All-fiber current transformer system with optical cable protection function
By setting protective measures in key areas of the all-fiber current transformer system, the problem of polarization-maintaining optical cables being susceptible to vibration interference is solved, and measurement accuracy and reliability are improved.
Patent Information
- Application Number
- CN202421550022.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-07-02
- Publication Date
- 2025-04-25
- Estimated Expiration
- 2034-07-02
AI Technical Summary
The polarization-maintaining optical cables of all fiber current transformers are susceptible to vibration interference, resulting in low measurement accuracy, high failure rate and poor operating reliability.
A fully fiber current transformer system with optical cable protection function was designed. By setting protective measures such as protective pipes, protective groove boxes and protective hoops in the primary body area, cable trench area, shaft area and control room area, protecting polarized optical cables from vibration.
It effectively reduces the impact of polarization-maintaining optical cables by vibration interference, improves the measurement accuracy and reliability of all-fiber current transformers, and reduces the risk of misoperation and failure rate.
Smart Images
Figure CN222800822U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of power grid safety and electric power metering, and in particular to an all-optical fiber current transformer system with an optical cable protection function. Background Art
[0002] All-fiber current transformers have the advantages of advanced principle, simple insulation structure, large measurement dynamic range, fast dynamic response, etc., and have been widely used in UHV converter stations in recent years. All-fiber current transformers are mainly used for current measurement in DC fields and AC filter fields in converter stations for use in control, protection and monitoring systems. Their measurement accuracy and reliability are of great significance to the reliable operation of DC systems.
[0003] However, compared with traditional electromagnetic current transformers, all-fiber current transformers have a shorter network operation time and lack experience in protecting optical cables and operating and maintaining them. Because the polarized light transmitted in the polarization-maintaining optical cable between the primary body and the acquisition unit has a certain degree of non-reciprocity, when the polarization-maintaining optical cable is vibrated, the phase difference between the "going" and "coming" polarized light cannot be completely eliminated, so the measured value will be disturbed by the vibration. The longer the transmission polarization-maintaining optical cable, the closer the polarization-maintaining optical cable is to the acquisition unit, the greater the vibration interference it will receive, resulting in a higher failure rate and risk of malfunction, and lower operational reliability. In practice, the polarization-maintaining optical cable is easily vibrated by external factors such as wind, contact or collision with external objects, resulting in low measurement accuracy and poor reliability of the all-fiber current transformer. Utility Model Content
[0004] In view of this, in order to address the above shortcomings, it is necessary to propose an all-fiber current transformer system with optical cable protection function to reduce the impact of vibration on the polarization-maintaining optical cable, thereby improving the measurement accuracy of the all-fiber current transformer.
[0005] The utility model provides an all-optical fiber current transformer system with an optical cable protection function, the system comprising: a primary body area, a cable trench area, a shaft area and a control room area; the primary body area is provided with a DC field all-optical fiber current transformer or an AC field all-optical fiber current transformer, the cable trench area is provided with an optical cable trough box, and the control room area is provided with a control box; the polarization-maintaining optical cable led out of the all-optical fiber current transformer passes through the optical cable trough box in the cable trench area and the shaft area in sequence, and is connected to the control box in the control room area; the polarization-maintaining optical cable located in the primary body area is protected by a protective tube and a protective trough box.
[0006] Preferably, the DC field all-fiber current transformer includes a DC primary body, a first support frame and a first fiber optic fusion box, the first support frame is installed on the ground, the first fiber optic fusion box is installed on the side of the first support frame, and the DC primary body is installed on the upper end of the first support frame; a first fishhook-shaped protective steel pipe is provided on one side close to the first support frame, one end of the first protective steel pipe extends out of the top of the first support frame by a first preset distance, and the other end is inserted into the ground and then comes out of the ground, and the distance from the lower end of the first fiber optic fusion box is a second preset distance; the self-contained tail cable of the DC primary body is sleeved with a first stainless steel corrugated tube, and the self-contained tail cable sleeved with the first stainless steel corrugated tube is connected to the first fiber optic fusion box after passing through the first protective steel pipe as a whole.
[0007] Preferably, four L-shaped second protective steel pipes are provided at the lower end of the first optical fiber fusion box, one end of each second protective steel pipe is laid below the first optical fiber fusion box, and the other end is laid underground to the cable trench area; a first protective trough box is provided below the first optical fiber fusion box, and the four L-shaped second protective steel pipes all pass through the first protective trough box; the four polarization-maintaining optical cables output from the optical fiber fusion box are all sheathed with a second stainless steel corrugated tube, and each polarization-maintaining optical cable sheathed with the second stainless steel corrugated tube passes through the corresponding second protective steel pipe and is connected to the cable trough box in the cable trench area.
[0008] Preferably, the AC field all-fiber current transformer includes an A-phase primary body, a B-phase primary body, a C-phase primary body, a second support frame and a second fiber optic fusion box. The A-phase primary body, the B-phase primary body, the C-phase primary body and the second support frame are all installed on the ground, and the second fiber optic fusion box is installed on the second support frame; a third protective steel pipe is provided under each phase primary body, one end of the third protective steel pipe is laid to the corresponding primary body, and the other end enters the ground and is laid under the second fiber optic fusion box; the self-contained pigtail of each phase primary body is sleeved with a third stainless steel corrugated tube, and each self-contained pigtail cable sleeved with the third stainless steel corrugated tube is connected to the second fiber optic fusion box after passing through the corresponding third protective steel pipe as a whole.
[0009] Preferably, three fourth protective steel pipes and four L-shaped fifth protective steel pipes are provided at the lower end of the second optical fiber fusion box, one end of each fourth protective steel pipe is laid under the second optical fiber fusion box, and the other end is laid to the corresponding third protective steel pipe after being buried underground, and one end of each fifth protective steel pipe is laid under the second optical fiber fusion box, and the other end is laid to the cable trench area after being buried underground; a second protective trough box is provided under the second optical fiber fusion box, and the four L-shaped fifth protective steel pipes all pass through the second protective trough box; the self-contained tail cables led out from the primary body of each phase pass through the corresponding third protective steel pipe and fourth protective steel pipe in sequence and are connected to the second optical fiber fusion box; the four polarization-maintaining optical cables output from the second optical fiber fusion box are all sheathed with fourth stainless steel corrugated tubes, and each polarization-maintaining optical cable sheathed with the fourth stainless steel corrugated tube is connected to the optical cable trough box in the cable trench area after passing through the corresponding fifth protective steel pipe.
[0010] Preferably, the optical cable trough box is arranged below the cable trench area pipeline and placed close to the inner side of the wall; an L-shaped fireproof partition is arranged on the outer side of the optical cable trough box to enclose the optical cable trough box in the space formed by the fireproof partition and the pipeline wall.
[0011] Preferably, the polarization-maintaining optical cable from the pipeline entering the cable trench area to the optical cable trough box is arranged close to the pipeline wall, and a fifth stainless steel corrugated tube is sleeved on the polarization-maintaining optical cable.
[0012] Preferably, a plurality of protective clamps are provided in the vertical shaft area, the polarization-maintaining optical cable is tightened and fixed in the vertical shaft area by the protective clamps, and a rubber pad is provided on the inner side of each protective clamp.
[0013] Preferably, the protective clamps are arranged at intervals of 50±5 cm.
[0014] Preferably, the control room area is provided with a third protection trough box, the polarization-maintaining optical cables located in the control room area all pass through the third protection trough box, and the inner surface of the third protection trough box is provided with a shock-absorbing pad.
[0015] It can be seen from the above technical scheme that the all-fiber current transformer system with optical cable protection function provided by the embodiment of the utility model includes a primary body area, a cable trench area, a shaft area and a control room area, wherein the primary body area can be provided with a corresponding all-fiber current transformer according to the different current fields or AC fields, an optical cable trough box is provided in the cable trench area, and a control box is provided in the control room, and the polarization-maintaining optical cable led out of the all-fiber current transformer passes through the optical cable trough box in the cable trench area and the shaft area once and is connected to the control box in the control room area, wherein the polarization-maintaining optical cable located in the primary body area is protected by a protective tube and a protective trough box, which can effectively prevent the vibration of the polarization-maintaining optical cable due to factors such as wind force, contact or collision with external objects, thereby reducing the influence of vibration interference on the polarization-maintaining optical cable and improving the measurement accuracy of the all-fiber current transformer. BRIEF DESCRIPTION OF THE DRAWINGS
[0016] Figure 1 A schematic diagram of an all-optical fiber current transformer system with an optical cable protection function for a current field provided by an embodiment of the utility model.
[0017] Figure 2 A schematic diagram of an all-optical fiber current transformer system with optical cable protection function in an AC field provided by an embodiment of the utility model.
[0018] Figure 3 A schematic diagram of a primary body region of a current field provided in an embodiment of the utility model.
[0019] Figure 4 A schematic diagram of a primary body area of an AC field provided in an embodiment of the utility model.
[0020] Figure 5 A schematic diagram of a cable trench area provided in an embodiment of the utility model.
[0021] Figure 6 A schematic diagram of a shaft area provided in an embodiment of the utility model.
[0022] Figure 7 A cross-sectional schematic diagram of a protective clamp provided in an embodiment of the utility model.
[0023] Figure 8 A schematic diagram of protection for a polarization-maintaining optical cable in a control room area provided by an embodiment of the utility model.
[0024] In the figure: primary body area 10, DC primary body 111, first support frame 112, first optical fiber fusion box 113, first protective steel pipe 114, first stainless steel bellows 115, second protective steel pipe 116, first protective trough box 117, A phase primary body 121, B phase primary body 122, C phase primary body 123, second support frame 124, second optical fiber fusion box 125, third protective steel pipe 126, third stainless steel bellows 127, fourth protective steel pipe 128, fifth protective steel pipe 129, second protective trough box 1210, cable trench area 20, optical cable trough box 21, fireproof partition 22, shaft area 30, protective clamp 31, rubber pad 32, control room area 40, third protective trough box 41, shock-absorbing pad 42. DETAILED DESCRIPTION
[0025] In order to more clearly illustrate the technical solutions of the embodiments of the utility model, the drawings required for use in the embodiments are briefly introduced below. Obviously, the drawings described below are some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.
[0026] See also Figure 1-8 The utility model provides an all-optical fiber current transformer system with optical cable protection function, the system comprises: a primary body area 10, a cable trench area 20, a shaft area 30 and a control room area 40; the primary body area 10 is provided with a DC field all-optical fiber current transformer or an AC field all-optical fiber current transformer, the cable trench area 20 is provided with an optical cable trough box 21, and the control room area 40 is provided with a control box; the polarization-maintaining optical cable led out of the all-optical fiber current transformer passes through the optical cable trough box 21 of the cable trench area 20 and the shaft area 30 in turn, and is connected to the control box of the control room area 40; the polarization-maintaining optical cable located in the primary body area 10 is protected by a protective tube and a protective trough box.
[0027] In this embodiment, based on the structure of the all-optical fiber current transformer, the transmission path of the polarization-maintaining optical cable, and taking into account the construction cost, feasibility, and protection effect, an all-optical fiber current transformer system with optical cable protection function is proposed. The system can effectively prevent the polarization-maintaining optical cable from vibrating due to external factors, reduce the influence of vibration on the polarization-maintaining optical cable, and thus avoid abnormal measurement data caused by the vibration of the polarization-maintaining optical cable, resulting in false tripping and DC locking events.
[0028] For the primary body area 10, consider adding galvanized steel pipes from the body insulator to the optical fiber fusion box and from the optical fiber fusion box to the cable trench, and install protective trough boxes on the periphery of the galvanized steel pipes. The polarization-maintaining optical cable needs to pass through the impermeable steel corrugated pipe and then pass through the galvanized steel pipe as a whole for protection. Specifically, the all-optical current transformer in the primary body area 10 is different in the DC field and the AC field. The all-optical current transformer adopts a pillar structure in the DC field and a suspension structure in the AC filter field, so the DC field and AC field are described separately.
[0029] For the DC field, the DC field all-fiber current transformer may include a DC primary body 111, a first support frame 112 and a first optical fiber fusion box 113, the first support frame 112 is installed on the ground, the first optical fiber fusion box 113 is installed on the side of the first support frame 112, and the DC primary body 111 is installed on the upper end of the first support frame 112; a fishhook-shaped first protective steel pipe 114 is arranged on one side close to the first support frame 112, one end of the first protective steel pipe 114 extends out of the top of the first support frame 112 by a first preset distance, and the other end enters the ground and then comes out of the ground, and the distance from the lower end of the first optical fiber fusion box 113 is a second preset distance; the self-contained tail cable of the DC primary body 111 is sheathed with a first stainless steel corrugated tube 115, and the self-contained tail cable sheathed with the first stainless steel corrugated tube 115 is connected to the first optical fiber fusion box 113 after passing through the first protective steel pipe 114 as a whole.
[0030] Furthermore, four L-shaped second protective steel pipes 116 are provided at the lower end of the first optical fiber fusion box 113, one end of each second protective steel pipe 116 is laid to the bottom of the first optical fiber fusion box 113, and the other end is laid to the cable trench area 20 after being buried underground; a first protective trough box 117 is provided at the bottom of the first optical fiber fusion box 113, and the four L-shaped second protective steel pipes 116 all pass through the first protective trough box 117; the four polarization-maintaining optical cables output from the optical fiber fusion box are all sheathed with a second stainless steel corrugated tube, and each polarization-maintaining optical cable sheathed with the second stainless steel corrugated tube passes through the corresponding second protective steel pipe 116 and is connected to the cable trough box 21 in the cable trench area 20.
[0031] In this embodiment, the DC field all-fiber current transformer adopts a pillar structure, the primary body is installed on the first support frame 112, and the first support frame 112 is a steel column. The first optical fiber fusion box 113 is installed on the first support frame 112 and is located at a height of about 1 meter from the ground. For the polarization-maintaining optical cable in the primary body area 10, there are mainly two places that need to be protected: the primary body's own tail cable and the polarization-maintaining optical cable before entering the cable trench area 20. For the self-contained tail cable of the DC primary body 111, consider installing a first protective steel pipe 114 with a diameter of 50mm at one end on one side of the first support frame 112, and the first protective steel pipe 114 is a galvanized steel pipe. The first protective steel pipe 114 is about 150mm away from the top of the first support frame 112, and the other end is underground and then out of the ground to 150mm below the optical fiber fusion box. The self-contained tail cable passes through the first stainless steel corrugated tube 115, and then passes through the galvanized first protective steel pipe 114 as a whole, and finally enters the first optical fiber fusion box 113.
[0032] For the polarization-maintaining optical cable before entering the cable trench area 20, it is considered to lay four galvanized second protective steel pipes 116 with a diameter of 50 mm for protection. One end of the second protective steel pipe 116 is laid to about 150 mm below the first optical fiber fusion box 113, and the other end is laid to the cable trench area 20. Then, at the lower part of the first optical fiber fusion box 113, a 400mm×120mm first protective trough box 117 is installed on the outside of each second protective steel pipe 116, and a certain gap is left between the first protective trough box 117 and the interior. In addition, the polarization-maintaining optical cable from the first optical fiber fusion box 113 to the cable trench needs to pass through the second stainless steel corrugated tube, and then pass through the galvanized second protective steel pipe 116 as a whole, and finally enter the optical cable trough box 21 in the cable trench area 20.
[0033] For the AC field, the AC field all-fiber current transformer includes an A-phase primary body 121, a B-phase primary body 122, a C-phase primary body 123, a second support frame 124 and a second optical fiber fusion box 125. The A-phase primary body 121, the B-phase primary body 122, the C-phase primary body 123 and the second support frame 124 are all installed on the ground, and the second optical fiber fusion box 125 is installed on the second support frame 124; a third protective steel pipe 126 is arranged under each phase primary body, one end of the third protective steel pipe 126 is laid to the corresponding primary body, and the other end enters the ground and is laid under the second optical fiber fusion box 125; the self-contained tail cable of each phase primary body is sleeved with a third stainless steel corrugated tube 127, and each self-contained tail cable sleeved with the third stainless steel corrugated tube 127 is connected to the second optical fiber fusion box 125 after passing through the corresponding third protective steel pipe 126 as a whole.
[0034] Furthermore, three fourth protective steel pipes 128 and four L-shaped fifth protective steel pipes 129 are provided at the lower end of the second optical fiber fusion box 125, one end of each fourth protective steel pipe 128 is laid below the second optical fiber fusion box 125, and the other end is laid underground to the corresponding third protective steel pipe 126, and one end of each fifth protective steel pipe 129 is laid below the second optical fiber fusion box 125, and the other end is laid underground to the cable trench area 20; a second protective groove is provided below the second optical fiber fusion box 125 Box 1210, four L-shaped fifth protective steel tubes 129 all pass through the second protective trough box 1210; the self-contained tail cables led out from each phase primary body pass through the corresponding third protective steel tube 126 and fourth protective steel tube 128 in turn and are connected to the second optical fiber fusion box 125; the four polarization-maintaining optical cables output from the second optical fiber fusion box 125 are all sheathed with a fourth stainless steel corrugated tube, and each polarization-maintaining optical cable sheathed with the fourth stainless steel corrugated tube passes through the corresponding fifth protective steel tube 129 and is connected to the optical cable trough box 21 in the cable trench area 20.
[0035] In this embodiment, the AC field all-fiber current transformer adopts a suspended structure, and the A-phase primary body 121, the B-phase primary body 122, and the C-phase primary body 123 are all installed on the ground cement foundation. The second optical fiber fusion box 125 is installed on the second steel support frame 124 outside the filter fence and is located about 1m above the ground. The A-phase primary body 121, the B-phase primary body 122, and the C-phase primary body 123 of the AC field all-fiber current transformer share a second optical fiber fusion box 125. The AC field also mainly has two places that need to be protected: the primary body's own tail cable and the polarization-maintaining optical cable before entering the cable trench area 20. For the self-contained tail cable of each phase primary body, a galvanized third protective steel pipe 126 with a diameter of 50mm is passed, one end of which is laid to the corresponding primary body, and the other end is laid to the cable branch trench below the second optical fiber fusion box 125 after entering the ground. After passing through the third stainless steel corrugated tube 127 , the self-contained tail cable enters the cable branching groove through the third protective steel tube 126 , and enters the second optical fiber fusion box 125 after passing through the fourth protective steel tube 128 .
[0036] For the protection of the polarization-maintaining optical cable before entering the cable trench, it is considered to set three fourth protection steel pipes 128 at the lower end of the second fusion box, and lay four galvanized fifth protection steel pipes 129 with a diameter of 50 mm. One end of each fourth protection steel pipe 128 is laid to the bottom of the second fusion box, and the other end is laid in the cable branch trench to correspond to the corresponding third protection steel pipe 126. One end of each fifth protection steel pipe 129 is laid to about 150 mm below the second optical fiber fusion box 125, and the other end is laid in the cable trench. The polarization-maintaining optical cable needs to pass through the fourth stainless steel corrugated tube, and then pass through the galvanized fifth protection steel pipe 129 as a whole, and finally enter the optical cable trough box 21 in the cable trench. Finally, at the lower part of the second optical fiber fusion box 125, a 400mm×200mm second protection trough box 1210 is installed on the outside of the fifth protection steel pipe 129, and a certain gap is left between the trough boxes.
[0037] In this way, for the primary body area 10, the polarization-maintaining optical cable located in the primary body area 10 is protected by protective steel pipes, stainless steel bellows, protective trough boxes, etc., which can effectively prevent the vibration of the polarization-maintaining optical cable caused by external factors, thereby reducing the measurement error caused by the vibration of the polarization-maintaining optical cable.
[0038] For the cable trench area 20, consider setting the optical cable trough box 21 below the pipeline in the cable trench area 20 and placing it close to the inner side of the wall, and then use a direct floor-standing or L-shaped fireproof partition 22 to hide and seal the optical cable trough box 21 to prevent objects such as fireproof panels and cover plates from falling and hitting the optical cable trough box 21, causing vibration of the polarization-maintaining optical cable.
[0039] In this embodiment, the optical cable trough box 21 in the cable trench is arranged at the bottom of the pipeline and needs to be placed against the inner side of the wall. The optical cable trough box 21 shall not protrude from the bridge frame in the pipeline. Then, the optical cable trough box 21 is hidden and closed by directly landing or L-shaped fireproof partition 22 to prevent objects such as fireproof panels and cover plates from falling and hitting the optical cable trough box 21, causing vibration of the polarization-maintaining optical cable. In addition, the polarization-maintaining optical cable from the pipeline entering the cable trench area 20 to the optical cable trough box 21 is considered to be set close to the pipeline wall, and the fifth stainless steel corrugated pipe is installed in this section of the polarization-maintaining optical cable.
[0040] For the protection of the shaft area 30, it is considered to set a plurality of protective clamps 31 in the shaft area 30, and the polarization-maintaining optical cable is tightened and fixed by the protective clamps 31 in the shaft area 30, and a rubber pad 32 is provided on the inner side of each protective clamp 31. In this embodiment, for example, for the polarization-maintaining optical cable in the shaft of the control room area 40, according to the actual situation and space on site, a protective clamp 31 can be set every 0.5m to tighten and protect the polarization-maintaining optical cable, and a rubber pad 32 is provided on the inner side of each protective clamp 31 to prevent squeezing of the polarization-maintaining optical cable.
[0041] For the control room area 40, a third protective trough box 41 is considered to be provided, and the polarization-maintaining optical cables located in the control room area 40 all pass through the third protective trough box 41, and the inner surface of the third protective trough box 41 is provided with a shock-absorbing pad 42. In this embodiment, because the control room area 40 is a place where operation and maintenance personnel frequently move, a double protection design scheme of a protective trough box + a shock-absorbing pad 42 is adopted. The third protective trough box 41 can prevent the risk of the bottom plate in the control room area 40 falling and hitting the polarization-maintaining optical cable, and the shock-absorbing pad 42 laid inside the third protective trough box 41 can effectively reduce the vibration effect of the polarization-maintaining optical cable when the third protective trough box 41 is impacted.
[0042] In summary, as an important measuring device in the converter station, the all-fiber current transformer is the basis for ensuring the safe and stable operation of the DC system. In view of the advanced measurement principle and structure of the all-fiber current transformer and the property that the polarization-maintaining optical cable is susceptible to vibration, this scheme takes into account the construction cost, feasibility and the effect of anti-vibration measures, and adds protective measures to the polarization-maintaining optical cable between the all-fiber current transformer body and the control box in the primary body area, cable trench area, shaft area and control room area. The scheme makes full use of the original materials, improves the measurement reliability of the all-fiber current transformer, and effectively avoids the probability and risk of abnormal measurement data caused by the vibration of the polarization-maintaining optical cable, providing a technical reference for the engineering design, on-site construction and reliability of the all-fiber current transformer in the converter station.
[0043] The modules or units in the device of the embodiment of the utility model can be combined, divided and deleted according to actual needs. The above disclosure is only the preferred embodiment of the utility model, and of course it cannot be used to limit the scope of the rights of the utility model. Ordinary technicians in this field can understand that all or part of the processes of the above embodiments are implemented, and equivalent changes made according to the claims of the utility model still fall within the scope of the utility model.
Claims
1. An all-fiber current transformer system with optical cable protection function, characterized in that: The system comprises: a primary body area, a cable trench area, a shaft area and a control room area; the primary body area is provided with a DC field all-optical fiber current transformer or an AC field all-optical fiber current transformer, the cable trench area is provided with an optical cable trough box, and the control room area is provided with a control box; the polarization-maintaining optical cable led out of the all-optical fiber current transformer passes through the optical cable trough box in the cable trench area and the shaft area in sequence, and is connected to the control box in the control room area; the polarization-maintaining optical cable located in the primary body area is protected by a protective tube and a protective trough box.
2. The all-optical fiber current transformer system with optical cable protection function according to claim 1, characterized in that: The DC field all-fiber current transformer includes a DC primary body, a first support frame and a first fiber optic fusion box, the first support frame is installed on the ground, the first fiber optic fusion box is installed on the side of the first support frame, and the DC primary body is installed on the upper end of the first support frame; a first fishhook-shaped protective steel pipe is provided on one side close to the first support frame, one end of the first protective steel pipe extends out of the top of the first support frame by a first preset distance, and the other end is inserted into the ground and then comes out of the ground, and the distance from the lower end of the first fiber optic fusion box is a second preset distance; the self-contained tail cable of the DC primary body is sheathed with a first stainless steel corrugated tube, and the self-contained tail cable sheathed with the first stainless steel corrugated tube is connected to the first fiber optic fusion box after passing through the first protective steel pipe as a whole.
3. The all-optical fiber current transformer system with optical cable protection function according to claim 2, characterized in that: Four L-shaped second protective steel pipes are arranged at the lower end of the first optical fiber fusion box, one end of each second protective steel pipe is laid to the bottom of the first optical fiber fusion box, and the other end is laid to the cable trench area after being buried underground; a first protective trough box is arranged below the first optical fiber fusion box, and the four L-shaped second protective steel pipes all pass through the first protective trough box; the four polarization-maintaining optical cables output from the first optical fiber fusion box are all sheathed with a second stainless steel corrugated tube, and each polarization-maintaining optical cable sheathed with the second stainless steel corrugated tube passes through the corresponding second protective steel pipe and is connected to the cable trough box in the cable trench area.
4. The all-optical fiber current transformer system with optical cable protection function according to claim 1, characterized in that: The AC field all-fiber current transformer includes an A-phase primary body, a B-phase primary body, a C-phase primary body, a second support frame and a second optical fiber fusion box. The A-phase primary body, the B-phase primary body, the C-phase primary body and the second support frame are all installed on the ground, and the second optical fiber fusion box is installed on the second support frame; a third protective steel pipe is arranged under each phase primary body, one end of the third protective steel pipe is laid to the corresponding primary body, and the other end enters the ground and is laid under the second optical fiber fusion box; the self-contained pigtail of each phase primary body is sleeved with a third stainless steel corrugated tube, and each self-contained pigtail cable sleeved with the third stainless steel corrugated tube is connected to the second optical fiber fusion box after passing through the corresponding third protective steel pipe as a whole.
5. The all-optical fiber current transformer system with optical cable protection function according to claim 4, characterized in that: Three fourth protective steel pipes and four L-shaped fifth protective steel pipes are arranged at the lower end of the second optical fiber fusion box, one end of each fourth protective steel pipe is laid to the bottom of the second optical fiber fusion box, and the other end is laid to the corresponding third protective steel pipe after being buried underground, and one end of each fifth protective steel pipe is laid to the bottom of the second optical fiber fusion box, and the other end is laid to the cable trench area after being buried underground; a second protective trough box is arranged at the bottom of the second optical fiber fusion box, and the four L-shaped fifth protective steel pipes all pass through the second protective trough box; the self-contained tail cables led out from the primary body of each phase pass through the corresponding third protective steel pipe and fourth protective steel pipe in turn and are connected to the second optical fiber fusion box; the four polarization-maintaining optical cables output from the second optical fiber fusion box are all sheathed with fourth stainless steel corrugated tubes, and each polarization-maintaining optical cable sheathed with the fourth stainless steel corrugated tube is connected to the optical cable trough box in the cable trench area after passing through the corresponding fifth protective steel pipe.
6. The all-fiber current transformer system with optical cable protection function according to claim 1, characterized in that: The optical cable trough box is arranged below the cable trench area pipeline and is placed close to the inner side of the wall; an L-shaped fireproof partition is arranged on the outer side of the optical cable trough box to enclose the optical cable trough box in the space formed by the fireproof partition and the pipeline wall.
7. The all-fiber current transformer system with optical cable protection function according to claim 6, characterized in that: The polarization-maintaining optical cable from the pipeline entering the cable trench area to the optical cable trough box is arranged close to the pipeline wall, and a fifth stainless steel corrugated tube is provided on this section of the polarization-maintaining optical cable.
8. The all-fiber current transformer system with optical cable protection function according to claim 1, characterized in that: A plurality of protective clamps are arranged in the vertical shaft area, and the polarization-maintaining optical cable is tightened and fixed in the vertical shaft area by the protective clamps, and a rubber pad is arranged on the inner side of each protective clamp.
9. The all-fiber current transformer system with optical cable protection function according to claim 8, characterized in that: Each protective clamp is set at an interval of 50±5cm.
10. The all-fiber current transformer system with optical cable protection function according to claim 1, characterized in that: The control room area is provided with a third protection slot box, and the polarization-maintaining optical cables located in the control room area all pass through the third protection slot box, and the inner surface of the third protection slot box is provided with a shock-absorbing pad.