CN111391893A

CN111391893A - Subway train position detection system

Info

Publication number: CN111391893A
Application number: CN202010122149.2A
Authority: CN
Inventors: 杨晓峰; 郑琼林; 顾靖达
Original assignee: Beijing Jiaotong University
Current assignee: Beijing Jiaotong University
Priority date: 2020-02-27
Filing date: 2020-02-27
Publication date: 2020-07-10
Anticipated expiration: 2040-02-27
Also published as: CN111391893B

Abstract

The invention belongs to the technical field of electrified rail transit and power electronic converters, and particularly relates to a subway train position detection system, which comprises: a plurality of first position detecting units and a plurality of second position detecting units. The first position detection unit and the second position detection unit work cooperatively to compare the product of the voltages output by the two position detection units, so as to judge the real-time dynamic position of the train. The invention has the advantages of dynamic real-time train position judgment, accurate positioning, good anti-interference performance, small maintenance amount and the like.

Description

Subway train position detection system

Technical Field

The invention relates to the technical field of electrified rail transit and power electronic converters, in particular to a subway train position detection system suitable for a traction power supply system for reducing the rail potential of a subway train.

Background

With the rapid development of subways, the maintenance amount of metal pipelines and steel bar building structures along the lines is remarkably increased. The method is fundamentally the problems of stray current and track potential caused by poor insulation of the subway steel rail. The traction power supply system for reducing the rail potential of the subway train, which is provided by the patent of 'a system for reducing the rail potential of the subway train', is also called as a negative resistance converter traction power supply system, and is an effective scheme for solving the problems from the source.

However, the negative resistance converter traction power supply system needs to accurately judge the train position, so as to ensure that the negative resistance converter and the switch unit operate correctly. However, the negative resistance converter system is independent of the existing line, and the following technical problems exist in the continuous use of the existing position detection system:

1. the sensitivity is high, and the train is easily interfered by an external magnetic field, so that the train positioning is inaccurate, and the normal work of a traction power supply system of the negative resistance converter is influenced.

2. The position information of the train is too sparse or dense, and the train positioning requirement of a negative resistance converter traction power supply system can not be met by depending on external monitoring equipment.

3. The negative resistance converter traction power supply system equipment misoperation caused by inaccurate positioning can generate adverse effects on the track potential reduction effect of the negative resistance converter traction power supply system.

Disclosure of Invention

Aiming at the technical problems in the prior art, the invention aims to provide a subway train position detection system, which can realize accurate dynamic real-time detection of the train position.

In order to achieve the above purposes, the technical scheme adopted by the invention is as follows:

a subway train position detection system is applied to the traction power supply system that reduces subway train track potential, includes: a plurality of first position detecting units and a plurality of second position detecting units;

the first terminal 51 of the first position detection unit is connected with the first terminal 71 of the negative resistance converter 7 or the first terminal 81 of the switch unit 8, and the second terminal 52 of the first position detection unit is connected with the running rail 4;

the first terminal 61 of the second position detection unit is connected to the running rail 4, and the second terminal 62 of the second position detection unit is connected to the first terminal 71 of the negative-impedance converter 7 or the first terminal 81 of the switching unit 8.

On the basis of the above scheme, the first position detection unit and the second position detection unit each include: a voltage sensor TV;

a positive terminal of the voltage sensor TV is connected to the first terminal 51 of the first position detection unit or the first terminal 61 of the second position detection unit; the negative terminal of the voltage sensor TV is connected to the second terminal 52 of the first position detection unit or the second terminal 62 of the second position detection unit; the output terminal of the voltage sensor TV is connected to the controller 10.

On the basis of the above scheme, the first position detection unit and the second position detection unit each include: a non-polar capacitor C and a voltage sensor TV;

one end of the non-polar capacitor C is connected with the positive terminal of the voltage sensor TV, and one end of the non-polar capacitor C is further connected with the first terminal 51 of the first position detection unit or the first terminal 61 of the second position detection unit; the other end of the non-polar capacitor C is connected to the negative terminal of the voltage sensor TV, and the other end of the non-polar capacitor C is further connected to the second terminal 52 of the first position detecting unit or the second terminal 62 of the second position detecting unit; the output terminal of the voltage sensor TV is connected to the controller 10.

On the basis of the above scheme, the first position detection unit and the second position detection unit each include: non-polar capacitor C₁,C₂,C₃,…,C_nVoltage sensor TV₁,TV₂,TV₃,…,TV_nAnd an adder, n is an integer > 1;

non-polar capacitor C₁,C₂,C₃,…,C_nRespectively corresponding voltage sensors TV₁,TV₂,TV₃,…,TV_nAfter being connected in parallel, the non-polar capacitor C is connected in series_nConnecting one end of other capacitor with voltage sensor TV_nThe positive terminal of (2) is connected; non-polar capacitor C_nThe other end of the capacitor is not connected with the voltage sensor TV_nNegative terminal of (2) a non-polar capacitor C_nThe other end of the capacitor not connected to the other capacitor is also connected to the second terminal 52 of the first position detecting unit or the second terminal 62 of the second position detecting unitVoltage sensor TV₁,TV₂,TV₃,…,TV_nThe output terminals of the adder are all connected with the input terminal of the adder; the output terminal of the adder is connected to the controller 10; non-polar capacitor C₁One end of the capacitor is not connected with the TV₁Is connected to the positive terminal of a non-polar capacitor C₁The other capacitor is not connected to the first terminal 51 of the first position detecting unit or the first terminal 61 of the second position detecting unit.

On the basis of the scheme, when a train 2 exists in a running rail section between the first position detection unit and the second position detection unit, the product of detection results of the first position detection unit and the second position detection unit is less than zero;

when a train 2 exists in a running rail section between the first position detection unit and the second position detection unit, the product of detection results of the first position detection unit and the second position detection unit is equal to zero, and the detection results of the first position detection unit or the second position detection unit are not equal to zero at the same time;

when the running rail section between the first position detection unit and the second position detection unit has no train 2, the product of the detection results of the first position detection unit and the second position detection unit is larger than zero; in a subway traction system with single-side power supply, when the product of adjacent position detection units of adjacent running rail sections is less than zero, no train exists between the two position detection units; when the detection results of the adjacent position detection units of the adjacent walking rail sections are zero at the same time, no train exists between the two position detection units; when the product of adjacent position detection units of adjacent walking rail sections is more than zero, a train is arranged between the two position detection units; the product of adjacent position detection units of adjacent running rail sections is equal to zero, the detection results of the adjacent position detection units are not equal to zero at the same time, and a train is arranged between the two position detection units.

When the running rail section between the first position detection unit and the second position detection unit has no train 2, the product of the detection results of the first position detection unit and the second position detection unit is equal to zero, and the detection results of the first position detection unit and the second position detection unit are equal to zero.

The invention has the beneficial effects that:

1. the method takes the pressure drop of the steel rail as a main judgment basis, has simple principle and good anti-interference performance, and can improve the positioning precision.

2. Independent of the existing line, the negative resistance converter traction power supply system is well matched with the negative resistance converter traction power supply system, the requirement of the negative resistance converter traction power supply system on train positioning is met, and the adverse effect of the negative resistance converter traction power supply system on reducing track potential is effectively avoided.

3. The equipment cost is low, the maintenance volume is low, the device is suitable for being arranged along the line, and the popularization and the application of a negative resistance converter traction power supply system are facilitated.

Drawings

The invention has the following drawings:

figure 1 is a schematic diagram of a negative-resistance converter traction power supply scheme,

figure 2 is a schematic diagram of a negative-resistance converter traction power supply scheme during train operation,

figure 3 is a schematic diagram of a traction power supply scheme II of the negative resistance converter,

figure 4 is a schematic diagram of a second traction power supply scheme of the negative resistance converter during the operation of the train,

figure 5 is a schematic diagram of a preferred embodiment of a first embodiment of the invention in combination with a negative-resistance converter traction power supply scheme,

figure 6 illustrates a preferred embodiment of the train in a traction-start condition in connection with scheme one,

figure 7 shows a schematic diagram of a preferred embodiment of the train traction starting operation in combination with the scheme one,

figure 8 illustrates a preferred embodiment of the train in combination with scheme one during regenerative braking conditions of the train figure one,

figure 9 shows a schematic diagram of a preferred embodiment of the train in a regenerative braking mode in combination with the first embodiment of the first embodiment,

figure 10 is a schematic diagram of a preferred embodiment of the invention in combination with a negative-resistance converter traction power supply scheme two,

figure 11 shows a preferred embodiment of the train traction start condition in combination with scheme two in figure one,

figure 12 shows a preferred embodiment of the train traction start condition in combination with scheme two in figure two,

figure 13 illustrates a preferred embodiment of a regenerative braking operation of the train in conjunction with scheme two in figure one,

figure 14 illustrates the preferred embodiment of the train in a regenerative braking mode in combination with scheme two figure two,

figure 15 a preferred embodiment of the structure of the position detection unit of the present invention is shown in figure one,

figure 16 a preferred embodiment of the structure of the position detecting unit of the present invention is shown in figure two,

figure 17 a preferred embodiment of the structure of the position detection unit of the present invention is shown in figure three,

FIG. 18 shows a preferred embodiment of an extended application of the present invention in FIG. one;

FIG. 19 shows a preferred embodiment of an extended application of the present invention in FIG. two.

Detailed Description

To describe the present invention more specifically, the technical solutions of the present invention will be described in more detail below with reference to the accompanying drawings and the embodiments. It should be emphasized that the following description is merely exemplary in nature and is not intended to limit the scope of the invention or its application.

As shown in fig. 1 and 2, in the first negative resistance converter traction power supply scheme, a subway traction power supply system adopts single-side power supply, and includes: the system comprises a traction substation 1, a contact net (or contact rail) 3, a walking rail 4, a negative resistance converter 7, a plurality of switch units 8 and a backflow cable 9, wherein the train 2 obtains energy through the contact net 3, the negative resistance converter 7, the plurality of switch units 8, the backflow cable 9 and the walking rail 4.

And a negative terminal 11 of the traction substation 1 is connected to the running rail 4, a positive terminal 12 of the traction substation 1 is connected to the overhead line system 3, and an alternating current terminal 13 of the traction substation 1 is connected to an alternating current input power supply or a secondary winding of the transformer. The traction substation 1 employs a multi-pulse rectifier device, and a typical multi-pulse rectifier device is a 24-pulse rectifier device.

The return cables 9 are arranged along the running rail 4, the first terminal 71 of the negative resistance converter 7 is connected with the running rail 4 and the negative terminal 11 of the traction substation 1, the second terminal 72 of the negative resistance converter 7 is connected with the return cables 9, and the switch units 8 are arranged in a plurality along the running rail 4.

In fig. 1 and 2, only one traction substation 1 in one power supply line (including the overhead line system 3, the running rail 4, the negative resistance converter 7, the switch unit 8, the return cable 9 and the like) transmits energy, so that the power supply line is called single-side power supply.

For example, when a train is running, the negative resistance converter traction power supply scheme is as shown in fig. 2: traction current i_tThe current flows into a contact network 3 from a positive terminal 12 of the traction substation 1, reaches a train 2, flows into a traveling rail 4 between the train 2 and a switch unit 8, flows back to a negative terminal 11 of the traction substation 1 through the switch unit 8, a return cable 9 and a negative resistance converter 7, and finally returns to the traction substation 1; forming a complete direct current single-side power supply loop.

As shown in fig. 3 and 4, in the second scheme of the negative resistance converter traction power supply, the subway traction power supply system adopts bilateral power supply, which includes: the system comprises a traction substation 1a, a traction substation 1b, a contact network (or a contact rail) 3, a traveling rail 4, a negative resistance converter 7a, a negative resistance converter 7b, a plurality of switch units 8 and a return cable 9, wherein the train 2 obtains energy through the contact network 3, the negative resistance converter 7a, the negative resistance converter 7b, the plurality of switch units 8, the return cable 9 and the traveling rail 4.

And the negative terminals 11 of the traction substation 1a and the traction substation 1b are connected to the walking rail 4, the positive terminals 12 of the traction substation 1a and the traction substation 1b are connected to the overhead line system 3, and the alternating current terminals 13 of the traction substation 1a and the traction substation 1b are connected to an alternating current input power supply or a secondary winding of the transformer. The traction substation 1 employs a multi-pulse rectifier device, and a typical multi-pulse rectifier device is a 24-pulse rectifier device.

The return cables 9 are arranged along the running rail 4, first terminals 71 of the

negative resistance converters

7a and 7b are connected with the running rail 4 and the negative electrode terminal 11 of the traction substation 1, second terminals 72 of the

negative resistance converters

7a and 7b are connected with the return cables 9, and the switch units 8 are arranged in a plurality of numbers along the running rail 4.

In fig. 3 and 4, two ends of a section of power supply line (including a contact line 3, a traveling rail 4, a negative resistance converter 7, a switch unit 8, a return cable 9 and the like) are respectively provided with a traction substation 1 for transmitting energy, so that the power supply line is called bilateral power supply.

Taking a train running as an example, the second negative resistance converter traction power supply scheme is shown in fig. 4: traction current i_t1The current flows into a contact network 3 from a positive terminal 12 of the traction substation 1a, reaches a train 2, flows into a traveling rail 4 between the train 2 and a switch unit 8, flows back to a negative terminal 11 of the traction substation 1a through the switch unit 8, a return cable 9 and a negative resistance converter 7a, and finally returns to the traction substation 1 a;

at the same time, a traction current i_t2The current flows into a contact network 3 from a positive terminal 12 of the traction substation 1b, reaches the train 2, flows into a traveling rail 4 between the train 2 and the switch unit 8, flows back to a negative terminal 11 of the traction substation 1b through the switch unit 8, the return cable 9 and the negative resistance converter 7b, and finally returns to the traction substation 1 b; the two parts of power supply loops form a complete direct current bilateral power supply loop together.

Aiming at the negative resistance converter traction power supply scheme shown in the figures 1, 2, 3 and 4, the invention adopts a subway train position detection scheme: the device comprises a plurality of first position detection units and a plurality of second position detection units;

the first terminal 51 of the first position detection unit is connected with the first terminal 71 of the negative resistance converter 7 or the first terminal 81 of the switch unit 8, and the second terminal 52 of the first position detection unit is connected with the running rail 4 after a certain distance;

the second terminal 62 of the second position detection unit is connected with the first terminal 71 of the negative resistance converter 7 or the first terminal 81 of the switch unit 8, and the first terminal 61 of the second position detection unit is connected with the running rail 4 after a certain distance;

the first combination scheme is a single-side power supply scheme as shown in fig. 5, 6, 7, 8 and 9,

the second combination scheme is a bilateral power supply scheme as shown in fig. 10, fig. 11, fig. 12, fig. 13 and fig. 14.

For convenience of explaining the operating principle of the first combination scheme and the second combination scheme, in the first combination scheme shown in fig. 6, 7, 8 and 9 and the second combination scheme shown in fig. 11, 12, 13 and 14, three switch units 8 are provided as an example, and are respectively denoted as

switch units

8a, 8b and 8 c.

The traction substation 1 employs a multi-pulse rectifier device, and a typical multi-pulse rectifier device is a 24-pulse rectifier device.

The first combination scheme is shown in fig. 5, and the specific connection mode is as follows:

the negative terminals 11 of the traction substation 1 are all connected to the walking rails 4, the positive terminals 12 of the traction substation 1 are all connected to the contact network 3, and the alternating current terminals 13 of the traction substation 1 are all connected with an alternating current input power supply or a secondary winding of a transformer;

the first terminal 71 of the negative resistance converter 7 is connected to the negative terminal 11 of the traction substation 1, and the second output terminal 72 of the negative resistance converter 7 is connected to the return cable 9; a first terminal 81 of the switching unit 8 is connected to the running rail 4 and a second terminal 82 of the switching unit 8 is connected to the return cable 9.

The working process of the combination scheme I is as follows:

as shown in fig. 6, when there is a train 2 running on the running rail 4 (the train 2 is in the traction condition and located between the switch unit 8b and the switch unit 8 c), the current flow path in the negative resistance converter traction power supply system is: current i output from traction substation 1_tThe positive terminal 12 of the traction substation 1 is transmitted to a contact net 3 and transmitted to the train 2 through the contact net 3;

the current returned from the train 2 to the traction substation 1 is transmitted to the running rail 4 through the train 2, transferred to the return cable 9 through the switch unit 8b and the switch unit 8c, transferred to the negative terminal 11 of the traction substation 1 through the negative resistance converter 7, and finally returned to the traction substation 1.

In the process, the current i flowing through the running rail 4 of the first running rail section in parallel with the first position detection unit 5a₁The direction is as follows: from the second terminal 52 of the first position detection unit 5a to the first terminal 51 of the first position detection unit 5a, the voltage detected by the voltage sensor in the first position detection unit 5a is less than or equal to zero, and the current i flowing through the running rail 4 of the first running rail section in parallel with the second position detection unit 6a₂The direction is as follows: from the second terminal 62 to the second position detecting unit 6aA first terminal 61 of the second position detection unit 6a, a voltage detected by the voltage sensor in the second position detection unit 6a being less than or equal to zero;

the current i flowing through the running rail 4 of the second running rail section in parallel with the first position detection unit 5b₃The direction is as follows: from the second terminal 52 of the first position detection unit 5b to the first terminal 51 of the first position detection unit 5b, the voltage detected by the voltage sensor in the first position detection unit 5b is less than or equal to zero, and the current i flowing through the running rail 4 of the second running rail section in parallel with the second position detection unit 6b₄The direction is as follows: from the second terminal 62 of the second position detecting unit 6b to the first terminal 61 of the second position detecting unit 6b, the voltage detected by the voltage sensor in the second position detecting unit 6b is less than or equal to zero;

the current i flowing through the running rail 4 of the third running rail section in parallel with the first position detection unit 5c₅The direction is as follows: from the second terminal 52 of the first position detection unit 5c to the first terminal 51 of the first position detection unit 5c, the voltage detected by the voltage sensor in the first position detection unit 5c is less than zero; the current i flowing through the running rail 4 of the third running rail section connected in parallel with the second position detection unit 6c₆The direction is as follows: from the first terminal 61 of the second position detecting unit 6c to the second terminal 62 of the second position detecting unit 6c, the voltage detected by the voltage sensor in the second position detecting unit 6c is greater than zero;

the voltage information is transmitted to the controller 10 through a communication loop, and the controller 10 judges the voltages and the product of the voltages of the first position detection unit and the second position detection unit in the same running rail section: a train is arranged between the two position detection units with the product smaller than zero, the voltage of the first position detection unit is smaller than zero, and the voltage of the second position detection unit is larger than zero, so that the train is in a traction working condition or a working condition similar to the traction working condition principle; a train is arranged between the two position detection units with the product smaller than zero, the voltage of the first position detection unit is larger than zero, the voltage of the second position detection unit is smaller than zero, and the train is in a regeneration working condition or a working condition similar to the regeneration working condition principle; a train is arranged between the two position detection units with the product equal to zero and one voltage value smaller than zero, and the train is in a traction working condition or a working condition similar to the traction working condition principle; a train is arranged between the two position detection units with the product equal to zero and one voltage value larger than zero, and the train is in a regeneration working condition or a working condition similar to the regeneration working condition principle; no train exists between the two position detection units with the product larger than zero; and no train is arranged between the two position detection units, the product of which is equal to zero and the two voltage values of which are zero.

The controller 10 determines the voltage and the product of the voltages of the adjacent second position detection unit and the adjacent first position detection unit of the adjacent running rail section: a train is arranged between the two position detection units with the product larger than zero, the voltage of the second position detection unit is smaller than zero, and the voltage of the first position detection unit is smaller than zero, so that the train is in a traction working condition or a working condition similar to the traction working condition principle; a train is arranged between the two position detection units with the product larger than zero, the voltage of the second position detection unit is larger than zero, and the voltage of the first position detection unit is larger than zero, so that the train is in a regeneration working condition or a working condition similar to the regeneration working condition principle; a train is arranged between the two position detection units with the product equal to zero and one voltage value smaller than zero, and the train is in a traction working condition or a working condition similar to the traction working condition principle; a train is arranged between the two position detection units with the product equal to zero and one voltage value larger than zero, and the train is in a regeneration working condition or a working condition similar to the regeneration working condition principle; no train exists between the two position detection units with the product less than zero; and no train is arranged between the two position detection units, the product of which is equal to zero and the two voltage values of which are zero.

According to the train position information and the train working condition information, the controller 10 outputs a control signal to regulate and control the working states of the negative resistance converter 7 and the switch unit 8.

As shown in fig. 7, when a train 2 runs on the running rail 4 (the train 2 is in a traction condition and is located between the traction substation 1 and the switch unit 8 a), the current flow path in the negative resistance converter traction power supply system is as follows: current i output from traction substation 1_tThe positive terminal 12 of the traction substation 1 is transmitted to a contact net 3 and transmitted to the train 2 through the contact net 3;

the current returned from the train 2 to the traction substation 1 is transmitted to the running rail 4 through the train 2, part of the current is transferred to the return cable 9 through the switch unit 8a, then transferred to the negative terminal 11 of the traction substation 1 through the negative resistance converter 7, and returned to the traction substation 1; the other part of the current directly flows back to the negative terminal 11 of the traction substation 1 through the traveling rail 4 and finally returns to the traction substation 1.

In the process, the current i flowing through the running rail 4 of the first running rail section in parallel with the first position detection unit 5a₁The direction is as follows: from the second terminal 52 of the first position detection unit 5a to the first terminal 51 of the first position detection unit 5a, the voltage detected by the voltage sensor in the first position detection unit 5a is less than zero; the current i flowing through the running rail 4 of the first running rail section in parallel with the second position detection unit 6a₂The direction is as follows: from the first terminal 61 of the second position detecting unit 6a to the second terminal 62 of the second position detecting unit 6a, the voltage detected by the voltage sensor in the second position detecting unit 6a is greater than zero;

the current i flowing through the running rail 4 of the second running rail section in parallel with the first position detection unit 5b₃Equal to zero, the voltage detected by the voltage sensor in the first position detection unit 5b is equal to zero, and the current i flowing through the running rail 4 of the second running rail section in parallel with the second position detection unit 6b is equal to zero₄Equal to zero, the voltage detected by the voltage sensor in the second position detection unit 6b is equal to zero;

the current i flowing through the running rail 4 of the third running rail section in parallel with the first position detection unit 5c₅Equal to zero, the voltage detected by the voltage sensor in the first position detection unit 5c is equal to zero, and the current i flowing through the running rail 4 of the third running rail section in parallel with the second position detection unit 6c₆Equal to zero, the voltage detected by the voltage sensor in the second position detection unit 6c is equal to zero;

As shown in fig. 8, when there is a train 2 running on the running rail 4 (the train 2 is in the regeneration condition and located between the switch unit 8b and the switch unit 8 c), the current flow path in the negative resistance converter traction power supply system is: current i output from train 2_tAnd transmitted to the positive terminal 12 of the traction substation 1 through the overhead line system 3;

the current returned from the traction substation 1 to the train 2 is first transmitted to the running rail 4 through the capacitor of the traction substation 1 and the like, transferred to the return cable 9 through the negative resistance converter 7, then transferred to the train 2 through the switching

units

8b and 8c, and finally returned to the train 2.

In the process, the current i flowing through the running rail 4 of the first running rail section in parallel with the first position detection unit 5a₁The direction is as follows: from the first terminal 51 of the first position detection unit 5a to the second terminal 52 of the first position detection unit 5a, the voltage detected by the voltage sensor in the first position detection unit 5a is greater than or equal to zero, and the current i flowing through the running rail 4 of the first running rail section in parallel with the second position detection unit 6a₂The direction is as follows: from the first terminal 61 of the second position detecting unit 6a to the second terminal 62 of the second position detecting unit 6a, the voltage detected by the voltage sensor in the second position detecting unit 6a is greater than or equal to zero;

the current i flowing through the running rail 4 of the second running rail section in parallel with the first position detection unit 5b₃The direction is as follows: from the first terminal 51 of the first position detection unit 5b to the second terminal 52 of the first position detection unit 5b, the voltage detected by the voltage sensor in the first position detection unit 5b is greater than or equal to zero, and the current i flowing through the running rail 4 of the second running rail section in parallel with the second position detection unit 6b₄The direction is as follows: from the first terminal 61 of the second position detecting unit 6b to the second terminal 62 of the second position detecting unit 6b, the voltage detected by the voltage sensor in the second position detecting unit 6b is greater than or equal to zero;

the current i flowing through the running rail 4 of the third running rail section in parallel with the first position detection unit 5c₅The direction is as follows: from the first terminal 51 of the first position detecting unit 5c to the first position detectionA second terminal 52 of the detecting unit 5c, the voltage detected by the voltage sensor in the first position detecting unit 5c being greater than zero; the current i flowing through the running rail 4 of the third running rail section connected in parallel with the second position detection unit 6c₆The direction is as follows: from the second terminal 62 of the second position detecting unit 6c to the first terminal 61 of the second position detecting unit 6c, the voltage detected by the voltage sensor in the second position detecting unit 6c is less than zero;

As shown in fig. 9, when a train 2 runs on the running rail 4 (the train 2 is in a regeneration condition and is located between the traction substation 1 and the switch unit 8 a), the current flow path in the negative resistance converter traction power supply system is as follows: current i output from train 2_tAnd transmitted to the positive terminal 12 of the traction substation 1 through the overhead line system 3;

the current returned from the traction substation 1 to the train 2 is first transmitted to the running rail 4 through the capacitor of the traction substation 1 and the like, transferred to the return cable 9 through the negative resistance converter 7, transferred to the train 2 through the switching unit 8a, and finally returned to the train 2.

In the process, the current i flowing through the running rail 4 of the first running rail section in parallel with the first position detection unit 5a₁The direction is as follows: from the first terminal 51 of the first position detection unit 5a to the second terminal 52 of the first position detection unit 5a, the voltage detected by the voltage sensor in the first position detection unit 5a is greater than zero; the current i flowing through the running rail 4 of the first running rail section in parallel with the second position detection unit 6a₂The direction is as follows: from the second terminal 62 of the second position detecting unit 6a to the first terminal 61 of the second position detecting unit 6a, the voltage detected by the voltage sensor in the second position detecting unit 6a is less than zero;

the current i flowing through the running rail 4 of the second running rail section in parallel with the first position detection unit 5b₃Equal to zero, voltage in the first position detection unit 5bThe voltage detected by the sensor is equal to zero and the current i flowing through the running rail 4 of the second running rail section connected in parallel with the second position detection unit 6b₄Equal to zero, the voltage detected by the voltage sensor in the second position detection unit 6b is equal to zero;

The second combination scheme is shown in fig. 10, and the specific connection mode is as follows:

the negative terminals 11 of the traction substation 1a and the traction substation 1b are connected to the walking rail 4, the positive terminals 12 of the traction substation 1a and the traction substation 1b are connected to the contact network 3, and the alternating current terminals 13 of the traction substation 1a and the traction substation 1b are connected to an alternating current input power supply or a secondary winding of a transformer;

the first terminal 71 of the negative resistance converter 7a is connected to the negative terminal 11 of the traction substation 1a, the first terminal 71 of the negative resistance converter 7b is connected to the negative terminal 11 of the traction substation 1b, and the second output terminals 72 of the negative resistance converter 7a and the negative resistance converter 7b are both connected to the return cable 9; a first terminal 81 of the switching unit 8 is connected to the running rail 4 and a second terminal 82 of the switching unit 8 is connected to the return cable 9.

The working process of the combination scheme II is as follows:

as shown in fig. 11, when there is a train 2 running on the running rail 4 (the train 2 is in the traction condition and located between the switch unit 8b and the switch unit 8 c), the current flow path in the negative resistance converter traction power supply system is: current i output from traction substation 1a_t1The signal is transmitted to a contact net 3 through a positive terminal 12 of the traction substation 1a and is transmitted to the train 2 through the contact net 3; current i output from traction substation 1b_t2The signal is transmitted to a contact net 3 through a positive terminal 12 of the traction substation 1b and transmitted to the train 2 through the contact net 3;

the current returned from the train 2 to the traction substation 1 is transmitted to the running rail 4 through the train 2, transferred to the return cable 9 through the switch unit 8b and the switch unit 8c, transferred to the negative terminals 11 of the traction substation 1a and the traction substation 1b through the negative resistance converter 7a and the negative resistance converter 7b, and finally returned to the traction substation 1.

In the process, the current i flowing through the running rail 4 of the first running rail section in parallel with the first position detection unit 5a₁The direction is as follows: from the second terminal 52 of the first position detection unit 5a to the first terminal 51 of the first position detection unit 5a, the voltage detected by the voltage sensor in the first position detection unit 5a is less than or equal to zero, and the current i flowing through the running rail 4 of the first running rail section in parallel with the second position detection unit 6a₂The direction is as follows: from the second terminal 62 of the second position detecting unit 6a to the first terminal 61 of the second position detecting unit 6a, the voltage detected by the voltage sensor in the second position detecting unit 6a is less than or equal to zero;

the current i flowing through the running rail 4 of the third running rail section in parallel with the first position detection unit 5c₅The direction is as follows: from the second terminal 52 of the first position detection unit 5c to the second terminal of the first position detection unit 5cA terminal 51 at which the voltage detected by the voltage sensor in the first position detection unit 5c is less than zero; the current i flowing through the running rail 4 of the third running rail section connected in parallel with the second position detection unit 6c₆The direction is as follows: from the first terminal 61 of the second position detecting unit 6c to the second terminal 62 of the second position detecting unit 6c, the voltage detected by the voltage sensor in the second position detecting unit 6c is greater than zero;

the current i flowing through the running rail 4 of the fourth running rail section connected in parallel with the first position detection unit 5d₇The direction is as follows: from the first terminal 51 of the first position detection unit 5d to the second terminal 52 of the first position detection unit 5d, the voltage detected by the voltage sensor in the first position detection unit 5d is greater than or equal to zero, and the current i flowing through the running rail 4 of the fourth running rail section in parallel with the second position detection unit 6d₈The direction is as follows: from the first terminal 61 of the second position detecting unit 6d to the second terminal 62 of the second position detecting unit 6d, the voltage detected by the voltage sensor in the second position detecting unit 6d is greater than or equal to zero;

the voltage information is transmitted to the controller 10 through a communication loop, and the controller 10 judges the voltages and the product of the voltages of the first position detection unit and the second position detection unit in the same running rail section: no train exists between the two position detection units with the product being greater than or equal to zero; a train is arranged between the two position detection units with the product smaller than zero, the voltage of the first position detection unit is smaller than zero, and the voltage of the second position detection unit is larger than zero, so that the train is in a traction working condition or a working condition similar to the traction working condition principle; and a train is arranged between the two position detection units with the product smaller than zero, the voltage of the first position detection unit is larger than zero, and the voltage of the second position detection unit is smaller than zero, so that the train is in a regeneration working condition or a working condition similar to the regeneration working condition principle.

The controller 10 determines the voltage and the product of the voltages of the adjacent second position detection unit and the adjacent first position detection unit of the adjacent running rail section: no train exists between the two position detection units with the product being greater than or equal to zero; a train is arranged between the two position detection units with the product smaller than zero, the voltage of the second position detection unit is smaller than zero, and the voltage of the first position detection unit is larger than zero, so that the train is in a traction working condition or a working condition similar to the traction working condition principle; and a train is arranged between the two position detection units with the product smaller than zero, the voltage of the second position detection unit is larger than zero, and the voltage of the first position detection unit is smaller than zero, so that the train is in a regeneration working condition or a working condition similar to the regeneration working condition principle.

As shown in fig. 12, when a train 2 runs on the running rail 4 (the train 2 is in a traction condition and is located between the traction substation 1a and the switch unit 8 a), the current flow path in the negative resistance converter traction power supply system is as follows: current i output from traction substation 1a_t1The signal is transmitted to a contact net 3 through a positive terminal 12 of the traction substation 1a and is transmitted to the train 2 through the contact net 3; current i output from traction substation 1b_t2The signal is transmitted to a contact net 3 through a positive terminal 12 of the traction substation 1b and transmitted to the train 2 through the contact net 3;

the current returned from the train 2 to the traction substation 1 is transmitted to the running rail 4 through the train 2, part of the current is transferred to the return cable 9 through the switch unit 8a, and then transferred to the negative terminals 11 of the traction substation 1a and the traction substation 1b through the negative resistance converter 7a and the negative resistance converter 7b, and returned to the traction substation 1; the other part of the current directly flows back to the negative terminal 11 of the traction substation 1a through the running rail 4, and finally returns to the traction substation 1.

In the process, the current i flowing through the running rail 4 of the first running rail section in parallel with the first position detection unit 5a₁The direction is as follows: from the second terminal 52 of the first position detection unit 5a to the first terminal 51 of the first position detection unit 5a, the voltage detected by the voltage sensor in the first position detection unit 5a is less than zero; the current i flowing through the running rail 4 of the first running rail section in parallel with the second position detection unit 6a₂The direction is as follows: from the first terminal 61 of the second position detecting unit 6a to the second terminal 62 of the second position detecting unit 6a, detected by the voltage sensor in the second position detecting unit 6aThe voltage is greater than zero;

the current i flowing through the running rail 4 of the third running rail section in parallel with the first position detection unit 5c₅The direction is as follows: from the first terminal 51 of the first position detection unit 5c to the second terminal 52 of the first position detection unit 5c, the voltage detected by the voltage sensor in the first position detection unit 5c is greater than or equal to zero, and the current i flowing through the running rail 4 of the third running rail section in parallel with the second position detection unit 6c₆The direction is as follows: from the first terminal 61 of the second position detecting unit 6c to the second terminal 62 of the second position detecting unit 6c, the voltage detected by the voltage sensor in the second position detecting unit 6c is greater than or equal to zero;

As shown in fig. 13, when there is a train 2 running on the running rail 4 (the train 2 is in the regeneration condition and located between the switch unit 8b and the switch unit 8 c), the current flow path in the negative resistance converter traction power supply system is: current i output from train 2_t1And transmitted to the positive terminal 12 of the traction substation 1a through the overhead line system 3; current i output from train 2_t2And is transmitted to a positive terminal 12 of the traction substation 1b through a contact network 3;

the current returned from the traction substation 1 to the train 2 is first transmitted to the running rail 4 by the capacitor of the traction substation 1, and then transferred to the return cable 9 via the negative resistance converter 7a and the negative resistance converter 7b, and then transferred to the train 2 by the switch unit 8b and the switch unit 8c, and finally returned to the train 2.

the current i flowing through the running rail 4 of the third running rail section in parallel with the first position detection unit 5c₅The direction is as follows: from the first terminal 51 of the first position detection unit 5c to the second terminal 52 of the first position detection unit 5c, the voltage detected by the voltage sensor in the first position detection unit 5c is greater than zero; the current i flowing through the running rail 4 of the third running rail section connected in parallel with the second position detection unit 6c₆The direction is as follows: from the second terminal 62 of the second position detecting unit 6c to the first terminal 61 of the second position detecting unit 6c, the voltage detected by the voltage sensor in the second position detecting unit 6c is less than zero;

the current i flowing through the running rail 4 of the fourth running rail section connected in parallel with the first position detection unit 5d₇The direction is as follows: from the first position detecting unit 5dA second terminal 52 to a first terminal 51 of a first position-detecting unit 5d, the voltage detected by a voltage sensor in the first position-detecting unit 5d being less than or equal to zero, a current i flowing through the running rail 4 of the fourth running rail section in parallel with the second position-detecting unit 6d₈The direction is as follows: from the second terminal 62 of the second position detecting unit 6d to the first terminal 61 of the second position detecting unit 6d, the voltage detected by the voltage sensor in the second position detecting unit 6d is less than or equal to zero;

As shown in fig. 14When a train 2 runs on the running rail 4 (the train 2 is in a regeneration working condition and is positioned between the traction substation 1a and the switch unit 8 a), the current flow path in the traction power supply system of the negative resistance converter is as follows: current i output from train 2_t1And transmitted to the positive terminal 12 of the traction substation 1a through the overhead line system 3; current i output from train 2_t2And is transmitted to a positive terminal 12 of the traction substation 1b through a contact network 3;

the current returned from the traction substation 1 to the train 2 is first transmitted to the running rail 4 by the capacitor of the traction substation 1, and then transferred to the return cable 9 via the negative resistance converter 7a and the negative resistance converter 7b, and then transferred to the train 2 by the switching unit 8a, and finally returned to the train 2.

the current i flowing through the running rail 4 of the third running rail section in parallel with the first position detection unit 5c₅The direction is as follows: from the first position detecting unit5c to a first terminal 51 of a first position-detecting unit 5c, the voltage detected by the voltage sensor in the first position-detecting unit 5c being less than or equal to zero, the current i flowing through the running rail 4 of the third running rail section in parallel with the second position-detecting unit 6c₆The direction is as follows: from the second terminal 62 of the second position detecting unit 6c to the first terminal 61 of the second position detecting unit 6c, the voltage detected by the voltage sensor in the second position detecting unit 6c is less than or equal to zero;

the current i flowing through the running rail 4 of the fourth running rail section connected in parallel with the first position detection unit 5d₇The direction is as follows: from the second terminal 52 of the first position detection unit 5d to the first terminal 51 of the first position detection unit 5d, the voltage detected by the voltage sensor in the first position detection unit 5d is less than or equal to zero, and the current i flowing through the running rail 4 of the fourth running rail section in parallel with the second position detection unit 6d₈The direction is as follows: from the second terminal 62 of the second position detecting unit 6d to the first terminal 61 of the second position detecting unit 6d, the voltage detected by the voltage sensor in the second position detecting unit 6d is less than or equal to zero;

As shown in fig. 15, the first position detection unit and the second position detection unit each include: a voltage sensor TV;

the positive terminal of the voltage sensor TV is connected to the first terminal 51 of the first position detection unit or the first terminal 61 of the second position detection unit; the negative terminal of the voltage sensor TV is connected to the second terminal 52 of the first position detection unit or the second terminal 62 of the second position detection unit; the output terminal of the voltage sensor TV is connected to the controller 10;

as shown in fig. 16, the first position detection unit and the second position detection unit each include: a non-polar capacitor C and a voltage sensor TV;

one end of the non-polar capacitor C is connected with the positive terminal of the voltage sensor TV, and one end of the non-polar capacitor C is further connected with the first terminal 51 of the first position detection unit or the first terminal 61 of the second position detection unit; the other end of the non-polar capacitor C is connected to the negative terminal of the voltage sensor TV, and the other end of the non-polar capacitor C is further connected to the second terminal 52 of the first position detecting unit or the second terminal 62 of the second position detecting unit; the output terminal of the voltage sensor TV is connected to the controller 10;

as shown in fig. 17, the first position detection unit and the second position detection unit each include: non-polar capacitor C₁,C₂,C₃,…,C_nVoltage sensor TV₁,TV₂,TV₃,…,TV_nAnd an adder, n is an integer > 1;

non-polar capacitor C₁,C₂,C₃,…,C_nRespectively associated with a voltage sensor TV₁,TV₂,TV₃,…,TV_nAfter being connected in parallel, the non-polar capacitor C is connected in series_nConnecting one end of other capacitor with voltage sensor TV_nThe positive terminal of (2) is connected; non-polar capacitor C_nThe other end of the capacitor is not connected with the voltage sensor TV_nNegative terminal of (2) a non-polar capacitor C_nThe other end of the capacitor not connected to the other capacitor is connected to the second terminal 52 of the first position detecting unit or the second terminal 62 of the second position detecting unit, and the voltage sensor TV₁,TV₂,TV₃,…,TV_nThe output terminals of the adder are all connected with the input terminal of the adder; the output terminal of the adder is connected to the controller 10; non-polar capacitor C₁One end of the capacitor is not connected with the TV₁Is connected to the positive terminal of a non-polar capacitor C₁The other capacitor is not connected to the first terminal 51 of the first position detecting unit or the first terminal 61 of the second position detecting unit.

FIG. 18 is a schematic diagram of the preferred embodiment of the extended application of the present invention; when the number of power supply intervals of the traction power supply system is increased, the walking rails are connected through a flow equalizing line, and the uplink and downlink lines are provided with position detection devices: the voltage information of the first position detection unit and the second position detection unit is transmitted to the controller 10 through the communication loop, and the controller 10 judges the voltage and the product of the voltage of the first position detection unit and the voltage of the second position detection unit in the same traveling rail section: no train exists between the two position detection units with the product being greater than or equal to zero; a train is arranged between the two position detection units with the product smaller than zero, the voltage of the first position detection unit is smaller than zero, and the voltage of the second position detection unit is larger than zero, so that the train is in a traction working condition or a working condition similar to the traction working condition principle; and a train is arranged between the two position detection units with the product smaller than zero, the voltage of the first position detection unit is larger than zero, and the voltage of the second position detection unit is smaller than zero, so that the train is in a regeneration working condition or a working condition similar to the regeneration working condition principle.

FIG. 19 is a schematic diagram of a preferred embodiment of the extended application of the present invention; when the number of power supply intervals of the traction power supply system is increased, the walking rails are connected through a current-sharing line, and an uplink line and a downlink line share the position detection device: the voltage information of the first position detection unit and the second position detection unit is transmitted to the controller 10 through the communication loop, and the controller 10 judges the voltage and the product of the voltage of the first position detection unit and the voltage of the second position detection unit in the same traveling rail section: no train exists between the two position detection units with the product being greater than or equal to zero; a train is arranged between the two position detection units with the product smaller than zero, the voltage of the first position detection unit is smaller than zero, and the voltage of the second position detection unit is larger than zero, so that the train is in a traction working condition or a working condition similar to the traction working condition principle; and a train is arranged between the two position detection units with the product smaller than zero, the voltage of the first position detection unit is larger than zero, and the voltage of the second position detection unit is smaller than zero, so that the train is in a regeneration working condition or a working condition similar to the regeneration working condition principle.

The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope of the present invention are included in the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.

Those not described in detail in this specification are within the skill of the art.

Claims

1. The utility model provides a subway train position detecting system, its characterized in that is applied to and reduces tractive power supply system of subway train track potential, includes: a plurality of first position detecting units and a plurality of second position detecting units;

a first terminal (51) of the first position detection unit is connected with a first terminal (71) of the negative resistance converter (7) or a first terminal (81) of the switch unit (8), and a second terminal (52) of the first position detection unit is connected with the running rail (4);

the first terminal (61) of the second position detection unit is connected to the running rail (4), and the second terminal (62) of the second position detection unit is connected to the first terminal (71) of the negative-resistance converter (7) or the first terminal (81) of the switching unit (8).

2. The subway train position detecting system as claimed in claim 1, wherein said first position detecting unit and said second position detecting unit each comprise: a voltage sensor TV;

a positive terminal of the voltage sensor TV is connected to a first terminal (51) of the first position detection unit or a first terminal (61) of the second position detection unit; a negative terminal of the voltage sensor TV is connected to the second terminal (52) of the first position detection unit or the second terminal (62) of the second position detection unit; the output terminal of the voltage sensor TV is connected to a controller (10).

3. The subway train position detecting system as claimed in claim 1, wherein said first position detecting unit and said second position detecting unit each comprise: a non-polar capacitor C and a voltage sensor TV;

one end of the non-polar capacitor C is connected with the positive terminal of the voltage sensor TV, and one end of the non-polar capacitor C is also connected with the first terminal (51) of the first position detection unit or the first terminal (61) of the second position detection unit; the other end of the non-polar capacitor C is connected with a negative electrode terminal of the voltage sensor TV, and the other end of the non-polar capacitor C is also connected with a second terminal (52) of the first position detection unit or a second terminal (62) of the second position detection unit; the output terminal of the voltage sensor TV is connected to a controller (10).

4. The subway train position detecting system as claimed in claim 1, wherein said first position detecting unit and said second position detecting unit each comprise: non-polar capacitor C₁,C₂,C₃,…,C_nVoltage sensor TV₁,TV₂,TV₃,…,TV_nAnd an adder, n is an integer > 1;

non-polar capacitor C₁,C₂,C₃,…,C_nRespectively corresponding voltage sensors TV₁,TV₂,TV₃,…,TV_nAfter being connected in parallel, the non-polar capacitor C is connected in series_nConnecting one end of other capacitor with voltage sensor TV_nThe positive terminal of (2) is connected; non-polar capacitor C_nIs not connected toThe other end connected with other capacitor and the voltage sensor TV_nNegative terminal of (2) a non-polar capacitor C_nThe other end of the capacitor is connected to the second terminal (52) of the first position detecting unit or the second terminal (62) of the second position detecting unit, and the voltage sensor TV₁,TV₂,TV₃,…,TV_nThe output terminals of the adder are all connected with the input terminal of the adder; the output terminal of the adder is connected with the controller (10); non-polar capacitor C₁One end of the capacitor is not connected with the TV₁Is connected to the positive terminal of a non-polar capacitor C₁The end to which the other capacitor is not connected is also connected to the first terminal (51) of the first position detection unit or the first terminal (61) of the second position detection unit.

5. A subway train position detection system as claimed in any one of claims 2-4, wherein when there is a train (2) in the running rail section between the first position detection unit and the second position detection unit, the product of the detection results of the first position detection unit and the second position detection unit is less than zero;

when a train (2) exists in a running rail section between the first position detection unit and the second position detection unit, the product of the detection results of the first position detection unit and the second position detection unit is equal to zero, and the detection results of the first position detection unit or the second position detection unit are not equal to zero at the same time;

when no train (2) exists in a running rail section between the first position detection unit and the second position detection unit, the product of the detection results of the first position detection unit and the second position detection unit is larger than zero; in a subway traction system with single-side power supply, when the product of adjacent position detection units of adjacent running rail sections is less than zero, no train exists between the two position detection units; when the detection results of the adjacent position detection units of the adjacent walking rail sections are zero at the same time, no train exists between the two position detection units; when the product of adjacent position detection units of adjacent walking rail sections is more than zero, a train is arranged between the two position detection units; the product of adjacent position detection units of adjacent walking rail sections is equal to zero, the detection results of the adjacent position detection units are not equal to zero at the same time, and a train is arranged between the two position detection units;

when no train (2) exists in a running rail section between the first position detection unit and the second position detection unit, the product of the detection results of the first position detection unit and the second position detection unit is equal to zero, and the detection results of the first position detection unit and the second position detection unit are equal to zero.