A safety interlocking system and method based on hardware interlocking and electrical isolation

Abstract

The application discloses a kind of based on hardware interlock and electrical isolation safety interlocking system based on hardware interlock and electrical isolation safety interlocking system and method, the system includes operation terminal;Operation terminal includes: hardware interlock module, including separate interlocking relay and ground interlocking relay, separate interlocking relay is achieved by ground removal in position signal trigger and is separated from each other interlocking relay and is achieved by ground interlocking relay and is separated from each other interlocking relay and is separated from each other interlocking relay and is separated from each other interlocking relay and is separated from each other interlocking relay and is separated from each other interlocking relay and is separated from each other interlocking relay and is separated from each other interlocking relay and is separated from each other interlocking relay and is separated from each other interlocking relay and is separated from each other interlocking relay and is separated from each other interlocking relay and is separated from each other interlocking relay and is separated from each other interlocking relay and is separated from each other interlocking relay and is separated from each other interlocking relay and is separated from each other interlocking relay and is separated from each other interlocking relay and is separated from each other interlocking relay and is separated from each other interlocking relay and is separated from each other interlocking relay and is separated from each other interlocking relay and is separated from each other interlocking relay and is separated from each other interlocking relay and is separated from each other interlocking relay and is separated from each other interlocking relay and is separated from each other interlocking relay and is separated from each other interlocking relay and is separated from each other interlocking relay and is separated from each other interlocking relay and is separated from each other interlocking relay and is separated from each other interlocking relay and is separated from each other interlocking relay and is separated from each other interlocking relay and is separated from each other interlocking relay and is separated from each other interlocking relay and is separated from each other interlocking relay and is separated from each other interlocking relay and is separated from each other interlocking relay and is separated from each other interlocking relay and is separated from each other interlocking relay and is separated from each other interlocking relay and is separated from each other interlocking relay and is separated from each other interlocking relay and is separated from each other interlocking relay and is separated from each other interlocking relay and is separated from each other interlocking relay and is separated from each other interlocking relay and is separated from each other interlocking relay and is separated from each other interlocking

Description

Technical Field

[0001] This invention belongs to the field of electrical safety interlocking technology, specifically relating to a safety interlocking system and method based on hardware interlocking and electrical isolation. Background Technology

[0002] In the existing safety interlocking system, the control method for opening and closing the disconnecting switch and connecting / removing the grounding device is realized by direct cable drive control. At the same time, in order to prevent the contact network from "exploding" (i.e., connecting the grounding device when the disconnecting switch is open, or closing the disconnecting switch when the grounding device has not been removed), the measure adopted is to control the interlocking through software.

[0003] However, the above control methods and measures have the following drawbacks:

[0004] (1) The disconnecting switch side is a high-voltage power supply, which has dangerous factors such as arcing and creepage. These dangerous factors can cause unstable interference or surges on the disconnecting switch control box side to be connected in series or coupled to the safety interlocking control system, thereby causing distortion of the collected data or even damage to the data acquisition and control system.

[0005] (2) Software system failure or imprecise software logic may lead to incorrect output of control commands, which may cause the disconnector or grounding device to malfunction.

[0006] (3) Faults in the disconnector control box or grounding device control box can cause equipment to malfunction.

[0007] All of the above drawbacks can lead to "fireworks going off," posing a significant safety hazard. Summary of the Invention

[0008] To fundamentally prevent "explosion" incidents caused by software failures, signal interference, or malfunctions in the control boxes of disconnecting switches and grounding devices, thereby protecting the personal safety of relevant personnel and the property safety of equipment, this invention provides a safety interlocking system and method based on hardware interlocking and electrical isolation. This invention achieves hardware electrical interlocking between the disconnecting switch and grounding device by setting an interlocking module in the operating terminal. This ensures that even in the event of software failure or malfunctions in the disconnecting switch control box or grounding device control box, electrical interlocking can still prevent equipment malfunctions, thus avoiding "explosion" incidents and guaranteeing the stability, reliability, and safety of system operation.

[0009] This invention is achieved through the following technical solution:

[0010] A safety interlocking system based on hardware interlocking and electrical isolation, the system including an operating terminal;

[0011] The operating terminal includes:

[0012] The hardware interlock module includes an isolation interlock relay and a grounding interlock relay. The isolation interlock relay is triggered by a grounding removal signal to interlock the motor power supply and control power supply of the isolating switch. The grounding interlock relay is triggered by a disconnection signal to interlock the motor power supply and control power supply of the grounding device.

[0013] The system also includes a first control module, which is used to collect the status of the isolation interlock relay and the grounding interlock relay for hardware interlock self-test, and to issue software control commands or lock software control commands based on the hardware interlock results.

[0014] Existing safety interlocking systems suffer from problems such as malfunctions caused by software failures leading to misoperation of disconnect switches or grounding devices, or malfunctions caused by faults in the disconnect switches and grounding devices themselves. These problems can lead to "explosion" events, thus affecting system stability and safety. The safety interlocking system proposed in this invention employs a hardware electrical interlocking method to interlock the actions of disconnect switches and grounding devices at the hardware level. This ensures that "explosion" events will not occur in the event of software failure or a fault in the control box of the disconnect switch or grounding device. This fundamentally solves the problem of "explosion" caused by maloperation in existing technologies, improving the system's safety, reliability, and stability, while also protecting the personal safety of relevant personnel and the property safety of equipment.

[0015] In a preferred embodiment, the first control module of the present invention can also issue a fault alarm when the hardware interlock fails.

[0016] In a preferred embodiment, the system of the present invention further includes a remote control box for disconnecting switches;

[0017] The remote control box for the disconnecting switch includes:

[0018] The first isolation module achieves electrical isolation between the operating terminal and the primary high-voltage side of the isolating switch through an isolation transformer and an isolation-type AC-DC switching power supply;

[0019] The second isolation module, together with the first isolation module, is used to achieve electrical isolation between the primary high-voltage side of the disconnecting switch and the second control module.

[0020] The second control module is used to collect the opening and closing status of the disconnecting switch and upload the collected information to the first control module. The second control module is also used to receive software control commands from the first control module.

[0021] Existing systems suffer from unstable interference or surges on the primary high-voltage side of the disconnector switch control box, which can lead to distortion of data acquired on the secondary low-voltage side and even damage to the acquisition and control system. The system proposed in this invention, by introducing electrical isolation technology, achieves electrical isolation between the safety interlocking system and the primary high-voltage side of the disconnector switch. This prevents damage to the safety interlocking system from downstream high voltage and ensures the stability of the acquired signals, further improving the system's safety, stability, and reliability.

[0022] In a preferred embodiment, the first control module and the second control module of the present invention communicate using a network cable or an optical fiber.

[0023] In a preferred embodiment, the first isolation module of the present invention includes a first AC isolation transformer, a second AC isolation transformer, a third AC isolation transformer, a first isolated AC-DC switching power supply, and a second isolated AC-DC switching power supply.

[0024] The first AC isolation transformer is used to achieve electrical isolation between the motor power supply and control power supply of the isolating switch control box and the operating terminal;

[0025] The second AC isolation transformer is used to achieve electrical isolation between the power circuit of the isolation switch remote control box and the operating terminal;

[0026] The third AC isolation transformer is used to isolate the disconnection switch opening signal circuit in the disconnection switch control box from the operation terminal;

[0027] The first isolated AC-DC switching power supply is used to convert AC power into DC power to power the second control module and realize electrical isolation between the power circuit of the isolation switch remote control box and the second control module;

[0028] The second isolated AC-DC switching power supply is used to convert AC power into DC power, power the second isolation module, and isolate the disconnect switch open and close signal circuits in the disconnect switch control box from the second control module.

[0029] In a preferred embodiment, the second isolation module of the present invention includes a circuit breaker tripping status acquisition relay and a circuit breaker closing status acquisition relay;

[0030] The tripping signal acquisition relay is used to acquire the tripping signal of the isolating switch and to achieve electrical isolation between the isolating switch and the second control module. The closing signal acquisition relay is used to acquire the closing signal of the isolating switch and to achieve electrical isolation between the isolating switch and the second control module.

[0031] In a preferred embodiment, the isolation interlocking relay of the present invention is connected to the grounding removal signal via a direct cable connection, and the grounding interlocking relay is connected to the disconnecting switch tripping signal via a third AC isolation transformer.

[0032] On the other hand, the present invention also proposes a hardware interlocking method based on the above-mentioned safety interlocking system, the method comprising:

[0033] After the grounding device is removed, a grounding removal signal is generated. The grounding removal signal triggers the normally open contact of the isolation interlock relay to close. At this time, the power supply is output through the isolation interlock relay to the isolation switch control box to provide power supply for the isolation switch motor and control power.

[0034] After the disconnecting switch is fully open, a disconnecting switch open signal is generated. The disconnecting switch open signal triggers the normally open contact of the grounding interlock relay to close. At this time, the power supply is output through the grounding interlock relay to the grounding control box to provide power to the grounding device motor and control power.

[0035] In a preferred embodiment, the method of the present invention further includes:

[0036] The first control module collects the status of the isolation interlock relay and the grounding interlock relay, and in conjunction with the current operation process, determines whether the hardware interlock is successful. If the hardware interlock is successful, software control commands are allowed to be issued. If the hardware interlock is unsuccessful, a fault alarm is triggered and the software control commands are blocked.

[0037] In a preferred embodiment, the method of the present invention further includes:

[0038] The first control module receives the status information of the disconnecting switch opening relay and the disconnecting switch closing relay, and combines it with the status information of the disconnecting interlock relay and the grounding interlock relay to identify erroneous output of software control commands.

[0039] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0040] 1. This invention ensures that the disconnecting switch and the grounding device form an interlock independently of the software interlock through hardware electrical interlock, and further provides an interlocking basis for the software interlock logic. This fundamentally avoids the occurrence of "explosion" events caused by software failure, failure of the control box itself, etc., improves the safety, stability and reliability of the system, and protects the personal safety of relevant operators and the property safety of equipment.

[0041] 2. The present invention also ensures electrical isolation between the primary high-voltage side of the disconnecting switch and the safety interlocking equipment through an electrical isolation device, so as to avoid unstable interference or surges that may be generated in series or coupled into the safety interlocking control system when dangerous factors such as arcing or creepage occur on the disconnecting switch side, which could lead to distortion of the collected data or even damage to the data acquisition and control system.

[0042] 3. This invention can also collect the status of interlocking relays and disconnecting switch opening / closing (control) relays, and combine them with the on-site business process to add software interlocking control function and fault diagnosis function, making the interlocking system more complete and reliable, while improving the maintainability of the system. Attached Figure Description

[0043] The accompanying drawings, which are included to provide a further understanding of embodiments of the invention and form part of this application, do not constitute a limitation thereof. In the drawings:

[0044] Figure 1 This is a schematic diagram of the operation terminal and grounding control box according to an embodiment of the present invention.

[0045] Figure 2 This is a schematic diagram of the remote control box for the disconnecting switch according to an embodiment of the present invention.

[0046] Figure 3 This is a schematic diagram of the structure of the remote control box and the control box for the disconnecting switch according to an embodiment of the present invention.

[0047] Figure 4 This is a schematic diagram of the overall system structure combining hardware interlocking and electrical isolation according to an embodiment of the present invention.

[0048] Figure reference numerals and corresponding component names:

[0049] 1-Isolation AC-DC switching power supply A, 2-Isolation interlock relay, 3-Grounding interlock relay, 4-Isolation AC-DC switching power supply B, 5-PLC controller, 6-AC isolation transformer A, 7-AC isolation transformer B, 8-Isolation AC-DC switching power supply C, 9-AC isolation transformer C, 10-Isolation AC-DC switching power supply D, 11-Remote I / O unit, 12-Isolation switch opening control relay, 13-Isolation switch closing control relay, 14-Opening position acquisition relay, 15-Closing position acquisition relay, 16-Isolation switch control box motor power supply / control power supply, 17-Isolation switch opening position signal A, 18-Isolation switch opening position signal B, 19-Isolation switch closing position signal, 20-Grounding control box motor power supply / control power supply, 21-Grounding removal position signal. Detailed Implementation

[0050] In the following, the terms “comprising” or “may include” as used in various embodiments of the invention indicate the presence of an inventive function, operation, or element, and do not limit the addition of one or more functions, operations, or elements. Furthermore, as used in various embodiments of the invention, the terms “comprising,” “having,” and their cognates are intended only to indicate a specific feature, number, step, operation, element, component, or combination of the foregoing, and should not be construed as primarily excluding the presence of one or more other features, numbers, steps, operations, elements, components, or combinations of the foregoing, or adding one or more combinations of the foregoing.

[0051] In various embodiments of the invention, the expression "or" or "at least one of A and / or B" includes any combination or all combinations of the words listed simultaneously. For example, the expression "A or B" or "at least one of A and / or B" may include A, may include B, or may include both A and B.

[0052] The expressions used in the various embodiments of the present invention (such as "first," "second," etc.) may modify various constituent elements in the various embodiments, but do not limit the corresponding constituent elements. For example, the above expressions do not limit the order and / or importance of the elements. The above expressions are only used for the purpose of distinguishing one element from other elements. For example, a first user device and a second user device refer to different user devices, although both are user devices. For example, a first element may be referred to as a second element without departing from the scope of the various embodiments of the present invention, and similarly, a second element may also be referred to as a first element.

[0053] It should be noted that if a description is made of "connecting" one component to another, then the first component can be directly connected to the second component, and a third component can be "connected" between the first and second components. Conversely, when a component is "directly connected" to another component, it can be understood that there is no third component between the first and second components.

[0054] The terminology used in the various embodiments of the invention is for the purpose of describing particular embodiments only and is not intended to limit the various embodiments of the invention. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Unless otherwise defined, all terms used herein (including technical and scientific terms) have the same meaning as commonly understood by one of ordinary skill in the art to which the various embodiments of the invention pertain. The terms (such as those defined in a generally used dictionary) are to be interpreted as having the same meaning as in the context of the relevant technical field and are not to be interpreted as having an idealized or overly formal meaning, unless clearly defined in the various embodiments of the invention.

[0055] To make the objectives, technical solutions, and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the embodiments and accompanying drawings. The illustrative embodiments and descriptions of the present invention are only used to explain the present invention and are not intended to limit the present invention.

[0056] Example:

[0057] Existing safety interlocking systems suffer from drawbacks such as malfunctions caused by software failures leading to the misoperation of disconnecting switches or grounding devices, or malfunctions caused by faults in the disconnecting switches and grounding devices themselves. These drawbacks can lead to "explosions" (false alarms), affecting system stability and safety. Therefore, this embodiment proposes a safety interlocking system based on hardware interlocking and electrical isolation. The system proposed in this embodiment ensures that the actions of the disconnecting switch and grounding device are interlocked at the hardware level through hardware electrical interlocking. Specifically, when the disconnecting switch is in the open state, the power supply to the grounding device's motor and control is cut off, preventing the grounding device from completing the connection action. This ensures that no malfunction occurs when the software fails to issue a grounding device connection action command or when the control box malfunctions to trigger a connection action. Conversely, when the grounding device is in the connected state, the power supply to the disconnecting switch's motor and control is cut off, preventing the disconnecting switch from completing the opening action. Even if the software fails to issue a disconnecting switch opening action command or the control box malfunctions to trigger a connection action, no malfunction occurs, fundamentally preventing "explosions" and ensuring the stability and safety of system operation.

[0058] The safety interlocking system proposed in this embodiment includes an operating terminal, which comprises a hardware interlocking module and a control module A. The control module A mainly consists of a PLC controller, an isolated AC-DC switching power supply A, and a network interface unit. The PLC controller receives data such as the status of the field disconnect switch, the status of the grounding device, and the status of the voltage detection device through the network interface unit, and outputs disconnect switch opening / closing signals and grounding device connection / removal signals in combination with interlocking logic and operating instructions. The hardware interlocking module mainly consists of a disconnecting interlocking relay, a grounding interlocking relay, and an isolated AC-DC switching power supply B. The disconnecting interlocking relay interlocks the power supply of the disconnect switch motor or the disconnect switch control power supply through the grounding removal signal, and the grounding interlocking relay interlocks the power supply of the grounding device motor and the control power supply through the disconnect switch opening signal.

[0059] This embodiment sets up an interlock module in the operating terminal for hardware electrical interlocking between the disconnect switch and the grounding device. This ensures that even in the event of software failure or malfunction of the disconnect switch control box or the grounding device control box, the electrical interlocking can still prevent equipment malfunctions, thereby avoiding "explosion" events and ensuring the stability, reliability, and safety of the system operation.

[0060] Furthermore, existing safety interlocking systems suffer from problems such as damage to core interface equipment on the low-voltage side of the secondary side and abnormal data acquisition caused by primary-side high-voltage interference or surges. Therefore, this embodiment also implements relay isolation and switching power supply isolation by setting up isolation modules. This ensures electrical isolation between the safety interlocking system and the high-voltage side of the disconnector switch, preventing unstable interference or surges from occurring on the disconnector switch side due to arcing, creepage, or other dangerous factors from being connected in series or coupled into the safety interlocking control system. This avoids data distortion or even damage to the acquisition and control system, further improving the stability, reliability, and safety of the safety interlocking system. Specifically, the system in this embodiment also includes a remote control box for the disconnector switch, which includes isolation module A, isolation module B, and control module B. Control module B and control module A communicate via network cable or fiber optic cable, depending on the actual communication distance.

[0061] Specifically, isolation module A mainly consists of an AC isolation transformer and an isolated AC-DC switching power supply, used to achieve electrical isolation between the operating terminal and the high-voltage side of the disconnector switch. Isolation module B mainly consists of relays. Control module B is used to collect the status of the disconnector switch and upload the disconnector switch opening and closing status to control module A, while receiving disconnector switch opening / closing signals from control module A. Simultaneously, control module B also provides electrical isolation between the disconnector switch (i.e., isolation module B) opening and closing signals via relays. This embodiment achieves relay isolation and switching power supply isolation by setting isolation modules and control modules in the disconnector switch remote control box, ensuring electrical isolation between the safety interlocking system (i.e., the operating terminal) and the high-voltage side of the disconnector switch. When the high-voltage side of the disconnector switch is under high voltage, transformer isolation is achieved through the circuit composed of the AC isolation transformer and the isolated AC-DC switching power supply, while air isolation is achieved in the circuit using relays.

[0062] Furthermore, the PLC controller can also collect the status of grounding interlock relays, isolating interlock relays, isolating switch opening control relays, and isolating switch closing control relays, and combine this with the actual execution situation on site to add software interlocking control functions and fault diagnosis functions. That is, it can only issue action commands for isolating switches or grounding devices after ensuring that the interlock relays are in normal status, and determine the system fault situation by combining the status of the control relay equipment and the interlock relay equipment.

[0063] Figure 1 An example of an operating terminal and grounding device structure is provided, such as... Figure 1As shown, the operating terminal includes a hardware interlock module and a control module A. The hardware interlock module includes an isolated AC-DC switching power supply A1, a disconnecting interlock relay 2, and a grounding interlock relay 3. The isolated AC-DC switching power supply A1 converts 220V AC power to 24V DC power output to power the disconnecting interlock relay 2. The disconnecting interlock relay 2 and the grounding interlock relay 3 are triggered by the grounding removal signal 21 and the disconnecting switch tripping signal 17, respectively. The grounding device interlocks with the disconnecting switch as follows: after the grounding device is removed, the grounding removal signal 21 is triggered. At this time, the normally open contact of the disconnecting interlock relay 2 closes, and GK220V-L is output through the disconnecting interlock relay 2 to the motor power / control power supply 16 of the disconnecting switch control box. Similarly, the interlocking of the disconnecting switch with the grounding device is as follows: after the disconnecting switch is in the open position, the disconnecting switch open position signal 17 is triggered. At this time, the normally open contact of the grounding interlocking relay 3 is energized, and JD220V-L is output through the grounding interlocking relay 3 to the motor power supply / control power supply 20 of the grounding control box.

[0064] Control module A includes an isolated AC-DC switching power supply B4 and a PLC controller 5. The AC-DC switching power supply B4 converts 220V AC power to 24V DC power to supply power to PLC controller 5. PLC controller 5 can collect the status of grounding interlock relay 3 and isolating interlock relay 2, and perform software instruction interlocking and hardware interlocking self-tests based on the actual execution situation on site. That is, based on the current operation process, the PLC controller determines whether the hardware interlock is successful by collecting the status of the interlock relays, and simultaneously blocks the output of the current software control instructions based on the hardware interlock status. For example, if the isolating switch is in the closed state, then the current process is in the power-off process range. At this time, the hardware interlock module will perform hardware interlocking on the grounding device, so the isolating interlock relay is in the closed state and the grounding interlock relay is in the open state. If the PLC controller detects that both interlock relays are in the correct position, it will output a grounding connection command to perform software interlocking. If the PLC controller detects that the opening interlock relay is open or the grounding interlock relay is closed, it indicates that the equipment is in an abnormal state and a fault alarm will be triggered. After the hardware interlock is automatically completed, control module A will use the hardware interlock feedback status to identify whether the hardware interlock module has completed the interlock. If the hardware interlock is not completed, control module A will trigger a fault alarm and lock the software command. At this time, the disconnecting switch action and grounding device action commands must not be issued. For example, after the disconnecting switch is opened, if the PLC controller in control module A detects that the grounding interlock relay is energized and the opening interlock relay is open, it indicates that the hardware interlock is successful, and the grounding connection command can be issued.

[0065] Figures 2-3An example of an electrical isolation structure is provided, such as Figure 2 As shown, the remote control box for the disconnecting switch includes an isolation module A, an isolation module B, and a control module B. Isolation module A includes an AC isolation transformer A6, an AC isolation transformer B7, an AC isolation transformer C9, an isolated AC-DC switching power supply C8, and an isolated AC-DC switching power supply D10. AC isolation transformer A6 isolates the motor power supply / control power supply 16 of the disconnecting switch control box from the operating terminal, preventing power from flowing into the safety interlocking system during high-voltage downcurrent. AC isolation transformer B7 isolates the power supply circuit of the remote control box for the disconnecting switch from the operating terminal, preventing power from flowing into the safety interlocking system during high-voltage downcurrent. AC isolation transformer C9 isolates the disconnecting switch open signal A17 circuit in the remote control box from the operating terminal, preventing power from flowing into the safety interlocking system during high-voltage downcurrent. The isolated AC-DC switching power supply D10 converts 220V AC to 24V DC to power control module B and isolates the power circuit of the isolating switch remote control box from control module B, preventing power from flowing to control module B through the isolating switch remote control box power circuit during high voltage downtrends. The isolated AC-DC switching power supply C8 converts 220V AC to 24V DC to power the acquisition relays of isolating module B (including the open position acquisition relay 14 and the close position acquisition relay 15) and, together with isolating module B, isolates the isolating switch open position signal B18 and isolating switch close position signal 19 circuits in the isolating switch control box from control module B, preventing power from flowing to control module B through the isolating switch open position signal B18 (i.e., GKFZ) and isolating switch close position signal 19 (i.e., GKHZ) circuits in the isolating switch control box during high voltage downtrends.

[0066] Specifically, the isolation interlock relay 2 is connected to the grounding removal signal 21 via a direct cable connection, while the grounding interlock relay 3 is connected to the disconnect switch trip signal 17 via an AC isolation transformer C9. That is, the disconnect switch trip signal 17 is electrically isolated by the AC isolation transformer before being connected to the grounding interlock relay 3, thereby achieving hardware interlocking function on the basis of satisfying electrical isolation.

[0067] like Figure 3As shown, control module B collects the status of the disconnector switch closing and closing relay, and the status of the disconnector switch opening and opening relay through remote I / O unit 11. Based on the actual execution situation on site, it uploads the collected information to the PLC controller 5 of control module A in the operation terminal via network cable or optical fiber. At the same time, it receives the disconnector switch closing / opening commands issued by PLC controller 5 and outputs them to disconnector switch opening control relay 12 and disconnector switch closing control relay 13.

[0068] Based on this, the PLC controller 5 of control module A, combined with the status of the hardware interlock relays, can accurately monitor the status of the closing and opening relays of the isolating switch in real time, thereby effectively identifying whether there are software erroneous outputs and triggering fault alarms. This embodiment improves the reliability and security of the system software control by acquiring the status of the isolating interlock relays, grounding interlock relays, isolating switch opening relays, and isolating switch closing relays, and then performing software interlocking logic judgments and alarms. This also provides more accurate and reliable technical support and basis for equipment fault diagnosis and preventative maintenance.

[0069] Combining the above hardware interlocking and electrical isolation structures, the following is obtained: Figure 4 The schematic diagram of the overall structure of the safety interlocking system shown illustrates two key aspects. Firstly, the system employs hardware electrical interlocking to interlock the actions of the disconnecting switch and grounding device at the hardware level. This ensures that malfunctions and "explosion" events will not occur in the event of software failure or a fault in the disconnecting switch / grounding device control box itself, thereby improving the reliability and safety of the system and protecting the personal safety of personnel and the property of equipment. Secondly, an electrical isolation device is introduced to ensure electrical isolation between the safety interlocking system and the primary high-voltage side of the disconnecting switch. This prevents damage to the safety interlocking system from downstream high voltage and ensures the stability of the collected information, further enhancing the system's safety, stability, and reliability. Furthermore, the combination of hardware electrical interlocking and electrical isolation allows for the collection and feedback of information on the status of critical components. This further strengthens and enhances the software interlocking logic and fault diagnosis aspects. Specifically, the system ensures that the disconnecting switch or grounding action command is issued only after the interlocking relay is in normal condition. The system also combines the status of the control relay equipment and the interlocking relay equipment to locate system faults, making the safety interlocking system more comprehensive and reliable, and improving its maintainability.

[0070] It should be noted that, Figure 1-4 This is merely an illustrative example and does not limit the hardware interlocking and electrical isolation structures. Hardware interlocking can operate independently of software interlocking, enabling interlocking of the actions of disconnecting switches and grounding switches to prevent "explosion" events and improve the safety of on-site maintenance operations.

[0071] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A safety interlocking system based on hardware interlocking and electrical isolation, characterized in that, The system includes an operating terminal; The operating terminal includes: The hardware interlock module includes an isolation interlock relay and a grounding interlock relay. The isolation interlock relay is triggered by a grounding removal signal to interlock the motor power supply and control power supply of the isolating switch. The grounding interlock relay is triggered by a disconnection signal to interlock the motor power supply and control power supply of the grounding device. And a first control module, which is used to collect the status of the isolation interlock relay and the grounding interlock relay to perform hardware interlock self-test, and to issue software control commands or lock software control commands according to the hardware interlock results. The system also includes a remote control box for disconnecting switches; The remote control box for the disconnecting switch includes: The first isolation module achieves electrical isolation between the operating terminal and the primary high-voltage side of the isolating switch through an isolation transformer and an isolation-type AC-DC switching power supply; The second isolation module, together with the first isolation module, is used to achieve electrical isolation between the primary high-voltage side of the disconnecting switch and the second control module. The second control module is used to collect the opening and closing status of the disconnecting switch and upload the collected information to the first control module. The second control module is also used to receive software control commands from the first control module.

2. A safety interlock system based on hardware interlocking and electrical isolation as claimed in claim 1, wherein, The first control module can also issue a fault alarm when the hardware interlock fails.

3. A safety interlock system based on hardware interlocking and electrical isolation as claimed in claim 1, wherein, The first control module and the second control module communicate using a network cable or optical fiber.

4. The safety interlock system based on hardware interlocking and electrical isolation of claim 1, wherein, The first isolation module includes a first AC isolation transformer, a second AC isolation transformer, a third AC isolation transformer, a first isolated AC-DC switching power supply, and a second isolated AC-DC switching power supply; The first AC isolation transformer is used to achieve electrical isolation between the motor power supply and control power supply of the isolating switch control box and the operating terminal; The second AC isolation transformer is used to achieve electrical isolation between the power circuit of the isolation switch remote control box and the operating terminal; The third AC isolation transformer is used to isolate the disconnection switch opening signal circuit in the disconnection switch control box from the operation terminal; The first isolated AC-DC switching power supply is used to convert AC power into DC power to power the second control module and realize electrical isolation between the power circuit of the isolation switch remote control box and the second control module; The second isolated AC-DC switching power supply is used to convert AC power into DC power, power the second isolation module, and isolate the disconnect switch open and close signal circuits in the disconnect switch control box from the second control module.

5. A safety interlocking system based on hardware interlocking and electrical isolation according to claim 1, characterized in that, The second isolation module includes a tripping position acquisition relay and a closing position acquisition relay; The tripping signal acquisition relay is used to acquire the tripping signal of the isolating switch and to achieve electrical isolation between the isolating switch and the second control module. The closing signal acquisition relay is used to acquire the closing signal of the isolating switch and to achieve electrical isolation between the isolating switch and the second control module.

6. A safety interlock system based on hardware interlocking and electrical isolation as claimed in claim 4, wherein, The isolation interlock relay is connected to the grounding removal signal via a direct cable connection, and the grounding interlock relay is connected to the disconnect switch tripping signal via a third AC isolation transformer.

7. Hardware interlocking method of a safety interlocking system according to any one of claims 1 to 6, characterized in that The method includes: After the grounding device is removed, a grounding removal signal is generated. The grounding removal signal triggers the normally open contact of the isolation interlock relay to close. At this time, the power supply is output through the isolation interlock relay to the isolation switch control box to provide power supply for the isolation switch motor and control power. After the disconnecting switch is fully open, a disconnecting switch open signal is generated. The disconnecting switch open signal triggers the normally open contact of the grounding interlock relay to close. At this time, the power supply is output through the grounding interlock relay to the grounding control box to provide power to the grounding device motor and control power.

8. The hardware interlocking method according to claim 7, characterized in that, The method further includes: The first control module collects the status of the isolation interlock relay and the grounding interlock relay, and in conjunction with the current operation process, determines whether the hardware interlock is successful. If the hardware interlock is successful, software control commands are allowed to be issued. If the hardware interlock is unsuccessful, a fault alarm is triggered and the software control commands are blocked.

9. The hardware interlock method of claim 8, wherein, The method further includes: The first control module receives the status information of the disconnecting switch opening relay and the disconnecting switch closing relay, and combines it with the status information of the disconnecting interlock relay and the grounding interlock relay to identify erroneous output of software control commands.

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