CN206004138U - A kind of high-tension switch cabinet relay bungalow earth protective device - Google Patents

Abstract

The utility model discloses a grounding protection device for a relay room of a high-voltage switch cabinet, which comprises a bus bar and a bus bar grounding device. The bus bar grounding device includes a first side plate and a second side plate, and the bus bar is located on the first side plate and the second Between the side plates, both the first side plate and the second side plate are grounded; the bus bar is also connected to the arc extinguishing protection device through the lead wire, and the arc extinguishing protection device includes a high-voltage isolating switch. One end of the high-voltage isolating switch is connected to the bus bar, and the other end is in turn Connected with a voltage transformer, the voltage transformer is connected to the input end of the central processing unit, the output end of the central processing unit is connected to the controlled end of the three-phase AC contactor, the three-phase AC contactor is connected to the high-voltage isolation switch, and the three-phase AC contactor The device is also grounded through the reactor and the current transformer in turn. The utility model utilizes the grounding protection device to realize reliable grounding of the bus bar, and realizes good arc extinguishing through the arc extinguishing protection device, thereby improving the safety and reliability of the high-voltage switchgear operation.

Description

A grounding protection device for a high-voltage switchgear relay room

technical field

The utility model relates to the technical field of high-voltage switchgear protection, in particular to a grounding protection device for a relay chamber of a high-voltage switchgear.

Background technique

With the wide application of high-voltage switchgear, its safety has received more and more attention. When using high-voltage switchgear, it generally needs to be grounded to prevent insulation damage or accidental personal injury.

The traditional grounding protection line is mostly connected to the cabinet through the secondary terminal, but because the cabinet is easy to rust, it is easy to cause poor grounding contact and excessive grounding resistance, and the current will pass through the human body when leakage occurs, causing electric shock danger. In order to solve the problem that the cabinet is easy to rust, the existing high-voltage switchgear adopts bus bar grounding. This grounding method is not affected by the cabinet body, but the existing bus bar is generally placed on one side of the bus duct, but The grounding device in this way only protects one side of the bus duct, and does not protect the other three sides. When a leakage accident occurs, the leakage current on the bus bar can only flow into the ground through the bus duct on one side, and the current on the other three sides passes through The equipment casing is indirectly led to the earth. When the casing is rusted, it is still prone to electric shock accidents.

In addition, when a ground short circuit occurs in a high-voltage switchgear, a large arc will often be generated at the fault point, and overvoltage will be generated, threatening the equipment with weak insulation. The busbar grounding method is difficult to detect the weak signal of high-resistance grounding faults, and generally cannot judge the early symptoms of insulation aging and other faults, and cannot meet the needs of limiting and protecting various overvoltages that occur in high-voltage switchgear.

Utility model content

The purpose of the utility model is to provide a high-voltage switchgear relay room grounding protection device, which can realize reliable grounding of the high-voltage switchgear and improve the safety and reliability of the high-voltage switchgear operation.

In order to achieve the above object, the utility model adopts the following technical solutions:

A grounding protection device for a relay room of a high-voltage switchgear, which is installed in the relay room of a high-voltage switchgear, and includes a bus bar and a grounding device for the bus bar. The grounding device for the bus bar includes a first side plate and a second side plate, and the bus bar is located at the second Between one side plate and the second side plate, the first side plate is arranged parallel to the bus bar, the first side plate includes a left side plate and a right side plate, the second side plate is arranged perpendicular to the bus bar, and the second side plate It includes an upper side plate and a lower side plate, the first side plate and the second side plate are both grounded; the first side plate is provided with an outlet hole, and a lead wire is arranged in the outlet hole, and the bus bar is connected to the An arc protection device, the arc extinguishing protection device includes a high-voltage isolating switch, one end of the high-voltage isolating switch is connected to the busbar, and the other end is sequentially connected to the first high-voltage fuse and a voltage transformer, and the voltage transformer is connected to the input end of the central processing unit , the output end of the central processing unit is connected to the controlled end of the three-phase AC contactor, and the three-phase AC contactor is connected to the high-voltage isolating switch through the second high-voltage fuse, and the three-phase AC contactor is also connected to the reactor and the current transformer in turn. grounded.

Radiating fins are arranged on the outer side of the first side plate.

The first side plate and the second side plate are fixedly connected by bolts.

The high voltage isolating switch is also grounded through a voltage protector.

An ammeter is connected in parallel with the current transformer.

The utility model has the following advantages:

(1) The first side plate and the second side plate are arranged around the busbar, and both the first side plate and the second side plate are grounded. When a leakage accident occurs in the high-voltage switchgear, the leakage current in the high-voltage switchgear is guaranteed to be directly introduced into the Earth, grounding protection is comprehensive and reliable;

(2) There is a heat sink on the first side plate, and the heat generated by the bus bar is taken away through the heat sink, so as to prevent the conductive performance of the bus bar from being overheated and cause a decline in heat dissipation, and the heat dissipation effect is good;

(3) The bus bar is connected with an arc-extinguishing protection device through the lead-out line. When a short-circuit fault occurs in the high-voltage switchgear, the reactor is used to limit the fault phase voltage and current, and the fault phase is grounded through the three-phase AC contactor to achieve complete protection. The purpose of arc suppression improves the safety and reliability of high-voltage switchgear operation;

(4) The over-current protector is used to limit the operating over-voltage, not affected by the voltage waveform, the over-voltage protection value is accurate, and the protection performance is excellent.

The utility model utilizes the grounding protection device to realize reliable grounding of the bus bar, and realizes good arc extinguishing through the arc extinguishing protection device, can realize reliable grounding of the high-voltage switchgear, and improves the safety and reliability of the high-voltage switchgear operation.

Description of drawings

Fig. 1 is the structural representation of the grounding device of the bus bar described in the utility model;

Fig. 2 is an electrical schematic diagram of the arc extinguishing protection device of the present invention.

detailed description

As shown in Figure 1 and Figure 2, the utility model is set in a high-voltage switchgear, including a bus bar 1 and a bus bar grounding device, the bus bar grounding device includes a first side plate and a second side plate, and the bus bar 1 is located in the first Between the side plate and the second side plate, the first side plate is arranged parallel to the bus bar 1, the first side plate includes a left side plate 3 and a right side plate 2, the second side plate is arranged perpendicular to the bus bar 1, and the second side The plate includes an upper side plate 7 and a lower side plate 4, the first side plate and the second side plate are fixedly connected by bolts 5, and both the first side plate and the second side plate are grounded to ensure that the leakage current of the live parts can directly flow into the ground , comprehensive grounding protection, the outside of the left side board 3 and the right side board 2 are provided with cooling fins 6, the cooling fins 6 are used to take away the heat generated by the busbar 1, and prevent the conductive performance of the busbar 1 from decreasing due to overheating.

There is an outlet hole on the first side plate, and a lead wire 8 is arranged in the wire outlet hole. The bus bar 1 is connected to the arc extinguishing protection device through the lead wire 8. The arc extinguishing protection device includes a high-voltage isolation switch QF, and one end of the high-voltage isolation switch QF is connected to the bus bar. Row 1, the other end is connected with the first high-voltage fuse FU1 and the voltage transformer PT in turn, the voltage transformer PT is connected with the input end of the central processing unit CPU, and the output end of the central processing unit CPU is connected with the receiving end of the three-phase AC contactor KM At the control end, the three-phase AC contactor KM is connected to the high-voltage isolating switch QF through the second high-voltage fuse FU2, and the three-phase AC contactor KM is also grounded through the reactor L and the current transformer CT in turn. In this embodiment, the current mutual inductance An ammeter A is connected in parallel to the transformer CT, and the other end of the high-voltage isolation switch QF is also grounded through the voltage protector U>, where U> is the symbol of the overvoltage protector and has no special meaning.

Under normal circumstances, the three-phase AC contactor KM is disconnected. When a leakage fault occurs in the high-voltage switchgear, the leakage current on the bus bar 1 is introduced into the ground through the first side plate and the second side plate, and the reliable grounding of the bus bar 1 is realized. ; When a grounding short-circuit fault occurs in the high-voltage switchgear, the central processing unit CPU outputs a control signal to the three-phase AC relay KM, and the bus bar 1 is grounded through the reactor L and the current transformer CT, and the fault phase voltage and current are limited by the reactor CT , At the same time, the faulty phase of the three-phase AC relay KM is connected to achieve the purpose of complete arc suppression and improve the safety and reliability of the high-voltage switchgear operation.

The utility model uses the grounding protection device to realize reliable grounding of the bus bar 1, and realizes good arc extinguishing through the arc extinguishing protection device, can realize reliable grounding of the high-voltage switchgear, and improves the safety and reliability of the high-voltage switchgear operation.

Claims (5)

1. A grounding protection device for a high-voltage switchgear relay room, which is arranged in a relay room of a high-voltage switchgear, and is characterized in that: it includes a bus bar and a bus bar grounding device, and the bus bar grounding device includes a first side plate and a second side The bus bar is located between the first side plate and the second side plate, the first side plate is arranged parallel to the bus bar, the first side plate includes a left side plate and a right side plate, and the second side plate is perpendicular to the bus bar Setting, the second side plate includes an upper side plate and a lower side plate, the first side plate and the second side plate are both grounded; the first side plate is provided with an outlet hole, and a lead wire is arranged in the outlet hole, and the busbar The row is connected to the arc extinguishing protection device through the lead wire, and the arc extinguishing protection device includes a high-voltage isolating switch. One end of the high-voltage isolating switch is connected to the bus bar, and the other end is connected to the first high-voltage fuse and a voltage transformer in sequence. The voltage transformer and the central The input ends of the processors are connected, and the output ends of the central processing unit are connected to the controlled end of the three-phase AC contactor. The reactor and the current transformer are grounded. 2. A grounding protection device for a relay room of a high-voltage switchgear as claimed in claim 1, wherein a cooling fin is arranged on the outer side of the first side plate. 3. A grounding protection device for a relay room of a high-voltage switchgear according to claim 2, wherein the first side plate and the second side plate are fixedly connected by bolts. 4. A grounding protection device for a relay room of a high-voltage switchgear as claimed in claim 3, wherein the high-voltage isolating switch is also grounded through a voltage protector. 5. A grounding protection device for a relay room of a high-voltage switchgear as claimed in claim 4, wherein an ammeter is connected in parallel to the current transformer.