Maintenance Safety Protection Method and Device for Charging Rails of Energy Storage Trams

Abstract

The present application discloses a maintenance safety protection method for the charging rail of an energy storage tram, which is applicable to the maintenance of the charging rail in the depot. The method includes moving the roof charging rail to the recovery position after the vehicle enters the depot and the energy storage unit is completely discharged. When the roof charging rail is moved to the recovery position, an additional negative branch is formed to connect the roof charging rail to the rail (negative pole). The present invention also discloses a maintenance safety protection device for the charging rail of a tram. By forming an additional negative branch when the roof charging rail is moved to the recovery position and connecting the roof charging rail to the rail (negative pole), the method and device of the present invention can directly connect the charging rail to the rail during maintenance, avoiding mischarging caused by the inability to identify the track-ground transition impedance or the internal resistance of the energy storage element, and eliminating potential safety hazards.

Description

Technical Field

[0001] This application relates to the technical field of maintenance safety protection for charging rails of energy storage tramcars, and more specifically, to a maintenance safety protection method and device for charging rails of energy storage tramcars. Background Art

[0002] In the depot, in order to meet the boarding and maintenance operations of vehicle maintenance personnel, the on-vehicle energy storage unit generally needs to be fully discharged, and then the roof charging rail is removed. After the maintenance is completed, the charging rail is returned to its original position for charging. The circuit of the charging system usually connects the positive electrode to the roof charging rail and the negative electrode to the rail to charge the on-vehicle energy storage unit.

[0003] During the boarding maintenance operation after full discharge in the depot, the current conventional method is that the roof charging rail connected to the positive electrode is directly connected to the ground grid after being recovered, that is, the positive electrode of the charging rail is connected to the ground grid, disconnecting the charging system from the on-vehicle energy storage unit, so that the charging system does not affect the on-vehicle energy storage unit and prevent the voltage difference from harming the maintenance personnel.

[0004] However, since the converter of the charging system in the depot is set to start with zero voltage and constant current charging, the constant current charging system must be set to charge the energy storage unit with zero voltage on the outlet side. Currently, there is a situation where it is misidentified as the internal resistance load of the energy storage unit, resulting in the startup of the charging system. That is, when the positive electrode of the moving charging rail is grounded, the charging startup condition still exists, which may pose a risk of personal injury to the maintenance personnel of the charging rail. Summary of the Invention

[0005] In view of the problems or improvement requirements existing in the prior art, the present invention provides a maintenance safety protection method and device for charging rails of tramcars, which can completely overcome the situation of mis-startup of the charging system.

[0006] According to one aspect of the present invention, a maintenance safety protection method for charging rails of tramcars is provided, which is applicable to the maintenance of charging rails in the depot. The method is characterized by including:

[0007] When the roof charging rail is moved to the recovery position, an additional negative branch is formed to connect the roof charging rail to the rail.

[0008] As a further improvement of the present invention, the formation of the negative branch is specifically as follows: a negative connection point is set at the recovery position of the roof charging rail, and the negative connection point is connected to the rail through a cable. When the roof charging rail moves to the recovery position, it is conducted with the negative connection point.

[0009] As a further improvement of the present invention, when the roof charging rail is moved to the recovery position, a grounding branch is formed at the same time, enabling the roof charging rail to be conducted with the ground grid.

[0010] As a further improvement of the present invention, the formation of the grounding branch is specifically achieved by setting a grounding connection point. When the roof charging rail moves to the recovery position, it can be conducted with the grounding connection point and connected to the ground grid to form a grounding branch.

[0011] As a further improvement of the present invention, a current amplifier is installed on the negative branch for collecting the current on the negative branch.

[0012] As a further improvement of the present invention, the collected current on the negative branch can be used for display output;

[0013] and / or input to an overcurrent alarm element to output an alarm signal when the threshold is exceeded;

[0014] and / or input to a relay for controlling the converter to trip, serving as a signal for controlling the on / off of the converter to further control mischarging.

[0015] According to another aspect of the present invention, a maintenance safety protection device for a tram charging rail is provided, which is applicable to the maintenance of the charging rail in the depot. It is characterized by including:

[0016] A device body is arranged at the position of the removable charging rail series. A connection point communicating with the rail is arranged inside the device body; and a conducting connection point is arranged at the recovery position of the roof charging rail. It is connected to one end of a cable, and the other end of this cable is connected to the body connection point. When the roof charging rail moves to the recovery position, it is connected to the conducting connection point, and then conducts with the rail through the body connection point to form a negative branch.

[0017] As a further improvement of the present invention, the body connection point further includes a grounding connection point conducting with the ground grid. When the roof charging rail moves to the recovery position, it can conduct with the ground grid through the body connection point to form a grounding branch as needed.

[0018] As a further improvement of the present invention, a current amplifier is installed on the negative branch inside the device body for collecting the current on the negative branch.

[0019] As a further improvement of the present invention, a display output unit is arranged on the device body, and the collected current on the negative branch can be used for display output;

[0020] and / or an overcurrent alarm element is arranged on the device body, and an alarm signal is output when the collected current on the negative branch exceeds the threshold;

[0021] A relay for controlling the converter to trip is provided on the device body, and the current collected on the negative branch can be input into the relay as a signal for controlling the on / off of the converter to further control mischarging.

[0022] Generally speaking, compared with the prior art, the above technical solution conceived by the present invention can achieve the following beneficial effects:

[0023] (1) The inspection safety protection method and device for the charging rail of a tram provided by the present invention are applicable to the inspection of the charging rail in the depot. By forming an additional negative branch when the roof charging rail is moved to the recovery position, the roof charging rail is connected to the steel rail, so that the charging rail can be directly connected to the steel rail during the inspection, and the mischarging caused by the inability to identify whether it is a ground grid transition load or a storage element resistance load can be avoided, eliminating potential safety hazards.

[0024] (2) The inspection safety protection method and device for the charging rail of a tram provided by the present invention also set a current acquisition unit on the negative branch. By collecting and identifying the magnitude of the current on the negative branch, timely identification and alarm processing are carried out, and further, the converter is controlled to trip by a relay to cut off mischarging, avoiding potential safety hazards caused by mischarging.

[0025] (3) The inspection safety protection method and device for the charging rail of a tram provided by the present invention can also set a grounding branch, that is, while setting the negative branch to ensure that the roof charging rail is connected to the steel rail when it is moved to the recovery position, it can be conducted to the ground grid to ensure personal safety. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following will briefly introduce the drawings required in the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0027] Figure 1 It is a schematic flow chart of an inspection safety protection method for a charging rail of a tram provided by an embodiment of the present application;

[0028] Figure 2 It is a schematic structural diagram of an inspection safety protection device for a charging rail of a tram provided by an embodiment of the present application. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0029] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention. In addition, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0030] The terms "first", "second", "third", etc. in the specification, claims and the above-mentioned drawings of the present application are used to distinguish different objects, rather than to describe a specific order. In addition, the terms "comprising" and "having" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product or device that includes a series of steps or units is not limited to the listed steps or units, but optionally further includes steps or units not listed, or optionally further includes other steps or units inherent to these processes, methods, products or devices.

[0031] In order to meet the boarding and maintenance operations of vehicle maintenance personnel in the depot of the energy storage tram, the on-vehicle energy storage unit is completely discharged, and the charging rail on the roof is removed. In the normal mode, at this time, after the charging rail on the roof is recycled, it will be directly connected to the ground grid, and the positive pole of the charging rail is connected to the ground grid. In this working condition, the charging system often starts to charge, resulting in a possible voltage difference in the working environment, posing a greater risk to the safety of maintenance personnel.

[0032] The inventors of the present application have found through research that after the charging rail on the roof is recycled and directly connected to the ground grid and connected to it, there is usually a negative ground transition resistance. Especially because the ground grid conduction is usually carried out in a way that is connected to the steel bars in the concrete, and the presence of media such as concrete will all lead to the existence of the transition resistance and will not be a true ground connection. In addition, due to the different charging methods in the depot and on the main line, the starting voltage of the charging system on the main line is not allowed to be lower than the minimum output voltage of the energy storage unit (generally, for example, 400V), which can effectively distinguish the difference between a DC side short circuit and the internal resistance of the energy storage unit. That is, when there is a DC side short circuit, since there is no voltage at the outlet side itself, the charging condition is not met and charging cannot be carried out. In the depot, the converter needs to be set to start with zero voltage and charge with a constant current source, that is, the constant current source charging system must be set to charge the energy storage unit with zero voltage at the outlet side. In this working condition, the existence of the negative ground transition resistance makes it difficult for the charging system to effectively distinguish the negative ground transition resistance and the internal resistance of the energy storage medium itself, and it is impossible to normally identify a short circuit and the load of the energy storage unit. That is, under the condition that the positive pole of the mobile charging rail is grounded, the charging system still has the condition to start charging, and it is possible that the charging system will start mistakenly, which may cause a risk of personal injury to the maintenance personnel of the charging rail.

[0033] Such as Figure 1As shown in the figure, a maintenance safety protection method for a charging rail of a tram proposed in this solution proposes a complete technical solution by discovering the essence of the above problems. Specifically, the method of this solution includes: S100 First, after the vehicle enters the yard section and the energy storage unit is completely discharged, the roof charging rail is moved to the recovery position; S200 Second, at the recovery position, the charging rail is directly connected to the return rail to form a negative branch. At this time, the positive charging rail is directly connected to the negative rail, so there will be no pressure difference between the charging rail and the rail, and the charging system will not recognize the existence of an energy storage medium load and will not start charging.

[0034] Specifically, in a preferred embodiment, a negative connection point is provided at the recovery position of the roof charging rail. The negative connection point is connected to the rail through a cable, and the roof charging rail is conducted with the negative connection point when it is moved to the recovery position.

[0035] For example, a connecting copper bar is provided on one side of the moving charging rail and moves synchronously with the charging rail as the negative connection point. Of course, other methods can also be used to set the negative connection point, which is not limited in this solution. Correspondingly, a fixed copper bar matching the connecting copper bar is provided at the recovery position of the charging rail as the matching connection point. It is preferably provided on the side wall at the recovery position of the charging rail and is insulated and fixed to the side wall. Of course, the fixed copper bar in this solution can be in other connection forms, not limited to copper bars, as long as it can be matched and connected with the connecting copper bar on the moving charging rail.

[0036] The above matching connection point is conducted with the rail as the negative pole. Preferably, it is directly connected through a cable or other wire, or can also be conducted through other means. For example, it can be connected to an intermediate control box through a cable or other wire, and the control box is then connected and conducted with the rail through a cable or other wire. In this way, an additional negative branch is formed when the roof charging rail is moved away to the recovery position, so that the roof charging rail is connected to the rail.

[0037] Through the above method, a negative branch connecting the charging rail and the rail is formed. In this working condition, on the one hand, it will not be mischarged because of the existence of a negative ground transition resistance and misidentifying it as an energy storage medium load itself. On the other hand, the current on this branch can be monitored, that is, the current magnitude of the direct connection branch between the charging rail and the rail is monitored to judge whether there is mis-power transmission. Under normal circumstances, the branch current is 0. If there is a fault, the current of this negative branch is the rated charging current, so it can be quickly judged as a fault.

[0038] The method of this solution is applicable to the maintenance of the charging rail within the yard section. When the charging rail on the roof is moved to the recovery position, an additional negative branch is formed, connecting the charging rail on the roof to the rail, so that the charging rail is directly connected to the rail during maintenance, preventing mischarging caused by the inability to distinguish between the ground grid transition load and the energy storage element resistance load and eliminating potential safety hazards.

[0039] In a preferred embodiment, when the charging rail on the roof is moved to the recovery position, in addition to forming a negative branch, a grounding branch can also be formed simultaneously to connect the charging rail on the roof to the ground grid. That is, in this solution, the charging rail on the roof is also connected to the ground grid. Specifically, in the solution of this grounding branch, a grounding connection point is preferably set. When the charging rail on the roof moves to the recovery position, it can be connected to the grounding connection point and then connected to the ground grid to form a grounding branch. For example, a grounding connection point can be set beside the above-mentioned matching connection point. This grounding connection point is directly grounded through a cable or other wire, and the fixed connection point set on the charging rail is used to match with this grounding connection point, so that when the charging rail on the roof is moved to the recovery position, it can also be connected to the ground grid to achieve grounding. In another preferred solution, a part of the cable can be shared with the negative branch, that is, the grounding connection point can be set in the intermediate control box. One end of the cable or other wire is connected to the connection point in the intermediate control box, and the other end is connected to the ground to achieve connection to the ground grid.

[0040] Preferably, the setting of the grounding branch is an optional means, that is, the grounding branch is not necessarily required, and the conduction of the grounding branch can be automatic or set to manual conduction, that is, manually closing the grounding branch. In this way, when maintenance of the charging rail body and its vicinity is required, the grounding branch can be selected to be closed, so that the grounding branch is also conducted, and then the charging rail is connected to the ground grid to meet the requirement of equipotential and prevent electric shock to people.

[0041] By simultaneously setting the ground grid conduction, a complementary maintenance safety solution can be formed with the negative branch, achieving double "grounding", which is more conducive to avoiding safety risks.

[0042] In a preferred embodiment, a current amplifier is installed on the negative branch to collect the current on the negative branch. The presence and magnitude of the collected current can be used to monitor whether the current on this branch is normal or in a fault situation. For example, under normal circumstances, the branch current is 0. If there is a fault situation, the current on the negative branch is the rated charging current, so that a fault can be quickly determined.

[0043] Preferably, the current collected on the negative electrode branch can be displayed through a display output device for real-time transmission to monitoring personnel for monitoring. An overcurrent alarm element can also be set. When the current exceeds a preset current threshold, an alarm signal can be emitted to determine whether there is a fault. The current can also be input into a relay that controls the tripping of the converter as a signal for controlling the on / off of the converter. In this way, when the current exceeds the threshold, the converter can be cut off to further control mischarging.

[0044] Based on the limitations of the actual operating conditions, the constant current source charging system cannot normally identify short circuits and energy storage unit loads. Special technical means are adopted for fault identification, that is, in the recovery state, the presence or absence or magnitude of the current in the branch directly connecting the charging rail and the steel rail is monitored to determine whether there is mis-power transmission. Since the constant current charging current is relatively large (400 A or above), the moving charging rail in the recovery state is grounded (the ground here is the ground grid). Due to the existence of a transition (insulation) resistance between the negative electrode and the ground grid, a voltage difference between the negative electrode and the ground may be generated, which may pose a personal hazard. The moving charging rail is directly connected to the negative electrode (steel rail), and the voltage difference between the steel rail and the ground is relatively small, thus overcoming the above technical problems.

[0045] As Figure 2 shown, the present invention also proposes a maintenance safety protection device for a charging rail of a tram, which is applicable to the maintenance of the charging rail in the depot. The safety protection device of this solution includes a device body and a conduction connection point communicated with the device body.

[0046] Specifically, the device body is arranged at the position of the removable charging rail row, for example, fixed on the side wall, as a carrier for controlling or outputting relevant information. The device body can be a box, a shell or other corresponding structures, which can be specifically selected according to actual needs.

[0047] In the device body of this solution, a body connection point communicated with the steel rail is arranged. The body connection point is preferably a connecting copper bar and can also be other connection structures. The connection point is used to connect with the steel rail through a cable or other wires.

[0048] The device of this solution also includes a conduction connection point, which is arranged at the recovery position of the roof charging rail and matches the charging rail connection point. On the one hand, it is used to connect with the charging rail, that is, it can be conducted with the charging rail when the charging rail is in the recovery position. On the other hand, it is connected to the access body connection point through a cable or other wires. In this way, when the roof charging rail moves to the recovery position, the charging rail can be connected to the steel rail through the conduction connection point, the cable or wire, and the body connection point to form a negative electrode branch.

[0049] Preferably, a connecting copper bar is arranged on one side of the mobile charging rail and moves synchronously with the charging rail. The conduction connection point is matched with the connecting copper bar, so that when the charging rail is in the retracted position, the connecting copper bar is conducted with the conduction connection point. For example, the conduction connection point can be arranged on the side wall at the retracted position of the charging rail and is fixedly insulated from the side wall. Of course, it can also be arranged at other suitable positions.

[0050] In a preferred embodiment, the body connection point inside the device body further includes a grounding connection point that is conducted with the ground grid. When the roof charging rail moves to the retracted position, it can be conducted with the ground grid through the body connection point to form a grounding branch.

[0051] By setting the ground grid conduction at the same time, a maintenance safety plan that complements the negative branch can be formed to perform double "grounding", which is more conducive to avoiding safety risks.

[0052] In a preferred embodiment, a current amplifier is installed on the negative branch inside the device body to collect the current on the negative branch. The presence and magnitude of the collected current can be used to monitor whether the current on this branch is a normal current or a current in a fault situation. For example, under normal circumstances, the branch current is 0. If there is a fault situation, the negative branch current is the rated charging current, so that a fault can be quickly judged.

[0053] Preferably, a display device is also arranged on the device body, such as a display screen or other output devices. The current on the collected negative branch can be displayed through the display device or output through the output device for real-time transmission to the monitoring personnel for monitoring.

[0054] Preferably, an overcurrent alarm element is also arranged on the negative branch inside the device body. When the current flows through the overcurrent alarm element and exceeds the preset current threshold, an alarm signal can be issued, which is used as a basis for judging whether there is a fault.

[0055] In a preferred embodiment, a latching control circuit is also arranged inside the device body. A relay is arranged on it. The circuit of the above-mentioned negative branch is collected through this relay. Under the set preconditions, the converter is controlled to trip, which is used as a signal to control the on and off of the converter. In this way, when the current exceeds the threshold, the converter can be cut off to further control mischarging.

[0056] The above are only exemplary embodiments of the present disclosure, and the scope of the present disclosure cannot be limited thereby. That is, any equivalent changes and modifications made in accordance with the teachings of the present disclosure still fall within the scope covered by the present disclosure. Those skilled in the art will readily conceive of other embodiments of the present disclosure after considering the specification and practicing the disclosure herein. This application is intended to cover any variations, uses, or adaptations of the present disclosure that follow the general principles of the present disclosure and include known common general knowledge or conventional technical means in the technical field not described in the present disclosure. The specification and embodiments are only regarded as exemplary, and the scope and spirit of the present disclosure are defined by the claims.

[0057] The technical features of the above embodiments can be combined arbitrarily. For the sake of brevity of description, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, it should be considered that the scope described in this specification is covered.

[0058] Those skilled in the art can easily understand that the above are only preferred embodiments of the present invention, and are not intended to limit the present invention. Any modifications, equivalent replacements, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A maintenance safety protection method for the charging rail of an energy storage tram, applicable to the maintenance of the charging rail in the depot, characterized in that, Including: After the vehicle enters the depot and the energy storage unit is completely discharged, when the roof charging rail is moved to the recovery position, an additional negative branch is formed to connect the roof charging rail to the rail; Specifically, the formation of the negative branch is to set a negative connection point at the recovery position of the roof charging rail. The negative connection point is connected to the rail through a cable, and the roof charging rail is conducted with the negative connection point when it is moved to the recovery position.

2. The maintenance safety protection method for the charging rail of an energy storage tram according to claim 1, wherein, When the roof charging rail is moved away to the recovery position, a grounding branch can be formed to connect the roof charging rail to the ground grid.

3. The maintenance safety protection method for the charging rail of an energy storage tram according to claim 2, wherein, Specifically, the formation of the grounding branch is to set a grounding connection point. When the roof charging rail is moved to the recovery position, it is conducted with the grounding connection point and can be connected to the ground grid to form a grounding branch.

4. The maintenance safety protection method for the charging rail of a tram according to any one of claims 1 - 3, wherein, An current amplifier is installed on the negative branch for collecting the current on the negative branch.

5. The maintenance safety protection method for the charging rail of a tram according to claim 4, wherein, The collected current on the negative branch can be displayed and output through a transmitter; And / or input to an overcurrent alarm component to output an alarm signal when exceeding the threshold; And / or input to a relay for controlling the converter to trip, serving as a signal for controlling the on / off of the converter to further control mischarging.

6. A maintenance safety protection device for the charging rail of a tram, applicable to the maintenance of the charging rail in the depot, characterized in that, Including: The device body is arranged at the position of the removable charging rail. A body connection point connected to the rail is arranged inside the device body; And a conducting connection point is arranged at the recovery position of the roof charging rail. One end of a cable is connected to it, and the other end of the cable is connected to the body connection point. When the roof charging rail is moved to the recovery position, it is connected to the conducting connection point, and then conducted with the rail through the body connection point to form a negative branch.

7. The maintenance safety protection device for the charging rail of a tram according to claim 6, wherein, The body connection point further includes a grounding connection point conducted with the ground grid. When the roof charging rail is moved to the recovery position, it can be conducted with the ground grid through the body connection point to form a grounding branch.

8. The maintenance safety protection device for the charging rail of a tram according to claim 6 or 7, wherein, An current amplifier is installed on the negative branch inside the device body for collecting the current on the negative branch.

9. The maintenance safety protection device for the charging rail of a tram according to claim 8, wherein, A display output unit is arranged on the device body. The collected current on the negative branch can be used for display output; And / or an overcurrent alarm component is arranged on the device body to output an alarm signal when the collected current on the negative branch exceeds the threshold; And / or a relay for controlling the converter to trip is arranged on the device body. The collected current on the negative branch can be input to the relay as a signal for controlling the on / off of the converter to further control mischarging.

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