CN114942358B - Multi-electric-quantity synchronous test method for subway power supply system - Google Patents
Multi-electric-quantity synchronous test method for subway power supply system Download PDFInfo
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- CN114942358B CN114942358B CN202210525950.0A CN202210525950A CN114942358B CN 114942358 B CN114942358 B CN 114942358B CN 202210525950 A CN202210525950 A CN 202210525950A CN 114942358 B CN114942358 B CN 114942358B
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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
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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
- G01R31/081—Locating faults in cables, transmission lines, or networks according to type of conductors
- G01R31/086—Locating faults in cables, transmission lines, or networks according to type of conductors in power transmission or distribution networks, i.e. with interconnected conductors
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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
- G01R31/40—Testing power supplies
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Abstract
The invention discloses a multi-electric-quantity synchronous test method for a subway power supply system, which specifically comprises the following steps: acquiring current measurement loop drawings and voltage measurement loop drawings of an anode cabinet, an inversion incoming line cabinet and a steel rail potential limiting device in a traction substation; determining the potential of the steel rail, the outgoing line current of the positive cabinet and the incoming line current of the inversion incoming line cabinet according to a voltage measurement loop drawing and a current measurement loop drawing, wherein the incoming line current of the inversion incoming line cabinet corresponds to a secondary test terminal; and (3) feeding the electric cable into the corresponding test terminal which is connected in parallel, synchronously collecting the potential of the steel rail and the outgoing current of the positive cabinet, and inverting the incoming current of the incoming cabinet. The synchronous test method is safe and reliable, and the test data can be used for evaluating the potential level of the actual subway steel rail so as to guide the development of operation and maintenance work and ensure the safe and stable operation of the subway.
Description
Technical Field
The invention belongs to the field of rail transit operation safety, and particularly relates to a multi-electric-quantity synchronous test method for a subway power supply system.
Background
The urban rail transit power supply system in China generally adopts direct current power supply, and alternating current voltage is converted into 1500V through a rectifier unit. The rectifier unit is connected to the contact net through the positive pole cabinet to provide power for the train. Typically, a rail, or track, is used as a return rail, and electrical energy is passed through the train and returns current to the rectifier unit cathode via the track. In practical engineering, the steel rail has a longitudinal resistance, and the steel rail cannot be completely insulated from the ground, so that potential is generated between the steel rail and the ground, namely the potential of the steel rail. Too high rail potential will crisis subway passengers safety. Assessing rail potential levels is critical to guiding their protection.
In order to evaluate the potential level of the steel rail in an actual line, synchronous tests need to be carried out on multiple electric quantities such as the potential of the steel rail. Directly measuring the current of the feeder line which is drawn once, and threatening the personal safety of the testers. And the method of adding the Hall sensor can influence the normal operation of the equipment.
Disclosure of Invention
The invention aims to realize synchronous test of a plurality of electric quantities by measuring the current and the voltage of a secondary transmitter of a rail potential limiting device, a positive electrode cabinet and an inversion incoming line cabinet. The test data are used for evaluating the potential level of the steel rail in the actual subway line, and further guiding the operation and maintenance of the subway line. Therefore, the invention provides a multi-electric-quantity synchronous test method for a subway power supply system.
The invention discloses a multi-electric-quantity synchronous test method for a subway power supply system, which comprises the following steps of:
step A: and acquiring current measurement loop drawings and voltage measurement loop drawings of the positive cabinet, the inversion incoming cabinet and the steel rail potential limiting device in the traction substation.
And (B) step (B): and determining the potential of the steel rail, the outgoing line current of the positive cabinet and the incoming line current of the inversion incoming line cabinet according to the voltage measurement loop drawing and the current measurement loop drawing, wherein the incoming line current of the inversion incoming line cabinet corresponds to the secondary test terminal.
Step B1: and obtaining a corresponding test terminal of the positive cabinet according to the drawing and the terminal inquiry in the secondary cabinet door of the positive cabinet:
and inquiring a current measurement loop drawing of the positive cabinet to obtain the transformation ratio B1/B2 of the outgoing cable of the positive cabinet and serial numbers K1 and K2 of the outgoing ports of the current divider.
And inquiring a current measuring loop drawing of the positive cabinet to obtain transformation ratios I1/I2 of the current transmitters corresponding to K1 and K2 and output port numbers X1 and X2 of the current transmitters.
Opening a secondary cabinet door of the positive pole cabinet, and finding X1 and X2 according to the marks of all cables in the secondary chamber; x1 and X2 are positive cabinet outgoing line current test terminals.
Step B2: according to the drawing and the terminal inquiry in the secondary cabinet door of the inversion incoming cabinet, the corresponding test terminal of the inversion incoming cabinet is obtained:
and inquiring the current measuring loop drawing of the inversion inlet wire cabinet to obtain the transformation ratio B3/B4 of the inlet wire cable shunt of the inversion inlet wire cabinet and serial numbers K3 and K4 of the shunt output ports of the inversion inlet wire cabinet.
And inquiring a current measuring loop drawing of the inversion incoming line cabinet to obtain a transformation ratio I3/I4 of the current transducer corresponding to K3 and K4 and the serial numbers X3 and X4 of the output ports of the current transducer.
Opening a secondary cabinet door of the inversion incoming line cabinet, and finding X3 and X4 according to the marks of all cables in the secondary cabinet; x3 and X4 are the inversion inlet wire cabinet inlet wire current test terminals.
Step B3: obtaining a corresponding test terminal of the steel rail potential limiting device according to the drawing and the query of the terminal in the secondary cabinet door of the steel rail potential limiting device:
inquiring a voltage measurement loop drawing of the steel rail potential limiting device to obtain the shunt transformation ratio B5/B6 of the connecting cable connected with the steel rail in the steel rail potential limiting device and the serial numbers K5 and K6 of the shunt output ports of the shunt.
Inquiring a voltage measurement loop drawing of the steel rail potential limiting device to obtain transformation ratios U1/U2 and xx output port numbers X5 and X6 of voltage transmitters corresponding to K5 and K6.
Opening a secondary cabinet door of the steel rail potential limiting device, and finding X5 and X6 according to the marks of all cables in the secondary cabinet; x5 and X6 are rail potential test terminals of the rail potential limiting device.
Step C: and (3) feeding the electric cable into the corresponding test terminal which is connected in parallel, synchronously collecting the potential of the steel rail and the outgoing current of the positive cabinet, and inverting the incoming current of the incoming cabinet.
Step C1: in order to ensure the safe and reliable wiring process, the measured traction station is powered off during the stop period of the subway train, so that all electrical cabinets in the traction station are in a power-off state.
Step C2: and opening a secondary cabinet door of the positive cabinet, and sequentially connecting the two test cables to X1 and X2.
Step C3: opening the inversion incoming line cabinet secondary cabinet door, and sequentially connecting the two test cables into X3 and X4.
Step C4: and opening a secondary cabinet door of the steel rail potential limiting device, and sequentially connecting two test cables into X5 and X6.
Step C5: the other end of the test cable is connected with a signal synchronous test device.
Step C6: and restoring the power supply of the traction station so that the traction station is in a live running state.
Step C7: in the time T before the train starts to run, the signal synchronous testing device is powered to realize the signal testing of X1, X2, X3, X4, X5 and X6; t is arbitrarily valued within 10 minutes to 60 minutes. The signals obtained by the test are represented by S3, S4 and S5 in sequence.
Step C8: after the test is completed, the tested traction station is powered off, so that all electrical cabinets in the traction station are in a power-off state.
Step C9: and removing cables connected to the secondary cabinet door of the positive cabinet, the secondary cabinet door of the inversion incoming line cabinet and the secondary cabinet door of the steel rail potential limiting device, and powering off the signal synchronization testing device.
Step C10: after the test is completed, test data analysis is carried out, and output voltage and current of the rectifier unit are calculated; inverting the direct current of the energy feeder; rail potential.
Calculating the output current of the rectifier unit:
and D, calculating direct current side current of the inversion energy feed device:
and (3) calculating the potential of the steel rail:
the beneficial technical effects of the invention are as follows:
according to the invention, the synchronous test of the steel rail potential, the outgoing line current of the rectifier unit and the feeding line current is realized by measuring the current and the voltage of the secondary side transducer of the inversion incoming line cabinet, which is connected with the outgoing line of the rectifier unit in series, and is connected with the incoming line of the inversion feedback device. The testing method only involves the secondary, firstly, personal safety threat to testing operators does not exist, and secondly, normal operation of a primary system is not affected, and safety risks brought to normal operation of subways due to testing are reduced.
Drawings
Fig. 1 is a schematic diagram of a subway electric quantity synchronous test for verifying a rail electric potential simulation model according to the method of the invention.
Fig. 2 is an electrical diagram of a portion of a positive tank current measurement loop.
Detailed Description
The invention will be described in further detail with reference to the accompanying drawings and detailed description.
The invention provides technical support for evaluating the data required by the steel rail potential level in the actual subway line, and the synchronous test of the steel rail potential, the outgoing line current of the rectifier unit and the feeding line current can be realized by utilizing the measuring steel rail potential limiting device, the positive cabinet connected with the outgoing line of the rectifier unit in series and the current and the voltage of the secondary transmitter of the inversion feeding line cabinet connected with the feeding line of the inversion feedback device. A schematic diagram of the subway electric quantity synchronous test for verifying the rail electric potential simulation model is shown in fig. 1.
The invention discloses a multi-electric-quantity synchronous test method for a subway power supply system, which comprises the following steps of:
step A: and acquiring current measurement loop drawings and voltage measurement loop drawings of the positive cabinet, the inversion incoming cabinet and the steel rail potential limiting device in the traction substation.
And (B) step (B): and determining the potential of the steel rail, the outgoing line current of the positive cabinet and the incoming line current of the inversion incoming line cabinet according to the voltage measurement loop drawing and the current measurement loop drawing, wherein the incoming line current of the inversion incoming line cabinet corresponds to the secondary test terminal.
Step B1: obtaining a corresponding test terminal of the positive cabinet (the electrical diagram of the current measurement loop part of the positive cabinet is shown in figure 2) according to the drawing and the terminal inquiry in the secondary cabinet door of the positive cabinet:
and inquiring a current measurement loop drawing of the positive cabinet to obtain the transformation ratio B1/B2 of the outgoing cable of the positive cabinet and serial numbers K1 and K2 of the outgoing ports of the current divider.
And inquiring a current measuring loop drawing of the positive cabinet to obtain transformation ratios I1/I2 of the current transmitters corresponding to K1 and K2 and output port numbers X1 and X2 of the current transmitters.
Opening a secondary cabinet door of the positive pole cabinet, and finding X1 and X2 according to the marks of all cables in the secondary chamber; x1 and X2 are positive cabinet outgoing line current test terminals.
Step B2: according to the drawing and the terminal inquiry in the secondary cabinet door of the inversion incoming cabinet, the corresponding test terminal of the inversion incoming cabinet is obtained:
and inquiring the current measuring loop drawing of the inversion inlet wire cabinet to obtain the transformation ratio B3/B4 of the inlet wire cable shunt of the inversion inlet wire cabinet and serial numbers K3 and K4 of the shunt output ports of the inversion inlet wire cabinet.
And inquiring a current measuring loop drawing of the inversion incoming line cabinet to obtain a transformation ratio I3/I4 of the current transducer corresponding to K3 and K4 and the serial numbers X3 and X4 of the output ports of the current transducer.
Opening a secondary cabinet door of the inversion incoming line cabinet, and finding X3 and X4 according to the marks of all cables in the secondary cabinet; x3 and X4 are the inversion inlet wire cabinet inlet wire current test terminals.
Step B3: obtaining a corresponding test terminal of the steel rail potential limiting device according to the drawing and the query of the terminal in the secondary cabinet door of the steel rail potential limiting device:
inquiring a voltage measurement loop drawing of the steel rail potential limiting device to obtain the shunt transformation ratio B5/B6 of the connecting cable connected with the steel rail in the steel rail potential limiting device and the serial numbers K5 and K6 of the shunt output ports of the shunt.
Inquiring a voltage measurement loop drawing of the steel rail potential limiting device to obtain transformation ratios U1/U2 and xx output port numbers X5 and X6 of voltage transmitters corresponding to K5 and K6.
Opening a secondary cabinet door of the steel rail potential limiting device, and finding X5 and X6 according to the marks of all cables in the secondary cabinet; x5 and X6 are rail potential test terminals of the rail potential limiting device.
Step C: and (3) feeding the electric cable into the corresponding test terminal which is connected in parallel, synchronously collecting the potential of the steel rail and the outgoing current of the positive cabinet, and inverting the incoming current of the incoming cabinet.
Step C1: in order to ensure the safe and reliable wiring process, the measured traction station is powered off during the stop period of the subway train, so that all electrical cabinets in the traction station are in a power-off state.
Step C2: and opening a secondary cabinet door of the positive cabinet, and sequentially connecting the two test cables to X1 and X2.
Step C3: opening the inversion incoming line cabinet secondary cabinet door, and sequentially connecting the two test cables into X3 and X4.
Step C4: and opening a secondary cabinet door of the steel rail potential limiting device, and sequentially connecting two test cables into X5 and X6.
Step C5: the other end of the test cable is connected with a signal synchronous test device.
Step C6: and restoring the power supply of the traction station so that the traction station is in a live running state.
Step C7: in the time T before the train starts to run, the signal synchronous testing device is powered to realize the signal testing of X1, X2, X3, X4, X5 and X6; t is arbitrarily valued within 10 minutes to 60 minutes. The signals obtained by the test are represented by S3, S4 and S5 in sequence.
Step C8: after the test is completed, the tested traction station is powered off, so that all electrical cabinets in the traction station are in a power-off state.
Step C9: and removing cables connected to the secondary cabinet door of the positive cabinet, the secondary cabinet door of the inversion incoming line cabinet and the secondary cabinet door of the steel rail potential limiting device, and powering off the signal synchronization testing device.
Step C10: after the test is completed, test data analysis is carried out, and output voltage and current of the rectifier unit are calculated; inverting the direct current of the energy feeder; rail potential.
Calculating the output current of the rectifier unit:
and D, calculating direct current side current of the inversion energy feed device:
and (3) calculating the potential of the steel rail:
therefore, the synchronous test of the electric quantity is realized by measuring the current and the voltage of the secondary side transmitter of the inversion inlet wire cabinet which is connected with the outgoing wire of the rectifier unit in series and the incoming wire of the inversion feedback device through the steel rail potential limiting device. The test method is safe and reliable, and the test data can be used for accurately verifying the rail potential simulation model.
Claims (2)
1. A multi-electric-quantity synchronous test method for a subway power supply system is characterized by comprising the following steps:
step A: acquiring current measurement loop drawings and voltage measurement loop drawings of an anode cabinet, an inversion incoming line cabinet and a steel rail potential limiting device in a traction substation;
and (B) step (B): determining the potential of the steel rail, the outgoing line current of the positive cabinet and the incoming line current of the inversion incoming line cabinet according to a voltage measurement loop drawing and a current measurement loop drawing, wherein the incoming line current of the inversion incoming line cabinet corresponds to a secondary test terminal;
step B1: and obtaining a corresponding test terminal of the positive cabinet according to the drawing and the terminal inquiry in the secondary cabinet door of the positive cabinet:
inquiring a current measurement loop drawing of the positive cabinet to obtain a current divider transformation ratio B1/B2 of an outgoing cable of the positive cabinet and serial numbers K1 and K2 of output ports of the current divider of the positive cabinet;
inquiring a current measuring loop drawing of the positive cabinet to obtain transformation ratios I1/I2 of the current transmitters corresponding to K1 and K2 and output port numbers X1 and X2 of the current transmitters;
opening a secondary cabinet door of the positive pole cabinet, and finding X1 and X2 according to the marks of all cables in the secondary chamber; x1 and X2 are positive cabinet outgoing line current test terminals;
step B2: according to the drawing and the terminal inquiry in the secondary cabinet door of the inversion incoming cabinet, the corresponding test terminal of the inversion incoming cabinet is obtained:
inquiring a current measurement loop drawing of the inversion incoming cabinet to obtain the transformation ratio B3/B4 of an incoming cable shunt of the inversion incoming cabinet and serial numbers K3 and K4 of output ports of the shunt of the inversion incoming cabinet;
inquiring a current measuring loop drawing of the inversion incoming line cabinet to obtain transformation ratios I3/I4 of current transmitters corresponding to K3 and K4 and output port numbers X3 and X4 of the current transmitters;
opening a secondary cabinet door of the inversion incoming line cabinet, and finding X3 and X4 according to the marks of all cables in the secondary cabinet; x3 and X4 are line-incoming current testing terminals of the inversion line-incoming cabinet;
step B3: obtaining a corresponding test terminal of the steel rail potential limiting device according to the drawing and the query of the terminal in the secondary cabinet door of the steel rail potential limiting device:
inquiring a voltage measurement loop drawing of the steel rail potential limiting device to obtain a shunt transformation ratio B5/B6 of a wiring cable connected with the steel rail in the steel rail potential limiting device and shunt output port numbers K5 and K6 of the shunt;
inquiring a voltage measurement loop drawing of the steel rail potential limiting device to obtain a transformation ratio U1/U2 of the voltage transmitter corresponding to K5 and K6 and output port numbers X5 and X6 of the voltage transmitter;
opening a secondary cabinet door of the steel rail potential limiting device, and finding X5 and X6 according to the marks of all cables in the secondary cabinet; x5 and X6 are rail potential test terminals of the rail potential limiting device;
step C: the electric cables are connected in parallel to the corresponding test terminals, the potential of the steel rail and the outgoing current of the positive cabinet are synchronously collected, and the incoming current of the incoming cabinet is inverted;
step C1: in order to ensure the safe and reliable wiring process, the measured traction station is powered off during the stop period of the subway train, so that all electrical cabinets in the traction station are in a power-off state;
step C2: opening a secondary cabinet door of the positive pole cabinet, and sequentially connecting two test cables into X1 and X2;
step C3: opening a secondary cabinet door of the inversion incoming line cabinet, and sequentially connecting two test cables into X3 and X4;
step C4: opening a secondary cabinet door of the steel rail potential limiting device, and sequentially connecting two test cables into X5 and X6;
step C5: the other end of the test cable is connected with a signal synchronous test device;
step C6: restoring the power supply of the traction station to enable the traction station to be in a live running state;
step C7: in the time T before the train starts to run, the signal synchronous testing device is powered to realize the signal testing of X1, X2, X3, X4, X5 and X6; the signals obtained by the test are represented by S3, S4 and S5 in sequence;
step C8: after the test is completed, the tested traction station is powered off, so that all electrical cabinets in the traction station are in a power-off state;
step C9: removing cables connected to the secondary cabinet door of the positive cabinet, the secondary cabinet door of the inversion incoming line cabinet and the secondary cabinet door of the steel rail potential limiting device, and powering off the signal synchronization testing device;
step C10: after the test is completed, carrying out test data analysis, and calculating to obtain the output current of the rectifier unit; inverting the direct current of the energy feeder; rail potential;
calculating the output current of the rectifier unit:
and D, calculating direct current side current of the inversion energy feed device:
and (3) calculating the potential of the steel rail:
2. the method for synchronously testing the multiple electric quantities of the subway power supply system according to claim 1, wherein the time T is arbitrarily valued within 10 minutes to 60 minutes.
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| CN105911391A (en) * | 2016-04-28 | 2016-08-31 | 中国铁建电气化局集团第工程有限公司 | RPLDECT rail potential limiting apparatus electrical apparatus characteristics tester |
| CN112924816A (en) * | 2021-02-02 | 2021-06-08 | 广州市扬新技术研究有限责任公司 | Direct current power flow on-line monitoring station measuring scheme of power supply network |
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| JP2003048465A (en) * | 2001-08-08 | 2003-02-18 | Mitsubishi Electric Corp | Leakage current detecting device for railway feeder circuit |
| JP6543587B2 (en) * | 2016-03-08 | 2019-07-10 | 西日本旅客鉄道株式会社 | High voltage earthing relay for DC railway substation |
| CN111579916A (en) * | 2019-09-23 | 2020-08-25 | 浙江得玛斯科技有限公司 | Direct current feeder cabinet line testing method |
| CN110780120B (en) * | 2019-10-17 | 2021-05-04 | 西南交通大学 | Urban rail transit direct current equipment insulation performance on-line monitoring system and control method |
| RU2725312C1 (en) * | 2019-11-08 | 2020-07-02 | Олег Сергеевич Шерстюков | Method to monitor conditions of station rail circuits |
| CN111596331A (en) * | 2020-04-17 | 2020-08-28 | 中铁建电气化局集团南方工程有限公司 | Comprehensive testing system and method for traction reflux and steel rail potential of electrified railway |
| CN113030658B (en) * | 2021-03-03 | 2023-09-15 | 珠海南自电气系统工程有限公司 | Stray current comprehensive monitoring system |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105911391A (en) * | 2016-04-28 | 2016-08-31 | 中国铁建电气化局集团第工程有限公司 | RPLDECT rail potential limiting apparatus electrical apparatus characteristics tester |
| CN112924816A (en) * | 2021-02-02 | 2021-06-08 | 广州市扬新技术研究有限责任公司 | Direct current power flow on-line monitoring station measuring scheme of power supply network |
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