An upper isolation upper ground locking loop and switch cabinet

Abstract

The application provides an upper isolation upper grounding locking loop and a switch cabinet, wherein the locking loop comprises a power supply device, a live locking device, a live display with a node, an isolation on-position switch, an isolation off-position switch and a grounding on-position switch, the live display with a node, the grounding on-position switch and the live locking device are connected in series, the isolation on-position switch is connected in parallel with the live display with a node, the isolation off-position switch is connected in parallel with the grounding on-position switch, and the locking loop is formed, the live locking device and the live display with a node and the power supply device are electrically connected, and the live locking device is arranged at a closing tripping device of a circuit breaker mechanism. Whether the line is live is judged by the live display with a node, the state position of the grounding isolation switch is judged by a position signal of a grounding isolation mechanism, and the misoperation of the whole scheme is realized by an electrical and mechanical principle, which is automatic and reliable and meets the five-prevention requirements.

Description

Technical Field

[0001] The present invention relates to the technical field of ring network cabinets, in particular to an upper isolation and upper grounding locking circuit and a switch cabinet. Background Art

[0002] Since the State Grid launched the "12 kV Ring Main Unit (Box) Standardized Design and Customization Plan (2019 Edition)" on September 25, 2019, provincial grid companies within the State Grid region have increased bidding for 12 kV solid-insulated ring main units (boxes) and 12 kV environmentally friendly gas-insulated ring main units (boxes), and have introduced them into the market for widespread application; Figure 1 and Figure 2 However, the plan stipulates that the above two types of ring network cabinets (boxes) are upper isolation, upper grounding and lower circuit breakers (load switches) schemes, which are different from the lower isolation, lower grounding and upper circuit breakers (load switches) schemes used by conventional power supply bureaus. The operating procedures are different, which makes local bureaus very uncomfortable with their use. In addition, this plan is initially promoted. During the application process, it was found that the plan failed to meet the requirements of the five protections and there were safety hazards. Moreover, in the projects supplied, it was detected as unqualified by the operation and inspection department and power supply was prohibited, which caused the power supply of a large number of projects to be delayed, resulting in inevitable losses.

[0003] Five protections usually refers to the abbreviation of five anti-error functions that high-voltage electrical equipment should have to ensure personal safety. It is one of the important measures for power safety. The five protections are to prevent the circuit breaker from being opened or closed by mistake; to prevent the disconnector from being opened or closed under load; to prevent the grounding wire (grounding switch) from being hung (closed) under power; to prevent power from being supplied with the ground wire; and to prevent entering the energized interval by mistake. However, when the existing product with the upper isolation, upper grounding and lower circuit breaker (load switch) solution is applied to the incoming line unit, after the product maintenance or installation before power supply is completed, the circuit breaker is opened, and the grounding switch is not opened according to the normal operating process. Instead, the superior is notified to supply power directly. At this time, the cable room is already energized, and the circuit breaker can continue to operate without electrical and mechanical locking; if the circuit breaker is closed at this time (see Figure 3 ), will cause live grounding, forming a ground fault and tripping the upper circuit breaker. This creates a loophole in the five protections and seriously violates the five protections requirements of GB / T 3906. The grounding switch cannot be closed with power on.

[0004] Therefore, there is an urgent need for an upper isolation and upper grounding locking circuit that can not only meet the standards of the State Grid but also realize the five protection functions. Summary of the Invention

[0005] In order to solve the above problems, the present invention provides an upper isolation and upper grounding locking circuit and switch cabinet, which can not only meet the standards of the State Grid, but also realize the five protection functions and improve the safety of the upper isolation and upper grounding circuit.

[0006] In order to achieve the above-mentioned objectives, the present invention provides an upper isolation and upper grounding locking circuit, comprising a power supply device, an electrified locking device, an electrified indicator with a node, an isolation closing switch, an isolation opening switch and a grounding closing switch, wherein the electrified indicator with a node, the grounding closing switch and the electrified locking device are connected in series in sequence, the isolation closing switch and the electrified indicator with a node are connected in parallel, the isolation opening switch and the grounding closing switch are connected in parallel to form a locking circuit, the electrified locking device and the electrified indicator with a node are electrically connected to the power supply device respectively, and the electrified locking device is arranged at the closing and tripping device of the circuit breaker mechanism.

[0007] As a further improvement to the above method, the upper isolation and upper grounding locking loop further includes a power circuit breaker for controlling the power supply of the entire locking loop.

[0008] As a further improvement of the above method, the isolating and closing switch is a normally open switch.

[0009] As a further improvement of the above method, the isolating split switch is a normally closed switch.

[0010] As a further improvement of the above method, the grounding switch is a normally open switch.

[0011] As a further improvement of the above method, the electrified locking device is a locking electromagnet, which is attracted when the power is on and reset when the power is off.

[0012] As a further improvement to the above method, the charged display with nodes has a built-in node disconnected when the display is charged; and has a built-in node closed when the display is not charged.

[0013] As a further improvement to the above method, when the locking electromagnet is energized, the magnet is attracted, the closing trip device works normally, and the circuit breaker mechanism can be closed normally; when the locking electromagnet is de-energized, the magnet is reset, the closing trip device is restricted, and the circuit breaker mechanism cannot be closed.

[0014] The present invention also provides a switch cabinet, comprising a cabinet body and the upper isolation and upper grounding locking circuit arranged in the cabinet body.

[0015] Since the present invention adopts the above technical solution, the beneficial effects of this application are:

[0016] 1. The upper isolation and upper grounding locking circuit of the present invention comprises a live indicator with a node, a grounding closing switch and a live locking device connected in series in sequence. The isolation closing switch is connected in parallel with the live indicator with a node, and the isolation opening switch is connected in parallel with the grounding closing switch to form a locking circuit. The live locking device and the live indicator with a node are electrically connected to the power supply device, and the live locking device is arranged at the closing and tripping device of the circuit breaker mechanism. The present invention obtains the isolation opening position signal from the grounding closing switch, and then obtains the incoming line live signal from the live indicator with a node. The live indicator with a node draws power from the power supply device and is then connected to the live locking device, forming a locking circuit in series. The live indicator with a node is used to determine whether the line is live, and the position of the grounding isolation switch is determined by the position signal of the grounding isolation mechanism. The entire scheme is prevented from malfunctioning by electrical and mechanical principles, and is automatic, reliable, and not affected by human factors. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention, and those skilled in the art can derive other drawings based on these drawings without inventive effort.

[0018] Figure 1 This is a schematic diagram of a conventional primary system with upper circuit breaker, lower isolation and lower grounding;

[0019] Figure 2 This is a primary system diagram of a standard top-isolated, top-grounded, bottom-circuit breaker required by the State Grid.

[0020] Figure 3 It is a schematic diagram of the reset state of the live locking device of the circuit breaker mechanism of the present invention;

[0021] Figure 4 It is a schematic diagram of the circuit breaker mechanism of the present invention in the state of the live locking device being attracted;

[0022] Figure 5 This is a schematic diagram of the secondary circuit principle of the upper isolation and upper grounding locking loop of the present invention;

[0023] Figure 6 for Figure 5 Component wiring diagram;

[0024] Figure 7 A schematic diagram showing the principle comparison of the primary system and secondary circuit of the upper isolation and upper grounding locking circuit of the present invention when the incoming line is energized and the circuit breaker is grounded;

[0025] Figure 8A schematic diagram showing the principle comparison of the primary system and secondary circuit of the upper isolation and upper grounding locking circuit of the present invention when the incoming line is energized and the circuit breaker is grounded;

[0026] Figure 9 A schematic diagram showing the principle comparison of the primary system and secondary circuit of the upper isolation and upper grounding locking circuit of the present invention when the incoming line is energized and the circuit breaker is isolated and closed;

[0027] Figure 10 A schematic diagram showing the principle comparison of the primary system and secondary circuit of the upper isolation and upper grounding locking circuit of the present invention when the incoming line is de-energized and the circuit breaker is grounded;

[0028] Figure 11 A schematic diagram showing the principle comparison of the primary system and secondary circuit of the upper isolation and upper grounding locking circuit of the present invention when the incoming line is de-energized and the circuit breaker is grounded;

[0029] Figure 12 When the incoming line is without power and the circuit breaker is isolated and closed, the primary system and secondary circuit principle comparison diagram of the upper isolation and upper grounding locking circuit of the present invention are as follows:

[0030] Reference numerals:

[0031] 1. Earthing switch; 2. Disconnector; 3. Magnet; 4. Closing trip device; 5. Circuit breaker mechanism. DETAILED DESCRIPTION

[0032] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0033] It should be noted that all directional indications in the embodiments of the present invention, such as first, second, up, down, left, right, front, back, etc., are only used to explain the relative position relationship, movement status, etc. between the various components in a certain specific posture as shown in the accompanying drawings. If the specific posture changes, the directional indication will also change accordingly.

[0034] In addition, the technical solutions between the various embodiments of the present invention can be combined with each other, but it must be based on the fact that ordinary technicians in this field can implement it. When the combination of technical solutions is mutually contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0035] The present invention will be further described below with reference to the accompanying drawings:

[0036] Example 1:

[0037] Reference, Figure 3-Figure 6 The present invention provides an upper isolation and upper grounding locking circuit, comprising a power supply device, an electrified locking device DSN, an electrified indicator DXN with a node, an isolation closing switch S10, an isolation opening switch S11 and a grounding closing switch S12. The electrified indicator DXN with a node, the grounding closing switch S12 and the electrified locking device DSN are connected in series in sequence. The isolation closing switch S10 and the electrified indicator DXN with a node are connected in parallel. The isolation opening switch S11 and the grounding closing switch S12 are connected in parallel to form a locking circuit. The electrified locking device DSN and the electrified indicator DXN with a node are electrically connected to the power supply device respectively. The electrified locking device DSN is arranged at the closing and tripping device of the circuit breaker mechanism 5. The present invention obtains an isolation open position signal from the grounding closing switch S12, obtains an incoming line live signal from a live indicator DXN with a node, draws power from a power supply device, and is then connected to a live locking device DSN, forming a whole series lock loop. The live indicator DXN with a node is used to determine whether the line is energized, and the position signal of the grounding isolation mechanism 5 is used to determine the state of the grounding isolation switch. The entire solution is implemented to prevent misoperation through electrical and mechanical principles. The solution is automatic, reliable, and not affected by human factors, and can meet the five protection requirements of GB / T 3906.

[0038] In this embodiment, referring to Figure 6 The isolating closing switch S10 is a normally open switch, and the isolating opening switch S11 is a normally closed switch; the grounding closing switch S12 is a normally open switch; the energized locking device DSN is a locking electromagnet, which is attracted when powered and reset when powered off; the energized display DXN with a node has a built-in node disconnected when energized; and a built-in node closed when de-energized.

[0039] As a preferred embodiment, when the locking electromagnet is energized, the magnet 3 is attracted, the closing trip device 4 works normally, and the circuit breaker mechanism 5 can be closed normally; when the locking electromagnet is de-energized, the magnet 3 is reset, the closing trip device 4 is restricted and cannot rotate or move, and the circuit breaker mechanism 5 cannot be closed.

[0040] In this embodiment, the upper isolation and upper grounding locking loop further includes a power circuit breaker QF1 for controlling the power supply of the entire locking loop, and the power circuit breaker QF1 is connected in series to the locking loop.

[0041] After closing the power circuit breaker QF1, the locking circuit is connected to the power supply and starts working. This locking circuit has 6 working states, in which five protection operations are realized. The details are as follows:

[0042] The first is when the incoming line is energized, that is, when the energized display DXN shows energized, the grounding switch 1 is in the closed position, and the isolating switch 2 is in the open position. Figure 7 , the built-in node of the live display DXN is disconnected, the isolation closing switch S10 is disconnected, the isolation opening switch S11 is closed, and the grounding closing switch S12 is closed; the entire electrical circuit is disconnected, the locking electromagnet DSN is in a power-free state, the magnet 3 is in a reset state, the closing trip device 4 is restricted, and the circuit breaker mechanism 5 cannot be closed, meeting the five-protection function;

[0043] The second type is when the incoming line is energized, that is, when the energized display DXN shows energized, the grounding switch 1 is in the open position, and the isolating switch 2 is in the open position. Figure 8 , the built-in node of the live display DXN is disconnected, the isolation closing switch S10 is disconnected, the isolation opening switch S11 is disconnected, and the grounding closing switch S12 is disconnected; the entire electrical circuit is disconnected, the locking electromagnet DSN is in a power-free state, the magnet 3 is in a reset state, the closing trip device 4 is restricted, and the circuit breaker mechanism 5 cannot be closed, meeting the five protection functions;

[0044] The third type is when the incoming line is energized, that is, when the energized display DXN shows energized, the grounding switch 1 is in the open position, and the isolating switch 2 is in the closed position. Figure 9 , the built-in node of the live display DXN is disconnected, the isolation closing switch S10 is closed, the isolation opening switch S11 is closed, and the grounding closing switch S12 is disconnected; the entire electrical circuit is connected, the locking electromagnet DSN is energized, the magnet 3 is attracted, the closing trip device 4 is not restricted, and the circuit breaker mechanism 5 can close normally, meeting the five-protection function;

[0045] The fourth type is when the incoming line is not energized, that is, when the energized display DXN shows no power, the grounding switch 1 is in the closed position, and the isolating switch 2 is in the open position. Figure 10 , the built-in node of the live display DXN is closed, the isolation closing switch S10 is disconnected, the isolation opening switch S11 is closed, and the grounding closing switch S12 is closed; the entire electrical circuit is connected, the locking electromagnet DSN is energized, the magnet 3 is attracted, the closing trip device 4 is not restricted, and the circuit breaker mechanism 5 can close normally, meeting the five-protection function;

[0046] The fifth type is when the incoming line is not energized, that is, when the energized display DXN shows no power, the grounding switch 1 is in the open position, and the isolating switch 2 is in the open position. Figure 11 , the built-in node of the live display DXN is closed, the isolation closing switch S10 is disconnected, the isolation opening switch S11 is disconnected, and the grounding closing switch S12 is disconnected; the entire electrical circuit is disconnected, the locking electromagnet DSN is in a power-free state, the magnet 3 is in a reset state, the closing trip device 4 is restricted, and the circuit breaker mechanism 5 cannot be closed, meeting the five protection functions;

[0047] The sixth type is when the incoming line is not energized, that is, when the energized display DXN shows no power, the grounding switch 1 is in the open position, and the isolating switch 2 is in the closed position. Figure 12 , the built-in node of the live display DXN is closed, the isolation closing switch S10 is closed, the isolation opening switch S11 is closed, and the grounding closing switch S12 is disconnected; the entire electrical circuit is connected, the electromagnet DSN is energized, the magnet 3 is attracted, the closing trip device 4 is not restricted, and the circuit breaker mechanism 5 can close normally, meeting the five protection functions;

[0048] The locking circuit of the upper-isolated, upper-grounded, lower circuit breaker of the present invention satisfies the five-protection functions in all six working states of the upper-isolated, upper-grounded, lower circuit breaker solution, and automatically realizes the locking or unlocking state through the inherent position state and the power display state of the switch, thereby avoiding possible human error operation.

[0049] Example 2:

[0050] The present invention also provides a switch cabinet, comprising a cabinet body and the upper isolation and upper grounding locking circuit arranged in the cabinet body.

[0051] The above is a detailed introduction to the present invention. Specific examples are used herein to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only intended to help understand the method and core concept of the present invention. It should be noted that those skilled in the art may make various improvements and modifications to the present invention without departing from the principles of the present invention, and such improvements and modifications also fall within the scope of protection of the claims of the present invention.

Claims

1. An upper isolation and upper grounding locking circuit, characterized in that: It includes a power supply device, a live locking device, a live indicator with a node, an isolating closing switch, an isolating opening switch and a grounding closing switch. The live indicator with a node, the grounding closing switch and the live locking device are connected in series in sequence. The isolating closing switch and the live indicator with a node are connected in parallel. The isolating opening switch and the grounding closing switch are connected in parallel to form a locking circuit. The live locking device and the live indicator with a node are electrically connected to the power supply device respectively; the live locking device is a locking electromagnet, which is attracted when powered and reset when powered off; when the live indicator with a node is powered, the built-in node is disconnected; when it is not powered, the built-in node is closed; the upper isolating and upper grounding locking circuit also includes a power circuit breaker for controlling the power supply of the entire locking circuit. The power circuit breaker is connected in series on the locking circuit, and the number of the power circuit breakers is 2.

2. The upper isolation and upper grounding locking circuit according to claim 1, characterized in that: The live locking device is arranged at the closing and tripping device of the circuit breaker mechanism.

3. The upper isolation and upper grounding locking circuit according to any one of claims 1-2, characterized in that: The isolating closing switch is a normally open switch.

4. The upper isolation and upper grounding locking circuit according to any one of claims 1-2, characterized in that: The isolating split switch is a normally closed switch.

5. The upper isolation and upper grounding locking circuit according to any one of claims 1-2, characterized in that: The grounding switch is a normally open switch.

6. The upper isolation and upper grounding locking circuit according to any one of claims 1-2, characterized in that: When the locking electromagnet is energized, the magnet is attracted, the closing trip device works normally, and the circuit breaker mechanism can close normally; when the locking electromagnet is de-energized, the magnet is reset, the closing trip device is restricted, and the circuit breaker mechanism cannot close.

7. A switch cabinet, characterized in that: The utility model comprises a cabinet body and an upper isolation and upper grounding locking circuit as claimed in claims 1 to 6 arranged in the cabinet body.

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