Switch, switch blade state signal regeneration method and system based on network data reuse

Abstract

The application provides a switch, a switch blade state signal regeneration method and system based on network data reuse, relates to the technical field of power systems, and solves the problems of no spare contact point of old equipment and the need to lay secondary cables in the traditional way. The system is composed of an existing NCS monitoring system station control layer switch, a remote communication device and a programmable PLC. The remote communication device accesses the switch to convert network communication protocol downlink data into serial communication port downlink data. The PLC receives the data and executes the switch blade to output a passive switch contact point signal. The method includes data acquisition, protocol conversion, logical discrimination and signal regeneration output steps. The application does not need to modify the primary equipment, add secondary cables and network security equipment, can edit multiple state contact points, adapt to the needs of multiple secondary systems, can also be extended to protection control, metering switching and other power system scenarios, and has strong practicality and generalization.

Description

Technical Field

[0001] This invention relates to the field of power system technology, and specifically to a method and system for regenerating switch and disconnector status signals based on network data reuse. Background Technology

[0002] With the deepening of capacity replacement and expansion projects in the power system, the requirements for the level of power plant automation control are increasing. Many advanced automation functions, such as the metering of energy at the point of contact under self-generation and self-consumption conditions, microcomputer-based anti-misoperation interlocking under complex operating modes, and protection control optimization, all rely on the core prerequisite of being able to obtain the position status signals of equipment such as switches and disconnectors in the primary power system in real time and accurately.

[0003] In traditional technical solutions, the standard practice for secondary equipment such as protection devices, meters, and automatic control devices to obtain status signals from primary equipment is to directly draw physical wiring from the auxiliary contacts of circuit breakers and disconnectors in the high-voltage switchgear as secondary control cables, transmitting the open or closed position signals to the secondary equipment in the form of passive contacts. However, for many power plants that have been in operation for many years, the spare contact resources of the terminal blocks in the switchgear of their primary equipment have long been exhausted, making it impossible to provide additional hard-wired channels for newly added advanced control functions. To solve this problem, the traditional approach requires technical modifications to the operating primary high-voltage equipment to increase spare contacts and to re-lay long-distance secondary control cables. This approach is not only large in scale and costly, but also requires power outages for construction on the operating equipment, seriously affecting the safe and stable operation of the power plant, making it extremely difficult to implement.

[0004] Therefore, there is an urgent need in this field for an innovative technical approach that can reliably regenerate the required primary equipment status signals for downstream secondary systems without modifying primary equipment or adding secondary cables, in order to support various advanced automation applications. Summary of the Invention

[0005] In view of this, in order to overcome the shortcomings of the prior art, the purpose of this invention is to provide a method and system for regenerating switch and disconnector status signals based on network data reuse. This method abandons the traditional path of directly obtaining signals from the physical contacts of primary equipment, and instead utilizes the digitized and networked real-time data in the existing monitoring system of the power plant. Through the process of network acquisition, protocol conversion, logic processing, and signal regeneration, a completely new and freely definable switch signal channel is created for the downstream system.

[0006] To solve the above-mentioned technical problems, the present invention adopts the following technical solution: In a first aspect, the present invention provides a switch and disconnector status signal regeneration system based on network data reuse, comprising an existing NCS monitoring system station control layer switch, a remote communication device and at least two programmable PLCs connected in sequence. The NCS monitoring system station control layer switch is used to output downlink data of network communication protocol containing information on the original status of power plant switches and disconnectors, unit operation mode and current flow direction. The remote communication device is equipped with an RJ Ethernet port and a serial communication port. The RJ Ethernet port is connected to the station control layer switch of the NCS monitoring system. The remote communication device has a built-in protocol conversion module, which is used to convert the received network communication protocol downlink data into serial communication port downlink data and transmit it outward through the serial communication port. The programmable PLC is connected to the serial communication port of the remote communication device, and has a built-in switch and knife switch logic discrimination algorithm for receiving downlink data from the serial communication port and performing logic discrimination operations. The programmable PLC's switch output terminal can output passive switch contact signals.

[0007] As a further embodiment of the present invention, the remote communication device is equipped with dual RJ Ethernet ports and dual serial communication ports. Both RJ Ethernet ports are connected to the station control layer switch of the NCS monitoring system, and the dual serial communication ports are respectively connected to the two programmable PLCs one-to-one. The NCS monitoring system station control layer switch and the remote communication device, and the remote communication device and the programmable PLC have dual-redundant communication.

[0008] As a further aspect of the present invention, the programmable PLC's switch output terminal can be edited to output multiple passive switch contact signals. The passive switch contact signals output by the programmable PLC include normally open contact signals and normally closed contact signals, which can be directly supplied to the secondary protection, automation, remote transmission, or metering systems of the power system.

[0009] As a further aspect of the present invention, the downlink data of the network communication protocol output by the NCS monitoring system station control layer switch includes full basic information on the on / off status of power plant units, standby transformers, bus tie, bus branch and various disconnectors, unit operation combination mode and current transmission direction.

[0010] As a further aspect of the present invention, the protocol conversion of the remote communication device is performed in real time, ensuring data integrity during the conversion process without packet loss or error, and the converted serial communication port downlink data can be transmitted to the programmable PLC in real time.

[0011] This regeneration system is deployed based on the existing network architecture of the power system. It does not require technical modifications or replacements to the existing primary switches and disconnectors, nor does it require the addition of secondary cables for physical connections of switch and disconnector contacts. Furthermore, it does not require additional network security encryption devices or vertical isolation devices, thus meeting the relevant requirements for power system network security protection. The system is suitable for power plants that have been in operation for a long time and lack backup contacts, enabling the regeneration and acquisition of switch and disconnector status signals. It can also be adapted to the acquisition of switch and disconnector status signals in power system scenarios such as substations and power hubs. The passive switch contact signals output by the system can be extended to power system protection and control circuits, gate metering voltage switching logic discrimination circuits, and power system microcomputer anti-misoperation interlocking systems. It can also realize cross-network data transmission between the power system monitoring network and the company's local ERP office network and the remote group company's ERP office network.

[0012] Secondly, this invention provides a method for regenerating switch and disconnector status signals based on network data reuse, applicable to power system switch and disconnector status acquisition scenarios. It utilizes existing NCS monitoring system station control layer switches, remote communication devices, and at least two programmable PLCs in the power system. The method includes the following steps: S1. Data Acquisition: Through the existing NCS monitoring system station control layer switch of the power system, the downlink data of the network communication protocol output in the station control NCS network is collected in real time. The downlink data of the network communication protocol includes the original on / off status of power plant switches and disconnectors, unit operation mode, current transmission direction and basic information of circuit association between power plant units, standby transformers, bus tie and bus branch. S2. Protocol Conversion: The network communication protocol downlink data output by the NCS monitoring system station control layer switch is transmitted to the remote communication device. The remote communication device converts the network communication protocol downlink data into serial communication port downlink data adapted to the programmable PLC in real time. The conversion process ensures data integrity and eliminates packet loss and errors. S3. Logic discrimination: The converted serial communication port downlink data is transmitted to each programmable PLC. The programmable PLC calls the built-in switch logic discrimination algorithm and executes the PLC switch logic discrimination output based on the serial communication port downlink data. S4. Signal Regeneration Output: Based on the logic judgment result of step 3, the programmable PLC generates and outputs passive switch contact signals through its own switch output terminal to realize the regeneration of switch and disconnector status signals, which can be directly used by the power system secondary protection, automation, remote transmission or metering system.

[0013] As a further embodiment of the present invention, the remote communication device described in step 2 is equipped with dual RJ Ethernet ports and dual serial communication ports. The dual RJ Ethernet ports enable dual-redundant reception of downlink data in the network communication protocol with the station control layer switch of the NCS monitoring system. The dual serial communication ports enable dual-redundant transmission of downlink data in the serial communication port with two programmable PLCs, ensuring the stability and continuity of data transmission.

[0014] As a further embodiment of the present invention, the passive switch contact signal mentioned in step 4 is an editable configuration signal. The programmable PLC can output multiple passive switch contact signals including normally open contact signals and normally closed contact signals according to the usage requirements of the secondary side equipment of the power system, and each contact signal matches the actual state of the switch, disconnector and circuit path state one by one.

[0015] The method of this invention does not require technical modifications or replacements to existing primary switches and disconnectors in the power system, nor does it require the addition of secondary cables for physical connections of switch and disconnector contacts. It directly reuses network data from the existing NCS monitoring system of the power system to regenerate switch and disconnector status signals. This method relies on the existing network architecture of the power system, eliminating the need for additional network security encryption devices or vertical isolation devices. It meets the relevant requirements for power system network security protection based on existing network protection. The entire process from steps 1 to 4 is a real-time execution process, where the transmission delay of protocol conversion does not exceed a preset threshold, and the logic judgment of the programmable PLC is performed in millisecond-level real-time calculations, ensuring the synchronization of the regenerated switch and disconnector status signals with the actual status of the equipment. This method is suitable for the regeneration and acquisition of switch and disconnector status signals in power plants with long service life and no backup contacts, where the power plant includes multiple operating units and multiple standby transformers. The regenerated switch and disconnector status signals can also be extended to applications such as status determination in power system protection and control circuits, logic judgment for switching of metering voltage at control points, microcomputer-based anti-misoperation interlocking in power systems, and data forwarding between the power system monitoring system and the internal monitoring networks of office production groups and companies.

[0016] This invention provides a method and system for regenerating switch and disconnector status signals based on network data reuse. Addressing the industry pain points of power system upgrades and expansions where aging equipment lacks backup contacts and traditional acquisition methods require laying secondary cables, this invention leverages existing network architecture and equipment to regenerate and logically determine switch and disconnector status signals. Compared to existing technologies, it offers multiple advantages, including zero-cost equipment modification, significantly simplified construction procedures, flexible signal output adaptation, network security and compliance adaptation, accurate and real-time determination results, and a wide range of application scenarios. The advantages include: 1. This invention requires no technical modification or replacement of existing primary equipment in power plants, such as switches, disconnectors, generators, and standby transformers. It completely avoids the equipment procurement, construction, and dismantling costs associated with primary equipment modification and avoids economic losses caused by power plant production shutdowns and generator outages during equipment technical upgrades. It is suitable for low-cost upgrades of old equipment with long service life and no backup contacts, thus avoiding primary equipment technical upgrades and reducing hardware modification costs.

[0017] 2. This invention abandons the traditional method of physically connecting switch and disconnector contacts by laying secondary cables. It directly reuses network data from the existing NCS monitoring system of the power system to regenerate status signals, eliminating the need for any additional secondary cables. This completely eliminates the construction procedures such as cable procurement, on-site wiring, and connection debugging, significantly shortening the project implementation period and reducing the manpower and material costs of subsequent cable maintenance and fault repair. Multiple passive switch contact signals, including normally open and normally closed states, can be edited and generated through the programmable PLC's switch output terminals. These signals can be flexibly configured according to the contact requirements of different power system secondary protection, automation, remote transmission, and metering systems. The output contact signals accurately match the actual state of the switches and disconnectors and the circuit path state, eliminating the need for additional signal conversion equipment and exhibiting strong compatibility and adaptability.

[0018] 3. This invention relies on the existing network architecture of the power system for deployment and implementation. Without adding any new network security encryption devices or vertical isolation devices, it meets the relevant network security protection specifications of the power system, avoiding the procurement, deployment, and debugging costs of new security equipment. It also avoids compatibility issues between new security equipment and the existing network architecture, ensuring the security and compliance of network data transmission and processing. The remote communication device achieves real-time conversion of downlink data according to the network communication protocol, with no packet loss or errors during the conversion process, ensuring data integrity. The programmable PLC's built-in logic discrimination algorithm can achieve millisecond-level real-time calculations, and the regenerated status signals are highly synchronized with the actual status of the equipment. This provides accurate and real-time data sources for power system operation monitoring, protection control, and power metering, improving the reliability of power system automation control.

[0019] 5. This invention fully leverages the network data value of existing NCS monitoring systems in power systems, directly collecting and reusing downlink data from the station control layer switch, maximizing the utilization of existing equipment and data resources. It eliminates the need for additional data acquisition equipment, avoiding waste of equipment and data resources, and aligns with the power system's development needs for energy conservation, emission reduction, and efficiency improvement. The remote communication device is equipped with dual RJ Ethernet ports and dual serial communication ports, achieving dual-redundant connections with the NCS monitoring system's station control layer switch and programmable PLC, respectively. If one communication link fails during data transmission, the other can seamlessly take over, effectively avoiding data interruption and judgment failure caused by single-link failures. This ensures the stability and continuity of the entire signal regeneration system, meeting the stringent requirements of uninterrupted operation of the power system.

[0020] 6. The system of the present invention relies on the existing network architecture and the protocol conversion capability of remote communication devices to realize secure cross-network data transmission between the power monitoring network and the company's local ERP and remote group ERP office networks. No additional network security isolation equipment is required, which completely breaks down the data barriers between the power production side and the enterprise management side, and provides data support for the digital and intelligent management of enterprises.

[0021] These or other aspects of the invention will become more apparent from the following description of embodiments. It should be understood that the foregoing general description and the following detailed description are exemplary and explanatory only, and are not intended to limit the invention. Attached Figure Description

[0022] To more clearly illustrate the technical solutions in the embodiments of the present invention or related technologies, the accompanying drawings used in the description of the exemplary embodiments or related technologies will be briefly introduced below. The drawings are used to provide a further understanding of the present invention and constitute a part of the specification. They are used together with the embodiments of the present invention to explain the present invention and do not constitute a limitation thereof. In the drawings: Figure 1 This is a logical architecture diagram of a switch and disconnector status signal regeneration system based on network data reuse, according to an embodiment of the present invention.

[0023] Figure 2 This is a flowchart of a method for regenerating switch and disconnector status signals based on network data reuse, according to an embodiment of the present invention. Detailed Implementation

[0024] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0025] In some of the processes described in the specification, claims, and accompanying drawings of this invention, multiple operations appearing in a specific order are included. However, it should be clearly understood that these operations may not be executed in the order they appear herein, or may be executed in parallel. The operation numbers, such as 101, 102, etc., are merely used to distinguish different operations and do not themselves represent any execution order. Furthermore, these processes may include more or fewer operations, and these operations may be executed sequentially or in parallel. It should be noted that the descriptions such as "first," "second," etc., in this document are used to distinguish different messages, devices, modules, etc., and do not represent a sequential order, nor do they limit "first" and "second" to different types.

[0026] The technical solutions in the exemplary embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described exemplary embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0027] See Figures 1 to 2 As shown in the figure, the present invention provides a method and system for regenerating switch and disconnector status signals based on network data reuse. Taking a power plant power system as an actual application scenario, the scenario includes units #1-#5 and standby transformers #01-#03. The equipment has been in operation for a long time, there are no backup contacts, and there is a need to determine the actual demand for grid-connected and grid-disconnected electricity based on the current flow direction of the unit-standby transformer. Combining the power system automation industry standards, the system deployment, parameter configuration, algorithm debugging and method execution process of the present invention are described in detail.

[0028] The implementation prerequisites and equipment selection for the switch and disconnector status signal regeneration method and system based on network data reuse in this embodiment are as follows: 1. Implementation prerequisites: A power plant has deployed an NCS monitoring system (network control system), and the station control layer switch is operating normally and can stably output downlink data of network communication protocol including the status of switches, disconnectors, units, and start-up and standby transformers; the site has an industrial-grade equipment installation environment, power supply conditions, and standard communication cabling foundation.

[0029] 2. Equipment selection: Remote communication device: Two industrial-grade protocol conversion devices are selected to support bidirectional conversion between IEC60870-5-104 network protocol and IEC60870-5-101 serial port protocol. They are equipped with dual RJ45 Ethernet ports and dual RS485 serial communication ports to meet the requirements of industrial-grade anti-interference and 7×24-hour operation. Programmable PLC: Two industrial-grade programmable logic controllers are selected, which have multi-channel switch output, high-speed serial communication capability, support logic algorithm programming and real-time calculation, and the output end is a passive dry contact type, which can be directly connected to the power secondary system. Communication accessories: Shielded Ethernet cable and industrial-grade RS485 serial cable are selected to adapt to the strong electromagnetic environment of power plants and reduce data transmission interference.

[0030] The switch and disconnector status signal regeneration system based on network data reuse of the present invention consists of a station control layer switch of the power plant's existing NCS monitoring system, a remote communication device, and a programmable PLC. It adopts a dual-redundant communication design to avoid data interruption caused by single-link failure. The specific hardware deployment and connection steps are as follows: Step 1: Connecting the remote communication device to the NCS station control layer switch.

[0031] The RJ45 Ethernet ports of the two remote communication devices are connected to the idle gigabit network ports of the station control layer switch of the power plant's NCS monitoring system via shielded network cables to achieve dual-path physical connection; ensure that the communication link is kept away from the power plant's high-voltage equipment to reduce electromagnetic interference and ensure stable reception of downlink data according to the network communication protocol.

[0032] Step 2: Connecting the remote communication device to the programmable PLC.

[0033] The RS485 serial communication ports of the two remote communication devices are connected one-to-one with the serial communication modules of the two programmable PLCs via industrial-grade serial cables to form a dual data transmission link. The serial cables are shielded and grounded to prevent packet loss or error during data transmission.

[0034] Step 3: Connect the output terminals of the programmable PLC.

[0035] Connect the digital output terminals of the two programmable PLCs to the signal input terminals of the power plant's secondary protection, automation, remote transmission, and metering systems, respectively. The PLC output terminals are passive switch contacts, requiring no additional power supply, and directly match the contact signal reception requirements of the secondary system. The corresponding connection relationships of normally open and normally closed contacts can be configured according to requirements.

[0036] The switch and disconnector status signal regeneration system based on network data reuse of the present invention, after completing the physical hardware connection, configures the parameters of the remote communication device and programmable PLC to ensure communication compatibility and real-time data transmission between devices. The specific configuration steps are as follows: Step 1. Confirm NCS station control layer switch parameters.

[0037] Confirm the network segment, subnet mask, gateway, and other parameters of the NCS switch, and record the output port and transmission rate of the downlink data of the network communication protocol to ensure that the network parameters of the remote communication device are consistent with them.

[0038] Step 2. Configure the parameters of the remote communication device.

[0039] Network parameters: Configure the same network segment and subnet mask as the NCS switch, communication baud rate of 1000Mbps, transmission protocol of TCP / IP, and enable dual Ethernet port redundant receiving mode; Protocol conversion parameters: Set the input protocol to network communication protocol, the output protocol to serial communication protocol, enable real-time conversion mode, and the conversion delay ≤100ms; Serial port parameters: Set the serial communication baud rate to 9600bps, data bits to 8 bits, stop bits to 1 bit, and no parity. This is a perfect match for the serial port receiving parameters of the programmable PLC, and enables the dual serial port redundant output mode.

[0040] Step 3. Configure basic parameters of the programmable PLC.

[0041] Communication parameters: Configure the PLC serial port to receive parameters that match the protocol of the remote communication device, and enable the dual serial port synchronous receiving mode to ensure that the converted serial communication port downlink data can be obtained in real time. Output parameters: Configure the PLC switch output terminal as a passive dry contact output, set the level and response time of the output channel, allocate normally open and normally closed contact output channels according to the secondary system requirements, and reserve expansion channels to meet subsequent contact requirements.

[0042] During algorithm debugging and verification, simulation debugging is performed first: Simulated serial communication port downlink data is input into the PLC through PLC programming software, simulating various typical scenarios such as complete unit shutdown, single unit operation, and multi-unit combined operation. This verifies the consistency between the PLC logic judgment results and the preset results, debugging until the judgment accuracy reaches 100%. Then, actual machine integration debugging is performed: the PLC receives the actual network-converted serial communication port downlink data transmitted by the remote control communication device. The PLC judgment results are compared with the actual operating status of the power plant's field equipment, and the algorithm is fine-tuned to ensure a complete match between the judgment results and the actual state.

[0043] After completing system hardware deployment, parameter configuration, and algorithm debugging, the signal regeneration method of this invention enters a normalized automatic operation phase, requiring no manual intervention throughout the process. It achieves a real-time closed loop of data acquisition, protocol conversion, logic discrimination, and signal output. The specific execution steps of the switch and disconnector status signal regeneration method are as follows: Step 1: Real-time acquisition of downlink data according to network communication protocols.

[0044] The power plant's existing NCS monitoring system station control layer switch monitors and collects data on the operating status of units #1-#5, standby transformers #01-#03, all bus tie, bus branch, switch, and disconnector in real time. It continuously outputs downlink data in the network communication protocol, which includes equipment on / off status, unit operating mode, and current flow information. Two remote communication devices receive this data synchronously and without delay through dual Ethernet links, achieving redundant data acquisition.

[0045] Step 2: Real-time protocol conversion from network communication protocol downlink data to serial communication port downlink data.

[0046] The remote communication device performs millisecond-level real-time protocol conversion on the collected network communication protocol downlink data, strictly following the IEC60870-5 series protocol standards, converting it into serial communication port downlink data recognizable by the programmable PLC. During the conversion process, the integrity and timing of the data are guaranteed, with no packet loss or errors. After the conversion is completed, the serial communication port downlink data is transmitted in real time to two programmable PLCs through dual RS485 serial communication links. The two PLCs receive the data synchronously, ensuring that no data is lost.

[0047] Step 3: Logic judgment of switch and disconnector status.

[0048] After receiving downlink data from the serial communication port, the two programmable PLCs synchronously invoke their built-in switch / knife switch logic discrimination algorithm to perform high-speed real-time calculations. The specific discrimination process is as follows: Step 3.1 Data Filtering: Automatically remove irrelevant data such as outgoing lines, and extract core data related to the determination of power supply to the grid, including bus tie, bus branch, generator, standby transformer, switch, and disconnector. Step 3.2 Status Identification: Based on the extracted data, identify the on / off status of each switch and disconnector, the operating status of each unit, and the receiving end status of each standby transformer; Step 3.3 Path determination: Based on the circuit topology, determine the effective current path formation status between the positive power supply terminal (generator unit) and the negative power supply terminal (standby transformer).

[0049] Step 4: Passive switch contact signal regeneration output.

[0050] Based on the logic judgment result, the programmable PLC generates and outputs passive switch contact signals in real time through the digital output terminal, realizing the regeneration of switch and disconnector status signals. The core feature of this step is: (1) Multi-state contact output: According to the requirements of the power plant secondary system, the output switches and disconnectors can be edited to output multiple state contact signals such as normally open and normally closed. Each contact signal corresponds to the actual state of the field equipment. (2) Real-time synchronous update: When the operating status of the power plant equipment changes (such as unit start-up and shutdown, switch / disconnector opening and closing), the downlink data of the network communication protocol of the NCS monitoring system is updated in real time. After protocol conversion and logic judgment, the contact signals output by the PLC are switched synchronously to ensure that the signal is synchronized with the actual status of the equipment without delay. (3) Direct connection to secondary systems: The PLC outputs passive dry contact signals, which do not require additional signal conversion equipment and can be directly supplied to the power plant's secondary protection, automation, remote transmission and metering systems to meet the contact signal requirements of each system.

[0051] In this embodiment, the system realizes cross-network data transmission between the power monitoring network and a local ERP office network of a power plant and a remote ERP office network. The specific implementation steps are as follows: Configure cross-network data forwarding rules in the remote communication device, set the allowed switch signals to be transmitted, and prohibit the transmission of classified control commands; Configure the second Ethernet port of the remote communication device, connect it to the power plant office network switch, set up an independent network segment, and achieve logical data forwarding under physical isolation from the power monitoring network; For remote group ERP networks, the filtered production data is transmitted to the group data server through the VPN encrypted channel of the remote communication device, and the transmission process follows the power system network security specifications. The power plant and the group's ERP system can directly read the production data forwarded by the remote communication device, realizing automatic synchronization of production operation data and office management data without manual input.

[0052] The system of this invention is built upon existing power plant equipment, featuring a simple hardware architecture, low maintenance costs, and flexible expansion and adaptation to meet the needs of power plant renovations, expansions, and other power system scenarios. Routine maintenance includes: regularly checking the hardware operating status of the remote communication device and PLC to ensure fault-free equipment and stable power supply; checking the connectivity of communication links and regularly tightening the connectors of shielded network cables and serial cables to prevent poor contact; and eliminating the need for any maintenance operations on the power plant's primary switches and disconnectors, significantly reducing maintenance workload.

[0053] If the power plant's main wiring diagram or the rules for determining the unit's operating mode change, only the built-in logic discrimination algorithm needs to be modified through the PLC programming software; there is no need to redeploy the hardware. If the secondary system adds new contact signal requirements, only an output channel needs to be added to the PLC's digital output terminal, and the contact correspondence needs to be reconfigured, demonstrating strong scalability.

[0054] The method and system of this invention can be directly extended to other scenarios in the power system. Only local logic algorithm adjustments are needed according to scenario requirements, without changing the core hardware architecture and method execution flow. No technical modifications or replacements are required for existing primary switches and disconnectors, and no new secondary cables are needed, completely solving the problem of no backup contacts for old equipment. The real-time regeneration of switch and disconnector status signals is high, with an overall delay of ≤200ms from NCS data acquisition to PLC contact signal output, meeting the requirements of real-time monitoring for power system automation. The PLC can programmatically output 16 or more passive switch contact signals, including normally open and normally closed states, fully meeting the contact requirements of power plant secondary protection, automation, remote transmission, and metering systems. The system operates based on the existing network architecture of the power plant, without the need for additional network security encryption and vertical isolation devices, fully meeting the relevant requirements for power system network security protection. The system features a dual-redundant design, with no single point of failure in communication links and equipment, ensuring stable operation 24 / 7, and an equipment failure rate of ≤0.1%, improving the stability of power system operation.

[0055] It should be understood that although the above description follows a certain order, these steps are not necessarily executed in that order. Unless otherwise expressly stated herein, there is no strict order restriction on the execution of these steps, and they can be executed in other orders. Moreover, some steps in this embodiment may include multiple steps or multiple stages, which are not necessarily completed at the same time, but may be executed at different times. The execution order of these steps or stages is not necessarily sequential, but may be performed alternately or in turn with other steps or at least a portion of the steps or stages in other steps.

[0056] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A switch / disconnector status signal regeneration system based on network data reuse, characterized in that, This includes the existing NCS monitoring system station control layer switch, remote communication device, and at least two programmable PLCs that are connected in sequence. The NCS monitoring system station control layer switch is used to output downlink data of network communication protocol containing information on the original status of power plant switches and disconnectors, unit operation mode and current flow direction. The remote communication device is equipped with an RJ Ethernet port and a serial communication port. The RJ Ethernet port is connected to the station control layer switch of the NCS monitoring system. The remote communication device has a built-in protocol conversion module, which is used to convert the received network communication protocol downlink data into serial communication port downlink data and transmit it outward through the serial communication port. The programmable PLC is connected to the serial communication port of the remote communication device, and has a built-in switch and knife switch logic discrimination algorithm for receiving downlink data from the serial communication port and performing logic discrimination operations. The programmable PLC's switch output terminal can output passive switch contact signals.

2. The switch and disconnector status signal regeneration system based on network data reuse as described in claim 1, characterized in that, The remote communication device is equipped with dual RJ Ethernet ports and dual serial communication ports. Both RJ Ethernet ports are connected to the station control layer switch of the NCS monitoring system, and the dual serial communication ports are connected to the two programmable PLCs respectively. The NCS monitoring system station control layer switch and the remote communication device, as well as the remote communication device and the programmable PLC, have dual-redundant communication.

3. The switch and disconnector status signal regeneration system based on network data reuse as described in claim 1, characterized in that, The programmable PLC's digital output terminal can be edited to output multiple passive switch contact signals. The passive switch contact signals output by the programmable PLC include normally open contact signals and normally closed contact signals, which can be directly supplied to the power system's secondary protection, automation, remote transmission, or metering systems.

4. The switch and disconnector status signal regeneration system based on network data reuse as described in claim 1, characterized in that, The downlink data of the network communication protocol output by the NCS monitoring system station control layer switch includes full basic information on the on / off status of power plant units, standby transformers, bus tie, bus branch and various disconnect switches, unit operation combination mode and current transmission direction.

5. The switch and disconnector status signal regeneration system based on network data reuse as described in claim 4, characterized in that, The protocol of the remote communication device is converted to real-time conversion, and the converted serial communication port downlink data can be transmitted to the programmable PLC in real time.

6. A method for regenerating switch and disconnector status signals based on network data reuse, characterized in that, This method, applied to scenarios involving the acquisition of switch and disconnector status in power systems, utilizes existing NCS monitoring systems, station control layer switches, remote communication devices, and at least two programmable PLCs. The method includes the following steps: Data Acquisition: Through the existing NCS monitoring system station control layer switch of the power system, the downlink data of the network communication protocol output in the station control NCS network is collected in real time. The downlink data of the network communication protocol includes the original on / off status of power plant switches and disconnectors, unit operation mode, current transmission direction and basic information of circuit association between power plant units, standby transformers, bus tie and bus branch. Protocol conversion: The network communication protocol downlink data output by the NCS monitoring system station control layer switch is transmitted to the remote communication device. The remote communication device converts the network communication protocol downlink data into serial communication port downlink data adapted to the programmable PLC in real time. The conversion process ensures data integrity and eliminates packet loss and errors. Logical discrimination: The converted serial communication port downlink data is transmitted to each programmable PLC. The programmable PLC calls the built-in switch logic discrimination algorithm and performs PLC switch logic discrimination output based on the serial communication port downlink data. Signal regeneration output: Based on the logic judgment result of step 3, the programmable PLC generates and outputs passive switch contact signals through its own switch output terminal to realize the regeneration of switch and disconnector status signals, which can be directly used by the power system secondary protection, automation, remote transmission or metering system.

7. The method for regenerating switch and disconnector status signals based on network data reuse as described in claim 6, characterized in that, In the signal regeneration output, the passive switch contact signal is an editable configuration signal. The programmable PLC can output multiple passive switch contact signals, including normally open contact signals and normally closed contact signals, according to the usage requirements of the secondary side equipment of the power system. Each contact signal is matched one by one with the actual state of the switch, disconnector and circuit path state.

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