end of the battery mounting groove 101. The electrode lead 204 of the battery module 200 passes through the wire groove 104 and is connected to the plug connector 110 fixed on the circuit skeleton 100.

[0076] The circuit module 300 is fixed in the circuit mounting groove 102, see Figure 1 , and includes a cover 201, a support member 202 for supporting the cover 201, and a printed circuit board fixed below the cover 201. The printed circuit board includes the above-mentioned boost circuit. The above structure provides a good circuit path and protection for the battery module 200 and the circuit module 300, ensures the fixation of the relative position of the printed circuit board, and improves the stability and communication effect of the circuit module 300.

[0077] The circuit module 300 is a unit used for testing the circuit. According to different functions, it can be divided into different modules, such as a power control module, a main control module, or a receiving and transmitting module, etc. Since components will generate heat during the operation of the printed circuit board, in order to facilitate heat dissipation, a number of holes 203 are provided on the cover 201, and the holes 203 also play a role in weight reduction to a certain extent.

[0078] Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art and related fields without making creative efforts shall fall within the scope of protection of the present invention.

Claims

1. A power supply sub - section for a logging - while - drilling instrument, comprising a battery module (200) and a circuit module (300) detachably fixed to a circuit framework (100), characterized in that, The circuit module (300) includes a boost circuit for converting DC to AC; The boost circuit includes two sets of twin circuits. Each set of twin circuits includes a first switch branch, a voltage dividing branch, a charge and discharge branch, and a second switch branch connected in parallel. The two ends of these four branches are respectively connected to the positive and negative electrodes of the battery pack; both the first and second switch branches include two switches connected in series and not closed simultaneously. The connection point of the two switches in the first switch branch is also connected to the negative electrode of the battery pack through a current limiting resistor; The output voltage of the boost circuit is taken from the connection points of the two switches in the second switch branches of the two sets of twin circuits. By controlling the opening and closing states of the four switches in the two sets of twin circuits, the two charge and discharge branches present different states of charging, energy storage, and discharging; when the charge and discharge branch is in the discharging state, it is superimposed with the battery pack voltage and output to the connection points of the second switch branches in parallel with it respectively, so as to achieve the boost output of DC to AC.

2. The power supply sub - section of the logging - while - drilling instrument according to claim 1, characterized in that, At least one battery installation groove (101) and at least one circuit installation groove (102) are provided on the outer periphery of the circuit skeleton (100) to isolate the battery module (200) from the circuit module (300).

3. The power supply sub - section of the logging - while - drilling instrument according to claim 2, characterized in that, A battery cover plate (103) is detachably fixed along the battery installation groove (101) of the circuit skeleton (100). The battery cover plate (103) and the battery installation groove (101) form a clamping fixation for the battery module (200).

4. The power supply sub-section of the logging-while-drilling instrument according to claim 2 or 3, characterized in that A wiring groove (104) is provided at one end of the battery installation groove (101). The electrode lead (204) of the battery module (200) passes through the wiring groove (104) and is connected to the plug-in connector (110) fixed on the circuit skeleton (100).

5. The power supply sub-section of the logging-while-drilling instrument according to claim 2, characterized in that, The circuit module (300) is fixed in the circuit installation groove (102) and includes a cover (201), a support member (202) for supporting the cover (201), and a printed circuit board fixed below the cover (201).

6. The power supply sub-section of the logging-while-drilling instrument according to claim 5, characterized in that, A number of holes (203) are provided on the cover (201).

7. The power supply sub-section of the logging-while-drilling instrument according to claim 1, characterized in that, A through hole (105) serving as a slurry channel is provided through the inside of the circuit skeleton (100).

8. The power supply sub - section of the logging - while - drilling instrument according to claim 1, wherein, The two sets of twin circuits are respectively the first and second twin circuits. The charge and discharge branch of the first twin circuit is denoted as the first charge and discharge branch, and the charge and discharge branch of the second twin circuit is denoted as the second charge and discharge branch. The two ends of the output voltage of the boost circuit are respectively denoted as TK+ and TK-, where TK+ is taken from the first twin circuit and TK- is taken from the second twin circuit; The positive electrode of the battery pack is connected to the voltage dividing branch, the charge and discharge branch, and the second switch branch through a diode; the first switch branch of the first twin circuit includes the first and second switches connected in series, and the second switch branch of the first twin circuit includes the third and fourth switches connected in series; the first switch branch of the second twin circuit includes the seventh and eighth switches connected in series, and the second switch branch of the second twin circuit includes the fifth and sixth switches connected in series; The boost circuit operates in the following eight different stages, presenting five different states: L1, the first to eighth switches are all off, and the battery pack charges the first and second charge and discharge branches respectively; L2, the first and eighth switches are turned on, and the rest of the switches are turned off. Since the first switch is closed and considering the unidirectional conductivity of the diode, the first charge-discharge branch is in the energy storage state, and the second charge-discharge branch is still in the charging state; L3, the first, third, sixth, and eighth switches are turned on, and the rest of the switches are turned off. Since the third and sixth switches are turned on, the first charge-discharge branch discharges to the TK+ terminal and is superimposed on the positive voltage of the battery pack. At this time, the second charge-discharge branch is still in the charging state; L4, the first and eighth switches are turned on, and the rest of the switches are turned off, that is, it returns to the state of L2; L5, all the first to eighth switches are turned off, that is, it returns to the state of L1; L6, the second and seventh switches are turned on, and the rest of the switches are turned off. Since the seventh switch is turned on and considering the unidirectional conductivity of the diode, the second charge-discharge branch is in the energy storage state, and the first charge-discharge branch is still in the charging state; L7, the second, fourth, fifth, and seventh switches are turned on, and the rest of the switches are turned off. Since the fourth and seventh switches are turned on, the second charge-discharge branch discharges to the TK- terminal and is superimposed on the positive voltage of the battery pack. At this time, the first charge-discharge branch is still in the charging state; L8, the second and seventh switches are turned on, and the rest of the switches are turned off, that is, it returns to the state of L6.

9. The power supply sub-section of the logging-while-drilling instrument according to claim 1 or 8, characterized in that The switch uses a MOS transistor.

10. The power supply sub-section of the logging-while-drilling tool according to claim 9, characterized in that, It is constructed in the form of an integrated circuit.

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