A method for starting and controlling a rail potential limiting device considering the status of a shield door

Abstract

The present invention discloses a method for starting and controlling a rail potential limiting device taking into account the status of a shield door, specifically comprising: monitoring and obtaining the real-time monitoring value of the rail potential in the rail potential limiting device in the station and obtaining the status of the up-going shield door and the down-going shield door in the subway station; sending the status of the up-going shield door / down-going shield door in the station and the real-time monitoring value of the rail potential to a data monitoring center to generate a control command; sending the control command to the rail potential limiting device, and judging the starting strategy of the rail potential limiting device in combination with the rail potential monitoring value, so as to prohibit the rail potential limiting device from operating when the station shield door is closed and the rail potential level is less than a certain threshold. The present invention reduces the number of operations of the rail potential limiting device during train operation, realizes stray current protection, and reduces the corrosion effect of stray current on buried metal.

Description

Technical Field

[0001] The invention belongs to the field of rail transit operation safety, and in particular relates to a method for starting and controlling a rail potential limiting device taking into account the state of a shield door. Background Art

[0002] my country's urban rail transit power supply system generally uses 1500V DC power supply. In the DC power supply system, the running rail is usually used as a return rail. After the electric energy passes through the train, it returns the current to the negative pole of the traction station through the rail. In actual projects, the rail has longitudinal resistance, and the rail cannot be completely insulated from the ground, resulting in a potential between the rail and the earth, that is, the rail potential. In the actual subway system, a rail potential limiting device is usually installed between the rail and the grounding grid at the station. When the rail potential exceeds a certain threshold, the rail potential limiting device will start to directly ground the rail to prevent the rail potential at the station from being too high and endangering the safety of passengers getting on and off the subway.

[0003] Stray current refers to the current that leaks from the rails and does not flow along the prescribed path. Stray current will greatly accelerate the corrosion of metal structures such as the steel bars and buried pipelines of the subway civil engineering structure. The domestic protection principle for stray current is "blocking as the main method, drainage as the auxiliary method, combining prevention and drainage with enhanced monitoring". The main purpose of "blocking" is to fundamentally isolate and control all stray current leakage channels from the source and reduce the leakage of stray current. However, the current protection principle of "blocking as the main method" cannot prevent a large amount of stray current leaking from the rails from directly entering the ground after the rail potential limiting device is activated. However, the moment when the rail potential limiting device is activated due to the increase in rail potential usually occurs when the locomotive accelerates out of the station. At this time, the shield door has been closed, that is, the excessive rail potential will not endanger the personal safety of passengers. If the rail potential limiting device is frequently activated in this case, it will not only fail to protect the safety of passengers, but will greatly increase the leakage of stray current and cause serious corrosion of buried metal. Summary of the invention

[0004] In view of the above problems, the present invention provides a method for starting and controlling a rail potential limiting device taking into account the status of a shield door.

[0005] A method for starting and controlling a rail potential limiting device taking into account the state of a shield door of the present invention comprises the following steps:

[0006] Step A: Monitor and obtain the real-time monitoring value of the rail potential in the rail potential limiting device in the station.

[0007] Step A1: convert the rail potential monitoring value U in the rail potential limiting device in the station into a digital signal S1, and send it to the data monitoring center through the optical fiber network with a period of 1s.

[0008] Step B: Monitor and obtain the status of the up escalator screen doors and down escalator screen doors in the subway station.

[0009] Step B1: Represent the status of the up and down escalator screen doors in the station by the digital signal S2. The specific meaning of S2 is as follows:

[0010] S2 = 00 indicates that both the up and down escalator screen doors are in the closed state;

[0011] S2 = 01 indicates that the up escalator screen door is in the closed state and the down escalator screen door is in the open state;

[0012] S2 = 10 indicates that the up escalator screen door is in the open state and the down escalator screen door is in the closed state;

[0013] S2 = 11 indicates that both the up and down escalator screen doors are in the open state.

[0014] Step B2: Send the digital signal S2 to the data monitoring center through the optical fiber network at a period of 1 s.

[0015] Step C: Determine whether the rail potential limiting device operates according to the status of the up / down escalator screen doors in the station and the real-time monitoring value of the rail potential.

[0016] Step C1: Judge the relationship between the rail potential monitoring value U corresponding to S1 and the first-stage start threshold E1, the second-stage start threshold E2, and the third-stage start threshold E3 of the rail potential limiting device to determine the value of the control command S3. The specific judgment process is as follows:

[0017] If U < E1, then set the control command S3 = 0;

[0018] If E1 ≤ U < E2, and S2 = 01 or S2 = 10 or S2 = 11, then set the control command S3 = 0;

[0019] If E1 ≤ U < E2, and S2 = 00, then set the control command S3 = 1;

[0020] If E2 ≤ U < E3, and S2 = 01 or S2 = 10 or S2 = 11, then set the control command S3 = 0;

[0021] If E2 ≤ U < E3, and S2 = 00, then set the control command S3 = 1;

[0022] If U > E3, then set the control command S3 = 0.

[0023] Step C2: Send the control command S3 to the rail potential limiting device through the optical fiber network.

[0024] Step C3: The rail potential limiting device performs the following operations according to the control command S3 and the current rail potential monitoring value U:

[0025] If U < E1, the contactor of the rail potential limiting device is not closed and remains in the open state;

[0026] If E1 ≤ U < E2 and S3 = 0, the contactor of the rail potential limiting device is closed after a delay of t1 seconds, remains in the closed state within t2, and then returns to the open state;

[0027] If E1 ≤ U < E2 and S3 = 1, the contactor of the rail potential limiting device is not closed and remains in the open state;

[0028] If E2 ≤ U < E3 and S3 = 0, the contactor of the rail potential limiting device needs to be closed without delay and locked;

[0029] If E2 ≤ U < E3 and S3 = 1, the contactor of the rail potential limiting device is not closed and remains in the open state;

[0030] If U > E3, the thyristor of the rail potential limiting device conducts instantaneously and the contactor is locked.

[0031] The beneficial technical effects of the present invention are:

[0032] The present invention performs logical judgment by centrally collecting the monitoring values of the rail potential in the station and the opening and closing states of the platform screen doors in the up and down directions of the station, generates control commands and sends them to the rail potential limiting device to assist in judging the starting strategy of the rail potential limiting device, thereby achieving the purpose of reducing the action times of the rail limiting device, realizing stray current protection, and reducing the corrosion effect of stray current on buried metals. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 It is an explanatory diagram of the starting control process of a rail potential limiting device considering the state of the platform screen door.

[0034] Figure 2 It is a detailed flowchart of the starting control of a rail potential limiting device considering the state of the platform screen door. DETAILED DESCRIPTION OF THE INVENTION

[0035] The present invention will be further described in detail below with reference to the drawings and specific implementation methods.

[0036] The existing rail potential limiting device adopts a three - stage control strategy and does not consider the opening and closing states of the platform screen doors, resulting in frequent actions of the rail limiting device. The starting control method of the rail potential limiting device considering the state of the platform screen door of the present invention is as Figure 1As shown in the figure, the opening and closing state of the shield door is introduced as one of the indicators of the rail potential limiting device startup control strategy. By centrally collecting the station rail potential monitoring values ​​and the opening and closing state of the station's up and down shield doors, logical judgment is made, and a control command is generated and sent to the rail potential limiting device to jointly determine the rail potential limiting device startup strategy in combination with the real-time monitored rail potential. Considering the shield door, the number of actions of the rail potential limiting device can be significantly reduced, thereby avoiding a large amount of stray current directly entering the ground, avoiding a large amount of corrosion of buried metals, and ensuring the safety of water pipes, natural gas pipes, oil pipelines, etc. in urban infrastructure.

[0037] The specific process of the rail potential limiting device startup control method considering the shield door state of the present invention is as follows: Figure 2 As shown, the following steps are included:

[0038] Step A: Monitor and obtain the real-time monitoring value of the rail potential in the rail potential limiting device in the station.

[0039] Step A1: convert the rail potential monitoring value U in the rail potential limiting device in the station into a digital signal S1, and send it to the data monitoring center through the optical fiber network with a period of 1s.

[0040] Step B: Monitor and obtain the status of the up platform screen door and the down platform screen door in the subway station.

[0041] Step B1: The status of the up and down platform screen doors of the station is represented by a digital signal S2, and the specific meaning of S2 is as follows:

[0042] S2=00, indicating that both the uplink and downlink shield doors are in the closed state;

[0043] S2=01, indicating that the uplink shield door is in the closed state and the downlink shield door is in the open state;

[0044] S2=10, indicating that the uplink shield door is in the open state and the downlink shield door is in the closed state;

[0045] S2=11, indicating that both the uplink and downlink shielding doors are in the open state.

[0046] Step B2: Send the digital signal S2 to the data monitoring center via the optical fiber network with a period of 1 second.

[0047] Step C: Determine whether the rail potential limiting device is in operation according to the status of the uplink platform screen door / downlink platform screen door in the station and the real-time monitoring value of the rail potential.

[0048] Step C1: Determine the relationship between the rail potential monitoring value U corresponding to S1 and the first stage start threshold 90V, the second stage start threshold 150V, and the third stage start threshold 600V of the rail potential limiting device to determine the value of the control command S3. The specific judgment process is as follows:

[0049] If U<90V, set the control command S3=0;

[0050] If 90V≤U<150V, and S2=01 or S2=10 or S2=11, then set the control command S3=0;

[0051] If 90V≤U<150V, and S2=00, then set the control command S3=1;

[0052] If 150V≤U<600V, and S2=01 or S2=10 or S2=11, then set the control command S3=0;

[0053] If 150V≤U<600V, and S2=00, then set the control command S3=1;

[0054] If U>600V, the control command S3=0.

[0055] Step C2: Send the control command S3 to the rail potential limiting device through the optical fiber network.

[0056] Step C3: The rail potential limiting device performs the following operations according to the control command S3 and the current rail potential monitoring value U:

[0057] If U<90V, the contactor of the rail potential limiting device will not be closed and will remain in the disconnected state;

[0058] If 90V≤U<150V, and S3=0, the rail potential limiting device is closed after a delay of t1 seconds, and the closed state is saved during t2 time, and then the open state is restored;

[0059] If 90V≤U<150V, and S3=1, the contactor of the rail potential limiting device will not be closed and will remain in the open state;

[0060] If 150V≤U<600V, and S3=0, the contactor of the rail potential limiting device shall be closed and locked without delay;

[0061] If 150V≤U<600V, and S3=1, the contactor of the rail potential limiting device will not be closed and will remain in the open state;

[0062] If U>600V, the thyristor of the rail potential limiting device will be turned on instantaneously and the contactor will be locked.

Claims

1. A method for starting and controlling a rail potential limiting device taking into account the status of a shield door, characterized in that: Including the following steps: Step A: Monitor and obtain the real-time monitoring value of the rail potential in the rail potential limiting device in the station; Step A1: Convert the rail potential monitoring value U自带 in the rail potential limiting device in the station into a digital signal S1, and send it to the data monitoring center through the optical fiber network at a period of 1 s; Step B: Monitor and obtain the states of the up and down platform screen doors in the subway station; Step B1: Represent the states of the up and down platform screen doors in the station by the digital signal S2. The specific meanings of S2 are as follows: S2 = 00 means that both the up and down platform screen doors are in the closed state; S2 = 01 means that the up platform screen door is in the closed state and the down platform screen door is in the open state; S2 = 10 means that the up platform screen door is in the open state and the down platform screen door is in the closed state; S2 = 11 means that both the up and down platform screen doors are in the open state; Step B2: Send the digital signal S2 to the data monitoring center through the optical fiber network at a period of 1 s; Step C: Judge whether the rail potential limiting device operates according to the states of the up / down platform screen doors in the station and the real-time monitoring value of the rail potential; Step C1: Judge the relationship between the rail potential monitoring value U corresponding to S1 and the first-stage starting threshold E1, the second-stage starting threshold E2, and the third-stage starting threshold E3 of the rail potential limiting device to determine the value of the control command S3. The specific judgment process is as follows: If U < E1, then make the control command S3 = 0; If E1 ≤ U < E2, and S2 = 01 or S2 = 10 or S2 = 11, then make the control command S3 = 0; If E1 ≤ U < E2, and S2 = 00, then make the control command S3 = 1; If E2 ≤ U < E3, and S2 = 01 or S2 = 10 or S2 = 11, then make the control command S3 = 0; If E2 ≤ U < E3, and S2 = 00, then make the control command S3 = 1; If U > E3, then make the control command S3 = 0; Step C2: Send the control command S3 to the rail potential limiting device through the optical fiber network; Step C3: The rail potential limiting device performs the following operations according to the control command S3 and the current rail potential monitoring value U: If U < E1, then make the contactor of the rail potential limiting device not close and remain in the open state; If E1 ≤ U < E2, and S3 = 0, then make the contactor of the rail potential limiting device close after a delay of t1 seconds, keep the closing state within t2, and then return to the open state; If E1 ≤ U < E2, and S3 = 1, then make the contactor of the rail potential limiting device not close and remain in the open state; If E2 ≤ U < E3, and S3 = 0, then the contactor of the rail potential limiting device needs to close and lock without delay; If E2 ≤ U < E3, and S3 = 1, then make the contactor of the rail potential limiting device not close and remain in the open state; If U > E3, make the thyristor of the rail potential limiting device conduct instantaneously and the contactor lock.

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