CN114243887A - Bus-tie spare power automatic switching method for urban rail transit intelligent transformer substation - Google Patents
Bus-tie spare power automatic switching method for urban rail transit intelligent transformer substation Download PDFInfo
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- CN114243887A CN114243887A CN202111594944.2A CN202111594944A CN114243887A CN 114243887 A CN114243887 A CN 114243887A CN 202111594944 A CN202111594944 A CN 202111594944A CN 114243887 A CN114243887 A CN 114243887A
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- automatic switching
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- 230000009471 action Effects 0.000 claims abstract description 22
- 238000004891 communication Methods 0.000 claims abstract description 15
- 230000003137 locomotive effect Effects 0.000 abstract description 5
- 230000009286 beneficial effect Effects 0.000 abstract description 2
- 230000003993 interaction Effects 0.000 description 3
- 238000005516 engineering process Methods 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J9/00—Circuit arrangements for emergency or stand-by power supply, e.g. for emergency lighting
- H02J9/04—Circuit arrangements for emergency or stand-by power supply, e.g. for emergency lighting in which the distribution system is disconnected from the normal source and connected to a standby source
- H02J9/06—Circuit arrangements for emergency or stand-by power supply, e.g. for emergency lighting in which the distribution system is disconnected from the normal source and connected to a standby source with automatic change-over, e.g. UPS systems
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
- H02H7/00—Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions
- H02H7/26—Sectionalised protection of cable or line systems, e.g. for disconnecting a section on which a short-circuit, earth fault, or arc discharge has occured
- H02H7/261—Sectionalised protection of cable or line systems, e.g. for disconnecting a section on which a short-circuit, earth fault, or arc discharge has occured involving signal transmission between at least two stations
- H02H7/262—Sectionalised protection of cable or line systems, e.g. for disconnecting a section on which a short-circuit, earth fault, or arc discharge has occured involving signal transmission between at least two stations involving transmissions of switching or blocking orders
Abstract
The invention provides a bus tie spare power automatic switching method for an intelligent substation of urban rail transit, wherein a medium-voltage power supply system of the urban rail transit comprises a plurality of substations, each substation comprises two sections of buses, a spare power automatic switching device and a protection device, the spare power automatic switching devices in the substations are in communication connection with the protection devices, the spare power automatic switching devices in the substations are in communication connection with primary equipment in a line, and the spare power automatic switching devices of the substations are in communication connection. The invention has the beneficial effects that: when the voltage-loss fault occurs to the bus of the transformer substation, the spare power automatic switching device of the transformer substation performs spare power automatic switching action, and therefore stable operation of the locomotive is guaranteed.
Description
Technical Field
The invention belongs to the field of urban rail transit, and particularly relates to a bus tie spare power automatic switching method for an intelligent substation of urban rail transit.
Background
In an urban rail transit medium-voltage power supply system, a bus I and a bus II of a transformer substation respectively provide electric energy for feed-out lines connected with each other. When one section of the bus or the corresponding inlet wire of the bus breaks down, the bus is subjected to voltage loss, and a subordinate power supply system is influenced, even the operation of the locomotive is influenced. In order to avoid the problem, the breaker between the two buses is closed, and the power supply of the voltage-losing bus is restored, so that the stable operation of the system is ensured. In the present medium voltage power supply system, the protection set up mainly includes: differential protection and current backup protection at two ends of the looped network. Due to the popularization of the intelligent substation technology, the IEC61850 communication technology is relied on, and the two types of protection are upgraded from a traditional point-to-point mode to a comprehensive discrimination mode relying on network topology. After the trouble takes place, the fault line of excision that can be accurate quick sends the signal to the device of female union department simultaneously, realizes that the female union is equipped with the automatic switching action, resumes the power supply.
Disclosure of Invention
In view of this, the invention aims to provide a bus tie spare power automatic switching method for an intelligent substation of urban rail transit, so as to realize bus tie spare power automatic switching action when a voltage loss fault occurs on a bus of the substation, and further ensure stable operation of a locomotive.
In order to achieve the purpose, the technical scheme of the invention is realized as follows:
the invention provides a bus tie spare power automatic switching system of an intelligent substation for urban rail transit, which comprises a plurality of substations, wherein each substation comprises two sections of buses, a spare power automatic switching device and a protection device, the spare power automatic switching devices in the substations are in communication connection with the protection devices, the spare power automatic switching devices in the substations are in communication connection with primary equipment in a line, and the spare power automatic switching devices of the substations are in communication connection.
The invention also provides a method for bus tie spare power automatic switching of the urban rail transit intelligent substation based on the bus tie spare power automatic switching system of the urban rail transit intelligent substation, which comprises the following steps:
s1, when the medium-voltage power supply system of the urban rail transit breaks down and the buses of part of the transformer substations are not pressurized, judging whether the spare power automatic switching device can receive a spare power automatic switching starting signal of the protection device or not;
if the backup power automatic switching device can receive a backup power automatic switching starting signal of the protection device, the backup power automatic switching device carries out backup power automatic switching action;
if the backup power automatic switching starting signal of the protection device cannot be received, the step S3 is carried out;
s2, the spare power automatic switching device of the transformer substation judges whether to carry out spare power automatic switching operation or not by detecting the bus voltage condition of the spare power automatic switching device and combining the bus voltage condition of the adjacent transformer substations, and the judgment mode is as follows:
if the two sections of bus voltage conditions detected by the spare power automatic switching device of the transformer substation are that one section has pressure and the other section has no pressure, the bus voltage information of the adjacent transformer substation is that both the two sections have pressure, and the bus voltage information of the other adjacent transformer substation is that one section has pressure and the other section has no pressure, the step S4 is entered;
otherwise, go to step S4;
s3, making corresponding backup power switching actions according to the fault positions detected by the backup power automatic switching devices of the transformer substation;
and S4, completing the spare power automatic switching action by a method of matching the voltage-loss spare power automatic switching with the time level difference.
Further, before step S1 is executed, the backup power automatic switching device needs to be charged, and the backup power automatic switching device charging method includes:
s01, preparing for charging;
s02, charging the spare power automatic switching device according to the bus voltage condition, the switching condition of the incoming line short-circuit device and the switching condition of the bus-coupled circuit breaker;
if the two sections of buses of the substation where the spare power automatic switching device is located have pressure, the two sections of buses enter the line short-circuit device to be in the closed position, and the bus tie breaker is in the separated position, the step S03 is carried out;
otherwise, the charging fails;
and S03, finishing charging.
Further, the determination conditions for selecting the backup power automatic switching operation in step S3 are as follows:
if the incoming line of a non-voltage section bus of the transformer substation has a fault and the positions of incoming and outgoing line breakers of adjacent transformer substations with two sections of buses having voltage are separated, the spare power automatic switching device trips off the incoming line breaker of the transformer substation and closes the bus coupler breaker of the transformer substation to complete the spare power automatic switching action;
if the non-pressure section bus of the transformer substation breaks down and the positions of the inlet and outlet line breakers of the adjacent transformer substations with two sections of buses having pressure are all in a closed position, the spare power automatic switching device of the transformer substation sends a spare power automatic switching starting signal to the adjacent transformer substation with one section of non-pressure, and after the spare power automatic switching starting signal is received, the spare power automatic switching device of the adjacent transformer substation with one section of non-pressure trips the inlet line breaker of the pressure-losing bus, closes the bus coupler breaker and completes the spare power automatic switching action.
Compared with the prior art, the method for bus tie spare power automatic switching of the intelligent substation of the urban rail transit has the following beneficial effects:
(1) according to the method for bus-tie spare power automatic switching of the intelligent substation of the urban rail transit, the spare power automatic switching device is installed on the substation of the existing urban rail transit medium-voltage power supply system, the spare power automatic switching device is matched with the original protection device for use, and when a voltage-loss fault occurs on a bus of the substation, the spare power automatic switching device of the substation can perform spare power automatic switching action, so that stable operation of a locomotive is guaranteed.
(2) According to the method for bus-tie spare power automatic switching of the urban rail transit intelligent substation, the spare power automatic switching devices of all power distribution stations are networked, the information of the spare power automatic switching devices of adjacent power distribution stations can be collected, the information of the spare power automatic switching devices is judged, and the spare power automatic switching action is carried out, so that the condition that the spare power automatic switching function fails after the communication network of the existing protection device fails is avoided.
Drawings
The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate an embodiment of the invention and, together with the description, serve to explain the invention and not to limit the invention. In the drawings:
fig. 1 is a schematic view of a topology structure of a medium voltage network power supply system according to an embodiment of the present invention;
fig. 2 is a schematic view of a connection structure of the backup automatic switching device between the transformer substations according to the embodiment of the present invention;
fig. 3 is a schematic view of a connection structure of the backup power automatic switching device according to the embodiment of the invention;
fig. 4 is a schematic flow chart of a bus tie backup automatic switching method of an intelligent substation according to an embodiment of the present invention.
Detailed Description
It should be noted that the embodiments and features of the embodiments may be combined with each other without conflict.
The present invention will be described in detail below with reference to the embodiments with reference to the attached drawings.
The first embodiment is as follows:
as shown in fig. 1 to fig. 3, the embodiment provides a bus tie spare power automatic switching system of an intelligent substation for urban rail transit, which includes a plurality of substations, the substation includes two sections of buses, spare power automatic switching devices and protection devices, the spare power automatic switching devices in the substation are in communication connection with the protection devices to realize information interaction, the spare power automatic switching devices in the substation are in communication connection with primary equipment in a line to realize remote signaling and control information interaction, and the spare power automatic switching devices of each substation are in communication connection to realize information interaction. The spare power automatic switching device is installed on a transformer substation of a medium-voltage power supply system of the existing urban rail transit, the spare power automatic switching device is matched with an original protection device for use, and when a voltage-loss fault occurs on a bus of the transformer substation, the spare power automatic switching device of the transformer substation can perform spare power automatic switching action, so that stable operation of a locomotive is guaranteed.
Example two:
as shown in fig. 4, the embodiment provides a method for bus tie backup automatic switching of an intelligent substation of urban rail transit based on the bus tie backup automatic switching system of the intelligent substation of urban rail transit in the first embodiment, which includes the following steps:
s01, preparing for charging;
s02, charging the spare power automatic switching device according to the bus voltage condition, the switching condition of the incoming line short-circuit device and the switching condition of the bus-coupled circuit breaker;
if the two sections of buses of the substation where the spare power automatic switching device is located have pressure, the two sections of buses enter the line short-circuit device to be in the closed position, and the bus tie breaker is in the separated position, the step S03 is carried out;
otherwise, the charging fails;
s03, completing charging;
s1, when the medium-voltage power supply system of the urban rail transit breaks down and the buses of part of the transformer substations are not pressurized, judging whether the spare power automatic switching device can receive a spare power automatic switching starting signal of the protection device or not;
if the backup power automatic switching device can receive a backup power automatic switching starting signal of the protection device, the backup power automatic switching device carries out backup power automatic switching action;
if the backup power automatic switching starting signal of the protection device cannot be received, the step S2 is carried out;
s2, the spare power automatic switching device of the transformer substation judges whether to carry out spare power automatic switching operation or not by detecting the bus voltage condition of the spare power automatic switching device and combining the bus voltage condition of the adjacent transformer substations, and the judgment mode is as follows:
in fig. 1, if the two-segment bus voltage condition of the substation 2 detected by the backup automatic switching device of the substation 2 is that one segment has voltage and one segment has no voltage, and the bus voltage information of the adjacent substation 1 has both voltage and the bus voltage information of the other adjacent substation 3 has one segment has voltage and one segment has no voltage, the process proceeds to step S3;
otherwise, go to step S4;
s3, making corresponding backup power switching actions according to the fault positions detected by the backup power automatic switching devices of the transformer substation;
if the incoming line of the non-voltage section bus I of the transformer substation 2 has a fault and the incoming and outgoing line breaker positions of the adjacent transformer substations 1 with two sections of buses having voltage have a position division, the spare power automatic switching device 1 trips off the incoming line breaker 201 of the transformer substation 2 and closes the bus tie breaker 200 of the transformer substation 2 to complete the spare power automatic switching action;
if the non-voltage section bus I of the transformer substation 2 breaks down, and the positions of the inlet and outlet circuit breakers of the adjacent transformer substations 1 with two sections of buses having voltage are all closed, the spare power automatic switching device 2 of the transformer substation 2 sends a spare power automatic switching starting signal to the adjacent transformer substation 3 with one section of non-voltage, after the spare power automatic switching starting signal is received, the spare power automatic switching device 3 of the adjacent transformer substation 3 with one section of non-voltage trips off the inlet circuit breaker 301 of the non-voltage bus I, the bus tie circuit breaker 300 is closed, and the spare power automatic switching action is completed.
And S4, completing the spare power automatic switching action by a method of matching the voltage-loss spare power automatic switching with the time level difference.
The spare power automatic switching devices of all power distribution stations are networked, the information of the spare power automatic switching devices of adjacent power distribution stations can be collected, the information of the spare power automatic switching devices is judged, and the spare power automatic switching action is carried out, so that the condition that the spare power automatic switching function fails after the communication network of the existing protection device breaks down is avoided.
Those of ordinary skill in the art will appreciate that the elements and method steps of the examples described in connection with the embodiments disclosed herein may be embodied in electronic hardware, computer software, or combinations of both, and that the components and steps of the examples have been described in a functional general in the foregoing description for the purpose of clearly illustrating the interchangeability of hardware and software. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the implementation. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present invention.
In the several embodiments provided in the present application, it should be understood that the disclosed method and system may be implemented in other ways. For example, the above described division of elements is merely a logical division, and other divisions may be realized, for example, multiple elements or components may be combined or integrated into another system, or some features may be omitted, or not executed. The units may or may not be physically separate, and components displayed as units may or may not be physical units, that is, may be located in one place, or may be distributed on a plurality of network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of the embodiment of the present invention.
Finally, it should be noted that: the above embodiments are only used to illustrate the technical solution of the present invention, and not to limit the same; while the invention has been described in detail and with reference to the foregoing embodiments, it will be understood by those skilled in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some or all of the technical features may be equivalently replaced; such modifications and substitutions do not depart from the spirit and scope of the present invention, and they should be construed as being included in the following claims and description.
The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents, improvements and the like that fall within the spirit and principle of the present invention are intended to be included therein.
Claims (4)
1. The utility model provides an urban rail transit intelligent substation bus tie spare power automatic switching system which characterized in that: the automatic switching device comprises a plurality of transformer substations, wherein each transformer substation comprises two sections of buses, a spare automatic switching device and a protection device, the spare automatic switching device in each transformer substation is in communication connection with the protection device, the spare automatic switching device in each transformer substation is in communication connection with primary equipment in a circuit, and the spare automatic switching devices of the transformer substations are in communication connection.
2. The method for bus tie spare power automatic switching of the urban rail transit intelligent substation based on the bus tie spare power automatic switching system of the urban rail transit intelligent substation of claim 1 is characterized by comprising the following steps: the method comprises the following steps:
s1, when the medium-voltage power supply system of the urban rail transit breaks down and the buses of part of the transformer substations are not pressurized, judging whether the spare power automatic switching device can receive a spare power automatic switching starting signal of the protection device or not;
if the backup power automatic switching device can receive a backup power automatic switching starting signal of the protection device, the backup power automatic switching device carries out backup power automatic switching action;
if the backup power automatic switching starting signal of the protection device cannot be received, the step S3 is carried out;
s2, the spare power automatic switching device of the transformer substation judges whether to carry out spare power automatic switching operation or not by detecting the bus voltage condition of the spare power automatic switching device and combining the bus voltage condition of the adjacent transformer substations, and the judgment mode is as follows:
if the two sections of bus voltage conditions detected by the spare power automatic switching device of the transformer substation are that one section has pressure and the other section has no pressure, the bus voltage information of the adjacent transformer substation is that both the two sections have pressure, and the bus voltage information of the other adjacent transformer substation is that one section has pressure and the other section has no pressure, the step S4 is entered;
otherwise, go to step S4;
s3, making corresponding backup power switching actions according to the fault positions detected by the backup power automatic switching devices of the transformer substation;
and S4, completing the spare power automatic switching action by a method of matching the voltage-loss spare power automatic switching with the time level difference.
3. The method for bus tie spare power automatic switching of the urban rail transit intelligent substation according to claim 2 is characterized in that: before step S1 is executed, the backup power automatic switching device needs to be charged, and the backup power automatic switching device charging method is as follows:
s01, preparing for charging;
s02, charging the spare power automatic switching device according to the bus voltage condition, the switching condition of the incoming line short-circuit device and the switching condition of the bus-coupled circuit breaker;
if the two sections of buses of the substation where the spare power automatic switching device is located have pressure, the two sections of buses enter the line short-circuit device to be in the closed position, and the bus tie breaker is in the separated position, the step S03 is carried out;
otherwise, the charging fails;
and S03, finishing charging.
4. The method for bus tie spare power automatic switching of the urban rail transit intelligent substation according to claim 2 is characterized in that: the conditions for determining the backup power automatic switching operation in step S3 are as follows:
if the incoming line of a non-voltage section bus of the transformer substation has a fault and the positions of incoming and outgoing line breakers of adjacent transformer substations with two sections of buses having voltage are separated, the spare power automatic switching device trips off the incoming line breaker of the transformer substation and closes the bus coupler breaker of the transformer substation to complete the spare power automatic switching action;
if the non-pressure section bus of the transformer substation breaks down and the positions of the inlet and outlet line breakers of the adjacent transformer substations with two sections of buses having pressure are all in a closed position, the spare power automatic switching device of the transformer substation sends a spare power automatic switching starting signal to the adjacent transformer substation with one section of non-pressure, and after the spare power automatic switching starting signal is received, the spare power automatic switching device of the adjacent transformer substation with one section of non-pressure trips the inlet line breaker of the pressure-losing bus, closes the bus coupler breaker and completes the spare power automatic switching action.
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| CN202111594944.2A CN114243887B (en) | 2021-12-23 | 2021-12-23 | Method for bus-tie spare power automatic switching of intelligent substation for urban rail transit |
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| CN202111594944.2A CN114243887B (en) | 2021-12-23 | 2021-12-23 | Method for bus-tie spare power automatic switching of intelligent substation for urban rail transit |
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Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN203632361U (en) * | 2013-12-27 | 2014-06-04 | 国家电网公司 | Logic controlling device for 110kV line automatic bus transfer equipment |
| CN109245101A (en) * | 2018-11-13 | 2019-01-18 | 国网四川省电力公司天府新区供电公司 | The method for promoting statements based on collusion substation's power supply reliability |
| CN109818410A (en) * | 2017-11-21 | 2019-05-28 | 南京南瑞继保电气有限公司 | A kind of rapidly self-healing method of urban track traffic ac power supply system |
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- 2021-12-23 CN CN202111594944.2A patent/CN114243887B/en active Active
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN203632361U (en) * | 2013-12-27 | 2014-06-04 | 国家电网公司 | Logic controlling device for 110kV line automatic bus transfer equipment |
| CN109818410A (en) * | 2017-11-21 | 2019-05-28 | 南京南瑞继保电气有限公司 | A kind of rapidly self-healing method of urban track traffic ac power supply system |
| CN109245101A (en) * | 2018-11-13 | 2019-01-18 | 国网四川省电力公司天府新区供电公司 | The method for promoting statements based on collusion substation's power supply reliability |
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