Cable partial discharge detector capable of reducing interference

Abstract

The invention discloses a cable partial discharge detector capable of reducing interference, and belongs to the technical field of cable partial discharge detection.The cable partial discharge detector comprises a shell, an electrode reversing mechanism and a wire mechanism, a double-layer sound insulation glass plate is arranged in the shell, and a honeycomb sound absorption plate is installed on one side of the double-layer sound insulation glass plate; the interior of the shell is divided into two sections through a double-layer sound insulation glass plate and a honeycomb sound absorption plate, a circuit board is arranged in the section on one side of the double-layer sound insulation glass plate, a filter is installed on the circuit board, a display screen and a control button are arranged on the upper surface of the shell, and the display screen and the control button are both connected with the circuit board through wires. And an electrode reversing mechanism is arranged in an interval on one side of the honeycomb acoustic board. According to the invention, an anti-interference structure is arranged, and the two copper hooks on the anti-interference structure can be randomly hooked on the cable without considering the current direction in the cable, so that convenient and rapid detection can be realized.

Description

Technical Field

[0001] The invention relates to the technical field of cable discharge detection, in particular to a cable partial discharge detector capable of reducing interference. Background Art

[0002] As an important carrier of electric energy transmission in the power system, cables are widely used in various links such as power generation, transmission, transformation and distribution. Their safe and reliable operation is crucial to ensure the stability and continuity of power supply. Once a cable fails, it may cause a large-scale power outage, which will have a serious impact on industrial production, commercial activities and residents' lives. At the same time, the repair of cable failures often takes a long time and is costly. Cable partial discharge has certain hazards. For example, cable partial discharge is an early manifestation of insulation damage and will accelerate insulation aging. In order to reduce or prevent insulation damage or insulation aging, cable partial discharge needs to be detected. The existing cable partial discharge detector still has the following technical problems when in use, such as: 1. The existing cable partial discharge detector is not equipped with an anti-interference structure during use, which makes the existing discharge detector inaccurate due to interference from other external factors when in use; 2. During the use of the existing cable partial discharge detector, different copper hooks need to be hooked at different positions according to the flow direction of the cable current. For example, a cable partial discharge current detection device disclosed with publication number CN217689262U and publication date October 28, 2022, the positive copper hook and the negative copper hook on it need to be hooked at the correct position of the cable for detection, which makes the existing discharge detector inconvenient when in use; Therefore, a cable partial discharge detector that can reduce interference is needed to solve the above problems. Summary of the invention

[0003] The object of the present invention is to provide a cable partial discharge detector capable of reducing interference, so as to solve the problem in the above background technology that the existing cable partial discharge detector is not provided with an anti-interference mechanism and is not convenient during detection.

[0004] To achieve the above object, the present invention provides the following technical solutions: A cable partial discharge detector capable of reducing interference comprises a shell, an electrode reversing mechanism and a conductor mechanism, wherein a double-layer soundproof glass plate is arranged inside the shell, and a honeycomb sound-absorbing plate is installed on one side of the double-layer soundproof glass plate, and the inside of the shell is divided into two sections by the double-layer soundproof glass plate and the honeycomb sound-absorbing plate, a circuit board is arranged in the section on one side of the double-layer soundproof glass plate, and a filter is installed on the circuit board, a display screen and a control button are arranged on the upper surface of the shell, and the display screen and the control button are connected to the circuit board wires, and the honeycomb sound-absorbing plate is provided ... An electrode reversing mechanism is provided in the section on one side of the board, and a slide groove is provided on the inner wall of the shell in the section on one side of the honeycomb sound absorbing board, and one end of a slide rod is slidably connected to the slide groove, and the other end of the slide rod is connected to the electromagnetic sheet, and the electromagnetic sheet and the circuit board are connected in parallel to the wire mechanism, the double-layer sound insulation glass plate and the honeycomb sound absorbing board are provided with sealing plugs passing through both sides thereof, and the shell in the section on one side of the honeycomb sound absorbing board is also provided with a sealing plug passing through both sides thereof, and the wire mechanism is seamlessly sealed and passes through the double-layer sound insulation glass plate, the honeycomb sound absorbing board and the sealing plug on the shell.

[0005] Preferably, the shell is made of copper and insulating plastic, and the copper is embedded in the insulating plastic, and a shielding cover is formed by the copper to reduce electromagnetic radiation.

[0006] Preferably, the electrode reversing mechanism includes a shaft, a cam, a support block, a shaft tube and a twisted rod, the shaft bearing is connected to the interval on one side of the honeycomb sound absorbing plate, and two cams are keyed on the shaft, a support block is fixedly connected to the inner side of the shell in the interval on one side of the honeycomb sound absorbing plate, and the support block is penetrated by the shaft tube bearing, the shaft tube is penetrated by the twisted rod thread, and electromagnetic sheets are connected to both ends of the twisted rod.

[0007] Preferably, the wire winding directions on the two electromagnetic sheets are opposite, and the side of the electromagnetic sheet facing the shaft is a curved surface, and the two electromagnetic sheets correspond to the two cams respectively.

[0008] Preferably, the inner side of the shaft tube and the outer side of the twisted rod are provided with matching twisted threads, and the axes of the shaft tube, the twisted rod and the shaft rod are parallel and coplanar.

[0009] Preferably, the conductor mechanism includes an external circuit, a copper hook, a connecting wire, an electric slip ring, a diode circuit, a mother electrode sheet, a connection wire, a sub-electrode sheet and a connecting wire, the connection wire seamlessly seals the sealing plug on the shell, and the end of the connection wire extending outside the shell is connected to the external circuit, and a copper hook is installed on the external circuit, the mother electrode sheet is fixedly connected to the inner side of the shell in the section on one side of the honeycomb sound absorbing board, and the mother electrode sheet is in contact with and connected to the corresponding sub-electrode sheet, the position where the mother electrode sheet is connected to the sub-electrode sheet is provided with a protrusion, and the position where the mother electrode sheet is connected to the sub-electrode sheet is elastic, and the protrusion and the mother electrode sheet have an elastic setting, When the mother electrode sheet and the sub-electrode sheet are electrically contacted and connected, the two can be connected relatively stably to avoid easy loosening. The two sub-electrode sheets are symmetrically arranged on the outside of the shaft tube, and two electric slip rings are arranged, and the two electric slip rings are respectively connected to the outside of the shaft tube and the outside of the shaft rod by bearings. The electric slip ring on the outside of the shaft tube is connected to the electromagnetic sheet through a connecting line, and the electric slip ring on the outside of the shaft tube is electrically connected to the connecting line. The two electric slip rings are connected through a diode circuit, and the electric slip ring on the outside of the shaft rod is connected to the circuit board through a connecting line, and the connecting line seamlessly seals and penetrates the sealing plug on the double-layer sound insulation glass plate and the honeycomb sound absorption plate.

[0010] Preferably, the external circuit, the copper hook and the mother electrode sheet are each provided with two groups, and the mother electrode sheet is insulated and connected to the shell.

[0011] Preferably, the external circuit, copper hook, mother electrode sheet, sub-electrode sheet, electromagnetic sheet, connecting wire and electric slip ring on the outside of the shaft tube constitute loop a when the two copper hooks are electrically connected, and the external circuit, copper hook, mother electrode sheet, sub-electrode sheet, electric slip ring on the outside of the shaft tube, connecting wire, electric slip ring on the outside of the shaft rod and diode circuit constitute loop b when the two copper hooks are electrically connected, and the electromagnetic sheet and the circuit board are connected in parallel through loop a and loop b, and a switch is provided on loop a, and the switch is electrically connected to the circuit board.

[0012] Preferably, the communication line movably passes through the support block, and the two electromagnetic sheets are arranged in parallel.

[0013] Preferably, the two cams are both made of magnetic material, and the ends opposite to the corresponding electromagnetic sheets repel or attract each other. When the a loop is electrically connected in the forward direction, the upper cam and the upper electromagnetic sheet attract each other, and the lower cam and the lower electromagnetic sheet repel each other. When the a loop is electrically connected in the reverse direction, the upper cam and the upper electromagnetic sheet repel each other, and the lower cam and the lower electromagnetic sheet attract each other.

[0014] Compared with the prior art, the present invention has the following beneficial effects: the cable partial discharge detector capable of reducing interference is not only provided with an anti-interference structure, but also has two copper hooks thereon that can be hooked on the cable at will without considering the current direction in the cable, thereby realizing convenient and quick detection: 1. By setting the filter, the interference signal in a specific frequency range can be removed. The shell adopts a combination of insulating plastic and metal to form a shielding cover, which can reduce or prevent the interference of electromagnetic radiation. In addition, the sound insulation structure composed of double-layer sound insulation glass plate and honeycomb sound absorption plate can reduce the interference of noise on the sensor installed on the circuit board in the detector, thereby improving the detection ability of partial discharge signals. 2. No matter how the copper hook on the detector is hooked on the cable, the a-loop composed of the external circuit, copper hook, mother electrode sheet, sub-electrode sheet, electromagnetic sheet, connecting line and the electric slip ring outside the shaft tube can be electrically connected, so that the electromagnetic sheet can generate magnetism. When the upper electromagnetic sheet and the upper cam attract each other, the twisted rod is squeezed and moved downward, thereby driving the forward shaft tube to rotate 180°. When the upper electromagnetic sheet and the upper cam repel each other, the twisted rod is squeezed and moved upward, thereby driving the reverse shaft tube to rotate 180°. Through the rotation of the shaft tube, the positions of the two sub-electrode sheets are changed, so that no matter how the copper hook is hooked on the cable, the current can flow to the circuit board through the diode circuit to realize partial discharge detection of the cable, thereby realizing convenient and fast detection. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a schematic diagram of the main structure of the present invention; Figure 2 It is a schematic diagram of a partial cross-sectional structure of the present invention; Figure 3 For the present invention Figure 2 A schematic diagram of the enlarged structure of point A; Figure 4 It is a schematic diagram of the local structure of the present invention; Figure 5 For the present invention Figure 4 A schematic diagram of the enlarged structure of point B in the middle; Figure 6 It is a schematic diagram of the connection structure of the connecting wire and the connecting wire of the present invention; Figure 7 It is a schematic diagram of a partial top view of the structure of the present invention; Figure 8 For the present invention Figure 7 Schematic diagram of the enlarged structure at point C in the middle.

[0016] In the figure: 1. Shell; 2. External circuit; 3. Copper hook; 4. Circuit board; 5. Filter; 6. Double-layer soundproof glass plate; 7. Honeycomb sound-absorbing board; 8. Shaft; 9. Cam; 10. Connecting wire; 11. Electric slip ring; 12. Diode circuit; 13. Support block; 14. Shaft tube; 15. Twisted rod; 16. Electromagnetic sheet; 17. Slide rod; 18. Slide groove; 19. Mother electrode sheet; 20. Connection line; 21. Sealing plug; 22. Sub-electrode sheet; 23. Connecting line. DETAILED DESCRIPTION

[0017] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0018] See also Figure 1-Figure 8 , the present invention provides the following technical solutions: Embodiment 1:

[0019] In order to solve the problem that the cable partial discharge detector in the past is not provided with an anti-interference structure, which easily leads to inaccurate measurement structure, the following technical solution is provided, specifically, a cable partial discharge detector that can reduce interference, including a shell 1, an electrode reversing mechanism and a conductor mechanism, a double-layer soundproof glass plate 6 is arranged inside the shell 1, and a honeycomb sound-absorbing plate 7 is installed on one side of the double-layer soundproof glass plate 6, the inside of the shell 1 is divided into two sections by the double-layer soundproof glass plate 6 and the honeycomb sound-absorbing plate 7, a circuit board 4 is arranged in the section on one side of the double-layer soundproof glass plate 6, and a filter 5 is installed on the circuit board 4, a display screen and a control button are arranged on the upper surface of the shell 1, and the display screen and the control button They are all connected to the circuit board 4 by wires. The double-layer soundproof glass plate 6 and the honeycomb sound-absorbing plate 7 are provided with sealing plugs 21 penetrating both sides thereof, and the shell 1 on one side of the honeycomb sound-absorbing plate 7 is also provided with a sealing plug 21 penetrating both inside and outside thereof. The wire mechanism seamlessly seals and penetrates the double-layer soundproof glass plate 6, the honeycomb sound-absorbing plate 7 and the sealing plug 21 on the shell 1. The shell 1 is made of copper and insulating plastic, and copper is embedded in the inside of the insulating plastic. A shielding cover is formed by copper to reduce electromagnetic radiation. The noise reduction structure formed by the double-layer soundproof glass plate 6 and the honeycomb sound-absorbing plate 7 is used to reduce the interference of noise on the sensor installed on the circuit board 4 in the detector, thereby improving the detection capability of partial discharge signals. Embodiment 2:

[0020] In order to solve the problem that the cable partial discharge detector needs to be correctly connected to the cable to measure, resulting in inconvenient and inefficient detection, the following technical solution is provided. Specifically, an electrode reversing mechanism is provided in the section on one side of the honeycomb sound absorbing plate 7, and a slide groove 18 is provided on the inner wall of the shell 1 in the section on one side of the honeycomb sound absorbing plate 7, and one end of a slide rod 17 is slidably connected to the slide groove 18, and the other end of the slide rod 17 is connected to the electromagnetic sheet 16, and the electromagnetic sheet 16 and the circuit board 4 are connected in parallel to the wire mechanism.

[0021] The electrode reversing mechanism includes a shaft rod 8, a cam 9, a support block 13, a shaft tube 14 and a twisted rod 15. The shaft rod 8 is connected to the section on one side of the honeycomb sound absorbing plate 7 by a bearing, and two cams 9 are keyed on the shaft rod 8. The inner side of the shell 1 in the section on one side of the honeycomb sound absorbing plate 7 is fixedly connected with a support block 13, and the support block 13 is penetrated by the shaft tube 14 bearing, and the shaft tube 14 is penetrated by the twisted rod 15 thread, and both ends of the twisted rod 15 are connected with electromagnetic sheets 16, the wire winding directions on the two electromagnetic sheets 16 are opposite, and the side of the electromagnetic sheet 16 facing the shaft rod 8 is a curved surface, and the two electromagnetic sheets 16 correspond to the two cams 9 respectively. When in use, the twisted rod 15 is squeezed by the cam 9 on the electromagnetic sheet 16 and moves along its axis. The tube 14 is connected by a twisted thread, and the shaft tube 14 can only rotate but not move, so the shaft tube 14 will rotate when the twisted rod 15 moves along its axis. When the shaft tube 14 rotates, the positions of the two sub-electrode sheets 22 will be swapped, thereby changing the direction of current flow. The inner side of the shaft tube 14 and the outer side of the twisted rod 15 are provided with matching twisted threads, and the axes of the shaft tube 14, the twisted rod 15 and the shaft rod 8 are parallel and coplanar. The wire mechanism includes an external circuit 2, a copper hook 3, a connecting wire 10, an electric slip ring 11, a diode circuit 12, a mother electrode sheet 19, a connection wire 20, a sub-electrode sheet 22 and a connecting wire 23. The connection wire 20 seamlessly seals the sealing plug 21 on the housing 1, and the end of the connection wire 20 extending outside the housing 1 is connected to the external circuit 2. The mother electrode sheet 19 is fixedly connected to the inner side of the shell 1 in the section on one side of the honeycomb sound absorbing panel 7, and the mother electrode sheet 19 is in contact with the corresponding sub-electrode sheet 22. The position where the mother electrode sheet 19 and the sub-electrode sheet 22 are connected is provided with a protrusion, and the position where the mother electrode sheet 19 and the sub-electrode sheet 22 are connected is elastic. The protrusion and the mother electrode sheet 19 have elastic settings, so that when the mother electrode sheet 19 and the sub-electrode sheet 22 are electrically contacted and connected, the two can be connected more stably to avoid easy loosening. The two sub-electrode sheets 22 are symmetrically arranged on the outside of the shaft tube 14. Two electric slip rings 11 are provided, and the two electric slip rings 11 are respectively connected to the outside of the shaft tube 14 and the outside of the shaft rod 8 by bearings. The shaft tube 14 The outer electric slip ring 11 is connected to the electromagnetic sheet 16 through the interconnection line 23, and the electric slip ring 11 on the outer side of the shaft tube 14 is electrically connected to the interconnection line 23, the two electric slip rings 11 are connected through the diode line 12, and the electric slip ring 11 on the outer side of the shaft rod 8 is connected to the circuit board 4 through the connecting line 10, and the connecting line 10 seamlessly seals and penetrates the sealing plug 21 on the double-layer soundproof glass plate 6 and the honeycomb sound-absorbing plate 7, the external circuit 2, the copper hook 3 and the mother electrode sheet 19 are each provided with two groups, and the mother electrode sheet 19 is insulated and connected to the shell 1, and the external circuit 2, the copper hook 3, the mother electrode sheet 19, the sub-electrode sheet 22, the electromagnetic sheet 16, the interconnection line 23 and the electric slip ring 11 on the outer side of the shaft tube 14 form a circuit when the two copper hooks 3 are electrically connected.And the external circuit 2, copper hook 3, mother electrode sheet 19, sub-electrode sheet 22, electric slip ring 11 outside shaft tube 14, connecting wire 10, electric slip ring 11 outside shaft rod 8 and diode circuit 12 form b circuit when two copper hooks 3 are electrically connected, and electromagnetic sheet 16 and circuit board 4 are connected in parallel through a circuit and b circuit, a switch is arranged on circuit a, and switch is electrically connected to circuit board 4, when the position of two copper hooks 3 connected to cables is incorrect, that is, when two copper hooks 3 are connected to cables, the current direction cannot flow through diode circuit 12, at this time, current will flow through circuit a, so that electromagnetic sheet 16 generates suction or repulsion, so that cam 9 at one end contacts with its corresponding electromagnetic sheet 16, and cam 9 at the other end moves away from its corresponding electromagnetic sheet 16, at this time, twisted rod 15 is squeezed and moved, so that shaft tube 14 rotates 180°, so that the position of two sub-electrode sheets 22 The positions are swapped. When the positions of the two sub-electrode sheets 22 are swapped, the current will flow through the diode circuit 12, so that the circuit board 4 controls the switch of the a circuit to disconnect the switch. At this time, since the mother electrode sheet 19 is elastic, the two sub-electrode sheets 22 cannot swap positions in an instant, which can ensure that only the b circuit is in a connected state after that, thereby facilitating the partial discharge detection of the cable. The connecting line 23 is movable through the support block 13, and the two electromagnetic sheets 16 are arranged in parallel. The two cams 9 are both made of magnetic materials, and the ends opposite to the corresponding electromagnetic sheets 16 repel or attract each other. When the a circuit is electrically connected in the forward direction, the upper cam 9 and the upper electromagnetic sheet 16 attract each other, and the lower cam 9 and the lower electromagnetic sheet 16 repel each other. When the a circuit is electrically connected in the reverse direction, the upper cam 9 and the upper electromagnetic sheet 16 repel each other, and the lower cam 9 and the lower electromagnetic sheet 16 attract each other. ,

[0022] The contents not described in detail in this specification belong to the prior art known to professional and technical personnel in this field.

[0023] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A cable partial discharge detector capable of reducing interference, comprising a housing (1), an electrode reversing mechanism and a conductor mechanism, characterized in that: The shell (1) is provided with a double-layer soundproof glass plate (6) inside, and a honeycomb sound absorbing plate (7) is installed on one side of the double-layer soundproof glass plate (6); the inside of the shell (1) is divided into two sections by the double-layer soundproof glass plate (6) and the honeycomb sound absorbing plate (7); a circuit board (4) is provided in the section on one side of the double-layer soundproof glass plate (6), and a filter (5) is installed on the circuit board (4); a display screen and control buttons are provided on the upper surface of the shell (1), and the display screen and the control buttons are connected to the circuit board (4) by wires; an electrode reversing mechanism is provided in the section on one side of the honeycomb sound absorbing plate (7), and the section on one side of the honeycomb sound absorbing plate (7) is provided with an electrode reversing mechanism. The inner wall of the shell (1) is provided with a slide groove (18), and one end of a slide rod (17) is slidably connected to the slide groove (18), the other end of the slide rod (17) is connected to the electromagnetic sheet (16), and the electromagnetic sheet (16) and the circuit board (4) are connected in parallel to the wire mechanism, the double-layer sound insulation glass plate (6) and the honeycomb sound absorption plate (7) are provided with sealing plugs (21) penetrating both sides thereof, and the shell (1) in the section on one side of the honeycomb sound absorption plate (7) is also provided with a sealing plug (21) penetrating both sides thereof, and the wire mechanism is seamlessly sealed and penetrates the double-layer sound insulation glass plate (6), the honeycomb sound absorption plate (7) and the sealing plug (21) on the shell (1).

2. A cable partial discharge detector capable of reducing interference according to claim 1, characterized in that: The shell (1) is made of copper and insulating plastic, and the copper is embedded in the insulating plastic. The copper forms a shielding cover to reduce electromagnetic radiation.

3. A cable partial discharge detector capable of reducing interference according to claim 2, characterized in that: The electrode reversing mechanism comprises a shaft (8), a cam (9), a support block (13), a shaft tube (14) and a twisted rod (15); the shaft (8) is bearing-connected in a section on one side of the honeycomb sound absorbing plate (7); two cams (9) are key-connected on the shaft (8); the support block (13) is fixedly connected to the inner side of the housing (1) in the section on one side of the honeycomb sound absorbing plate (7); the support block (13) is pierced by a shaft tube (14) bearing; the shaft tube (14) is threadedly pierced by the twisted rod (15); and both ends of the twisted rod (15) are connected to electromagnetic sheets (16).

4. A cable partial discharge detector capable of reducing interference according to claim 3, characterized in that: The wire winding directions on the two electromagnetic sheets (16) are opposite, and the side surface of the electromagnetic sheet (16) facing the shaft (8) is a curved surface, and the two electromagnetic sheets (16) correspond to the two cams (9) respectively.

5. A cable partial discharge detector capable of reducing interference according to claim 4, characterized in that: The inner side of the shaft tube (14) and the outer side of the twisted rod (15) are provided with matching twisted threads, and the axes of the shaft tube (14), the twisted rod (15) and the shaft rod (8) are parallel and coplanar.

6. A cable partial discharge detector capable of reducing interference according to claim 5, characterized in that: The conductor mechanism comprises an external circuit (2), a copper hook (3), a connecting wire (10), an electric slip ring (11), a diode circuit (12), a mother electrode sheet (19), a connection wire (20), a sub-electrode sheet (22) and a connecting wire (23); the connection wire (20) is seamlessly sealed with a sealing plug (21) on the housing (1); and the end of the connection wire (20) extending outside the housing (1) is connected to the external circuit (2); and the copper hook (3) is installed on the external circuit (2); the mother electrode sheet (19) is fixedly connected to the inner side of the housing (1) in a section on one side of the honeycomb sound absorbing plate (7); and the mother electrode sheet (19) is in contact with and connected to the corresponding sub-electrode sheet (22); a protrusion is provided at a position where the mother electrode sheet (19) and the sub-electrode sheet (22) are connected; and the position where the mother electrode sheet (19) and the sub-electrode sheet (22) are connected is elastic, and the protrusion and the mother electrode sheet (19) are provided with elasticity. When the mother electrode sheet (19) and the sub-electrode sheet (22) are electrically contacted and connected, the two can be stably connected to avoid easy loosening. The two sub-electrode sheets (22) are symmetrically arranged on the outside of the shaft tube (14). Two electric slip rings (11) are arranged, and the two electric slip rings (11) are respectively connected to the outside of the shaft tube (14) and the outside of the shaft rod (8) by bearings. The electric slip rings (11) on the outside of the shaft tube (14) are connected via a connecting line (23). The electric slip ring (11) is connected to the electromagnetic sheet (16), and the electric slip ring (11) on the outside of the shaft tube (14) is electrically connected to the connecting line (23), the two electric slip rings (11) are connected to each other via a diode circuit (12), and the electric slip ring (11) on the outside of the shaft rod (8) is connected to the circuit board (4) via a connecting line (10), and the connecting line (10) is seamlessly sealed and penetrates the sealing plug (21) on the double-layer sound insulation glass plate (6) and the honeycomb sound absorption plate (7).

7. A cable partial discharge detector capable of reducing interference according to claim 6, characterized in that: The external circuit (2), the copper hook (3) and the mother electrode sheet (19) are each provided in two groups, and the mother electrode sheet (19) is insulated and connected to the housing (1).

8. The cable partial discharge detector capable of reducing interference according to claim 7, characterized in that: The external circuit (2), the copper hook (3), the mother electrode sheet (19), the sub-electrode sheet (22), the electromagnetic sheet (16), the connecting line (23) and the electric slip ring (11) outside the shaft tube (14) form an a circuit when the two copper hooks (3) are electrically connected, and the external circuit (2), the copper hook (3), the mother electrode sheet (19), the sub-electrode sheet (22), the electric slip ring (11) outside the shaft tube (14), the connecting line (10), the electric slip ring (11) outside the shaft rod (8) and the diode circuit (12) form a b circuit when the two copper hooks (3) are electrically connected. The electromagnetic sheet (16) and the circuit board (4) are connected in parallel via the a circuit and the b circuit. A switch is provided on the a circuit, and the switch is electrically connected to the circuit board (4).

9. The cable partial discharge detector capable of reducing interference according to claim 8, characterized in that: The connecting line (23) is movably arranged to penetrate the supporting block (13), and the two electromagnetic sheets (16) are arranged in parallel.

10. A cable partial discharge detector capable of reducing interference according to claim 9, characterized in that: The two cams (9) are both made of magnetic material, and the ends opposite to the corresponding electromagnetic sheets (16) repel or attract each other. When the a circuit is electrically connected in the positive direction, the upper cam (9) and the upper electromagnetic sheet (16) attract each other, and the lower cam (9) and the lower electromagnetic sheet (16) repel each other. When the a circuit is electrically connected in the reverse direction, the upper cam (9) and the upper electromagnetic sheet (16) repel each other, and the lower cam (9) and the lower electromagnetic sheet (16) attract each other.

Images