CN112572241A - Existing electrified railway cable commissioning construction method - Google Patents
Existing electrified railway cable commissioning construction method Download PDFInfo
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- CN112572241A CN112572241A CN202011525213.8A CN202011525213A CN112572241A CN 112572241 A CN112572241 A CN 112572241A CN 202011525213 A CN202011525213 A CN 202011525213A CN 112572241 A CN112572241 A CN 112572241A
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60M—POWER SUPPLY LINES, AND DEVICES ALONG RAILS, FOR ELECTRICALLY- PROPELLED VEHICLES
- B60M1/00—Power supply lines for contact with collector on vehicle
- B60M1/12—Trolley lines; Accessories therefor
- B60M1/28—Manufacturing or repairing trolley lines
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60M—POWER SUPPLY LINES, AND DEVICES ALONG RAILS, FOR ELECTRICALLY- PROPELLED VEHICLES
- B60M3/00—Feeding power to supply lines in contact with collector on vehicles; Arrangements for consuming regenerative power
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Abstract
The invention belongs to the technical field of electrified railway cable construction, and provides a construction method for commissioning an existing electrified railway cable, which comprises the following steps: step S1, blocking the line in the range of the whole power supply arm related to the cable operation; step S2, performing three impact tests: carrying out impact test preparation before each impact test; during impact test, one end of a cable to be shipped is connected with a contact net positioned at one end of a tunnel, the other end of the cable is disconnected with the contact net, then a grounding wire is removed, a No. 214 feeder line is powered on, power is continuously supplied for 5min, and the cable is observed to have abnormal phenomena of no abnormal sound, no abnormal odor and no color change; step S3, performing a no-load test: on the basis of the third impact test, the state of the cable to be put into operation is kept unchanged, namely the no-load state is kept for 24 hours; step S4, carrying out a loading test: and (3) respectively connecting the two ends of the cable to be put into operation with contact nets at the two ends of the tunnel, and loading the circuit for 24 hours. The invention improves the construction quality and the construction efficiency.
Description
Technical Field
The invention belongs to the technical field of electrified railway cable construction, and particularly relates to a construction method for commissioning an existing electrified railway cable.
Background
Along with the continuous development of railway construction in China, the reconstruction construction of the existing electrified railway is gradually increased, and because the railway tunnel constructed in the early stage is low in clearance, the overhead construction of a contact net of 'simple suspension + current-carrying cable' is often adopted to pass through a low-clearance tunnel in the energy expansion reconstruction construction of the existing electrified railway, namely, a 27.5kV current-carrying cable is laid on the wall of the tunnel in an overhead mode to replace a catenary, so that the effect of increasing the current-carrying area is achieved. In the existing electrified railway energy expansion transformation construction, how to rapidly, efficiently and safely put the cable into a traction power supply system on the basis of ensuring that the railway operation is not influenced is a difficult problem at present.
Disclosure of Invention
The invention provides a cable commissioning construction method for an existing electrified railway, aiming at solving the problems of low cable commissioning efficiency and high safety risk in the existing electrified railway energy expansion transformation construction.
In order to solve the technical problems, the invention adopts the technical scheme that: a construction method for commissioning the existing electrified railway cable comprises the following steps:
step S1, blocking the line in the range of the whole power supply arm related to the cable operation;
step S2, performing three impact tests: carrying out test preparation before each impact test; during an impact test, one end of a cable to be shipped is connected with a contact net positioned at one end of a tunnel, the other end of the cable is disconnected with the contact net, then a grounding wire is removed, a No. 214 feeder line is powered on, power is continuously supplied for 5min, the cable is observed to have abnormal phenomena of no abnormal sound, no abnormal odor and no color change, if not, the impact test preparation is carried out again, and the next impact test is carried out; one end of the cable to be put into operation is disconnected with a contact net during the second impact test, the other end of the cable to be put into operation is connected with the contact net at the other end of the tunnel, and the connection mode of the cable to be put into operation during the third impact test is the same as that of the first impact test;
step S3, performing a no-load test: on the basis of the third impact test, the state of the cable to be put into operation is kept unchanged, namely the no-load state is kept for 24 hours, a specially-assigned person is arranged to regularly patrol during the period, the cable is observed to have abnormal phenomena of no noise, peculiar smell and color change, and the no-load test of the cable is finished after 24 hours;
step S4, carrying out a loading test: and (3) respectively connecting two ends of the cable to be shipped with contact nets at two ends of the tunnel, carrying out circuit loading, wherein the loading lasts for 24 hours, a specially-assigned person is arranged to regularly patrol and measure the temperature in the period, and the cable loading test is finished if no abnormity exists after 24 hours.
The specific method for test preparation is as follows: the power supply arm of the whole power supply arm related to the operation of the cable is powered off, then the contact net is tested, and after the contact net is confirmed to be uncharged, the ground wire is hung on the contact net.
In step S2, the method specifically includes the following steps:
s201, after preparing an impact test, performing a first impact test: connecting one end of a cable to be shipped with a contact net, disconnecting the other end of the cable from the contact net, removing a grounding wire, transmitting power to a No. 214 feeder line, continuously transmitting power for 5min, and observing whether the cable has abnormal phenomena such as no abnormal sound, peculiar smell and color change; if not, entering the next step;
s202, preparing an impact test again, and entering a second impact test: connecting the other end of the cable to be shipped with a contact net, disconnecting one end of the cable from the contact net, removing a grounding wire, transmitting power to a No. 214 feeder line, continuously transmitting power for 5min, and observing whether the cable has abnormal phenomena such as no abnormal sound, peculiar smell and color change; if not, entering the next step;
s202, preparing an impact test again, and entering a third impact test: and connecting one end of the cable to be shipped with a contact net, disconnecting the other end of the cable from the contact net, removing the grounding wire, transmitting power to the No. 214 feeder line, continuously transmitting power for 5min, observing whether the cable has abnormal phenomena such as no abnormal sound, peculiar smell and color change, and if not, finishing the impact test.
In step S3 and step S4, the frequency of the timing round is 4 h.
The number of the cables to be put into operation is two.
One ends of two cables to be put into operation are connected with a contact net positioned at one end of the tunnel through an isolating switch K1 and an isolating switch K3 respectively, and the other ends of the two cables to be put into operation are connected with the contact net positioned at the other end of the tunnel through an isolating switch K5 and an isolating switch K7 respectively; in the steps S2-S4, the connection and disconnection of the cable to be put into operation and the contact net are realized through the isolating switch K1, the isolating switch K3, the isolating switch K5 and the isolating switch K7.
In step S4, before the circuit load test, a test preparation step is further included.
Compared with the prior art, the invention has the following beneficial effects:
1. the invention provides a method for commissioning construction of an existing electrified railway cable, which is suitable for commissioning construction of the existing electrified railway cable, and is simple, efficient and high in safety.
2. The invention carries out cable commissioning construction by taking the power supply arm as a unit, and can complete commissioning of all cables in the range of one power supply arm at one time.
3. The invention can be completed under the condition of not influencing railway operation, only needs to carry out skylight operation twice, and has short occupied time.
4. The invention can also carry out commissioning construction on cables in the range of a plurality of power supply arms at the same time, and can realize one-time commissioning completion of the cables in the large range.
In a word, the existing electrified railway cable commissioning construction method solves the problems of long commissioning time, low efficiency and poor safety of the traditional existing electrified railway cable; and the modes of impact test and loading test are adopted, so that the construction quality and the construction efficiency are improved, and good economic benefit and social benefit are obtained.
Drawings
Fig. 1 is a schematic view of the commissioning of a number 1 tunnel cable according to an embodiment of the present invention;
FIG. 2 is a flow chart of an impact test in an embodiment of the present invention;
FIG. 3 is a flowchart of a loading test in an embodiment of the present invention.
Detailed Description
In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below, and it is obvious that the described embodiments are some embodiments of the present invention, but not all embodiments; all other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
As shown in fig. 1 to 3, an embodiment of the invention provides a commissioning construction method for cables of an existing electrified railway, wherein one ends of two cables to be commissioned are connected with a contact network at one end of a tunnel through an isolating switch K1 and an isolating switch K3 respectively, and the other ends of the two cables to be commissioned are connected with the contact network at the other end of the tunnel through an isolating switch K5 and an isolating switch K7 respectively. The two ends of the tunnel are respectively a station 1 and a station 2, and two lines of a contact network are respectively connected with a 214 feeder line and a 213 feeder line of a substation in the direction of the station 1. The commissioning construction method mainly comprises the following seven steps.
Step one, line blocking.
The railway line dispatching department is contacted in advance, the lines in the range of the whole power supply arm related to the cable commissioning are blocked, as shown in fig. 1, when two cables of the No. 1 tunnel are commissioned, all the lines related to the No. 214 feeder line need to be blocked, and a locomotive is not allowed to pass through.
And step two, the power supply arm is powered off and contacts the net hanging ground wire.
Contacting a railway power dispatching department, cutting off the power of the No. 214 feeder line power supply arm, carrying out electricity testing operation on the contact network by using a railway contact network electricity testing pen, and confirming that the contact network is uncharged. Grounding personnel need to ground the catenary and the contact wire of the contact net through a grounding wire outside the construction range of No. 1 tunnel, firstly, residual current is led to the ground, the human body is prevented from being injured by the residual current, and secondly, railway safety accidents caused by misdelivery of electricity are prevented.
And step three, carrying out a first impact test.
Operating the isolating switch K1 and the isolating switch K3 to be in a closed state; the disconnecting switch K5 and the disconnecting switch K7 are operated to be in an open state. The station 1 direction side of two cables is ensured to be connected with a contact network, and the station 2 direction side is disconnected with the contact network. And (3) removing the grounding wire, connecting the power dispatching pair to the No. 214 feeder line, continuously transmitting power for 5min, observing whether the cable has abnormal phenomena of no noise, peculiar smell and color change, if all the abnormal phenomena are normal, connecting the power dispatching pair to the No. 214 feeder line, and stopping the first impact test.
And step four, carrying out a second impact test.
And repeating the second step, and carrying out electricity testing and grounding on the contact network. Operating the K1 isolating switch and the K3 isolating switch to be in an open state; the disconnecting switch K5 and the disconnecting switch K7 are operated to be in a closed state. The disconnection of the station 1 direction side of the two cables and the contact network is ensured, and the station 2 direction side is connected with the contact network. And (3) removing the grounding wire, connecting the power dispatching pair to transmit power to the No. 214 feeder, continuously transmitting the power for 5min, observing whether the cable has abnormal phenomena of no noise, peculiar smell and color change, if all the phenomena are normal, connecting the power dispatching pair to power off the No. 214 feeder, and finishing the second impact test.
And step five, carrying out a third impact test.
And repeating the second step, and carrying out electricity testing and grounding on the contact network. Operating the isolating switch K1 and the isolating switch K3 to be in a closed state; the disconnecting switch K5 and the disconnecting switch K7 are operated to be in an open state. The station 1 direction side of two cables is ensured to be connected with a contact network, and the station 2 direction side is disconnected with the contact network. And (3) removing the grounding wire, connecting the power dispatching pair to the No. 214 feeder line, continuously transmitting power for 5min, observing whether the cable has abnormal phenomena of no noise, peculiar smell and color change, if all the abnormal phenomena are normal, connecting the power dispatching pair to the No. 214 feeder line, and ending the third impact test.
And step six, carrying out no-load test.
And on the basis of the fifth step, keeping the isolating switch K1 and the isolating switch K3 in a closed state, and keeping the isolating switch K5 and the isolating switch K7 in an open state, namely in an idle state. The no-load state is kept for 24 hours, a specially-assigned person is arranged to perform patrol inspection once every 4 hours in the period, the abnormal phenomena of no noise, peculiar smell and color change of the cable are observed, and the no-load test of the cable is finished if no abnormality exists after 24 hours.
The flow chart of the impact test of steps one to six is shown in fig. 2.
And step seven, carrying out a loading test.
As shown in fig. 3, after the cable no-load test is passed, the cable loading test is performed by using the 2 nd blocking point, the line is blocked, after the power failure of the contact network, the test preparation needs to be performed again, namely, the step of the step two is performed again, after the electricity is tested and the ground is hung on the contact network, the switch is closed again, and only the isolating switch K5 and the isolating switch K7 need to be closed again (at this time, the isolating switch K1 and the isolating switch K3 are kept closed), and the line is opened after the power is transmitted after the point is finished. The cable loading needs to be continued for 24 hours, a specially-assigned person is arranged to patrol and measure the temperature once every 4 hours, and the cable loading test is finished if no abnormity occurs after 24 hours. And finishing the operation of the No. 1 tunnel and 2 cables.
In conclusion, the invention provides a construction method for commissioning the cable of the existing electrified railway, which solves the problems of long commissioning time, low efficiency and poor safety of the cable of the traditional existing electrified railway; and the modes of impact test and loading test are adopted, so that the construction quality and the construction efficiency are improved, and good economic benefit and social benefit are obtained.
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; and the modifications or the substitutions do not make the essence of the corresponding technical solutions depart from the scope of the technical solutions of the embodiments of the present invention.
Claims (7)
1. The construction method for the existing electrified railway cable commissioning is characterized by comprising the following steps:
step S1, blocking the line in the range of the whole power supply arm related to the cable operation;
step S2, performing three impact tests: carrying out test preparation before each impact test; during an impact test, one end of a cable to be shipped is connected with a contact net positioned at one end of a tunnel, the other end of the cable is disconnected with the contact net, then a grounding wire is removed, a No. 214 feeder line is powered on, power is continuously supplied for 5min, the cable is observed to have abnormal phenomena of no abnormal sound, no abnormal odor and no color change, if not, the impact test preparation is carried out again, and the next impact test is carried out; one end of the cable to be put into operation is disconnected with a contact net during the second impact test, the other end of the cable to be put into operation is connected with the contact net at the other end of the tunnel, and the connection mode of the cable to be put into operation during the third impact test is the same as that of the first impact test;
step S3, performing a no-load test: on the basis of the third impact test, the state of the cable to be put into operation is kept unchanged, namely the no-load state is kept for 24 hours, a specially-assigned person is arranged to regularly patrol during the period, the cable is observed to have abnormal phenomena of no noise, peculiar smell and color change, and the no-load test of the cable is finished after 24 hours;
step S4, carrying out a loading test: and (3) respectively connecting two ends of the cable to be shipped with contact nets at two ends of the tunnel, carrying out circuit loading, wherein the loading lasts for 24 hours, a specially-assigned person is arranged to regularly patrol and measure the temperature in the period, and the cable loading test is finished if no abnormity exists after 24 hours.
2. The existing electrified railway cable commissioning construction method of claim 1, wherein the specific method for test preparation is as follows: the power supply arm of the whole power supply arm related to the operation of the cable is powered off, then the contact net is tested, and after the contact net is confirmed to be uncharged, the ground wire is hung on the contact net.
3. The existing electrified railway cable commissioning construction method of claim 1, wherein the step S2 specifically comprises the following steps:
s201, after preparing an impact test, performing a first impact test: connecting one end of a cable to be shipped with a contact net, disconnecting the other end of the cable from the contact net, removing a grounding wire, transmitting power to a No. 214 feeder line, continuously transmitting power for 5min, and observing whether the cable has abnormal phenomena such as no abnormal sound, peculiar smell and color change; if not, entering the next step;
s202, preparing an impact test again, and entering a second impact test: connecting the other end of the cable to be shipped with a contact net, disconnecting one end of the cable from the contact net, removing a grounding wire, transmitting power to a No. 214 feeder line, continuously transmitting power for 5min, and observing whether the cable has abnormal phenomena such as no abnormal sound, peculiar smell and color change; if not, entering the next step;
s202, preparing an impact test again, and entering a third impact test: and connecting one end of the cable to be shipped with a contact net, disconnecting the other end of the cable from the contact net, removing the grounding wire, transmitting power to the No. 214 feeder line, continuously transmitting power for 5min, observing whether the cable has abnormal phenomena such as no abnormal sound, peculiar smell and color change, and if not, finishing the impact test.
4. The method for commissioning of an existing electrified railway cable according to claim 1, wherein the frequency of the timing rounds in steps S3 and S4 is 4 h.
5. The method for commissioning construction of an existing electrified railway cable according to claim 1, wherein the number of the cables to be commissioned is two.
6. The existing electrified railway cable commissioning construction method as recited in claim 5, wherein one end of each of two cables to be commissioned is connected to a contact network at one end of the tunnel through a disconnecting switch K1 and a disconnecting switch K3, respectively, and the other end of each of the two cables to be commissioned is connected to the contact network at the other end of the tunnel through a disconnecting switch K5 and a disconnecting switch K7, respectively; in the steps S2-S4, the connection and disconnection of the cable to be put into operation and the contact net are realized through the isolating switch K1, the isolating switch K3, the isolating switch K5 and the isolating switch K7.
7. The method of claim 1, wherein the step of preparing the test is further included before the step of performing the circuit loading test in the step S4.
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114475370A (en) * | 2022-03-14 | 2022-05-13 | 西南交通大学 | Short circuit sectional protection method for contact network of cable through power supply system |
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| CN114475370B (en) * | 2022-03-14 | 2023-04-07 | 西南交通大学 | Short circuit sectional protection method for contact network of cable through power supply system |
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| CN112572241B (en) | 2022-04-01 |
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