CN216794597U - High-voltage power supply relay protection system of tower crane - Google Patents

Abstract

The utility model belongs to the technical field of tower cranes, and in particular relates to a high-voltage power supply relay protection system for tower cranes, comprising a high-voltage power supply cabinet for high-voltage power supply and a box-type substation, wherein the high-voltage power supply cabinet mainly includes an isolation switch, a vacuum circuit breaker and a zero sequencer Current transformer; The high-voltage incoming unit of the box-type substation is mainly a combination of load switches and fuses, and fuses and voltage/current transformers are set between the isolation switches and vacuum circuit breakers of the high-voltage power supply cabinet. Between the zero-sequence current transformers, a parallel grounding knife switch and a lightning arrester are set to the ground, which cooperate with the microcomputer comprehensive protection device installed in the high-voltage power distribution cabinet for protection; the front-end of the load switch of the high-voltage incoming unit is equipped with a lightning arrester, which is located at the fuse. Set the grounding switch. The utility model solves the problem of safety protection when a large or super large tower crane adopts high voltage power supply through the relay protection design of the high voltage power supply cabinet and the box-type substation in the high voltage power supply system.

Description

A high-voltage power supply relay protection system for tower cranes

technical field

The utility model belongs to the technical field of tower cranes, in particular to a high-voltage power supply relay protection system for tower cranes.

Background technique

In the existing tower crane industry, the low-voltage three-phase AC 380V/400V power supply mode is generally used for power supply, but for large or super-large tower cranes, due to the large power required, if the low-voltage three-phase AC 380V/400V power supply mode is used, the single-phase Due to the large current carried by the cable, the nominal cross-section of the single-phase cable may even reach more than 300 square millimeters, which is expensive and causes great difficulties in manufacturing and on-site installation and construction. Large or super-large tower cranes need to use high-voltage power supply due to their large power requirements to reduce the current and reduce the cable diameter of the cable, which puts forward higher requirements for the safety protection of the overall high-voltage power supply system of the tower crane.

Utility model content

In view of the above problems, the utility model provides a high-voltage power supply relay protection system for tower cranes.

For realizing the above-mentioned purpose, the utility model adopts the following technical scheme:

A high-voltage power supply relay protection system for a tower crane, including a ground high-voltage power supply cabinet for high-voltage power supply, a box-type substation on the top platform of the tower crane and a high-voltage power supply cable, wherein the high-voltage power supply cabinet mainly includes an isolation switch, a vacuum circuit breaker and a zero sequencer Current transformer; the high-voltage incoming line unit of the box-type substation is mainly a combination of load switch and fuse II, and fuse I and voltage\current transformers are arranged between the isolation switch and vacuum circuit breaker of the high-voltage power supply cabinet , between the vacuum circuit breaker and the zero-sequence current transformer, a parallel grounding knife switch and arrester I are set to the ground to cooperate with the microcomputer comprehensive protection device installed in the high-voltage power supply cabinet for protection; the load switch of the high-voltage incoming unit The front end is equipped with a lightning arrester II, and a grounding switch is set at the fuse II.

Further, over-temperature protection is also provided in the box-type substation: the transformer unit is equipped with an automatic temperature control device.

Further, low-voltage protection is also provided in the box-type substation: the low-voltage main switch of the low-voltage power consumption unit adopts a frame circuit breaker, and an intelligent controller is installed.

Further, the protection system is also provided with external protection.

Further, the external protection is power supply cable protection: the power supply cable adopts multi-layer protection cables, and is provided with separate lightning protection and grounding cables.

Further, the external protection is that the box-type substation and the high-voltage power supply cabinet have waterproof and anti-corrosion functions, and meet the high-voltage 5-proof standard.

Further, the grounding resistance set for the external protection for the tower crane and its electrical appliances should not be greater than 4 ohms, or when multiple repeated groundings are used, the grounding resistance should not be greater than 10 ohms.

The utility model proposes a high-voltage power supply relay protection system for tower cranes, which solves the problem of safety protection when large or super-large tower cranes use high-voltage power supply through the design of relay protection for high-voltage power supply cabinets and box-type substations in the high-voltage power supply system. And through the high-voltage cables, tower crane body and electrical equipment, etc., to improve the protection of the overall high-voltage power supply system.

Description of drawings

Figure 1: Diagram of tower crane high voltage power supply relay protection system.

Detailed ways

The present utility model will be further described below in conjunction with the accompanying drawings and embodiments, but not as a basis for limiting the present utility model.

The utility model proposes a high-voltage power supply relay protection system for tower cranes. Through the design of the relay protection for the ground high-voltage power supply cabinet 2 and the box-type substation 1 on the top platform of the tower crane, it solves the problem of safety when large or super-large tower cranes use high-voltage power supply. protection issues. The specific protection measures are as follows:

As shown in Figure 1, 1) Ground high-voltage power supply cabinet protection: The high-voltage power supply cabinet 2 is installed at the bottom of the tower, and mainly includes an isolation switch 21 , a vacuum circuit breaker 22 and a zero-sequence current transformer 23 . A fuse I24 and a voltage/current transformer 25 are arranged between the isolating switch 21 and the vacuum circuit breaker 22, and a parallel grounding knife switch 26 and a surge arrester I27 are arranged between the vacuum circuit breaker 22 and the zero-sequence current transformer 23. Cooperate with the integrated microcomputer protection device in the high-voltage power supply cabinet 2, and complete the protection of short circuit, disconnection, over-current, over-voltage, zero-sequence over-current, ground fault, lightning strike, etc. by comprehensively setting parameters.

2) High-voltage protection of box-type substation: The high-voltage incoming line unit 11 of box-type substation 1 is a combined electrical appliance of load switch 111 and fuse II 112. A lightning arrester II 113 is provided at the front end of the load switch 111, and a grounding switch 114 is provided at the fuse II 112 to realize the secondary protection of short circuit, overcurrent, overload and lightning strike on the high voltage side of the transformer 121.

The box-type substation 1 is also provided with:

3) Over-temperature protection of box-type substation: The transformer unit 12 is equipped with an automatic temperature control device for ventilation and heat dissipation;

4) Low-voltage protection of box-type substations: The low-voltage main switch 131 of the low-voltage power consumption unit 13 adopts a frame circuit breaker, is equipped with an intelligent controller, and has long-delay, short-delay, and instantaneous current protection.

There are also external protections in the tower crane high-voltage power supply relay protection system:

5) Power supply cable protection: Power supply cable 3 adopts multi-layer protection cable, and has a separate cable for lightning protection and grounding.

6) The ground high-voltage power supply cabinet and the box-type substation on the top platform of the tower crane have waterproof and anti-corrosion functions, and meet the high-voltage 5-proof conditions.

7) Protection of the tower crane body: the main structure of the tower crane, the metal casing of the motor base and all electrical equipment, and the metal protection tube of the wire should be reliably grounded, and the grounding resistance should not be greater than 4 ohms. The grounding resistance should be no more than 10 ohms.

Claims (7)

1. A tower crane high-voltage power supply relay protection system, comprising a ground high-voltage power supply cabinet (2) for high-voltage power supply, a tower crane top platform box-type substation (1) and a high-voltage power supply cable (3), wherein the high-voltage power supply cabinet (2) It mainly includes an isolating switch (21), a vacuum circuit breaker (22) and a zero-sequence current transformer (23); the high-voltage incoming unit (11) of the box-type substation (1) is mainly a load switch (111) A combined electrical appliance with fuse II (112), which is to be characterized in that: between the isolating switch (21) and the vacuum circuit breaker (22) of the high-voltage power supply cabinet (2), a fuse I (24) and a voltage/current Transformer (25), between the vacuum circuit breaker (22) and the zero-sequence current transformer (23), a grounding knife switch (26) and a lightning arrester I (27) are arranged in parallel to the ground, and are arranged in the high-voltage power supply cabinet (2). The microcomputer comprehensive protection device in ) is matched; the front end of the load switch (111) of the high-voltage incoming unit (11) is equipped with a lightning arrester II (113), and a grounding switch (114) is provided at the fuse II (112). 2. A high-voltage power supply relay protection system for tower cranes according to claim 1, which is to be characterized in that: the box-type substation (1) is also provided with over-temperature protection: the transformer unit (12) is configured with an automatic temperature control device. 3. A high-voltage power supply relay protection system for tower cranes according to claim 1, which is to be characterized in that: the box-type substation (1) is also provided with low-voltage protection: the low-voltage protection of the low-voltage power consumption unit (13) The main switch (131) adopts a frame circuit breaker and is provided with an intelligent controller. 4 . The high-voltage power supply relay protection system for tower cranes according to claim 1 , wherein the protection system is further provided with external protection. 5 . 5. A high-voltage power supply relay protection system for tower cranes according to claim 4, wherein the external protection is power supply cable protection: the power supply cable (3) adopts multi-layer protection cables, and is provided with a separate protection cable. Lightning and ground cables. 6. A high-voltage power supply relay protection system for tower cranes according to claim 4, wherein the external protection is that the box-type substation (1) and the high-voltage power supply cabinet (2) have waterproof and anti-corrosion functions, And meet the high-voltage 5-proof standard. 7. The high-voltage power supply relay protection system for tower cranes according to claim 4, wherein the grounding resistance provided by the external protection for the tower crane and its electrical appliances should be no greater than 4 ohms, or multiple repetitions are used. When grounding, the grounding resistance should not be greater than 10 ohms.

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