CN118444204B - Contact net grounding equipment, loop continuity monitoring device and method - Google Patents

Abstract

The contact network grounding equipment, loop continuity monitoring device and method provided in the present application relate to the field of contact network technology. In the present application, the contact network grounding equipment includes a contact network grounding device and a loop continuity monitoring device, the contact network grounding device includes a contact network line, a grounding knife switch and a return rail line, the contact network line includes a first contact network line and a second contact network line, constituting a first test loop, and the return rail line includes a first return rail line and a second return rail line, constituting a second test loop. The loop continuity monitoring device includes a first monitoring module and a second monitoring module, which are used to monitor the loop continuity of the first test loop and the second test loop. Based on the above content, the problem of low reliability in monitoring the contact network grounding device in the prior art can be improved.

Description

Contact network grounding equipment, loop continuity monitoring device and method

Technical Field

The present application relates to the field of contact network technology, and in particular to a contact network grounding device, a loop continuity monitoring device and a method.

Background Art

During the maintenance of overhead contact networks (such as subway overhead contact networks, etc.), temporary grounding wires need to be installed in the operation area. The traditional method of hanging grounding wires is that before the maintenance work, the staff will bring grounding wires and electric testers to the site, manually test the electricity, hang the grounding wires, and remove the grounding wires after the maintenance is completed. The traditional operation method has the risk of hanging grounding wires with power on, and there are hidden dangers of power transmission with grounding wires. It is completely dependent on manual labor, with heavy tasks, long time, low efficiency, and squeezed normal maintenance operation time.

At present, the contact network grounding device has been widely used in the contact network (contact rail) of urban rail transit main line or vehicle depot, parking lot, etc., which can reduce operation time, improve maintenance efficiency, ensure the personal safety of workers, and achieve the purpose of safe, reliable and economical operation. The application of the contact network grounding device can prevent the contact network (rail) from being energized and hanging the ground wire, and transmitting power with the ground wire, so as to ensure safety with technology and equipment, make up for the shortcomings of traditional safety with system, and greatly reduce the proportion of hanging/removing the ground wire while ensuring safety, release more actual maintenance time, and improve maintenance efficiency.

Based on this, in order to ensure that the contact network grounding device can be effectively grounded, it is necessary to monitor the contact network grounding device. However, the inventors have found through research that there is a problem that the reliability of monitoring the contact network grounding device is relatively low.

Summary of the invention

In view of this, the purpose of the present application is to provide a contact network grounding device, a loop continuity monitoring device and a method to improve the problem of relatively low reliability in monitoring the contact network grounding device in the prior art.

To achieve the above purpose, this application adopts the following technical solutions:

A contact network grounding device, comprising a contact network grounding device and a loop continuity monitoring device, wherein the contact network grounding device comprises a contact network line, a grounding knife switch and a return rail line, wherein the contact network line, the grounding knife switch and the return rail line are connected in series between the contact network and the return rail, and are used to perform grounding control on the contact network and the return rail;

The contact network line includes a first contact network line and a second contact network line, and/or the return rail line includes a first return rail line and a second return rail line;

When the overhead contact network line includes the first overhead contact network line and the second overhead contact network line, the first overhead contact network line and the second overhead contact network line are connected in parallel between the first end of the grounding knife switch and the overhead contact network to form a first test loop including the first overhead contact network line, the second overhead contact network line and the overhead contact network;

When the return rail circuit includes the first return rail circuit and the second return rail circuit, the first return rail circuit and the second return rail circuit are connected in parallel between the second end of the grounding knife switch and the return rail to form a second test loop including the first return rail circuit, the second return rail circuit and the return rail;

The loop continuity monitoring device includes a first monitoring module and/or a second monitoring module. The first monitoring module is arranged in conjunction with the first test loop, and the first monitoring module is used to monitor the loop continuity of the first test loop; the second monitoring module is arranged in conjunction with the second test loop, and the second monitoring module is used to monitor the loop continuity of the second test loop.

In a preferred option of the present application, in the above-mentioned overhead line grounding device, the loop continuity monitoring device further includes a processor, and the first monitoring module includes a first excitation current transformer and a first monitoring current transformer, and the first excitation current transformer and the first monitoring current transformer are respectively arranged in the first test loop;

wherein, after the processor controls the external power supply to provide the first excitation current transformer with the first current, if the first monitoring current transformer outputs the second current, it is determined that the first test loop is in a closed connection state; if the first monitoring current transformer does not output the second current, it is determined that the first test loop is not in a closed connection state;

Furthermore, the first excitation current transformer generates a first induced current in the first test loop in a closed connection state in response to the first current, and the first monitoring current transformer outputs the second current in response to the first induced current.

In a preferred option of the present application, in the above-mentioned overhead line grounding device, the loop continuity monitoring device further includes a processor, and the second monitoring module includes a second excitation current transformer and a second monitoring current transformer, and the second excitation current transformer and the second monitoring current transformer are respectively arranged in the second test loop;

wherein, after the processor controls the external power supply to provide the third current to the second excitation current transformer, if the second monitoring current transformer outputs the fourth current, it is determined that the second test loop is in a closed connection state; if the second monitoring current transformer does not output the fourth current, it is determined that the second test loop is not in a closed connection state;

Furthermore, the second excitation current transformer generates a second induced current in the second test loop in a closed connection state in response to the third current, and the second monitoring current transformer outputs the fourth current in response to the second induced current.

In a preferred option of the present application, in the above-mentioned contact network grounding equipment, the loop continuity monitoring device also includes a third monitoring module, wherein the third monitoring module is arranged in cooperation with the grounding switch to monitor the loop continuity of the grounding switch.

In a preferred embodiment of the present application, in the above-mentioned overhead line grounding device, the loop continuity monitoring device further includes a processor, and the third monitoring module includes:

A first high voltage withstand unit, wherein a first end of the first high voltage withstand unit is connected to a first end of the grounding switch;

A current limiting resistor, wherein a first end of the current limiting resistor is connected to a second end of the first high withstand voltage unit;

A test signal control unit, wherein a first end of the test signal control unit is connected to a second end of the current limiting resistor, and a second end of the test signal control unit is connected to the processor;

A signal generator, wherein a first end of the signal generator is connected to a third end of the test signal control unit, and a second end of the signal generator is connected to the processor;

a current measuring unit, wherein a first terminal of the current measuring unit is connected to a third terminal of the signal generator, and a second terminal of the current measuring unit is connected to the processor;

A second high-voltage withstand unit, wherein a first end of the second high-voltage withstand unit is connected to a second end of the grounding switch, and a second end of the second high-voltage withstand unit is connected to a third end of the current measuring unit;

A voltage measuring unit, wherein a first end of the voltage measuring unit is connected to a second end of the first high withstand voltage unit, a second end of the voltage measuring unit is connected to a second end of the second high withstand voltage unit, and a third end of the voltage measuring unit is connected to the processor.

In a preferred embodiment of the present application, in the above-mentioned contact network grounding device, the third monitoring module further includes:

An induced voltage prevention unit, wherein the first end of the induced voltage prevention unit is connected to the second end of the first high voltage withstand unit, the second end of the induced voltage prevention unit is connected to the second end of the second high voltage withstand unit, and the induced voltage prevention unit is used to perform high voltage protection on the third monitoring module.

The present application also provides a loop continuity monitoring device for monitoring a contact network grounding device, wherein the contact network grounding device comprises a contact network line, a grounding switch and a return rail line, wherein the contact network line comprises a first contact network line and a second contact network line, and/or the return rail line comprises a first return rail line and a second return rail line;

When the overhead contact network line includes the first overhead contact network line and the second overhead contact network line, the first overhead contact network line and the second overhead contact network line are connected in parallel between the first end of the grounding knife switch and the overhead contact network to form a first test loop including the first overhead contact network line, the second overhead contact network line and the overhead contact network;

When the return rail circuit includes the first return rail circuit and the second return rail circuit, the first return rail circuit and the second return rail circuit are connected in parallel between the second end of the grounding knife switch and the return rail to form a second test loop including the first return rail circuit, the second return rail circuit and the return rail;

Among them, the loop continuity monitoring device includes a first monitoring module and/or a second monitoring module, the first monitoring module is arranged in conjunction with the first test loop, and the first monitoring module is used to monitor the loop continuity of the first test loop; the second monitoring module is arranged in conjunction with the second test loop, and the second monitoring module is used to monitor the loop continuity of the second test loop.

The present application also provides a loop continuity monitoring method, which is applied to a loop continuity monitoring device to monitor a contact network grounding device;

The contact network grounding device comprises a contact network line, a grounding switch and a return rail line, the contact network line comprises a first contact network line and a second contact network line, and/or the return rail line comprises a first return rail line and a second return rail line;

When the overhead contact network line includes the first overhead contact network line and the second overhead contact network line, the first overhead contact network line and the second overhead contact network line are connected in parallel between the first end of the earthing knife switch and the overhead contact network to form a first test loop including the first overhead contact network line, the second overhead contact network line and the overhead contact network; when the return rail line includes the first return rail line and the second return rail line, the first return rail line and the second return rail line are connected in parallel between the second end of the earthing knife switch and the return rail to form a second test loop including the first return rail line, the second return rail line and the return rail;

Wherein, the loop continuity monitoring device includes a first monitoring module and/or a second monitoring module, the first monitoring module is arranged in cooperation with the first test loop, and the second monitoring module is arranged in cooperation with the second test loop;

Wherein, the loop continuity monitoring method comprises:

Using the first monitoring module, monitoring the loop continuity of the first test loop to obtain a corresponding first test loop continuity monitoring result; and/or

The loop continuity of the second test loop is monitored by utilizing the second monitoring module to obtain a corresponding second test loop continuity monitoring result.

In a preferred selection of the present application, in the above-mentioned loop continuity monitoring method, the loop continuity monitoring device also includes a processor, and the first monitoring module includes a first excitation current transformer and a first monitoring current transformer, the first excitation current transformer and the first monitoring current transformer are respectively arranged in the first test loop, the first excitation current transformer generates a first induced current in the first test loop in response to the input first current in a closed connection state, and the first monitoring current transformer outputs a second current in response to the first induced current; the second monitoring module includes a second excitation current transformer and a second monitoring current transformer, the second excitation current transformer and the second monitoring current transformer are respectively arranged in the second test loop, the second excitation current transformer generates a second induced current in the second test loop in response to the input third current in a closed connection state, and the second monitoring current transformer outputs a fourth current in response to the second induced current;

The step of using the first monitoring module to monitor the loop continuity of the first test loop to obtain the corresponding first test loop continuity monitoring result includes:

The processor controls the external power supply to provide the first excitation current transformer with a first current, and monitors whether the first monitoring current transformer outputs a second current;

When the processor detects that the first monitoring current transformer outputs the second current, the processor outputs a first test loop continuity monitoring result for indicating that the first test loop is in a closed connection state; when the processor detects that the first monitoring current transformer does not output the second current, the processor outputs a first test loop continuity monitoring result for indicating that the first test loop is not in a closed connection state;

The step of using the second monitoring module to monitor the loop continuity of the second test loop to obtain the corresponding second test loop continuity monitoring result includes:

The processor controls the external power supply to provide the third current to the second excitation current transformer, and monitors whether the second monitoring current transformer outputs the fourth current;

When the processor detects that the second monitoring current transformer outputs the fourth current, the processor outputs a second test loop continuity monitoring result for characterizing that the second test loop is in a closed connection state. When the processor detects that the second monitoring current transformer does not output the fourth current, the processor outputs a second test loop continuity monitoring result for characterizing that the second test loop is not in a closed connection state.

In a preferred option of the present application, in the above loop continuity monitoring method, the loop continuity monitoring device further includes a processor and a third monitoring module;

The third monitoring module includes a first high withstand voltage unit, a current limiting resistor, a test signal control unit, a signal generator, a current measuring unit, a second high withstand voltage unit and a voltage measuring unit, wherein the first end of the first high withstand voltage unit is connected to the first end of the grounding switch, the first end of the current limiting resistor is connected to the second end of the first high withstand voltage unit, the first end of the test signal control unit is connected to the second end of the current limiting resistor, the second end of the test signal control unit is connected to the processor, the first end of the signal generator is connected to the third end of the test signal control unit, the second end of the signal generator is connected to the processor, the first end of the current measuring unit is connected to the third end of the signal generator, the second end of the current measuring unit is connected to the processor, the first end of the second high withstand voltage unit is connected to the second end of the grounding switch, the second end of the second high withstand voltage unit is connected to the third end of the current measuring unit, the first end of the voltage measuring unit is connected to the second end of the first high withstand voltage unit, the second end of the voltage measuring unit is connected to the second end of the second high withstand voltage unit, and the third end of the voltage measuring unit is connected to the processor;

Wherein, the loop continuity monitoring method further includes:

After the grounding switch is closed, the first high-voltage withstand unit is closed, and the second high-voltage withstand unit is closed, the processor controls the voltage measuring unit to measure the voltage between the second end of the first high-voltage withstand unit and the second end of the second high-voltage withstand unit to obtain a first voltage;

After obtaining the first voltage, the processor controls the signal generator to output a test current through the test signal control unit and the current limiting resistor, controls the voltage measuring unit to measure the voltage between the second end of the first high withstand voltage unit and the second end of the second high withstand voltage unit to obtain a second voltage, and controls the current measuring unit to measure the test current;

The processor determines the loop resistance of the grounding switch based on the first voltage, the second voltage and the test current, and determines the third loop continuity monitoring result corresponding to the grounding switch based on the loop resistance.

In the overhead contact network grounding equipment, loop continuity monitoring device and method provided in the present application, the loop continuity monitoring device is used to monitor the overhead contact network grounding device, the overhead contact network grounding device includes an overhead contact network line, an earthing knife switch and a return rail line, the overhead contact network line includes a first overhead contact network line and a second overhead contact network line, forming a first test loop, and the return rail line includes a first return rail line and a second return rail line, forming a second test loop. The loop continuity monitoring device includes a first monitoring module and a second monitoring module, which are used to monitor the loop continuity of the first test loop and the second test loop respectively. Based on the above content, since the contact network line includes the first contact network line and the second contact network line which can form a first test loop with the contact network, the loop continuity monitoring of the first test loop can be performed separately. Similarly, since the return rail line includes the first return rail line and the second return rail line which can form a second test loop with the return rail, the loop continuity monitoring of the second test loop can also be performed separately. In this way, loop continuity monitoring with a smaller granularity can be achieved, thereby improving the reliability of loop continuity monitoring and facilitating abnormality positioning (making the corresponding maintenance operations more efficient). Therefore, the problem of relatively low reliability in monitoring the contact network grounding device in the prior art can be improved. Moreover, the circuit formed by the contact network grounding device itself is directly utilized, which can reduce the complexity of the circuit continuity monitoring device and reduce its volume. When installed at a location such as a tunnel port well, the installation space of the circuit continuity monitoring device will not be limited. In this way, its application scenarios will not be restricted. Therefore, it has high practical value. In addition, since the contact network grounding device includes a dual-line setting of a first contact network line and a second contact network line, a first return rail line and a second return rail line, the grounding reliability of the contact network grounding device can also be improved, thereby ensuring that the contact network can be effectively grounded during the maintenance of the contact network (rail), avoiding problems such as personal safety accidents caused by invalid grounding.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to make the above-mentioned objects, features and advantages of the present application more obvious and easy to understand, preferred embodiments are specifically cited below and described in detail with reference to the attached drawings.

FIG1 is a schematic diagram of an application scenario of a contact network grounding device provided in an embodiment of the present application.

FIG2 is a circuit diagram of an application scenario of the overhead contact network grounding device provided in an embodiment of the present application.

Icon: JD-grounding switch, CPU-processor, CT1-first excitation current transformer, CT2-first monitoring current transformer, T1-first signal transformer, R1-first current limiting resistor, I1-first excitation current measuring unit, I2-first monitoring current measuring unit, K1-first electronic switch, CT3-second excitation current transformer, CT4-second monitoring current transformer, T2-second signal transformer, R2-second current limiting resistor, I3-second excitation current measuring unit, I4-second monitoring current measuring unit, K2-second electronic switch, H1-first high withstand voltage unit, R3-third current limiting resistor, M-test signal control unit, DY-signal generator, I5-current measuring unit, H2-second high withstand voltage unit, U-voltage measuring unit, P1-induced voltage prevention unit.

DETAILED DESCRIPTION

In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. The components of the embodiments of the present application described and shown in the drawings here can be arranged and designed in various different configurations.

Therefore, the following detailed description of the embodiments of the present application provided in the accompanying drawings is not intended to limit the scope of the present application for which protection is sought, but merely represents selected embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without creative work are within the scope of protection of the present application.

As shown in Fig. 1, an embodiment of the present application provides a contact network grounding device, wherein the contact network grounding device may include a contact network grounding device and a loop continuity monitoring device, and the loop continuity monitoring device may be used to monitor the contact network grounding device.

In detail, the overhead contact network grounding device may include an overhead contact network line, an earthing switch and a return rail line. That is, the overhead contact network in the corresponding application scenario may be connected to the return rail through the overhead contact network line, the earthing switch and the return rail line.

In a first aspect, the overhead contact network line may include a first overhead contact network line and a second overhead contact network line, and/or the return rail line may include a first return rail line and a second return rail line.

For example, in an alternative embodiment, the contact network line includes a first contact network line and a second contact network line, and the return rail line includes a first return rail line. For another example, in a second alternative embodiment, the contact network line includes a first contact network line, and the return rail line includes a first return rail line and a second return rail line. For another example, in a third alternative embodiment, the contact network line includes a first contact network line and a second contact network line, and the return rail line includes a first return rail line and a second return rail line.

Wherein, when the overhead contact network line includes the first overhead contact network line and the second overhead contact network line, the first overhead contact network line and the second overhead contact network line are connected in parallel between the first end of the grounding knife switch (such as the positive pole of the grounding knife switch) and the overhead contact network. Based on this, while connecting the overhead contact network to the grounding knife switch, a first test loop of the first overhead contact network line, the second overhead contact network line and the overhead contact network can also be formed (which can be used for corresponding continuity detection, such as detecting the connection reliability between the overhead contact network line and the grounding knife switch, detecting the connection reliability between the overhead contact network line and the overhead contact network). When the return rail circuit includes the first return rail circuit and the second return rail circuit, the first return rail circuit and the second return rail circuit are connected in parallel between the second end of the grounding switch (such as the negative pole of the grounding switch) and the return rail. Based on this, when the return rail is connected to the grounding switch, a second test loop including the first return rail circuit, the second return rail circuit and the return rail can also be formed (which can be used to perform corresponding continuity detection, such as detecting the connection reliability between the return rail circuit and the grounding switch, and detecting the connection reliability between the return rail circuit and the return rail).

Based on this, by setting up double contact network lines and/or double return rail lines, the continuity of the lines can be made more reliable. For example, when one contact network line or return rail line is not connected continuously, the other contact network line or return rail line can also provide an effective loop connection.

In a second aspect, the loop continuity monitoring device may include a first monitoring module and/or a second monitoring module. That is, the loop continuity monitoring device may include at least one monitoring module, for example, the loop continuity monitoring device may include only the first monitoring module, or the loop continuity monitoring device may include only the second monitoring module, or the loop continuity monitoring device may include the first monitoring module and the second monitoring module.

Among them, the first monitoring module is arranged in cooperation with the first test loop, and can be used to monitor the loop continuity of the first test loop. For example, when the monitoring result reflects that the first test loop is discontinuous, the result that the connection between the overhead contact line and the earthing knife switch is unreliable, and the connection between the overhead contact line and the overhead contact line is unreliable can be obtained. The second monitoring module is arranged in cooperation with the second test loop, and can be used to monitor the loop continuity of the second test loop. For example, when the monitoring result reflects that the second test loop is discontinuous, the result that the connection between the return rail line and the earthing knife switch is unreliable, and the connection between the return rail line and the return rail is unreliable can be obtained.

In addition, the specific structure of the loop continuity monitoring device can refer to the relevant description below.

In conjunction with Fig. 2, the embodiment of the present application further provides a loop continuity monitoring device applicable to the above-mentioned overhead line grounding equipment, wherein the loop continuity monitoring device can be used to monitor the overhead line grounding device included in the overhead line grounding equipment.

As described above, the contact network grounding device may include a contact network line, a grounding knife switch JD and a return rail line. The contact network line may include a first contact network line and a second contact network line, and/or the return rail line may include a first return rail line and a second return rail line. When the contact network line includes the first contact network line and the second contact network line, the first contact network line and the second contact network line may be connected in parallel between the first end of the grounding knife switch JD and the contact network to form a first test loop including the first contact network line, the second contact network line and the contact network (test loop I as shown in Figure 2). When the return rail line includes the first return rail line and the second return rail line, the first return rail line and the second return rail line may be connected in parallel between the second end of the grounding knife switch JD and the return rail to form a second test loop including the first return rail line, the second return rail line and the return rail (test loop II as shown in Figure 2).

As described above, the loop continuity monitoring device may include a first monitoring module and/or a second monitoring module, such as including at least one of the first monitoring module and the second monitoring module. The first monitoring module is arranged in conjunction with the first test loop, and can be used to monitor the loop continuity of the first test loop. The second monitoring module is arranged in conjunction with the second test loop, and can be used to monitor the loop continuity of the second test loop.

Based on the above content, since the contact network line includes the first contact network line and the second contact network line which can form a first test loop with the contact network, the loop continuity monitoring of the first test loop can be performed separately. Similarly, since the return rail line includes the first return rail line and the second return rail line which can form a second test loop with the return rail, the loop continuity monitoring of the second test loop can also be performed separately. In this way, loop continuity monitoring with a smaller granularity can be achieved, thereby improving the reliability of loop continuity monitoring and facilitating abnormality positioning (making the corresponding maintenance operations more efficient). Therefore, the problem of relatively low reliability in monitoring the contact network grounding device in the prior art can be improved. Moreover, the loop formed by the contact network grounding device itself is directly utilized, which can reduce the complexity of the loop continuity monitoring device and reduce its volume. When installed at a location such as a tunnel port well, the installation space of the loop continuity monitoring device will not be limited. In this way, its application scenarios will not be restricted. Therefore, it has a high practical value. In addition, since the contact network grounding device includes a dual-line setting of a first contact network line and a second contact network line, a first return rail line and a second return rail line, the grounding reliability of the contact network grounding device can also be improved, thereby ensuring that the contact network can be effectively grounded during the maintenance of the contact network, avoiding problems such as personal safety accidents caused by invalid grounding.

Exemplarily, in an alternative embodiment, the loop continuity monitoring device may further include a processor CPU. Furthermore, the first monitoring module may include a first excitation current transformer CT1 and a first monitoring current transformer CT2, the first excitation current transformer CT1 and the first monitoring current transformer CT2 may be respectively arranged in the first test loop, and the specific arrangement positions may not be limited, for example, the first excitation current transformer CT1 may be arranged in the first contact network line, the first monitoring current transformer CT2 may be arranged in the second contact network line, or, in other embodiments, the positions may be interchanged.

Based on this, the processor CPU can control the external power supply to provide the first current to the first excitation current transformer CT1. If the first monitoring current transformer CT2 outputs the second current, it is determined that the first test loop is in a closed connection state. If the first monitoring current transformer CT2 does not output the second current, it is determined that the first test loop is not in a closed connection state (such as the connection between the contact network line and the contact network is unreliable, such as the connection between the A1 and B1 contact points is unreliable, the connection between the contact network line and the grounding switch JD is unreliable, such as the connection of the C1 contact point is unreliable).

Among them, the first excitation current transformer CT1 can generate the first induced current in the first test loop in a closed connection state in response to the first current, so that the first monitoring current transformer CT2 can output the second current in response to the first induced current. That is to say, as long as the processor CPU can detect that the first monitoring current transformer CT2 outputs the second current, it can be determined that the first test loop is in a closed connection state. On the contrary, when the first test loop is not in a closed connection state (such as the connection point of the line is disconnected), the first excitation current transformer CT1 cannot generate the first induced current in the first test loop that is not in a closed connection state in response to the first current, so that the first monitoring current transformer CT2 cannot output the second current, so that when the processor CPU detects that the first monitoring current transformer CT2 does not output the second current, it can determine that the first test loop is not in a closed state.

For example, an AC240V voltage source (frequency 50Hz) can obtain a current with a frequency of 50Hz through the first current limiting resistor R1 after passing through the first signal transformer T1 (transformation ratio is T) (the current can be monitored by the first excitation current measuring unit I1 and transmitted to the processor CPU). The current is transmitted to the first excitation current transformer CT1 (transformation ratio is n1) as an input signal. At this time, an AC induced current _I01 with the same frequency will be induced in the primary closed loop (such as the first test loop). When and only when the primary closed loop is in a closed connection state, the first monitoring current transformer CT2 (transformation ratio is n2) can sense the current _I01 and output the current (the current can be monitored by the first monitoring current measuring unit I2 and transmitted to the processor CPU). If the primary closed loop is disconnected, the current _I01 cannot be sensed in the primary closed loop, and the first monitoring current transformer CT2 has no output current.

In addition, in some alternative implementations, a first electronic switch K1 may be connected between the first current limiting resistor R1 and the first excitation current transformer CT1, so that the processor CPU may control whether the AC240V voltage source provides current to the first excitation current transformer CT1 through the first electronic switch K1.

For example, in an alternative embodiment, the loop continuity monitoring device may further include a processor CPU. In addition, the second monitoring module may include a second excitation current transformer CT3 and a second monitoring current transformer CT4, and the second excitation current transformer CT3 and the second monitoring current transformer CT4 may be respectively arranged in the second test loop, and the specific arrangement position may not be limited, for example, the second excitation current transformer CT3 may be arranged in the first return rail line, and the second monitoring current transformer CT4 may be arranged in the second return rail line, or, in other embodiments, the positions may also be interchanged.

Based on this, the processor CPU can control the external power supply to provide a third current to the second excitation current transformer CT3. If the second monitoring current transformer CT4 outputs the fourth current, it is determined that the second test loop is in a closed connection state. If the second monitoring current transformer CT4 does not output the fourth current, it is determined that the second test loop is not in a closed connection state (such as the connection between the return rail line and the return rail is unreliable, such as the connection between the A2 and B2 contact points is unreliable, the connection between the return rail line and the grounding switch JD is unreliable, such as the connection of the C2 contact point is unreliable).

Among them, the second excitation current transformer CT3 can generate a second induced current in the second test loop in a closed connection state in response to the third current, and the second monitoring current transformer CT4 can output the fourth current in response to the second induced current. That is to say, as long as the processor CPU can detect that the second monitoring current transformer CT4 outputs the fourth current, it can be determined that the second test loop is in a closed connection state. On the contrary, when the second test loop is not in a closed connection state (such as the connection point of the line is disconnected), the second excitation current transformer CT3 cannot generate a second induced current in the second test loop that is not in a closed connection state in response to the third current. In this way, the second monitoring current transformer CT4 cannot output the fourth current, so that when the processor CPU detects that the second monitoring current transformer CT4 does not output the fourth current, it can determine that the second test loop is not in a closed state.

For example, an AC240V voltage source (frequency 50Hz) can obtain a current with a frequency of 50Hz through the second current limiting resistor R2 after passing through the second signal transformer T2 (transformation ratio is T) (the current can be monitored by the second excitation current measuring unit I3 and transmitted to the processor CPU). The current is transmitted to the second excitation current transformer CT3 (transformation ratio is n1) as an input signal. At this time, an AC induced current _I02 with the same frequency will be induced in the primary closed loop (such as the second test loop). When and only when the primary closed loop is in a closed connection state, the second monitoring current transformer CT4 (transformation ratio is n2) can sense the current _I02 and output the current (the current can be monitored by the second monitoring current measuring unit I4 and transmitted to the processor CPU). If the primary closed loop is disconnected, the current _I02 cannot be sensed in the primary closed loop, and the second monitoring current transformer CT4 does not output current.

In addition, in some alternative implementations, a second electronic switch K2 may be connected between the second current limiting resistor R2 and the second excitation current transformer CT3, so that the processor CPU may control whether the AC240V voltage source provides current to the second excitation current transformer CT3 through the second electronic switch K2.

For example, in an alternative embodiment, the loop continuity monitoring device may further include a third monitoring module. The third monitoring module is configured in conjunction with the grounding switch JD, and may be used to monitor the loop continuity of the grounding switch JD, such as monitoring the closing condition (status) of the grounding switch JD.

For example, in an alternative embodiment, the third monitoring module may include a first high withstand voltage unit H1, a third current limiting resistor R3, a test signal control unit M, a signal generator DY, a current measuring unit I5, a second high withstand voltage unit H2 and a voltage measuring unit U.

In detail, the first end of the first high withstand voltage unit H1 is connected to the first end of the grounding knife switch JD. The first end of the third current limiting resistor R3 is connected to the second end of the first high withstand voltage unit H1. The first end of the test signal control unit M is connected to the second end of the third current limiting resistor R3, and the second end of the test signal control unit M is connected to the processor CPU. The first end of the signal generator DY is connected to the third end of the test signal control unit M, and the second end of the signal generator DY is connected to the processor CPU. The first end of the current measuring unit I5 is connected to the third end of the signal generator DY, and the second end of the current measuring unit I5 is connected to the processor CPU. The first end of the second high withstand voltage unit H2 is connected to the second end of the grounding knife switch JD, and the second end of the second high withstand voltage unit H2 is connected to the third end of the current measuring unit I5 (in this way, a test loop III as shown in Figure 2 can be formed). The first end of the voltage measuring unit U is connected to the second end of the first high withstand voltage unit H1 , the second end of the voltage measuring unit U is connected to the second end of the second high withstand voltage unit H2 , and the third end of the voltage measuring unit U is connected to the processor CPU.

Based on this, in the actual test process, after the grounding knife switch JD is closed, the first high withstand voltage unit H1 is closed, and the second high withstand voltage unit H2 is closed, the processor CPU measures a body potential (such as U1) through the voltage measurement unit U, and then controls the test signal control unit M to be closed (conducted), so that the signal generator DY outputs a test signal (the signal generator DY can be a power supply device). In this way, the processor CPU measures a test potential (such as U2) through the voltage measurement unit U, and measures a test current (such as I ₀₃ as shown in Figure 2) through the current measurement unit I5. In this way, the corresponding loop resistance can be calculated, such as (U2-U1)/I ₀₃ , wherein, by excluding the body potential U1, its interference can be reduced to a certain extent, so that the reliability of the obtained loop resistance can be higher. In some other implementations, in order to improve the monitoring efficiency, the body potential may not be tested, that is, the loop resistance is U2/I ₀₃ . In addition, after obtaining the loop resistance, the loop resistance can be compared with a reference resistance value (which can be a specific resistance value or a resistance value range), and then the closing reliability monitoring result of the grounding knife switch JD can be obtained. For example, when the obtained loop resistance is greater than the reference resistance value, it indicates that the closing reliability of the grounding knife switch JD is not high (such as the situation that the closing of the grounding knife switch JD becomes loose during long-term use, etc.). In this way, the loop resistance can not only indicate whether the switch is closed, but also indicate the specific closing situation.

For example, in an alternative implementation, the first high voltage withstand unit H1 is closed and the second high voltage withstand unit H2 can withstand a withstand voltage of 10 kV/1 min when it is opened.

For example, in an alternative implementation, the inventors of the present application have found through long-term research that when the voltage of the contact network is too high, the first high-voltage withstand unit H1 and the second high-voltage withstand unit H2 may be broken down, which will cause the subsequent devices (such as the voltage measurement unit U, the current measurement unit I5, etc.) to be damaged by high voltage. Based on this, the third monitoring module may also include an induction voltage prevention unit P1 (a switching device), the first end of the induction voltage prevention unit P1 is connected to the second end of the first high-voltage withstand unit H1, and the second end of the induction voltage prevention unit P1 is connected to the second end of the second high-voltage withstand unit H2, which is used to perform high-voltage protection on the third monitoring module. Based on this, during the measurement process, the induction voltage prevention unit P1 can be disconnected, and during the non-measurement process, the induction voltage prevention unit P1 can be closed, so that the subsequent devices are short-circuited to achieve high-voltage protection for the subsequent devices.

For example, in an alternative implementation, the third monitoring module may also include a contact network residual voltage isolation diode (specifically connected as G1 and G2 shown in FIG2 ). In this way, during the measurement process, if the contact network has residual voltage, the contact network residual voltage isolation diode has the characteristic of unidirectional conduction, and the reverse withstand voltage of the contact network residual voltage isolation diode can reach more than 2kV, which can play the role of residual voltage isolation, realize high-voltage isolation, and be safer and more reliable.

The embodiment of the present application also provides a loop continuity monitoring method that can be applied to the above-mentioned loop continuity monitoring device, which can be used to monitor the contact network grounding device.

Wherein, the contact network grounding device includes a contact network line, a grounding knife switch JD and a return rail line. The contact network line includes a first contact network line and a second contact network line, and/or the return rail line includes a first return rail line and a second return rail line. When the contact network line includes the first contact network line and the second contact network line, the first contact network line and the second contact network line are connected in parallel between the first end of the grounding knife switch JD and the contact network to form a first test loop including the first contact network line, the second contact network line and the contact network. When the return rail line includes the first return rail line and the second return rail line, the first return rail line and the second return rail line are connected in parallel between the second end of the grounding knife switch JD and the return rail to form a second test loop including the first return rail line, the second return rail line and the return rail. In addition, the loop continuity monitoring device includes a first monitoring module and/or a second monitoring module, the first monitoring module is arranged in conjunction with the first test loop, and the second monitoring module is arranged in conjunction with the second test loop.

The specific contents of the above-mentioned overhead line grounding device and loop continuity monitoring device are as described above. Based on this, the loop continuity monitoring method may include the following steps:

The first monitoring module can be used to monitor the loop continuity of the first test loop to obtain a corresponding first test loop continuity monitoring result, wherein the first test loop continuity monitoring result can be used to reflect the loop continuity of the first test loop, such as whether the first test loop is in a connected closed state or not in a connected closed state; and/or

The second monitoring module can be used to monitor the loop continuity of the second test loop to obtain a corresponding second test loop continuity monitoring result, wherein the second test loop continuity monitoring result can be used to reflect the loop continuity of the second test loop, such as whether the second test loop is in a connected closed state or not in a connected closed state.

Exemplarily, in an alternative embodiment, the loop continuity monitoring device further includes a processor CPU, and the first monitoring module includes a first excitation current transformer CT1 and a first monitoring current transformer CT2, the first excitation current transformer CT1 and the first monitoring current transformer CT2 are respectively arranged in the first test loop, the first excitation current transformer CT1 generates a first induced current in the first test loop in a closed connection state in response to the input first current, and the first monitoring current transformer CT2 outputs a second current in response to the first induced current. Based on this, the step of using the first monitoring module to monitor the loop continuity of the first test loop and obtain the corresponding first test loop continuity monitoring result can further include the following:

The processor CPU controls the external power supply to provide the first excitation current transformer CT1 with a first current, and monitors whether the first monitoring current transformer CT2 outputs a second current;

When the processor CPU detects that the first monitoring current transformer CT2 outputs the second current, it outputs a first test loop continuity monitoring result for characterizing that the first test loop is in a closed connection state. When the processor CPU detects that the first monitoring current transformer CT2 does not output the second current, it outputs a first test loop continuity monitoring result for characterizing that the first test loop is not in a closed connection state.

Exemplarily, in an alternative embodiment, after receiving a measurement instruction (such as from a control device such as a grounding device controller (PLC)), the processor CPU can close the first electronic switch K1, enable the grounding continuity monitoring function, and continuously measure the current of the first test loop for 2 seconds (the specific time length can be set), and then disconnect the first electronic switch K1 to exit the continuity monitoring function.

Exemplarily, in an alternative embodiment, the loop continuity monitoring device further includes a processor CPU, and the second monitoring module includes a second excitation current transformer CT3 and a second monitoring current transformer CT4, the second excitation current transformer CT3 and the second monitoring current transformer CT4 are respectively arranged in the second test loop, the second excitation current transformer CT3 generates a second induced current in the second test loop in a closed connection state in response to the input third current, and the second monitoring current transformer CT4 outputs a fourth current in response to the second induced current. Based on this, the step of using the second monitoring module to monitor the loop continuity of the second test loop and obtain the corresponding second test loop continuity monitoring result can further include the following:

The processor CPU controls the external power supply to provide the third current to the second excitation current transformer CT3, and monitors whether the second monitoring current transformer CT4 outputs the fourth current;

When the processor CPU detects that the second monitoring current transformer CT4 outputs the fourth current, it outputs a second test loop continuity monitoring result for characterizing that the second test loop is in a closed connection state. When the processor CPU detects that the second monitoring current transformer CT4 does not output the fourth current, it outputs a second test loop continuity monitoring result for characterizing that the second test loop is not in a closed connection state.

Exemplarily, in an alternative embodiment, after receiving a measurement instruction (such as from a control device such as a grounding device controller (PLC)), the processor CPU can close the second electronic switch K2, enable the grounding continuity monitoring function, and continuously measure the current of the second test loop for 2 seconds (the specific time length can be set), and then disconnect the second electronic switch K2 to exit the continuity monitoring function.

For example, in an alternative embodiment, the loop continuity monitoring device may further include a processor CPU and a third monitoring module. The third monitoring module includes a first high withstand voltage unit H1, a third current limiting resistor R3, a test signal control unit M, a signal generator DY, a current measuring unit I5, a second high withstand voltage unit H2 and a voltage measuring unit U. A first end of the first high withstand voltage unit H1 is connected to a first end of the grounding switch JD, a first end of the third current limiting resistor R3 is connected to a second end of the first high withstand voltage unit H1, a first end of the test signal control unit M is connected to a second end of the third current limiting resistor R3, a second end of the test signal control unit M is connected to the processor CPU, a first end of the signal generator DY is connected to a third end of the test signal control unit M, a second end of the signal generator DY is connected to the processor CPU, a first end of the current measuring unit I5 is connected to a third end of the signal generator DY, a second end of the current measuring unit I5 is connected to the processor CPU, a first end of the second high withstand voltage unit H2 is connected to a second end of the grounding switch JD, a second end of the second high withstand voltage unit H2 is connected to a third end of the current measuring unit I5, a first end of the voltage measuring unit U is connected to a second end of the first high withstand voltage unit H1, a second end of the voltage measuring unit U is connected to a second end of the second high withstand voltage unit H2, and a third end of the voltage measuring unit U is connected to the processor CPU. Based on this, the loop continuity monitoring method may further include the following steps:

After the grounding switch JD is closed, the first high withstand voltage unit H1 is closed, and the second high withstand voltage unit H2 is closed, the processor CPU controls the voltage measuring unit U to measure the voltage between the second end of the first high withstand voltage unit H1 and the second end of the second high withstand voltage unit H2 to obtain a first voltage;

After obtaining the first voltage, the processor CPU controls the signal generator DY to output a test current through the test signal control unit M and the third current limiting resistor R3, and controls the voltage measuring unit U to measure the voltage between the second end of the first high withstand voltage unit H1 and the second end of the second high withstand voltage unit H2 to obtain a second voltage, and controls the current measuring unit I5 to measure the test current;

The processor CPU determines the loop resistance of the grounding switch JD based on the first voltage, the second voltage and the test current (such as first calculating the voltage difference between the second voltage and the first voltage, and then calculating the ratio between the voltage difference and the test current), and determines the third loop continuity monitoring result corresponding to the grounding switch JD based on the loop resistance.

Based on the above, firstly, the connection method of upper and lower double cables (lines) can enhance the reliability of the contact network grounding device from a physical level, and at the same time facilitate the monitoring of the continuity of the cables of the contact network grounding device. Secondly, the loop continuity monitoring device is small in size, and the addition of the loop continuity monitoring device has little impact on the external volume of the contact network grounding device, which can meet the installation requirements on site. Thirdly, there is no risk of direct contact between the loop continuity monitoring device and the high-voltage part of the traction power supply circuit. When the traction power supply system is operating normally, even if the loop continuity monitoring device is damaged, it will not affect the normal operation of the power supply system. Fourthly, the function configuration of the loop continuity monitoring device is flexible, and whether to enable the grounding continuity monitoring function can be configured through the background. Fifthly, within 2 seconds before and after the switch is closed (the time can be set, and the total test time does not exceed 5 seconds), the test signal can be injected, and it will automatically exit after the test is completed. The test signal frequency can be customized according to user requirements to ensure that it will not affect the normal operation of the traction iron signal system. Sixthly, when the measurement conditions are met, a single loop continuity monitoring device can meet the measurement function, without the need to cooperate with external equipment for testing, and has high reliability. Seventhly, the continuity test of the grounding knife switch and the continuity test of the wiring cable can be performed independently, the activation of the test loop can be configured through software, and the grounding knife switch can be tested in different ways before closing (testing the continuity of the wiring cable) and after closing (testing the continuity of the grounding knife switch), which is more reliable. Eighthly, the specific fault point can be located: upper wiring continuity fault (A1, B1 as shown in Figure 2), lower wiring continuity fault (A2, B2 as shown in Figure 2), knife switch continuity fault, so that it can be easily repaired.

In summary, in the overhead contact network grounding equipment, loop continuity monitoring device and method provided by the present application, the loop continuity monitoring device is used to monitor the overhead contact network grounding device, the overhead contact network grounding device includes an overhead contact network line, an earthing knife switch and a return rail line, the overhead contact network line includes a first overhead contact network line and a second overhead contact network line, constituting a first test loop, and the return rail line includes a first return rail line and a second return rail line, constituting a second test loop. The loop continuity monitoring device includes a first monitoring module and a second monitoring module, which are used to monitor the loop continuity of the first test loop and the second test loop respectively. Based on the above content, since the contact network line includes the first contact network line and the second contact network line which can form a first test loop with the contact network, the loop continuity monitoring of the first test loop can be performed separately. Similarly, since the return rail line includes the first return rail line and the second return rail line which can form a second test loop with the return rail, the loop continuity monitoring of the second test loop can also be performed separately. In this way, loop continuity monitoring with a smaller granularity can be achieved, thereby improving the reliability of loop continuity monitoring and facilitating abnormality positioning (making the corresponding maintenance operations more efficient). Therefore, the problem of relatively low reliability in monitoring the contact network grounding device in the prior art can be improved. Moreover, the loop formed by the contact network grounding device itself is directly utilized, which can reduce the complexity of the loop continuity monitoring device and reduce its volume. When installed at a location such as a tunnel port well, the installation space of the loop continuity monitoring device will not be limited. In this way, its application scenarios will not be restricted. Therefore, it has a high practical value. In addition, since the contact network grounding device includes a dual-line setting of a first contact network line and a second contact network line, a first return rail line and a second return rail line, the grounding reliability of the contact network grounding device can also be improved, thereby ensuring that the contact network can be effectively grounded during the maintenance of the contact network, avoiding problems such as personal safety accidents caused by invalid grounding.

The above description is only the preferred embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims (9)

1. A loop continuity monitoring device, characterized in that it is used to monitor a contact network grounding device, wherein the contact network grounding device comprises a contact network line, a grounding switch and a return rail line, the contact network line comprises a first contact network line and a second contact network line, and/or the return rail line comprises a first return rail line and a second return rail line; When the overhead contact network line includes the first overhead contact network line and the second overhead contact network line, the first overhead contact network line and the second overhead contact network line are connected in parallel between the first end of the grounding knife switch and the overhead contact network to form a first test loop including the first overhead contact network line, the second overhead contact network line and the overhead contact network; When the return rail circuit includes the first return rail circuit and the second return rail circuit, the first return rail circuit and the second return rail circuit are connected in parallel between the second end of the grounding knife switch and the return rail to form a second test loop including the first return rail circuit, the second return rail circuit and the return rail; Wherein, the loop continuity monitoring device includes a first monitoring module and/or a second monitoring module, the first monitoring module is arranged in cooperation with the first test loop, and the first monitoring module is used to monitor the loop continuity of the first test loop; the second monitoring module is arranged in cooperation with the second test loop, and the second monitoring module is used to monitor the loop continuity of the second test loop; Wherein, the loop continuity monitoring device further includes a processor, and the first monitoring module includes a first excitation current transformer and a first monitoring current transformer, and the first excitation current transformer and the first monitoring current transformer are respectively arranged in the first test loop; wherein, after the processor controls the external power supply to provide the first excitation current transformer with the first current, if the first monitoring current transformer outputs the second current, it is determined that the first test loop is in a closed connection state; if the first monitoring current transformer does not output the second current, it is determined that the first test loop is not in a closed connection state; Furthermore, the first excitation current transformer generates a first induced current in the first test loop in a closed connection state in response to the first current, and the first monitoring current transformer outputs the second current in response to the first induced current. 2. A contact network grounding device, characterized in that it comprises a contact network grounding device and a loop continuity monitoring device, wherein the contact network grounding device comprises a contact network line, a grounding knife switch and a return rail line, and the contact network line, the grounding knife switch and the return rail line are connected in series between the contact network and the return rail, and are used to perform grounding control on the contact network and the return rail; The contact network line includes a first contact network line and a second contact network line, and/or the return rail line includes a first return rail line and a second return rail line; When the overhead contact network line includes the first overhead contact network line and the second overhead contact network line, the first overhead contact network line and the second overhead contact network line are connected in parallel between the first end of the grounding knife switch and the overhead contact network to form a first test loop including the first overhead contact network line, the second overhead contact network line and the overhead contact network; When the return rail circuit includes the first return rail circuit and the second return rail circuit, the first return rail circuit and the second return rail circuit are connected in parallel between the second end of the grounding knife switch and the return rail to form a second test loop including the first return rail circuit, the second return rail circuit and the return rail; The loop continuity monitoring device includes a first monitoring module and/or a second monitoring module, the first monitoring module is arranged in cooperation with the first test loop, and the first monitoring module is used to monitor the loop continuity of the first test loop; the second monitoring module is arranged in cooperation with the second test loop, and the second monitoring module is used to monitor the loop continuity of the second test loop; Wherein, the loop continuity monitoring device further includes a processor, and the first monitoring module includes a first excitation current transformer and a first monitoring current transformer, and the first excitation current transformer and the first monitoring current transformer are respectively arranged in the first test loop; wherein, after the processor controls the external power supply to provide the first excitation current transformer with the first current, if the first monitoring current transformer outputs the second current, it is determined that the first test loop is in a closed connection state; if the first monitoring current transformer does not output the second current, it is determined that the first test loop is not in a closed connection state; Furthermore, the first excitation current transformer generates a first induced current in the first test loop in a closed connection state in response to the first current, and the first monitoring current transformer outputs the second current in response to the first induced current. 3. The overhead contact grounding device according to claim 2, characterized in that the loop continuity monitoring device further comprises a processor, and the second monitoring module comprises a second excitation current transformer and a second monitoring current transformer, and the second excitation current transformer and the second monitoring current transformer are respectively arranged in the second test loop; wherein, after the processor controls the external power supply to provide the third current to the second excitation current transformer, if the second monitoring current transformer outputs the fourth current, it is determined that the second test loop is in a closed connection state; if the second monitoring current transformer does not output the fourth current, it is determined that the second test loop is not in a closed connection state; Furthermore, the second excitation current transformer generates a second induced current in the second test loop in a closed connection state in response to the third current, and the second monitoring current transformer outputs the fourth current in response to the second induced current. 4. The contact network grounding equipment according to any one of claims 2-3 is characterized in that the loop continuity monitoring device also includes a third monitoring module, wherein the third monitoring module is arranged in cooperation with the grounding switch to monitor the loop continuity of the grounding switch. 5. The contact network grounding device according to claim 4, characterized in that the loop continuity monitoring device further comprises a processor, and the third monitoring module comprises: A first high voltage withstand unit, wherein a first end of the first high voltage withstand unit is connected to a first end of the grounding switch; A current limiting resistor, wherein a first end of the current limiting resistor is connected to a second end of the first high withstand voltage unit; A test signal control unit, wherein a first end of the test signal control unit is connected to a second end of the current limiting resistor, and a second end of the test signal control unit is connected to the processor; A signal generator, wherein a first end of the signal generator is connected to a third end of the test signal control unit, and a second end of the signal generator is connected to the processor; a current measuring unit, wherein a first terminal of the current measuring unit is connected to a third terminal of the signal generator, and a second terminal of the current measuring unit is connected to the processor; A second high-voltage withstand unit, wherein a first end of the second high-voltage withstand unit is connected to a second end of the grounding switch, and a second end of the second high-voltage withstand unit is connected to a third end of the current measuring unit; A voltage measuring unit, wherein a first end of the voltage measuring unit is connected to a second end of the first high withstand voltage unit, a second end of the voltage measuring unit is connected to a second end of the second high withstand voltage unit, and a third end of the voltage measuring unit is connected to the processor. 6. The contact network grounding device according to claim 5, characterized in that the third monitoring module further comprises: An induced voltage prevention unit, wherein the first end of the induced voltage prevention unit is connected to the second end of the first high voltage withstand unit, the second end of the induced voltage prevention unit is connected to the second end of the second high voltage withstand unit, and the induced voltage prevention unit is used to perform high voltage protection on the third monitoring module. 7. A loop continuity monitoring method, characterized in that it is applied to a loop continuity monitoring device to monitor a contact network grounding device; The contact network grounding device comprises a contact network line, a grounding switch and a return rail line, the contact network line comprises a first contact network line and a second contact network line, and/or the return rail line comprises a first return rail line and a second return rail line; When the overhead contact network line includes the first overhead contact network line and the second overhead contact network line, the first overhead contact network line and the second overhead contact network line are connected in parallel between the first end of the earthing knife switch and the overhead contact network to form a first test loop including the first overhead contact network line, the second overhead contact network line and the overhead contact network; when the return rail line includes the first return rail line and the second return rail line, the first return rail line and the second return rail line are connected in parallel between the second end of the earthing knife switch and the return rail to form a second test loop including the first return rail line, the second return rail line and the return rail; Wherein, the loop continuity monitoring device includes a first monitoring module and/or a second monitoring module, the first monitoring module is arranged in cooperation with the first test loop, and the second monitoring module is arranged in cooperation with the second test loop; Wherein, the loop continuity monitoring method comprises: Using the first monitoring module, monitoring the loop continuity of the first test loop to obtain a corresponding first test loop continuity monitoring result; and/or Using the second monitoring module, monitoring the loop continuity of the second test loop to obtain a corresponding second test loop continuity monitoring result; Wherein, the loop continuity monitoring device further includes a processor, and the first monitoring module includes a first excitation current transformer and a first monitoring current transformer, the first excitation current transformer and the first monitoring current transformer are respectively arranged in the first test loop, the first excitation current transformer generates a first induced current in the first test loop in a closed connection state in response to the input first current, and the first monitoring current transformer outputs a second current in response to the first induced current, and the step of using the first monitoring module to monitor the loop continuity of the first test loop and obtain the corresponding first test loop continuity monitoring result includes: The processor controls the external power supply to provide the first excitation current transformer with a first current, and monitors whether the first monitoring current transformer outputs a second current; When the processor detects that the first monitoring current transformer outputs the second current, the processor outputs a first test loop continuity monitoring result used to characterize that the first test loop is in a closed connection state. When the processor detects that the first monitoring current transformer does not output the second current, the processor outputs a first test loop continuity monitoring result used to characterize that the first test loop is not in a closed connection state. 8. The loop continuity monitoring method according to claim 7, characterized in that the second monitoring module comprises a second excitation current transformer and a second monitoring current transformer, the second excitation current transformer and the second monitoring current transformer are respectively arranged in the second test loop, the second excitation current transformer generates a second induced current in the second test loop in a closed connection state in response to an input third current, and the second monitoring current transformer outputs a fourth current in response to the second induced current; The step of using the second monitoring module to monitor the loop continuity of the second test loop to obtain the corresponding second test loop continuity monitoring result includes: The processor controls the external power supply to provide the third current to the second excitation current transformer, and monitors whether the second monitoring current transformer outputs the fourth current; When the processor detects that the second monitoring current transformer outputs the fourth current, the processor outputs a second test loop continuity monitoring result for characterizing that the second test loop is in a closed connection state. When the processor detects that the second monitoring current transformer does not output the fourth current, the processor outputs a second test loop continuity monitoring result for characterizing that the second test loop is not in a closed connection state. 9. The loop continuity monitoring method according to claim 7, characterized in that the loop continuity monitoring device further comprises a processor and a third monitoring module; The third monitoring module includes a first high withstand voltage unit, a current limiting resistor, a test signal control unit, a signal generator, a current measuring unit, a second high withstand voltage unit and a voltage measuring unit, wherein the first end of the first high withstand voltage unit is connected to the first end of the grounding switch, the first end of the current limiting resistor is connected to the second end of the first high withstand voltage unit, the first end of the test signal control unit is connected to the second end of the current limiting resistor, the second end of the test signal control unit is connected to the processor, the first end of the signal generator is connected to the third end of the test signal control unit, the second end of the signal generator is connected to the processor, the first end of the current measuring unit is connected to the third end of the signal generator, the second end of the current measuring unit is connected to the processor, the first end of the second high withstand voltage unit is connected to the second end of the grounding switch, the second end of the second high withstand voltage unit is connected to the third end of the current measuring unit, the first end of the voltage measuring unit is connected to the second end of the first high withstand voltage unit, the second end of the voltage measuring unit is connected to the second end of the second high withstand voltage unit, and the third end of the voltage measuring unit is connected to the processor; Wherein, the loop continuity monitoring method further includes: After the grounding switch is closed, the first high-voltage withstand unit is closed, and the second high-voltage withstand unit is closed, the processor controls the voltage measuring unit to measure the voltage between the second end of the first high-voltage withstand unit and the second end of the second high-voltage withstand unit to obtain a first voltage; After obtaining the first voltage, the processor controls the signal generator to output a test current through the test signal control unit and the current limiting resistor, controls the voltage measuring unit to measure the voltage between the second end of the first high withstand voltage unit and the second end of the second high withstand voltage unit to obtain a second voltage, and controls the current measuring unit to measure the test current; The processor determines the loop resistance of the grounding switch based on the first voltage, the second voltage and the test current, and determines the third loop continuity monitoring result corresponding to the grounding switch based on the loop resistance.