CN205304202U - A high-voltage cable cross-connection box with built-in on-line monitoring device - Google Patents

Abstract

The utility model discloses an interior high tension cable cross-connection box of establishing on-line monitoring device, the box is inside including three coaxial cable 1, coaxial cable's upper portion be equipped with inner core connector 11, the lower part is equipped with outer core connector 15, its characterized in that: and a sheath current monitoring CT12, a partial discharge monitoring high-frequency CT13 and a partial discharge monitoring phase CT14 are arranged on the core wire between the inner core connector 11 and the outer core connector 15 of each coaxial cable 1. The utility model discloses an on-line monitoring device in high tension cable alternately interconnected case's sensitivity is high, and is not fragile, long service life.

Description

A high-voltage cable cross-connection box with built-in on-line monitoring device

technical field

The utility model relates to a high-voltage cable cross-connection box, in particular to a high-voltage cable cross-connection box with an on-line monitoring device inside.

Background technique

The metal sheath of high-voltage transmission cables usually adopts a segmented cross-interconnection transposition method to reduce the induced voltage on the metal sheath, thereby reducing the induced current flowing on the metal sheath. For this reason, the high-voltage cables need to be segmented, and each three consecutive sections of cables are connected by intermediate joints to form a cross-connection section; the metal sheaths on both sides of the intermediate joint in one cross-connection section are connected to two cross-connection boxes through coaxial cables. Inside, the cross-transposition is realized; the metal sheaths on both sides of the cross-interconnection section are connected to the ground grid through the ground wire. Due to cable quality, installation or aging and other reasons, defective cables and their intermediate joints are prone to partial discharge during high-voltage operation. This partial discharge phenomenon will aggravate the aging of the cable insulation layer, causing the insulation of the cable to decrease or disappear, which is likely to cause serious electrical accidents, lead to large-scale power outages, and cause major economic losses. In order to ensure the safe operation of high-voltage cables, it is necessary to carry out live partial discharge detection on high-voltage cables in operation, and carry out live measurement of the metal sheath current on the grounding wires on both sides of the cross-connection section.

The online monitoring devices currently used are mostly installed in the external natural environment where the high-voltage cable equipment is laid. After long-term exposure to the sun and rain, there are disadvantages such as low sensitivity of the online monitoring device, easy damage by moisture and other factors, and short service life.

Utility model content

The technical problem to be solved by the utility model is to provide a high-voltage cable cross interconnection box with an on-line monitoring device inside. The on-line monitoring device has high sensitivity, is not easy to be damaged, and has a long service life.

To solve the problems of the technologies described above, the technical solution of the utility model is as follows:

A high-voltage cable cross-connection box with an online monitoring device inside. The box includes three coaxial cables 1. The upper part of the coaxial cable is provided with an inner core connector 11, and the lower part is provided with an outer core connector 15. It is characterized in that: the core line between the inner core connector 11 and the outer core connector 15 of each coaxial cable 1 is provided with a sheath current monitoring CT12, a partial discharge monitoring high frequency CT13 and a partial discharge monitoring phase CT14 .

Preferably, the sheath current monitoring CT12, the partial discharge monitoring high-frequency CT13, and the partial discharge monitoring phase CT14 are respectively fixed on the insulating plate 4 that is insulated from each other.

Preferably, the box body is provided with a partial discharge monitoring device outlet port 2 and a sheath current monitoring device outlet port 3, and the transmission lines of the partial discharge monitoring high frequency CT13 and partial discharge monitoring phase CT14 are fixed on the The bottom of the box is then connected to the outlet port 2 of the partial discharge monitoring device; the transmission line of the sheath current monitoring CT12 is fixed at the bottom of the box through a wire slot, and then connected to the outlet port 3 of the sheath current monitoring device.

Preferably, the outlet port 2 of the partial discharge detection device and the outlet port 3 of the sheath current monitoring device are provided with sealed and waterproof structures.

The utility model has the following beneficial effects:

(1) Set the partial discharge on-line monitoring equipment in the cross interconnection box to avoid the shortcomings of low sensitivity, easy damage and short service life of the detection equipment due to long-term placement in the natural environment;

(2) Make full use of the existing space inside the cross-connection box, without changing the structure of the existing cross-connection box;

(3) The outlet port of the partial discharge detection device and the outlet port of the sheath current monitoring device are equipped with a sealed waterproof structure, which effectively avoids instrument damage caused by rainwater entering the cross-connection box.

Description of drawings

Below in conjunction with accompanying drawing and specific embodiment, the utility model is further described:

Fig. 1 is the structural representation of the utility model;

Fig. 2 is a structural schematic diagram of a coaxial cable of the present invention.

Reference signs: 1-coaxial cable; 2-outlet port of partial discharge monitoring device; 3-outlet port of sheath current monitoring device; 4-insulating plate; 11-inner core connector; 12-sheath current monitoring CT; 13 -High-frequency CT for partial discharge monitoring; 14-Phase CT for partial discharge monitoring; 15-Outer core connector.

detailed description

As shown in Figures 1 to 2, in a preferred embodiment of the present utility model, the inside of the box body of the high-voltage cable cross-connection box with on-line monitoring device includes three coaxial cables 1, and the upper part of the coaxial cable An inner core connector 11 is provided, and an outer core connector 15 is provided at the lower part, and the core wires between the inner core connector 11 and the outer core connector 15 of each coaxial cable 1 are arranged sequentially from top to bottom A, B, C three-phase sheath current monitoring CT12, partial discharge monitoring high frequency CT13 and partial discharge monitoring phase CT14, six transmission lines of partial discharge monitoring high frequency CT13 and partial discharge monitoring phase CT14 on three coaxial cables 1 through the card The trunking assembly is fixed at the bottom of the cross interconnection box and converged into one transmission cable, which is connected to the outlet port 2 of the partial discharge monitoring device; the three coaxial cables 1 are A, B, C three-phase partial discharge monitoring phase CT12 three The transmission lines are fixed at the bottom of the cross-interconnection box through the cable slot assembly, and converged into a transmission cable, which is connected to the outlet port 3 of the sheath current monitoring device. The high-voltage cable cross-connection box of this embodiment adopts "A coaxial cable inner core connects B coaxial cable outer core, B coaxial cable inner core connects C coaxial cable outer core, C coaxial cable inner core connects A coaxial cable The way of "outer core" constitutes a cross interconnection structure. However, in other embodiments, other cross-interconnection structures can also be used, such as making A coaxial cable inner core connect C coaxial cable outer core, B coaxial cable inner core connect A coaxial cable outer core, C The inner core of the coaxial cable is connected to the outer core of the coaxial cable of B.

The sheath current monitoring CT12, partial discharge monitoring high-frequency CT13, and partial discharge monitoring phase CT14 are respectively fixed on three insulating plates 4.

The outlet port 2 of the partial discharge detection device and the outlet port 3 of the sheath current monitoring device are provided with sealed and waterproof structures.

When in use, first install the components in the cross-connection box. Pass the inner core of the coaxial cable sequentially through the sheath current monitoring CT12, partial discharge monitoring high-frequency CT13, and partial discharge monitoring phase CT14. Then, the inner and outer cores of the three coaxial cables 1 are respectively connected to the inner core connector 11 and the outer core connector 15 . Fix the sheath current monitoring CT12, the partial discharge monitoring high-frequency CT13, and the partial discharge monitoring phase CT14 to the three insulating plates 4 respectively. First connect the transmission line of partial discharge monitoring CT13 and partial discharge monitoring phase CT14 to the waterproof connector, and pass through the outlet port 2 of the partial discharge monitoring device, then fix the transmission line in the clamping slot at the bottom of the cross interconnection box, and finally the transmission line It is connected with partial discharge monitoring CT13 and partial discharge monitoring phase CT14. Similarly, first connect the transmission line of the sheath current monitoring CT12 to the waterproof connector, and pass through the outlet port 3 of the sheath current monitoring device, then fix the transmission line in the clamping slot at the bottom of the cross-connection box, and finally connect the transmission line to the sheath Set of current monitoring CT12 connections.

Claims (4)

1. set the cross interconnected case of high tension cable of on-Line Monitor Device in one kind, box house includes three coaxial cables (1), the top of described coaxial cable (1) is provided with inner core union joint (11), bottom is provided with outer core union joint (15), it is characterised in that: the heart yearn between inner core union joint (11) and the outer core union joint (15) of every described coaxial cable (1) is provided with sheath current monitoring CT(12), partial discharge monitoring high frequency CT(13) and partial discharge monitoring phase place CT(14).

2. according to claim 1, set the cross interconnected case of high tension cable of on-Line Monitor Device, it is characterised in that: described sheath current monitoring CT(12), partial discharge monitoring high frequency CT(13), partial discharge monitoring phase place CT(14) be individually fixed on the insulation board (4) of mutually insulated.

3. according to claim 1 and 2, set the cross interconnected case of high tension cable of on-Line Monitor Device, it is characterized in that: the casing of the cross interconnected case of described high tension cable is provided with partial discharge monitoring device outlet port (2) and sheath current monitoring device outlet port (3), described partial discharge monitoring high frequency CT(13) and partial discharge monitoring phase place CT(14) transmission line be fixed on bottom by cable clamping interface, be then attached to partial discharge monitoring device outlet port (2); Described sheath current monitoring CT(12) transmission line be fixed on bottom by cable clamping interface, be then attached to sheath current monitoring device outlet port (3).

4. according to claim 3, set the cross interconnected case of high tension cable of on-Line Monitor Device, it is characterised in that: local discharge detection device outlet port (2) and sheath current monitoring device outlet port (3) are provided with hermetic water-proof structure.