CN113466632B - Uninterrupted DC grounding searching system and uninterrupted DC grounding searching method - Google Patents
Uninterrupted DC grounding searching system and uninterrupted DC grounding searching method Download PDFInfo
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- CN113466632B CN113466632B CN202110870971.1A CN202110870971A CN113466632B CN 113466632 B CN113466632 B CN 113466632B CN 202110870971 A CN202110870971 A CN 202110870971A CN 113466632 B CN113466632 B CN 113466632B
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- 238000004891 communication Methods 0.000 description 1
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Classifications
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
- G01R31/08—Locating faults in cables, transmission lines, or networks
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Abstract
The invention discloses a system and a method for searching uninterrupted direct current grounding, which comprise a direct current bus positive electrode, a direct current bus negative electrode, a double-power undisturbed switching device I-path power positive electrode, a double-power undisturbed switching device I-path power negative electrode, a double-power undisturbed switching device II-path power positive electrode, a double-power undisturbed switching device II-path power negative electrode, a standby direct current power system, a double-power undisturbed switching device, other load branch circuit breakers, load branch circuit breakers to be detected, a double-power switching device output positive electrode, a double-power switching device output negative electrode, other load branches and load branches to be detected.
Description
Technical Field
The invention belongs to the technical field of power plant electrical equipment, and relates to a system and a method for searching direct current grounding without power failure.
Background
The direct current system is widely applied to thermal power plants, hydroelectric power plants, various substations and other places using direct current equipment, and provides power equipment of the direct current power supply for protection, automatic devices, communication, accident lighting, emergency power supply and breaker opening and closing operations. The direct current system is an independent power supply, is not influenced by a generator, station service electricity and a system operation mode, and ensures important equipment for providing the direct current power supply under the condition of external alternating current interruption. Therefore, the importance thereof is self-evident.
The insulation reduction or the grounding fault of the positive electrode or the negative electrode of the direct current system is a common fault of the direct current system, which can cause the voltage deviation of the positive electrode or the negative electrode of the direct current system to the ground, possibly cause incorrect actions of equipment such as protection, safety automatic devices and the like, and the defect needs to be removed in time. The effective method adopted is 'pull Lu Fa', but 'pull Lu Fa' has the serious defect of power failure of a load branch, and if the characteristics of the load are unclear, the actual operation is often dangerous, and the important load branch can be powered off, so that the safe operation of the system is endangered.
Disclosure of Invention
The invention aims to overcome the defects of the prior art, and provides a system and a method for searching uninterrupted direct current grounding.
In order to achieve the above purpose, the uninterrupted DC grounding search system comprises a DC bus positive electrode, a DC bus negative electrode, a double-power undisturbed switching device I-path power positive electrode, a double-power undisturbed switching device I-path power negative electrode, a double-power undisturbed switching device II-path power positive electrode, a double-power undisturbed switching device II-path power negative electrode, a standby DC power system, a double-power undisturbed switching device, other load branch circuit breakers, load branch circuit breakers to be tested, a double-power switching device output positive electrode, a double-power switching device output negative electrode, other load branches and load branches to be tested;
the direct current bus positive electrode and the direct current bus negative electrode are connected with other load branches through other load branch circuit breakers, and the direct current bus positive electrode 1 and the direct current bus negative electrode are connected with the load branches to be tested through the load branch circuit breakers to be tested;
the double-power undisturbed switching device comprises a double-power switching device I-path switching switch and a double-power switching device II-path switching switch, wherein a positive electrode of the double-power undisturbed switching device I-path power and a negative electrode of the double-power undisturbed switching device I-path power are connected with one side of the double-power switching device I-path switching switch, a positive electrode of the double-power undisturbed switching device II-path power and a negative electrode of the double-power switching device II-path power are connected with one side of the double-power switching device II-path switching switch, a positive electrode and a negative electrode of the other side of the double-power switching device I-path switching switch are respectively connected with an output positive electrode of the double-power switching device and an output negative electrode of the double-power switching device, and a positive electrode and a negative electrode of the other side of the double-power switching device II-path switching switch are respectively connected with an output positive electrode of the double-power switching device and an output negative electrode of the double-power switching device;
the direct current bus positive electrode is connected with a circuit between the load branch circuit breaker to be tested and the positive electrode of the I-path power supply of the dual-power undisturbed switching device;
the circuit between the negative electrode of the direct current bus and the circuit breaker of the load branch circuit to be tested is connected with the negative electrode of the I-path power supply of the dual-power undisturbed switching device;
the circuit between the load branch circuit breaker to be tested and the load branch circuit to be tested is connected with the circuit between the output positive electrode of the dual-power switching device and the output negative electrode of the dual-power switching device;
the standby direct current power supply system is connected with the positive electrode of the II-path power supply of the double-power undisturbed switching device and the negative electrode of the II-path power supply of the double-power undisturbed switching device.
The circuit between the positive electrode of the direct current bus and the circuit between the circuit breaker of the load branch circuit to be tested and the positive electrode of the I-path power supply of the dual-power undisturbed switching device, the circuit between the negative electrode of the direct current bus and the circuit between the circuit breaker of the load branch circuit to be tested and the negative electrode of the I-path power supply of the dual-power undisturbed switching device, the circuit between the circuit breaker of the load branch circuit to be tested and the circuit between the output positive electrode of the dual-power supply switching device and the output negative electrode of the dual-power supply switching device, the standby direct current power supply system and the positive electrode of the II-path power supply of the dual-power undisturbed switching device and the negative electrode of the II-path power supply of the dual-power undisturbed switching device are all connected through wires and wire clamps.
The uninterrupted DC grounding searching method comprises the following steps:
1) Setting the dual-power undisturbed switching device to be in a I-path closing and II-path opening mode;
2) Connecting an I-path power supply of the dual-power undisturbed switching device with the input end of a load branch circuit breaker to be tested;
3) Connecting a II-path power supply of the dual-power undisturbed switching device with a standby direct-current power supply system;
4) Connecting the output end of the dual-power undisturbed switching device with the output end of the load branch circuit breaker to be tested;
5) Switching off a power circuit breaker of a load branch circuit to be tested, wherein the load branch circuit to be tested is powered by a I-path of a dual-power undisturbed switching device;
6) Setting a dual-power undisturbed switching device as a I-path open mode and a II-path closed mode, switching a load branch to be detected to a II-path instantaneously, and supplying power by a standby direct-current power supply system;
7) Judging whether the grounding fault phenomenon of the direct current system disappears, if so, turning to the step 8), otherwise, detecting the next load branch to be detected, and turning to the step 2);
8) The current load branch to be tested has a ground fault.
The invention has the following beneficial effects:
when the uninterrupted direct current grounding searching system and method disclosed by the invention are specifically operated, the double-power undisturbed switching device is used for instantaneously (less than 5 ms) transferring the load of the load branch circuit to be detected to the standby direct current section, the uninterrupted operation of the load branch circuit in a pull way is realized during the period of searching the grounding fault of the direct current system, the safety of firepower, hydraulic power plants, various substations and other systems using direct current equipment is ensured, the online fault detection of direct current equipment with voltage levels of 220V, 110V and the like is realized, the cost is lower, the design conception is ingenious, the principle is simple, the field personnel can easily master the system, and the application range is wide.
Drawings
FIG. 1 is a schematic diagram of the structure of the present invention;
fig. 2 is a flow chart of the present invention.
The direct current bus positive electrode 1 is a direct current bus negative electrode 2 is a direct current bus negative electrode 3 is a double-power undisturbed switching device I-path power negative electrode, 4 is a double-power undisturbed switching device I-path power negative electrode, 5 is a double-power undisturbed switching device II-path power positive electrode, 6 is a double-power undisturbed switching device II-path power negative electrode, 7 is a wire clamp, 8 is a wire, 9 is a standby direct current power system, 10 is a double-power undisturbed switching device, 11 is a double-power switching device I-path switching switch, 12 is a double-power switching device II-path switching switch, 13 is another load branch circuit breaker, 14 is a load branch circuit breaker to be tested, 15 is a double-power switching device output positive electrode, 16 is a double-power switching device output negative electrode, 17 is another load branch circuit, and 18 is a load branch to be tested.
Detailed Description
In order to make the present invention better understood by those skilled in the art, the following description will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings, and it is apparent that the described embodiments are only some embodiments of the present invention, not all embodiments, but not intended to limit the scope of the present disclosure. In addition, in the following description, descriptions of well-known structures and techniques are omitted so as not to unnecessarily obscure the concepts of the present disclosure. All other embodiments, which can be made by those skilled in the art based on the embodiments of the present invention without making any inventive effort, shall fall within the scope of the present invention.
In the accompanying drawings, there is shown a schematic structural diagram in accordance with a disclosed embodiment of the invention. The figures are not drawn to scale, wherein certain details are exaggerated for clarity of presentation and may have been omitted. The shapes of the various regions, layers and their relative sizes, positional relationships shown in the drawings are merely exemplary, may in practice deviate due to manufacturing tolerances or technical limitations, and one skilled in the art may additionally design regions/layers having different shapes, sizes, relative positions as actually required.
Referring to fig. 1, the uninterrupted dc ground finding system of the present invention includes a dc bus positive electrode 1, a dc bus negative electrode 2, a dual-power undisturbed switching device I-path power positive electrode 3, a dual-power undisturbed switching device I-path power negative electrode 4, a dual-power undisturbed switching device II-path power positive electrode 5, a dual-power undisturbed switching device II-path power negative electrode 6, a wire clip 7, a wire 8, a standby dc power system 9, a dual-power undisturbed switching device 10, a other load branch circuit breaker 13, a load branch circuit breaker 14 to be tested, a dual-power switching device output positive electrode 15, a dual-power switching device output negative electrode 16, a other load branch circuit 17 and a load branch circuit 18 to be tested;
the direct current bus positive electrode 1 and the direct current bus negative electrode 2 are connected with other load branches 17 through other load branch circuit breakers 13, and the direct current bus positive electrode 1 and the direct current bus negative electrode 2 are connected with load branches 18 to be tested through load branch circuit breakers 14 to be tested;
the dual-power undisturbed switching device 10 comprises a dual-power switching device I-path switching switch 11 and a dual-power switching device II-path switching switch 12, wherein a dual-power undisturbed switching device I-path power positive electrode 3 and a dual-power undisturbed switching device I-path power negative electrode 4 are connected with one side of the dual-power switching device I-path switching switch 11, a dual-power undisturbed switching device II-path power positive electrode 5 and a dual-power undisturbed switching device II-path power negative electrode 6 are connected with one side of the dual-power switching device II-path switching switch 12, the positive electrode and the negative electrode of the other side of the dual-power switching device I-path switching switch 11 are respectively connected with a dual-power switching device output positive electrode 15 and a dual-power switching device output negative electrode 16, and the positive electrode and the negative electrode of the other side of the dual-power switching device II-path switching switch 12 are respectively connected with the dual-power switching device output positive electrode 15 and the dual-power switching device output negative electrode 16.
The line between the direct current bus positive electrode 1 and the load branch circuit breaker 14 to be tested and the positive electrode 3 of the I-path power supply of the dual-power undisturbed switching device, the line between the direct current bus negative electrode 2 and the load branch circuit breaker 14 to be tested and the negative electrode 4 of the I-path power supply of the dual-power undisturbed switching device, the line between the load branch circuit breaker 14 to be tested and the load branch circuit 18 to be tested and the line between the output positive electrode 15 of the dual-power switching device and the output negative electrode 16 of the dual-power switching device, the standby direct current power supply system 9 and the positive electrode 5 of the II-path power supply of the dual-power undisturbed switching device and the negative electrode 6 of the II-path power supply of the dual-power undisturbed switching device are all connected through the lead 8 and the wire clamp 7.
Referring to fig. 2, the uninterrupted direct current grounding searching method of the invention comprises the following steps:
1) Setting the dual power undisturbed switching device 10 to be in an I-path closed and II-path open mode;
2) Connecting the I-path power supply of the dual-power undisturbed switching device 10 with the input end of the load branch circuit breaker 14 to be tested;
3) Connecting a II-path power supply of the dual-power undisturbed switching device 10 with a standby direct-current power supply system 9;
4) Connecting the output end of the dual-power undisturbed switching device 10 with the output end of the load branch circuit breaker 14 to be tested;
5) The power circuit breaker 14 of the load branch circuit to be tested is disconnected, and the load branch circuit 18 to be tested is powered by the I path of the dual-power undisturbed switching device 10;
6) The double-power undisturbed switching device 10 is set to be in an I-path open and II-path closed mode, and a load branch 18 to be detected is instantaneously switched to be in an II-path state and is powered by the standby direct-current power supply system 9;
7) Judging whether the grounding fault phenomenon of the direct current system disappears, and when the grounding fault phenomenon of the direct current system disappears, turning to the step 8), otherwise, detecting the next load branch 18 to be detected, and turning to the step 2);
8) There is a ground fault in the load branch 18 currently under test.
The dual-power undisturbed switching device 10 is various devices for realizing undisturbed dual-power switching functions, such as ASCO, ATS, fast switching, and the like.
The backup dc power supply system 9 includes a dc bus, a battery, and a rectifying device.
Claims (6)
1. The uninterrupted direct current grounding searching system is characterized by comprising a direct current bus positive electrode (1), a direct current bus negative electrode (2), a double-power undisturbed switching device I-path power positive electrode (3), a double-power undisturbed switching device I-path power negative electrode (4), a double-power undisturbed switching device II-path power positive electrode (5), a double-power undisturbed switching device II-path power negative electrode (6), a standby direct current power system (9), a double-power undisturbed switching device (10), other load branch circuit breakers (13), load branch circuit breakers (14) to be tested, a double-power switching device output positive electrode (15), a double-power switching device output negative electrode (16), other load branches (17) and load branches (18) to be tested;
the direct current bus positive electrode (1) and the direct current bus negative electrode (2) are connected with other load branches (17) through other load branch circuit breakers (13), and the direct current bus positive electrode (1) and the direct current bus negative electrode (2) are connected with a load branch circuit (18) to be tested through a load branch circuit breaker (14) to be tested;
the double-power undisturbed switching device (10) comprises a double-power switching device I-path switching switch (11) and a double-power switching device II-path switching switch (12), wherein a double-power undisturbed switching device I-path power positive electrode (3) and a double-power undisturbed switching device I-path power negative electrode (4) are connected with one side of the double-power switching device I-path switching switch (11), a double-power undisturbed switching device II-path power positive electrode (5) and a double-power undisturbed switching device II-path power negative electrode (6) are connected with one side of the double-power switching device II-path switching switch (12), the positive electrode and the negative electrode of the other side of the double-power switching device I-path switching switch (11) are respectively connected with a double-power switching device output positive electrode (15) and a double-power switching device output negative electrode (16), and the positive electrode and the negative electrode of the other side of the double-power switching device II-path switching switch (12) are respectively connected with the double-power switching device output positive electrode (15) and the double-power switching device output negative electrode (16);
the direct current bus positive electrode (1) is connected with a circuit between the load branch circuit breaker (14) to be tested and the I-path power positive electrode (3) of the dual-power undisturbed switching device;
the direct current bus cathode (2) is connected with a circuit between the load branch circuit breaker (14) to be tested and the I-path power supply cathode (4) of the dual-power undisturbed switching device;
the circuit between the load branch circuit breaker (14) to be tested and the load branch circuit (18) to be tested is connected with the circuit between the output positive electrode (15) of the dual-power switching device and the output negative electrode (16) of the dual-power switching device;
the standby direct current power supply system (9) is connected with the positive electrode (5) of the II-path power supply of the double-power-supply undisturbed switching device and the negative electrode (6) of the II-path power supply of the double-power-supply undisturbed switching device.
2. The uninterruptible direct current grounding search system according to claim 1, wherein a line between a direct current bus positive electrode (1) and a load branch circuit breaker (14) to be detected and a double-power undisturbed switching device I-path power positive electrode (3), a line between a direct current bus negative electrode (2) and the load branch circuit breaker (14) to be detected and a double-power undisturbed switching device I-path power negative electrode (4), a line between the load branch circuit breaker (14) to be detected and a load branch circuit (18) to be detected and a line between a double-power switching device output positive electrode (15) and a double-power switching device output negative electrode (16), and a standby direct current power system (9) and a double-power undisturbed switching device II-path power positive electrode (5) and a double-power undisturbed switching device II-path power negative electrode (6) are all connected through a wire (8) and a wire clamp (7).
3. The uninterruptible direct current ground finding system of claim 1 wherein the dual power undisturbed switching device (10) is an ATS.
4. The uninterruptible direct current ground finding system of claim 1 wherein the dual power undisturbed switching device (10) is ASCO.
5. The uninterruptible direct current ground finding system of claim 1 wherein the backup direct current power supply system (9) comprises a direct current bus, a battery and a rectifying device.
6. The uninterrupted direct current grounding searching method is characterized by comprising the following steps based on the uninterrupted direct current grounding searching system as claimed in claim 1:
1) Setting a dual-power undisturbed switching device (10) to be in an I-path closed mode and a II-path open mode;
2) Connecting an I-path power supply of the dual-power undisturbed switching device (10) with the input end of a load branch circuit breaker (14) to be tested;
3) Connecting a II-path power supply of the dual-power undisturbed switching device (10) with a standby direct-current power supply system (9);
4) The output end of the dual-power undisturbed switching device (10) is connected with the output end of a load branch circuit breaker (14) to be tested;
5) Disconnecting the power circuit breaker (14) of the load branch circuit to be tested, and supplying power to the load branch circuit (18) to be tested through the I-path of the dual-power undisturbed switching device (10);
6) The double-power undisturbed switching device (10) is set to be in a first-path open mode and a second-path closed mode, a load branch (18) to be detected is instantaneously switched to the second-path, and a standby direct-current power supply system (9) supplies power;
7) Judging whether the grounding fault phenomenon of the direct current system disappears, if so, turning to the step 8), otherwise, detecting the next load branch (18) to be detected, and turning to the step 2);
8) The current load branch (18) to be tested has a ground fault.
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| CN202110870971.1A CN113466632B (en) | 2021-07-30 | 2021-07-30 | Uninterrupted DC grounding searching system and uninterrupted DC grounding searching method |
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| CN202110870971.1A CN113466632B (en) | 2021-07-30 | 2021-07-30 | Uninterrupted DC grounding searching system and uninterrupted DC grounding searching method |
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| CN113466632A CN113466632A (en) | 2021-10-01 |
| CN113466632B true CN113466632B (en) | 2023-12-19 |
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