High-voltage power supply grounding fault processing system

Abstract

The invention discloses a high-voltage power supply grounding fault processing system which comprises a zero sequence voltage transformer, a plurality of fault removal modules capable of independently controlling removal of output sub-lines of a high-voltage power supply cabinet, and a line selection device used for selecting fault lines in the output sub-lines of the high-voltage power supply cabinet. Each fault removal module is provided with a zero sequence current transformer, a small current line selection tripping pressing plate, a relay protection device and a circuit breaker. When one path of the output sub-line of the high-voltage power supply cabinet is grounded and short-circuited, the line selection device can judge the grounded sub-line according to the received zero-sequence voltage and a plurality of zero-sequence currents, and then transmits a low-current fault action signal to the low-current line selection tripping pressing plate of the corresponding fault removal module to trip off a circuit breaker. The output sub-line of the high-voltage power supply cabinet is automatically cut off. The high-voltage power supply ground fault processing system can automatically identify and remove the ground fault of the high-voltage power supply system, improve the fault processing speed and ensure the operation safety of the high-voltage power supply system.

Description

Technical Field

[0001] The invention relates to the technical field of high-voltage power supply, and in particular to a high-voltage power supply grounding fault processing system. Background Art

[0002] In recent years, with the increase of electrical equipment used in industrial production, the voltage of the power supply system in industrial production plants has also increased. The voltage of the existing power supply system in industrial production plants is usually 6kV-10kV.

[0003] The grid capacity of the high-voltage power supply system is large, but it also has a large grounding current. For a high-voltage power supply system with single-phase grounding, when a single-phase grounding fault occurs, since no short-circuit current is generated, the line voltage is still symmetrical and does not affect normal power supply. According to relevant regulations, the system is allowed to continue to operate for 1 to 2 hours. However, at this time, the non-fault relative ground voltage rises to the line voltage, which is easy to cause system resonance. Long-term operation with faults is very likely to cause arc grounding, forming a two-point grounding fault, causing system overvoltage, and damaging the insulation of power grid equipment. When it reaches a certain level, it will cause PT explosion or insulator flashover.

[0004] In order to avoid the system overvoltage problem caused by single-phase grounding fault, the traditional method is to use the wire pulling method to cut off the fault line. The wire pulling method uses the AC insulation inspection device of the substation to send out a grounding signal, and then the on-duty personnel take the method of sequentially pulling the switch according to the nature of the load to find the fault line, and cut off the fault line after transferring the load. Although the wire pulling method can ensure correctness, it is slow and extremely unfavorable to the reliability of power supply. Especially for important loads in the factory area, direct line pulling not only affects production but also poses a great threat to personal safety. In addition, the fault handling speed is slow, which is easy to cause the accident to expand and affect the safe and stable operation of the system. The method of using the line selection device to cut off the fault line can quickly and accurately locate the fault point after the grounding fault occurs in the line, and then manually cut off the fault. Compared with the traditional wire pulling method, the efficiency is greatly improved, but it also takes a certain amount of time from the occurrence of the fault to the transmission to the monitoring background, and then to the maintenance personnel to cut off the fault. During this period of time, the fault still exists and may cause the fault to expand at any time, still affecting the safe operation of the power supply system. Summary of the invention

[0005] Based on this, it is necessary to provide a high-voltage power supply grounding fault processing system to address the above technical problems, which can automatically identify and cut off the grounding fault of the high-voltage power supply system, improve the fault processing speed, and ensure the safe operation of the high-voltage power supply system.

[0006] The present invention provides a high-voltage power supply grounding fault processing system, comprising a zero-sequence voltage transformer arranged in a busbar PT cabinet of a high-voltage power supply cabinet, a plurality of fault removal modules capable of independently controlling the removal of an output sub-line of a high-voltage power supply cabinet, and a line selection device for selecting a faulty line among the output sub-lines of a plurality of high-voltage power supply cabinets;

[0007] The zero-sequence voltage transformer is electrically connected to the line selection device;

[0008] The positive pole of the start-stop control circuit of each fault removal module is electrically connected to a dry contact of a channel of the line selection device;

[0009] Each fault clearing module includes:

[0010] A zero-sequence current transformer, which is sleeved on the outside of the output sub-line of the high-voltage power supply cabinet controlled by the fault removal module, and is electrically connected to the line selection device;

[0011] A small current line selection tripping pressure plate, the input end of the small current line selection tripping pressure plate is electrically connected to another dry contact of a channel where a dry contact connected to the positive pole of the start-stop control circuit of the fault removal module where the small current line selection tripping pressure plate is located in the line selection device;

[0012] A relay protection device having two groups of relay interfaces, wherein the output end and the input end of the first group of relay interfaces are respectively connected to the positive and negative poles of the start-stop control circuit of the fault removal module, and the output end of the small current line selection tripping pressure plate is electrically connected to the input end of the second group of relay interfaces;

[0013] The circuit breaker is connected in series to the output sub-line of the high-voltage power supply cabinet controlled by the circuit breaker, the input end of the tripping coil channel of the circuit breaker is electrically connected to the output end of the second group of relay interfaces, and the output end of the tripping coil channel of the relay is electrically connected to the negative pole of the start-stop control circuit of the fault removal module.

[0014] In one of the embodiments, the fault removal module is also provided with a circuit protection device and a circuit protection tripping pressure plate, the input end of the circuit protection device is electrically connected to the positive pole of the start-stop control circuit of the fault removal module, the input end of the circuit protection tripping pressure plate is electrically connected to the output end of the circuit protection device, and the output end of the circuit protection tripping pressure plate is electrically connected to the input end of the second group of relay interfaces.

[0015] In one embodiment, the fault removal module is further provided with a first indicator light and a second indicator light of different luminous colors, and the circuit breaker is provided with a first switch channel which is opened and closed synchronously with the trip coil channel switch, and a second switch channel which is opened and closed asynchronously with the trip coil channel switch;

[0016] One end of the first indicator light is electrically connected to the input end of the first switch channel, one end of the second indicator light is electrically connected to the input end of the second switch channel, the output ends of the first switch channel and the second switch channel are both electrically connected to the negative pole of the start-stop control circuit of the fault removal module, and the other end of the first indicator light and the other end of the second indicator light are both electrically connected to the positive pole of the start-stop control circuit of the fault removal module.

[0017] Beneficial effects of the present invention: In the high-voltage power supply grounding fault processing system of the present invention, each high-voltage power supply cabinet output sub-line is controlled by a fault removal module, and the zero-sequence current transformers of all fault removal modules are connected to the line selection device. When one of the output sub-lines of the high-voltage power supply cabinet is short-circuited to ground, the line selection device can determine the grounded sub-line according to the received zero-sequence voltage and multiple zero-sequence currents, and then control the trip relay corresponding to the current sub-line through the internally set controller to transmit the small current fault action signal to the small current line selection tripping pressure plate of the corresponding fault removal module. The small current is connected to the relay protection device through the small current line selection tripping pressure plate, and then the relay protection device drives the circuit breaker tripping coil on the current high-voltage power supply cabinet output sub-line to be energized, trip the circuit breaker, and realize the automatic cutting off of the output sub-line of the high-voltage power supply cabinet. In the high-voltage power supply grounding fault processing system of the present invention, when a line grounding fault occurs, it can automatically and quickly screen and cut off the grounding fault line to avoid the expansion of the fault and effectively ensure the safe operation of the high-voltage power supply system. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 A schematic diagram of the circuit structure of a high-voltage power supply grounding fault processing system provided in an embodiment of the present invention.

[0019] Explanation of the reference numerals: 100, zero-sequence current transformer; 101, circuit protection device; 102, circuit protection tripping pressure plate; 103, small current line selection tripping pressure plate; 104, relay protection device; 105, circuit breaker; 106, first indicator light; 107, second indicator light; 200, zero-sequence voltage transformer; 300, line selection device. DETAILED DESCRIPTION

[0020] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0021] In one embodiment, Figure 1 As shown, Figure 1It is a circuit structure diagram of a high-voltage power supply grounding fault processing system provided in an embodiment of the present invention. The high-voltage power supply grounding fault processing system of this embodiment includes a zero-sequence voltage transformer 200 arranged in a busbar PT cabinet of a high-voltage power supply cabinet, a plurality of fault removal modules that can individually control the removal of an output sub-line of a high-voltage power supply cabinet, and a line selection device 300 for selecting a faulty line among the output sub-lines of a plurality of high-voltage power supply cabinets; the zero-sequence voltage transformer 200 is electrically connected to the line selection device 300.

[0022] It should be noted that the zero-sequence voltage transformer 200 arranged in the bus PT cabinet of the high-voltage power supply cabinet can collect the zero-sequence signal of the bus of the high-voltage power supply cabinet. When the output sub-line of the high-voltage power supply cabinet is grounded, the zero-sequence voltage of its bus will also change. The high-voltage power supply cabinet has one bus and multiple output sub-lines.

[0023] Specifically, the line selection device 300 in this embodiment may be, but is not limited to, a Xirui XRA-800 series line selection device 300.

[0024] The positive pole of the start-stop control circuit of each fault removal module is electrically connected to a dry contact of a channel of the line selection device 300 .

[0025] Each fault clearing module includes:

[0026] The zero-sequence current transformer 100 is sleeved on the outer side of the output sub-line of the high-voltage power supply cabinet correspondingly controlled by the fault removal module, and the zero-sequence current transformer 100 is electrically connected to the line selection device 300.

[0027] The input end of the small current line selection tripping pressure plate 103 is electrically connected to another dry contact of the channel where the dry contact connected to the positive pole of the start-stop control circuit of the fault removal module where the small current line selection tripping pressure plate 103 is located in the line selection device 300.

[0028] In this embodiment, the small current line selection tripping pressure plate 103 remains connected and can be considered to be open or closed.

[0029] The relay protection device 104 has two groups of relay interfaces, the output end and input end of the first group of relay interfaces are respectively connected to the positive and negative poles of the start-stop control circuit of the fault removal module, and the output end of the small current line selection tripping pressure plate 103 is electrically connected to the input end of the second group of relay interfaces.

[0030] Circuit breaker 105, circuit breaker 105 is connected in series to the output sub-line of the high-voltage power supply cabinet controlled by the circuit breaker 105, the input end of the tripping coil channel of the circuit breaker 105 is electrically connected to the output end of the second group of relay interfaces, and the output end of the tripping coil channel of the relay is electrically connected to the negative pole of the start-stop control circuit of the fault removal module.

[0031] In this embodiment, a fault removal module is provided on each output sub-line. Multiple fault removal modules are connected to a line selection device 300, in which a control board and multiple tripping relays are built, each tripping relay corresponds to an output sub-line, and the control board can calculate the output sub-line with ground fault according to the zero-sequence voltage of the busbar and the zero-sequence current of each output sub-line, and then control the tripping relay corresponding to the output sub-line with ground fault to send a small current fault action signal to the corresponding small current line selection tripping pressure plate 103 through the dry contact of the channel where the tripping relay is located, and then the small current signal is connected to the relay protection device 104 through the small current line selection tripping pressure plate 103, and then the relay protection device 104 drives the tripping coil of the circuit breaker 105 on the current high-voltage power supply cabinet output sub-line to be energized, and the circuit breaker 105 is tripped, so as to realize the automatic cutting off of the output sub-line of the high-voltage power supply cabinet.

[0032] In this embodiment, the high-voltage power supply grounding fault processing system can quickly screen out the faulty transmission line and quickly cut it off through the cooperation of the fault removal module and the line selection device 300, thereby avoiding the expansion of the fault and effectively ensuring the safe operation of the high-voltage power supply system.

[0033] In one embodiment, the fault removal module is also provided with a circuit protection device 101 and a circuit protection tripping pressure plate 102, the input end of the circuit protection device 101 is electrically connected to the positive pole of the start-stop control circuit of the fault removal module, the input end of the circuit protection tripping pressure plate 102 is electrically connected to the output end of the circuit protection device 101, and the output end of the circuit protection tripping pressure plate 102 is electrically connected to the input end of the second group of relay interfaces.

[0034] The function of the loop protection device 101 and the loop protection tripping pressure plate 102 is that when other faults occur in the current system circuit except the grounding fault of the output sub-cable of the high-voltage power supply cabinet, the loop protection device 101 will be activated, and the loop protection action signal will pass through the loop protection tripping pressure plate 102 and then be connected to the relay protection device 104. After the relay protection device 104 is energized, it drives the tripping coil of the circuit breaker 105 to be energized, and the circuit breaker 105 will be tripped, thereby realizing the automatic cutting off of the high-voltage power supply output sub-line.

[0035] In addition, in the high-voltage power supply grounding fault processing system of this embodiment, a main switch is provided at the positive and negative outlet ends of the start-stop control circuit of each fault removal module, respectively, for controlling the connection and disconnection of each output sub-line in the high-voltage control cabinet.

[0036] In one embodiment, the fault removal module is further provided with a first indicator light 106 and a second indicator light 107 with different luminous colors, and the circuit breaker 105 is provided with a first switch channel that is opened and closed synchronously with the trip coil channel switch, and a second switch channel that is opened and closed asynchronously with the trip coil channel switch;

[0037] One end of the first indicator light 106 is electrically connected to the input end of the first switch channel, one end of the second indicator light 107 is electrically connected to the input end of the second switch channel, the output ends of the first switch channel and the second switch channel are both electrically connected to the negative pole of the start-stop control circuit of the fault removal module, and the other end of the first indicator light 106 and the other end of the second indicator light 107 are both electrically connected to the positive pole of the start-stop control circuit of the fault removal module.

[0038] When the relay protection device 104 is energized and the tripping coil of the circuit breaker 105 is driven to be energized, the tripping coil channel switch is closed, and at the same time, the switch in the first switch channel is closed, the switch in the second switch channel is opened, and the first indicator light 106 is illuminated; when the tripping coil channel switch is opened, at the same time, the switch in the first switch channel is opened, the switch in the second switch channel is closed, and the second indicator light 107 is illuminated. The first indicator light 106 and the second indicator light 107 are used to remind the operator.

[0039] The high-voltage power supply grounding fault processing system of this embodiment can automatically and quickly cut off the grounding fault line when a line grounding fault occurs, thereby preventing the fault from expanding and reminding the operator to facilitate maintenance by the operator.

[0040] The above-mentioned embodiments only express several implementation methods of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the scope of the present invention. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the attached claims.

Claims

1. A high voltage power supply grounding fault processing system, characterized in that: It comprises a zero-sequence voltage transformer (200) arranged in a busbar PT cabinet of a high-voltage power supply cabinet, a plurality of fault removal modules capable of independently controlling the removal of an output sub-line of a high-voltage power supply cabinet, and a line selection device (300) for selecting a faulty line among a plurality of output sub-lines of the high-voltage power supply cabinet; The zero-sequence voltage transformer (200) is electrically connected to the line selection device (300); The positive pole of the start-stop control circuit of each fault removal module is electrically connected to a dry contact of a channel of the line selection device (300); Each fault clearing module includes: A zero-sequence current transformer (100), the zero-sequence current transformer (100) being sleeved on the outside of the output sub-line of the high-voltage power supply cabinet correspondingly controlled by the fault removal module, and the zero-sequence current transformer (100) being electrically connected to the line selection device (300); A small current line selection tripping pressure plate (103), the input end of the small current line selection tripping pressure plate (103) being electrically connected to another dry contact of a channel where a dry contact connected to a positive pole of a start / stop control circuit of a fault removal module where the small current line selection tripping pressure plate (103) is located in the line selection device (300); A relay protection device (104) having two groups of relay interfaces, wherein the output end and the input end of the first group of relay interfaces are respectively connected to the positive and negative poles of the start-stop control circuit of the fault removal module, and the output end of the small current line selection tripping pressure plate (103) is electrically connected to the input end of the second group of relay interfaces; A circuit breaker (105), the circuit breaker (105) is connected in series to an output sub-line of a high-voltage power supply cabinet corresponding to the circuit breaker (105) and controlled by the circuit breaker (105); an input end of a trip coil channel of the circuit breaker (105) is electrically connected to an output end of the second group of relay interfaces; and an output end of a trip coil channel of the relay is electrically connected to a negative pole of a start-stop control circuit of the fault removal module.

2. The high voltage power supply grounding fault processing system according to claim 1, characterized in that: The fault removal module is also provided with a circuit protection device (101) and a circuit protection tripping pressure plate (102); the input end of the circuit protection device (101) is electrically connected to the positive pole of the start-stop control circuit of the fault removal module; the input end of the circuit protection tripping pressure plate (102) is electrically connected to the output end of the circuit protection device (101); and the output end of the circuit protection tripping pressure plate (102) is electrically connected to the input end of the second group of relay interfaces.

3. The high voltage power supply grounding fault processing system according to claim 2, characterized in that: The fault removal module is also provided with a first indicator light (106) and a second indicator light (107) with different luminous colors, and the circuit breaker (105) is provided with a first switch channel that is opened and closed synchronously with the trip coil channel switch, and a second switch channel that is opened and closed asynchronously with the trip coil channel switch; One end of the first indicator light (106) is electrically connected to the input end of the first switch channel, one end of the second indicator light (107) is electrically connected to the input end of the second switch channel, the output ends of the first switch channel and the second switch channel are both electrically connected to the negative pole of the start-stop control circuit of the fault removal module, and the other end of the first indicator light (106) and the other end of the second indicator light (107) are both electrically connected to the positive pole of the start-stop control circuit of the fault removal module.

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