Nuclear power plant instrument control system, and its transformation method, device and storage medium

Abstract

The application provides a nuclear power plant instrument control system and a transformation method, device and storage medium thereof. The method upgrades the nuclear power plant instrument control system from an analog control system to a digital control system. In a process system interface layer, field signals are transformed to be collected by an input card of the digital control system, and control signal outputs are transformed to be outputs of a card of the digital control system. In an automatic control layer, a distributed control cabinet is transformed to be a control cabinet of the digital control system, and control logic is reconfigured by software configuration, which includes automatic redundancy voting and integration of cross-cabinet control functions. The nuclear power plant instrument control system after the transformation can greatly reduce the use of analog devices, effectively improve system safety, and reduce maintenance costs. Through interface adaptation of the digital control system, the system automation level can be effectively improved, system integration can be simplified, and the convenience of fault diagnosis and daily maintenance can be improved.

Description

Technical Field

[0001] This application relates to the field of nuclear power technology, and in particular to a nuclear power plant instrumentation and control system and its modification method, device and storage medium. Background Technology

[0002] Due to the extreme safety requirements, long lifespan, and huge investments in the nuclear power industry, some nuclear power plants still use the technical architecture of the 1970s for their instrumentation and control systems (I&C). The core components are mainly analog control devices and relay circuits, supplemented by a small number of programmable logic controllers (PLCs) and KIT / KPS monitoring systems based on the Solaris operating system.

[0003] As nuclear power units age, this technology system faces increasingly severe challenges in many aspects. The simulation equipment within the system ages rapidly over time, leading to more frequent failures and directly threatening the safe operation of the nuclear power plant. Spare parts for related simulation equipment are becoming increasingly difficult to supply due to production stoppages, increasing maintenance costs and technical support difficulties. The system maintenance process based on simulation technology is complex, time-consuming, and costly, making it difficult to meet the requirements of modern nuclear power plants for efficient operation and maintenance. The architecture and performance limitations of the simulation system restrict the room for further optimization of the instrumentation and control system in terms of control accuracy, automation level, and intelligent decision-making, affecting the overall operating efficiency of the power plant. In addition, the original system architecture is highly decentralized, lacking a unified digital platform for centralized management and coordination, which significantly increases the complexity of system integration, fault diagnosis, and daily maintenance. Summary of the Invention

[0004] In view of this, the present application provides a nuclear power plant instrumentation and control system and its modification method, device and storage medium, which aims to at least solve one of the problems existing in the prior art of nuclear power plant instrumentation and control systems, such as low safety, high maintenance cost and difficulty, low level of automation and system dispersion.

[0005] The first aspect of this application provides a method for modifying a nuclear power plant's instrumentation and control system, including: Upgrading the nuclear power plant's instrumentation and control system from an analog control system to a digital control system, wherein the digital control system includes a process system interface layer, an automation control layer, and an operation and information management layer; At the process system interface layer, the field signals acquired through analog signal distribution cards or relays are transformed into signals acquired through the input cards of the digital control system, and the control signals driven by relays or external power supplies are transformed into outputs of the digital control system cards. In the automation control layer, the distributed control cabinets based on relays or dedicated controllers are transformed into control cabinets of the digital control system. The control logic is reconfigured through software configuration, which includes automatic redundancy voting and cross-cabinet control function integration. In the operation and information management layer, the monitoring terminals of all subsystems in the nuclear power plant instrumentation and control system are transformed into standardized operator workstations with human-machine interfaces that run a unified digital control system.

[0006] In one possible implementation, the nuclear power plant instrumentation and control system includes a switch quantity processing system for the conventional island and a feedwater pump auxiliary system; Data is collected through the input card of the digital control system, including: Based on the signal source or the target location of the signal allocation, signal acquisition is performed using the corresponding isolation method. The transformation to digital control system card output includes: The method by which the digital control system drives the output signal is determined based on the level of the driving power supply of the output signal.

[0007] In one possible implementation, signal acquisition is performed using appropriate isolation methods based on the signal source or the target location of the signal allocation, including: For the switch signal from the conventional island, the first voltage of the query power supply is provided by the DC power supply system to directly query the switch signal; Signals from the nuclear island are isolated by relays and then collected or transmitted to the local actuator by the digital control system. For signals that need to be allocated to the nuclear island or a third-party system and do not need to be processed by the digital control system, the signals are allocated by relays, and the contact signals of the relays are collected by the digital control system. For signals that need to be distributed to different cabinets in the digital control system, isolation devices are used to distribute them to different cabinets, and the isolated signals are collected. For switch input signals that require external power supply, they are acquired after being isolated by an intermediate relay; The digital control system acquires manual control signals from the main control room for the turbine protection logic system.

[0008] In one possible implementation, determining the method by which the digital control system drives the output signal based on the driving power level of the output signal includes: The output signal, which is supplied with the first voltage by the switch quantity processing system of the conventional island, is modified to provide the first voltage to drive the output signal of the external device through the digital control system; For the switch output signal that is supplied with the second voltage by the switch processing system of the conventional island, it is modified to drive the intermediate relay with the first voltage of the switch output signal of the digital control system, and connect the power supply circuit of the second voltage through the contacts of the intermediate relay. For externally powered switch output signals, the external power supply remains unchanged. If the external voltage is the third voltage, the switch output signal of the digital control system drives the intermediate relay, and the contacts of the intermediate relay are connected to the external power supply circuit. If the external voltage is the fourth voltage and the signal is an automatic control signal, the switch output signal of the digital control system is connected to the automatic control signal circuit through interface optimization conversion. If the control signal is an enable or protection signal, the switch output signal of the digital control system drives the intermediate relay, and the contacts of the intermediate relay are connected to the external power supply circuit.

[0009] In one possible implementation, the method further includes: For the first and second devices used for redundancy design, the first and second devices are assigned to different cabinets; or, for the first and second functions used for redundancy design, the first function and the second function are assigned to different cabinets. For the three devices that are used in two locations and have one as a backup, they are configured in different racks, and the common area and one of the three devices are in the same rack. When multiple signals are sent to the local actuator, if the multiple signals do not include signals with redundant design, they are combined and output through the digital control system. For alarm signals of the highest importance, an alarm is generated in the control cabinet where the alarm logic is located, and then sent to the interface cabinet of the digital control system via hard-wiring between cabinets, and then to the alarm system interface. For alarm signals of the second highest importance, an alarm is sent to the interface cabinet of the digital control system via inter-cabinet communication, and then to the alarm system interface.

[0010] In one possible implementation, the nuclear power plant instrumentation and control system includes an analog signal processing system for the conventional island; Data is collected through the input card of the digital control system, including: Analog signals are acquired through analog input cards in a digital control system, and third-party signals are distributed through analog signal distribution cards. The transformation to digital control system card output includes: Analog signals are output through analog output cards of the digital control system, and after signal conversion through the digital control system cabinet, they are sent to indicators and recorders in the main control room.

[0011] In one possible implementation, the nuclear power plant instrumentation and control system includes a non-safety-grade instrumentation and control system for the nuclear island, and in the automation control layer, the method further includes: A feedforward circuit is added between the sewage flow controller and the flow setpoint, and the opening degree of the sewage flow control station is adjusted through the feedforward circuit. A digital automatic voting and selection module is introduced for redundant analog measurement signals to automatically eliminate invalid signals and select valid signal values ​​to participate in control when a single or multiple signal failure occurs. A gain correction stage is added to the critical signal channel. The hardware signal conversion and threshold comparison functions, which were originally implemented in independent signal processing racks, were migrated to the digital control system, and the similar processing racks that were originally scattered in multiple physical cabinets were physically integrated and centrally arranged. All signal allocation, logic operation and output modules involved in the same closed-loop control function implemented across different control subgroups are integrated and adjusted into the same control subgroup; The on-site signal compensation, which is achieved by a dedicated calibration rack, is directly acquired and processed by a digital control system; Some signals sent to the independent data acquisition system will no longer be transmitted via hardwire, but will be displayed at the operation layer of the digital control system or provided through data sharing with the digital control system.

[0012] In one possible implementation, within the operation and information management layer, the monitoring terminals of all subsystems in the nuclear power plant instrumentation and control system are transformed into standardized operator workstations with a human-machine interface running a unified digital control system, including: The system dynamically displays the status of the process system in a graphical manner and provides an interface for control commands to field equipment. Centralized display of key operating parameters for specific important equipment; The human-computer interface displays standard operating procedures, periodic tests, sequential control, intelligent decision support, and performance calculations. Provides dedicated views for inspection, power plant overview, daily and overhaul auxiliary monitoring, and scheduled safety status monitoring; The digital control system automatically generates information for displaying system logs, alarm lists, detailed drawings, and the status information of the digital control system itself.

[0013] A second aspect of this application provides a retrofitting device for a nuclear power plant instrumentation and control system, the device comprising: The digital upgrade unit is used to upgrade the instrumentation and control system of a nuclear power plant from an analog control system to a digital control system. The digital control system includes a process system interface layer, an automation control layer, and an operation and information management layer. The interface layer modification unit is used to modify the field signals acquired by the analog signal distribution card or relay at the interface layer of the process system to be acquired by the input card of the digital control system, and to modify the control signal output driven by the relay or external power supply to be output by the digital control system card. The control layer transformation unit is used to transform the distributed control cabinet based on relays or dedicated controllers into the control cabinet of the digital control system in the automation control layer, and to reconstruct the control logic through software configuration. The software configuration reconstruction includes automatic redundancy voting and cross-cabinet control function integration. The information management layer transformation unit is used to transform the monitoring terminals of all subsystems in the nuclear power plant instrumentation and control system into standardized operator workstations with human-machine interfaces that run a unified digital control system in the operation and information management layer.

[0014] A third aspect of this application provides a nuclear power plant instrumentation and control system, including a memory, a processor, and a computer program stored in the memory and executable on the nuclear power plant instrumentation and control system. When the processor executes the computer program, it implements the steps of the method for modifying the nuclear power plant instrumentation and control system provided in the first aspect.

[0015] A fourth aspect of this application provides a computer-readable storage medium storing a computer program that, when executed by a processor, implements the steps of the method for modifying the instrumentation and control system of a nuclear power plant provided in the first aspect.

[0016] The fifth aspect of this application provides a computer program product that, when run on a nuclear power plant instrumentation and control system, enables the nuclear power plant instrumentation and control system to implement the steps of the nuclear power plant instrumentation and control system modification method provided in the first aspect.

[0017] The nuclear power plant instrumentation and control system, its modification method, apparatus, and storage medium provided in this application have the following beneficial effects: By upgrading the nuclear power plant's instrumentation and control system from an analog control system to a digital control system, the following steps are taken: At the process system interface layer, field signals acquired by analog signal distribution cards or relays are transformed into input cards for the digital control system; control signals driven by relays or external power supplies are transformed into outputs from digital control system cards. At the automation control layer, the control logic is reconfigured through software configuration of the digital control system, enabling automatic redundancy voting and cross-cabinet control function integration. At the operation and information management layer, the monitoring terminals of all subsystems in the nuclear power plant's instrumentation and control system are transformed into standardized operator workstations with human-machine interfaces for the digital control system. This allows for the realization of operational functions in all subsystem control rooms and unified management of operational information from all subsystem control rooms. Because this method significantly reduces the use of analog devices in the nuclear power plant's instrumentation and control system, it effectively improves system safety, reduces maintenance costs, and, through interface adaptation with the digital control system, effectively enhances the system's automation level, simplifies system integration, and improves the convenience of fault diagnosis and daily maintenance. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of this application, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 This is a schematic diagram illustrating the implementation process of a method for modifying a nuclear power plant instrumentation and control system, as provided in an embodiment of this application.

[0020] Figure 2 This is a schematic diagram illustrating the implementation process of a signal acquisition method for a switch quantity processing system provided in an embodiment of this application.

[0021] Figure 3 This application provides a schematic diagram of a signal acquisition structure; Figure 4 This application provides a schematic diagram of a signal acquisition structure; Figure 5 This application provides a schematic diagram of a signal acquisition structure; Figure 6 This is a schematic diagram illustrating the implementation process of a signal output method for a switch quantity processing system provided in an embodiment of this application.

[0022] Figure 7 A schematic diagram illustrating the implementation process of an optimization and modification method for a non-safety-grade instrumentation and control system in a nuclear island, provided in an embodiment of this application; Figure 8A schematic diagram illustrating the implementation process of an optimization and modification method for a non-safety-grade instrumentation and control system in a nuclear island, provided in an embodiment of this application; Figure 9 This is a schematic diagram of the structure of a retrofit device for a nuclear power plant instrumentation and control system provided in an embodiment of this application.

[0023] Figure 10 This is a basic structural block diagram of a nuclear power plant instrumentation and control system provided in an embodiment of this application. Detailed Implementation

[0024] In the following description, specific details such as particular system architectures and techniques are set forth for illustrative purposes and not for limitation, in order to provide a thorough understanding of the embodiments of this application. However, those skilled in the art will understand that this application may also be implemented in other embodiments without these specific details. In other instances, detailed descriptions of well-known systems, devices, circuits, and methods are omitted so as not to obscure the description of this application with unnecessary detail.

[0025] It should be understood that, when used in this application specification and the appended claims, the term "comprising" indicates the presence of the described features, integrals, steps, operations, elements and / or components, but does not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components and / or a collection thereof.

[0026] It should also be understood that the term “and / or” as used in this application specification and the appended claims means any combination of one or more of the associated listed items and all possible combinations, and includes such combinations.

[0027] As used in this application specification and the appended claims, the term "if" may be interpreted, depending on the context, as "when," "once," "in response to determination," or "in response to detection." Similarly, the phrase "if determined" or "if detected [the described condition or event]" may be interpreted, depending on the context, as meaning "once determined," "in response to determination," "once detected [the described condition or event]," or "in response to detection [the described condition or event]."

[0028] Furthermore, in the description of this application and the appended claims, the terms "first," "second," "third," etc., are used only to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0029] References to "one embodiment" or "some embodiments" in this specification mean that one or more embodiments of this application include a specific feature, structure, or characteristic described in connection with that embodiment. Therefore, the phrases "in one embodiment," "in some embodiments," "in other embodiments," "in still other embodiments," etc., appearing in different parts of this specification do not necessarily refer to the same embodiment, but rather mean "one or more, but not all, embodiments," unless otherwise specifically emphasized. The terms "comprising," "including," "having," and variations thereof mean "including but not limited to," unless otherwise specifically emphasized. "A plurality" means "two or more."

[0030] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0031] Due to the extremely high safety requirements, long power plant lifecycles, and huge investments in the nuclear power industry, some nuclear power plants still use instrumentation and control systems (I&C) with a technological architecture dating back to the 1970s. Their core consists of analog control devices and relay circuits, supplemented only by a small number of programmable logic controllers (PLCs) and the KIT / KPS monitoring system based on the Solaris operating system.

[0032] As the units continue to operate, this traditional technology system faces increasingly prominent challenges at multiple levels.

[0033] Equipment aging and frequent failures: As the simulation equipment ages over time, the failure rate increases, directly threatening the safe and stable operation of the power plant. Difficulty in obtaining spare parts: As related simulation equipment gradually ceases production, obtaining spare parts becomes increasingly difficult, driving up maintenance costs and increasing the difficulty of technical support.

[0034] Complex and costly maintenance: The maintenance process of systems based on simulation technology is cumbersome, time-consuming, and costly, making it difficult to meet the needs of efficient operation and maintenance of modern power plants.

[0035] System performance limitations: The architecture and performance of the simulation system have bottlenecks, which restrict the further improvement of the instrumentation and control system in terms of control accuracy, automation level and intelligent decision-making, thus affecting the overall operating efficiency of the power plant.

[0036] System integration and management are complex: The original architecture was highly decentralized and lacked a unified digital platform for centralized management and coordination, which significantly increased the complexity of system integration, fault diagnosis and daily maintenance.

[0037] To address the aforementioned problems, this application proposes a method for retrofitting the instrumentation and control system of a nuclear power plant. Figure 1 This is a flowchart illustrating the implementation of a method for modifying a nuclear power plant instrumentation and control system, as provided in an embodiment of this application. Figure 1 As shown, the method includes: In S101, the nuclear power plant's instrumentation and control system is upgraded from an analog control system to a digital control system.

[0038] The digital control system (DCS) includes a process system interface layer, an automation control layer, and an operation and information management layer.

[0039] The process system interface layer is used to maintain the interface adaptation between the nuclear power plant's instruments and actuators and the digital control system, as well as the communication network of some local control cabinets.

[0040] The automation control layer is used for data processing, logic processing, protection and control calculations, and communication. Signals between control cabinets are optimized, merged, or adjusted according to function; important protection and control signals between control cabinets are hard-wired. The automation control layer in this embodiment uses a non-safety-grade instrumentation and control system with a redundant star network structure.

[0041] The operation and information management layer is used to maintain the original main operating methods of the main control room, make adaptive modifications to the interfaces, add computer terminals for monitoring and maintenance, and optimize the control functions so that the original operation of the main control room is not lost after optimization.

[0042] In S102, at the process system interface layer, the field signals acquired through the analog signal distribution card or relay are transformed into signals acquired through the input card of the digital control system, and the control signals driven by the relay or external power supply are transformed into outputs of the digital control system card.

[0043] The nuclear power plant instrumentation and control system used for retrofitting in this application embodiment includes the conventional island's switch processing system (KCO), conventional island's analog processing system (KRG), feedwater pump auxiliary system (APP), nuclear island control system (SIP V), thermocouple cold junction compensation system (KBS), and PLC control system. By digitally retrofitting these systems, the reliability, safety, and economy of the systems are improved, the human-machine interface is optimized, and the level of automation is enhanced.

[0044] When optimizing and upgrading the switch quantity processing system of the conventional island, the system mainly includes relays, which are used to complete the logic control of the main auxiliary systems and some electrical power switching systems. The KCO cabinets before the upgrade can be optimized into DCS control cabinets, power supply cabinets, and gateway cabinets. For example, before the upgrade, a nuclear power plant included 19 KCO cabinets; after the upgrade, it can be optimized into 15 DCS cabinets, 2 power supply cabinets, and 2 gateway cabinets.

[0045] When allocating KCO functions, the allocation principles include: The modified functions should maintain the current functional allocation as much as possible, so as to effectively reduce the laying of new cables.

[0046] In conjunction with the process system control, optimizations and adjustments are made based on the dispersed functional requirements of each cabinet. Equipment requiring separate or redundant configurations is adjusted according to the principle of cabinet proximity. That is, cabinets requiring separate or redundant configurations are placed as close as possible to each other or the distance between them is minimized.

[0047] When assigning KCO functions, rack-level signal allocation requirements include: For critical equipment that is used in two ways and has one as a backup, it can be allocated to three different racks (BAYs). For example, for three pumps in the CEX (condenser extraction system), the common parts can be placed in one of the racks.

[0048] For devices or functions that are divided into channels or columns, such as CH1 / 2 channels or A / B columns, they are assigned to two different cabinets. For example, the CEX006VL controls CH1 / 2 channels, assigning CH1 and CH2 to two cabinets. Similarly, the A and B columns of SN (enable signals) on the ABP301RE are assigned to two cabinets.

[0049] When assigning KCO functions, card-level signal assignment requirements include: The input / output signals for performing redundancy functions are distributed across different cards.

[0050] For important signals that perform the same function but have no redundancy relationship, if they cannot be assigned to the same link or the same cage due to limitations such as DCS card configuration, cabinet layout, and cable restrictions, then at least important signals that perform the same function should be assigned to different cards.

[0051] The input signals for the voting logic function (VOTER) are distributed across different data acquisition cards. For example, the three input signals for the 3-out-of-2 voting logic cannot be distributed across the same data acquisition card.

[0052] For redundant equipment in systems where the importance exceeds the predetermined requirements, priority should be given to allocating it to different links or chassis, such as the oil pump in the AGR system.

[0053] In this embodiment of the application, when the switch quantity processing system of a conventional island performs signal acquisition, the signal can be acquired through the corresponding isolation method according to the signal source or the target location of the signal allocation.

[0054] For example Figure 2 As shown, when a switch signal processing system acquires signals, it may include: In S201, for the switch signal from the conventional island, a query power supply with a first voltage is provided by the DC power supply system to directly query the switch signal.

[0055] Generally, for switch signals from the conventional island, a query voltage can be provided by the DC power supply system, such as a 48V DC voltage. When the switch is on, the DCS input card acquires the query voltage of that branch. When the switch is off, the DCS input card cannot acquire the query voltage of that branch.

[0056] In S202, signals from the nuclear island are isolated by relays and then acquired or transmitted to the local actuator by the digital control system.

[0057] For signals from the nuclear island, after the modification, they still need to be isolated by relays first, and then directly acquired by the DCS or sent to local actuators as needed. The isolation relays can continue to be powered by the original power system LCA or LCC. Protection and interlocking signals transmitted from the NI (nuclear island) to the CI (conventional island) (such as: ARE (feedwater system) feedwater isolation signal, ADG (feedwater deaerator system) / GCT (turbine bypass system) interlocking signal, etc.) do not need to be separately acquired and monitored by the DCS, maintaining the original relay expansion and avoiding the impact of DCS modification on the NI design.

[0058] The signal from the nuclear island is received by means of relay isolation, including the relay coil circuit, and the signal from the nuclear island is collected by the opening and closing of the contact circuit.

[0059] In S203, for signals that need to be allocated to the nuclear island or a third-party system and do not need to be processed by the digital control system, the signals are allocated by relays, and the contact signals of the relays are acquired by the digital control system.

[0060] For signals that need to be distributed to the nuclear island or other third parties and cannot be processed by the DCS, relays can still be used for distribution after the modification. The DCS can collect relay contact signals as needed, and the relay power supply can be provided by the DCS unless there are special requirements.

[0061] for example Figure 3In the signal acquisition diagram shown, for signals that need to be allocated to the core island NI and do not undergo processing by the digital control system, such as the switching signal of the core island switch GCT113VV, a query power supply is provided through the LCC, and the switch GCT113VV is connected in series to the coil circuit of the relay GCT003CB. When the normally open contact of GCT113VV closes, the contact of the relay GCT003CB is connected to the input channel of the DCS, thereby enabling the DCS to acquire the switching signal of the core island after isolation by the relay.

[0062] In S204, signals that need to be distributed to different cabinets of the digital control system are distributed to different cabinets through isolation devices, and the isolated signals are collected.

[0063] Signals that need to be distributed to different cabinets in the DCS, such as TPL (the code for manual control switches or buttons on the main control panel) manual control signals distributed to cabinets CH1 and CH2, are isolated by the DCS using diode isolation for dual-channel isolation, and the isolated dual-channel signals are acquired separately.

[0064] Among the possible implementations, such as Figure 4 In the signal acquisition diagram shown, external signals that need to be distributed to different cabinets of the digital control system are connected to the coil circuit of the relay after the query power is provided. Different isolation signals for different cabinets are generated through the different contacts of the relay. The DCS acquires the signals after relay isolation extension through different DI input channels (DCS DI input channel 1 and DCS DI input channel 2).

[0065] Among the possible implementations, such as Figure 5 In the signal acquisition diagram shown, external signals that need to be distributed to different cabinets of the digital control system are distributed to different cabinets through unidirectional diodes after the query power is provided. The signals distributed to different cabinets after being isolated by diodes are acquired through different DI input channels of DCS (DI input channel 1 and DI input channel 2 of DCS).

[0066] In S205, for switch input signals that require external power supply for querying, they are acquired after being isolated by an intermediate relay.

[0067] For the switch input signals (DI) that were originally powered by an external source, these signals mainly include pump and valve fault feedback signals, with the power sources being USER (125VDC) and USER (110VAC) respectively. After the digital upgrade, they can be isolated by an intermediate relay before being acquired.

[0068] In S206, the digital control system acquires manual control signals from the main control room for the turbine protection logic system.

[0069] For signals that were not originally acquired by the KCO system and were only supplied power or transferred by the KCO system, the solution after digital transformation can be: For instrument signals, the DCS should collect as many data as possible.

[0070] The DCS acquires manual control signals from the TPL (Turbine Protection Logic System) in the main control room.

[0071] The output optimization process of KCO can be described as follows: Figure 6 As shown, it includes: In S601, the output signal powered by the first voltage allocated by the switch quantity processing system of the conventional island is modified to provide the output signal of the external device through the first voltage provided by the digital control system.

[0072] For signals that were originally powered by the KCO (Knowledge Control Center) distributing the first voltage, after digital transformation, the DCS (Distributed Control System) can directly provide the first voltage, such as a 48V DC active switch output signal (DO) to drive external devices. For example, when the TPL (Time Limit of Power) of the main control room is inconsistent with the indicator light, the local electric motor relay 800XO / XF (relay model), the start / stop command of the 6.6kV pump, and the KSA (Alarm System) alarm signal can all be transformed into output signals that directly drive external devices through the DCS.

[0073] In S302, the switch output signal powered by the second voltage allocated by the switch processing system of the conventional island is modified to drive the intermediate relay through the first voltage of the switch output signal of the digital control system, and the power supply circuit of the second voltage is connected through the contacts of the intermediate relay.

[0074] For switching output signals (DO) that were originally supplied with a second voltage by the KCO, including those powered by 125VDC (LBM / LBJ) or 220VAC (LMC), such as solenoid valve control signals, after digital transformation: The first voltage of the DCS's digital output signal (DO), such as 48VDC, drives the intermediate relay. The second voltage is then connected in series through the intermediate relay contacts to power the device.

[0075] The power supply for the drive equipment can remain unchanged by the external power supply (DCS distribution), while power monitoring is retained.

[0076] In S603, for externally powered switch output signals, the external power supply remains unchanged. If the external voltage is a third voltage, the switch output signal of the digital control system drives an intermediate relay, and the contacts of the intermediate relay are connected to the external power supply circuit. If the external voltage is a fourth voltage and the signal is an automatic control signal, the switch output signal of the digital control system is connected to the automatic control signal circuit through interface optimization conversion. If the control signal is an enable or protection signal, the switch output signal of the digital control system drives an intermediate relay, and the contacts of the intermediate relay are connected to the external power supply circuit.

[0077] For the switch output signal (DO) that was originally powered externally, after digital transformation: The external power supply will remain unchanged. If the external power supply is a third voltage, such as powering USER (125VDC) (control signal for electric pump), the DCS's switch output signal (DO) can drive the intermediate relay, which is then connected in series with the external power supply circuit through the intermediate relay contacts.

[0078] If the external power supply is a fourth voltage, such as USER (110VAC) power supply (electric valve control signal), if the control signal is an automatic control signal, it can be optimized and converted into a DCS (48VDC) switch output signal (DO) and connected to the 800XO / 800XF (electric valve remote control command input interface) circuit of the electric valve through the interface optimization; if the control signal is an enable or protection signal, the DCS switch output signal (DO) can drive an intermediate relay, which is then connected in series with the external power supply circuit through the intermediate relay contacts.

[0079] In this application's embodiments, when optimizing and modifying the KCO, it may also include dual-channel control optimization, dual-use-one-standby equipment control optimization, actuator interface optimization, and alarm optimization, etc. For example... Figure 7 The schematic diagram of KCO optimization and modification shown includes: In S701, for the first device and the second device used for redundancy design, the first device and the second device are assigned to different cabinets, or for the first function and the second function used for redundancy design, the first function and the second function are assigned to different cabinets.

[0080] For the redundant first and second devices, including devices with separate channels CH1 / 2 (channels 1 and 2) and separate columns A / B (columns A and B), they are assigned to two different racks, and the relevant control logic is split into CH1 channel and CH2 channel. Similarly, for the redundant first and second functions, the first and second functions are assigned to different racks.

[0081] Common signals for devices or multiple device series controlled by dual CH1 / CH2 channels (such as ADG001SN (permission signal for feedwater deaerator system) used by both channels of CEX006VL (valve number of condenser extraction system), and CRF501SN (permission signal for circulating water system) in the control logic of CRF610 / 620PO (circulating water system number)) are sent to the control channels of the two cabinets through signal distribution, avoiding transfer from a single channel cabinet and ensuring the consistency of the response of the relevant logic channels.

[0082] For example, the control logic of AHP001 / 002VV (high-pressure heater system number) is split into CH1 / CH2 dual-channel logic, and the load shedding CH1 / CH2 signals are both involved in the control of AHP001VV and AHP002VV.

[0083] For example, the control logic of the deaerator extraction steam check valve ADG001VV (deaerator extraction steam check valve number) is split into CH1 and CH2 control logic.

[0084] In S702, three devices, one for use and one for backup, are configured in different racks, and the common part and one of the three devices are in the same rack.

[0085] For a dual-use, one-standby device, a total of three devices (two in operation and one on standby) are configured in three racks, with the common parts placed in one of the racks.

[0086] For example, the three pumps of the SRI (equipment cooling water system) are distributed to three cabinets. The common part can be placed in one cabinet with the control logic of one of the pumps, allowing the signal (SN) to be sent to the cabinets where the three pumps are located through signal distribution (one is split into three).

[0087] For example, in a CEX (steam extraction system), three pumps are distributed to three cabinets. The common part (including the enable signal logic) can be placed in one cabinet with the control logic of one of the pumps. The enable signal is sent to the cabinets where the other two pumps are located through the digital output signal DO.

[0088] In S703, when multiple signals are sent to the local actuator, if the multiple signals do not include signals with redundant design, they are combined and output by the digital control system.

[0089] In the original KCO system where multiple signals were sent to the local actuator, after digital transformation, signals with non-redundant designs (i.e., signals not in CH1 / CH2 or A / B columns) can be merged and output in the DCS logic. For signals with redundant designs, including signals in CH1 / CH2 and A / B columns, merging is not performed, and the multiple outputs remain unchanged.

[0090] In S704, for alarm signals of the first importance, an alarm is generated by the control cabinet where the alarm logic is located, and then sent to the interface cabinet of the digital control system via hard-wiring between cabinets, and then to the alarm system interface. For alarm signals of the second importance, an alarm is sent to the interface cabinet of the digital control system via inter-cabinet communication, and then to the alarm system interface.

[0091] For alarm signals sent to the KSA (alarm system), the original design was normally closed. After the modification, normally open contacts can be used while ensuring that the interface with the KSA remains unchanged (i.e., the logical meaning represented by the closed state of the KCO contacts acquired by the KSA remains unchanged). By changing the normal logic of the output points inside the DCS (using normally open output) and adjusting the output relay contact type (using normally open contacts) and the final wiring accordingly, it is possible to simulate the same external electrical behavior as the original design (normally closed contacts). This provides greater flexibility to the DCS design without modifying any settings or wiring definitions of the KSA system, and may simplify the configuration logic (alarms directly correspond to "output 1") or improve the security of the system's default state.

[0092] The alarm signals sent to KSA were previously generated in KRG200 / 201 / 202AR / APP001AR (rack number) or KCO's B rack, and then communicated with KSA via KCO's A rack. After the upgrade, the alarm signals are as follows: For critical alarm signals of the highest importance, the alarm signal is generated by the control cabinet where the alarm logic is located, and sent to the KCO interface cabinet through hard-wiring between cabinets. Then, it is sent to the KSA interface of the alarm system through the interface cabinet.

[0093] For non-critical alarm signals of the second level of importance, the signal generation cabinet sends them to the KCO interface cabinet via the inter-cabinet communication bus. The KCO interface cabinet generates a switch output signal (DO), which is then sent to the alarm system KSA interface through the interface cabinet.

[0094] For alarms from third-party systems, the interface report can be used to specify whether the signal should be transmitted via communication or hard-wired.

[0095] In a possible implementation, the DCS automatic command signal of the electric valve can be migrated in parallel to 800XF / 800XO (electric valve command interface), and the power supply type can be updated from the third or fourth voltage to the DCS system voltage.

[0096] If there is a TPL manual command signal from the main control room to the 800XF / 800XO, the DCS automatic command signal can be merged with the TPL manual command signal in the DCS logic and then sent to the 800XF / 800XO, but the protection and enable signals of the actuators will not be migrated.

[0097] The modification of the KCO system is basically the same as the modification of the feedwater pump auxiliary system APP.

[0098] In this embodiment of the application, the modification of the analog signal processing system KRG of the conventional island can be achieved by acquiring analog signals through the analog input card of the digital control system, distributing third-party signals through the analog signal distribution card, and outputting analog signals through the analog output card of the digital control system. After signal conversion through the digital control system cabinet, the signals are sent to the indicators and recorders in the main control room.

[0099] Before the upgrade, the conventional island KRG used CA cards (analog signal distribution cards) to acquire and distribute analog signals. After the digital upgrade, the original CA cards were eliminated, and the data was acquired by the DCS's AI cards (analog input cards).

[0100] For analog signals that need to be distributed to a third party and cannot be processed by a DCS, after digital transformation, signal distribution is carried out through an analog signal distribution card (CA card). This includes signals sent to systems such as GRE (Gurbine Regulation System), KKO (Gurbine Monitoring System), KDO (Data Display and Processing System), and KME (Performance Calculation and Efficiency Monitoring System).

[0101] For EU display signals that were originally only sent to the KIT (Power Plant Computer Information and Monitoring System), if the third-party cabinet and DCS already have a communication design, then the signals will be transmitted to the DCS via communication. Examples include local KRG (including CAR001AR), GRE / GSE / GME systems, etc.

[0102] For analog signals involved in control, the hardwire remains unchanged.

[0103] For analog signals that are used for both control and display, before the upgrade, they are first allocated by the CA card of KRG200AR and then sent to KRG201AR or KRG202AR. After the digital upgrade, they are transferred to the cabinet where the control logic is located for direct acquisition.

[0104] Regarding the optimization of analog signal output, the following are included: For signals sent to the main control ID and EN, after digital transformation, the DCS AO (analog output signal) outputs 4~20mA, and the signal is converted in the DCS cabinet (using the method of connecting resistors in parallel with terminal blocks) to convert the 4~20mA signal to 0.2V~1V and 100mV~500mV.

[0105] For signals sent from the local KRG (MX) to the main control ID (indicator) and EN (recorder), after digital transformation, the DCS does not need to be acquired by AI and then output by AO. The DCS is only responsible for switching and signal conversion.

[0106] For signals sent to KKO, DCS still needs to perform signal conversion; for signals sent to KME, due to the KME interface modification, DCS can directly send out 4-20mA signals without further conversion.

[0107] After the digital transformation, the local handheld controllers (RC) and their corresponding indicators (ID) are eliminated and replaced by software-based manual operation via the main control room operator station. Related settings can be configured at the DCS operator station. For cases where there were no local handheld controllers previously, the settings are now configured in the DCS configuration instead of the original RG (handheld controller) settings in the cabinet.

[0108] After digital transformation, analog signals are no longer sent to the main controller CEX030CC. Instead, the CEX025 / 026VL selection output is achieved in the DCS by collecting the switching selection status of the CEX030CC.

[0109] Signals from the conventional island KRG to or from the NI (nuclear island) and third-party cabinets, which originally had an isolation module (IS), can have their IS isolation module removed after digital transformation if both the sending and receiving platforms are NC (non-security grade) platforms.

[0110] Among the possible implementation methods, modifications to the feedwater pump auxiliary system include: The rack allocation is optimized, and the APP001AR BAY1 / 2 are combined to realize the protection of APA and ADG low liquid level (channel 1), the BAY3 / 4 are combined to realize the protection of APP1 and ADG low liquid level (channel 2), and the BAY5 / 6 are combined to realize the protection of APP2.

[0111] Card-level signal allocation requirements include: Input / output signals for performing redundancy functions should be distributed across different cards.

[0112] Important signals that perform the same function but have no redundancy should be assigned to different control links. If this requirement cannot be met due to DCS card configuration, cabinet layout, cable limitations, etc., they should at least be assigned to different cards.

[0113] The input signals for the voting logic function (“VOTER”) should be distributed across different data acquisition cards. For example, the three input signals for the 3-out-of-2 voting logic cannot be distributed across the same data acquisition card.

[0114] Redundant equipment in critical systems should be prioritized for allocation to different links, such as oil pumps in an AGR system. Based on system functional requirements, important signals can be assigned to the same link or the same card.

[0115] In S103, at the automation control layer, the distributed control cabinet based on relays or dedicated controllers is transformed into the control cabinet of the digital control system. The control logic is reconfigured through software configuration, which includes automatic redundancy voting and cross-cabinet control function integration.

[0116] The modifications to the automation control layer in this application include modifications to the control of the switching quantity processing system of the conventional island, the control of the analog quantity processing system of the conventional island, the control of the feedwater pump auxiliary system, the control of the non-safety level instrumentation and control system of the nuclear island, the modification of the thermocouple signal processing system, and the modification of the alarm system.

[0117] The optimization and modification of the non-safety-grade instrumentation and control system of the nuclear island in this application embodiment can be as follows: Figure 8 As shown, it includes: In S801, a feedforward link is added between the sewage flow controller and the flow setpoint, and the opening degree of the sewage flow control station is adjusted through the feedforward link.

[0118] The APG (Wastewater Flow Control System) can add a feedforward link between the wastewater flow controller (APG502RG) and the flow setpoint (APG501RC), using different wastewater flow setpoints based on the start / stop status of RPE029PO (wastewater pump number). This ensures that the step change in wastewater flow when RPE029PO starts or stops is offset by the introduced feedforward link, thereby maintaining the stability of the opening of the pressure reduction and flow control station APG013 / 014VL (wastewater valve number), and optimizing the pressure reduction and flow control of APG013 / 014VL.

[0119] In S802, a digital automatic voting and selection module is introduced for redundant analog measurement signals. This module is used to automatically eliminate invalid signals and select valid signal values ​​to participate in control when a single or multiple signal failures occur. A gain correction stage is added to the critical signal channels.

[0120] After the modification, the GRE (turbine regulating system) adds a new GRE022MP (turbine pressure transmitter model). The second smallest value obtained after VOTER processing of the GRE022MP and GREM023 / 024MP signals is used for steam generator level control and RGL (reactor control rod speed control system) rod speed control. After the modification, GRE022 / 024MP signals are isolated and distributed to the GCT (turbine bypass system), and after VOTER processing, are used for C7A / C7B signal logic.

[0121] By adding GRE022MP and employing VOTER processing, the number of CCM (critical components) devices was reduced, improving the reliability of the control system. When a signal from one of the GRE022 / 023 / 024MP fails, VOTER automatically discards that signal, and the remaining two input signals vote, taking the larger value as the control input signal. When two or more signals fail, the VOTER output retains the last valid value.

[0122] In addition, GD (gain) is added after the VOTER output of GRE022 / 023 / 024MP and after the GRE044MP signal respectively to facilitate the calibration of the turbine pressure transmitter.

[0123] In S803, the hardware signal conversion and threshold comparison functions implemented by independent signal processing racks are migrated to the digital control system, and similar processing racks that were originally scattered in multiple physical cabinets are physically integrated and centrally arranged.

[0124] The RCP (Reactor Coolant System) main pump vibration shaft displacement measurement signal processing rack (RCP004 / 005 / 006RK) is used to process signals from the field into 4-20mA signals. Before the upgrade, these were distributed in cabinets KRG111 / 121 / 131AR. After the upgrade, due to space limitations in the DCS cabinet, the three racks were moved to the wall-mounted cabinet RCP800AR in the same room. The main pump vibration high (H), high-high (HH), and shaft displacement high (H) threshold comparison functions are now implemented within the DCS.

[0125] After the modification, GD (gain) was added to the processing logic of the temperature signals of the RCP primary loop cold pipe section and hot pipe section: RCP035MT(Hot Leg), RCP032MT(Cold Leg), RCP050MT(Hot Leg), RCP047MT(Cold Leg), RCP062MT(Hot Leg) and RCP059MT(Cold Leg) to facilitate the calibration of the temperature sensors.

[0126] The primary loop average temperature (TAVG) and the primary loop cold-hot pipe section temperature difference (DELTA T), calculated from the primary loop cold and hot pipe section temperatures, were previously used by RCP401ZA / 401ZI / 402ZA to select the maximum and minimum values ​​before being sent to RGL / GCT / RCP for control. After the upgrade, RCP481VT / 483VT / 482VT respectively implement the original function of selecting the maximum / minimum value (ZA / ZI), improving the system's reliability.

[0127] In S804, all signal allocation, logic operation and output modules involved in the same closed-loop control function implemented across different control subgroups are integrated and adjusted into the same control subgroup.

[0128] Before the upgrade, the functions of RCP007 / 008 / 011MN signal allocation, reference level setpoint generation, and main control calculation for the pressure regulator level control were implemented in subgroup 4C, while the functions of RCV005 / 018MD signal allocation, threshold comparison, secondary control flow calculation, and valve control signal output (RCV046VP) were implemented in subgroup 2C. To avoid implementing the same function in two subgroups and reduce signal failure points, after the DCS upgrade, the functions of RCV005 / 018MD signal allocation, threshold comparison, secondary control flow calculation, and valve control signal output, which were originally implemented in subgroup 2C, were moved to subgroup 4C.

[0129] In S805, the field signal compensation implemented by the dedicated calibration rack is directly acquired and processed by the digital control system.

[0130] The SAR001RK (SAR001MD Corrector) and RAZ001RK (RAZ001MD / 001MP / 001MT Corrector) measurement or radiation monitoring systems are used to correct field signals and can directly perform signal acquisition and compensation calculations through DCS.

[0131] In S806, some signals sent to the independent data acquisition system are no longer transmitted via hardwire, but are displayed at the digital control system operation layer or provided through digital control system data sharing.

[0132] According to the KDO (Data Display and Processing System) signal optimization list, except for ASG001MC (Auxiliary Water Supply System Number) which sends KDO signals through an isolated distribution hardwire, other KDO signals have been cancelled and replaced with displays on the second floor or shared DCS data points.

[0133] This application embodiment can also provide cold junction compensation for thermocouples through KBS201AR and provide power and signal conversion for RTD detectors through KBS202AR. Furthermore, the INFI90 (PLC control system) function is set to remain independent, and the functions originally implemented by the two cabinets are merged into the KRG180AR cabinet.

[0134] In S104, at the operation and information management layer, the monitoring terminals of all subsystems in the nuclear power plant instrumentation and control system are transformed into standardized operator workstations with human-machine interfaces that run a unified digital control system.

[0135] In this embodiment of the application, when modifying the monitoring terminal through the operation and information management layer, it may include: The system dynamically displays the status of the process system in a graphical manner and provides a control command interface for field equipment. It can use system flow diagrams (P&ID) or electrical single-line diagrams as backgrounds and employ elements such as graphics, colors, values, and trend curves to display the operating status of the entire process system (such as the CEX condenser extraction system and APG blowdown system) in real time and dynamically.

[0136] This type of screen centrally displays key operating parameters for specific important equipment. Unlike flowcharts that show the entire system, these screens focus on in-depth monitoring of a single or a few critical devices. They present all the key parameters of these devices in a concentrated, high-density display on a single screen, allowing operators to quickly and comprehensively assess their health status and operational performance.

[0137] The user interface displays standard operating procedures, periodic tests, sequential control, intelligent decision support, and performance calculations. It integrates procedural and analytical tasks that previously existed in paper documents or standalone computer systems into a unified operating interface, including: Standard Operating Procedures: Electronic operating procedures that guide operators through complex operations and automatically verify conditions.

[0138] Regular testing: The online equipment testing interface can automatically record test data and timing.

[0139] Sequence control: A dedicated interface for performing complex interlocking operations.

[0140] Intelligent decision-making and auxiliary judgment: Based on rules or models, provide operators with operational suggestions or anomaly diagnosis support.

[0141] Performance Calculation: An economic monitoring interface for real-time calculation of the efficiency of power plants or key equipment.

[0142] Provides dedicated views for inspections, power plant overviews, routine and overhaul auxiliary monitoring, and scheduled safety condition monitoring. These screens serve the operator's daily monitoring, condition assessment, and specific tasks, rather than direct control. Information is organized from different dimensions, including: Inspection screen: Optimized parameter browsing path to improve inspection efficiency.

[0143] Power plant overview: Use a single image (such as a PT diagram or a plant status diagram) to summarize the overall operation mode and safety status of the power plant.

[0144] Routine / Overhaul Auxiliary Monitoring Screen: A set of important parameters customized for specific operating phases (such as routine power operation and unit overhaul).

[0145] T1 / T2 / T3 monitoring screens: monitoring views of key safety parameters under different safety conditions (such as normal operation and emergency operation).

[0146] The digital control system automatically generates displays for system logs, alarm lists, detailed drawings, and the system's own status information. This information does not originate directly from field sensors but rather from the DCS system itself. These are tools used for system maintenance, fault diagnosis, and operational logging, including: Alarm list: All current and historical alarms filtered by time and priority.

[0147] System Log: A record of all operations, events, and system messages.

[0148] Detailed drawings: A detailed configuration diagram of a specific measurement point or control logic that can be accessed.

[0149] DCS Status Screen: Displays the operating status and health of the DCS network, controllers, cards, and other hardware.

[0150] It is understood that the sequence number of each step in the above embodiments does not imply the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of this application.

[0151] Figure 9 This application provides a schematic diagram of a retrofit device for a nuclear power plant instrumentation and control system, which includes: The digital upgrade unit 901 is used to upgrade the nuclear power plant's instrumentation and control system from an analog control system to a digital control system. The digital control system includes a process system interface layer, an automation control layer, and an operation and information management layer. The interface layer modification unit 902 is used to modify the field signals acquired by the analog signal distribution card or relay to be acquired by the input card of the digital control system at the interface layer of the process system, and to modify the control signal output driven by the relay or external power supply to be output by the digital control system card. The control layer transformation unit 903 is used to transform the distributed control cabinet based on relays or dedicated controllers into the control cabinet of the digital control system in the automation control layer, and to reconstruct the control logic through software configuration. The software configuration reconstruction includes automatic redundancy voting and cross-cabinet control function integration. The information management layer transformation unit 904 is used to transform the monitoring terminals of all subsystems in the nuclear power plant instrumentation and control system into standardized operator workstations with human-machine interfaces that run a unified digital control system in the operation and information management layer.

[0152] Figure 9 The nuclear power plant instrumentation and control system modification device shown is related to... Figure 1 The method for modifying the instrumentation and control system of the nuclear power plant is shown.

[0153] In some embodiments of this application, please refer to Figure 10 , Figure 10 This is a basic structural block diagram of a nuclear power plant instrumentation and control system provided as an embodiment of this application. Figure 10 As shown, the nuclear power plant instrumentation and control system 10 of this embodiment includes: a processor 101, a memory 102, and a computer program 103 stored in the memory 102 and executable on the processor 101, such as a program for a method of modifying the nuclear power plant instrumentation and control system. When the processor 101 executes the computer program 103, it implements the steps in the various embodiments of the modification methods for the nuclear power plant instrumentation and control system described above. Please refer to the relevant descriptions in the embodiments for details, which will not be repeated here.

[0154] For example, the computer program 103 can be divided into one or more modules (units) for executing the various steps in the above method embodiments. The one or more modules are stored in the memory 102 and executed by the processor 101 to complete this application. The one or more modules can be a series of computer program instruction segments capable of performing specific functions, which describe the execution process of the computer program 103 in the nuclear power plant instrumentation and control system 10.

[0155] The nuclear power plant instrumentation and control system may include, but is not limited to, a processor 101 and a memory 102. Those skilled in the art will understand that... Figure 10 This is merely an example of the nuclear power plant instrumentation and control system 10 and does not constitute a limitation on the nuclear power plant instrumentation and control system 10. It may include more or fewer components than shown, or combine certain components, or different components. For example, the nuclear power plant instrumentation and control system may also include input / output devices, network access devices, buses, etc.

[0156] The processor 101 can be a Central Processing Unit (CPU), or other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. The general-purpose processor can be a microprocessor or any conventional processor.

[0157] The memory 102 can be an internal storage unit of the nuclear power plant instrumentation and control system 10, such as a hard disk or memory of the nuclear power plant instrumentation and control system 10. The memory 102 can also be an external storage device of the nuclear power plant instrumentation and control system 10, such as a plug-in hard disk, smart media card (SMC), secure digital (SD) card, flash card, etc., equipped on the nuclear power plant instrumentation and control system 10. Furthermore, the memory 102 can include both internal storage units and external storage devices of the nuclear power plant instrumentation and control system 10. The memory 102 is used to store the computer program and other programs and data required by the nuclear power plant instrumentation and control system. The memory 102 can also be used to temporarily store data that has been output or will be output.

[0158] It should be noted that the information interaction and execution process between the above-mentioned units are based on the same concept as the method embodiments of this application. For details on their specific functions and technical effects, please refer to the method embodiments section, which will not be repeated here.

[0159] This application also provides a computer-readable storage medium storing a computer program that, when executed by a processor, can implement the steps in the various method embodiments described above. In this embodiment, the computer-readable storage medium can be either non-volatile or volatile.

[0160] This application provides a computer program product that, when run on a mobile terminal, enables the mobile terminal to implement the steps described in the various method embodiments.

[0161] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the above-described division of functional units and modules is merely an example. In practical applications, the above functions can be assigned to different functional units and modules as needed, that is, the internal structure of the system can be divided into different functional units or modules to complete all or part of the functions described above. The functional units and modules in the embodiments can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit. Furthermore, the specific names of the functional units and modules are only for easy differentiation and are not intended to limit the scope of protection of this application. The specific working process of the above units and modules can be referred to the corresponding process in the foregoing method embodiments, and will not be repeated here.

[0162] If the integrated module / unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, all or part of the processes in the methods of the above embodiments can also be implemented by a computer program instructing related hardware. The computer program can be stored in a computer-readable storage medium, and when executed by a processor, it can implement the steps of the various method embodiments described above. The computer program includes computer program code, which can be in the form of source code, object code, executable files, or certain intermediate forms. The computer-readable medium can include: any entity or device capable of carrying the computer program code, recording media, USB flash drives, portable hard drives, magnetic disks, optical disks, computer memory, read-only memory (ROM), random access memory (RAM), electrical carrier signals, telecommunication signals, and software distribution media, etc. It should be noted that the content included in the computer-readable medium can be appropriately added or removed according to the requirements of legislation and patent practice in the jurisdiction. For example, in some jurisdictions, according to legislation and patent practice, computer-readable media do not include electrical carrier signals and telecommunication signals.

[0163] In the above embodiments, the descriptions of each embodiment have different focuses. For parts that are not described in detail or recorded in a certain embodiment, please refer to the relevant descriptions of other embodiments.

[0164] The above-described embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application, and should all be included within the protection scope of this application.

Claims

1. A method for retrofitting the instrumentation and control system of a nuclear power plant, characterized in that, The method includes: Upgrading the nuclear power plant's instrumentation and control system from an analog control system to a digital control system, wherein the digital control system includes a process system interface layer, an automation control layer, and an operation and information management layer; At the process system interface layer, the field signals acquired through analog signal distribution cards or relays are transformed into signals acquired through input cards of the digital control system, and the control signals driven by relays or external power supplies are transformed into outputs of digital control system cards. In the automation control layer, the distributed control cabinets based on relays or dedicated controllers are transformed into control cabinets of the digital control system. The control logic is reconfigured through software configuration, which includes automatic redundancy voting and cross-cabinet control function integration. In the operation and information management layer, the monitoring terminals of all subsystems in the nuclear power plant instrumentation and control system are transformed into standardized operator workstations with human-machine interfaces that run a unified digital control system.

2. The method according to claim 1, characterized in that, The nuclear power plant's instrumentation and control system includes a switch quantity processing system for the conventional island and a feedwater pump auxiliary system; Data is collected through the input card of the digital control system, including: Based on the signal source or the target location of the signal allocation, signal acquisition is performed using the corresponding isolation method. The transformation to digital control system card output includes: The method by which the digital control system drives the output signal is determined based on the level of the driving power supply of the output signal.

3. The method according to claim 2, characterized in that, Based on the signal source or the target location of the signal allocation, signal acquisition is performed using appropriate isolation methods, including: For the switch signal from the conventional island, the first voltage of the query power supply is provided by the DC power supply system to directly query the switch signal; Signals from the nuclear island are isolated by relays and then collected or transmitted to the local actuator by the digital control system. For signals that need to be allocated to the nuclear island or a third-party system and do not need to be processed by the digital control system, the signals are allocated by relays, and the contact signals of the relays are collected by the digital control system. For signals that need to be distributed to different cabinets in the digital control system, isolation devices are used to distribute them to different cabinets, and the isolated signals are collected. For switch input signals that require external power supply, they are acquired after being isolated by an intermediate relay; The digital control system acquires manual control signals from the main control room for the turbine protection logic system.

4. The method according to claim 2, characterized in that, Based on the driving power level of the output signal, the method by which the digital control system drives the output signal is determined, including: The output signal, which is supplied with the first voltage by the switch quantity processing system of the conventional island, is modified to provide the first voltage to drive the output signal of the external device through the digital control system; For the switch output signal that is supplied with the second voltage by the switch processing system of the conventional island, it is modified to drive the intermediate relay with the first voltage of the switch output signal of the digital control system, and connect the power supply circuit of the second voltage through the contacts of the intermediate relay. For externally powered switch output signals, the external power supply remains unchanged. If the external voltage is the third voltage, the switch output signal of the digital control system drives the intermediate relay, and the contacts of the intermediate relay are connected to the external power supply circuit. If the external voltage is the fourth voltage and the signal is an automatic control signal, the switch output signal of the digital control system is connected to the automatic control signal circuit through interface optimization conversion. If the control signal is an enable or protection signal, the switch output signal of the digital control system drives the intermediate relay, and the contacts of the intermediate relay are connected to the external power supply circuit.

5. The method according to claim 2, characterized in that, The method further includes: For the first and second devices used for redundancy design, the first and second devices are assigned to different cabinets; or, for the first and second functions used for redundancy design, the first function and the second function are assigned to different cabinets. For the three devices that are used in two locations and have one as a backup, they are configured in different racks, and the common area and one of the three devices are in the same rack. When multiple signals are sent to the local actuator, if the multiple signals do not include signals with redundant design, they are combined and output through the digital control system. For alarm signals of the highest importance, an alarm is generated in the control cabinet where the alarm logic is located, and then sent to the interface cabinet of the digital control system via hard-wiring between cabinets, and then to the alarm system interface. For alarm signals of the second highest importance, an alarm is sent to the interface cabinet of the digital control system via inter-cabinet communication, and then to the alarm system interface.

6. The method according to claim 1, characterized in that, The nuclear power plant's instrumentation and control system includes an analog signal processing system for the conventional island; Data is collected through the input card of the digital control system, including: Analog signals are acquired through analog input cards in a digital control system, and third-party signals are distributed through analog signal distribution cards. The transformation to digital control system card output includes: Analog signals are output through analog output cards of the digital control system, and after signal conversion through the digital control system cabinet, they are sent to indicators and recorders in the main control room.

7. The method according to claim 1, characterized in that, The nuclear power plant instrumentation and control system includes a non-safety-level instrumentation and control system for the nuclear island. In the automated control layer, the method further includes: A feedforward circuit is added between the sewage flow controller and the flow setpoint, and the opening degree of the sewage flow control station is adjusted through the feedforward circuit. A digital automatic voting and selection module is introduced for redundant analog measurement signals to automatically eliminate invalid signals and select valid signal values ​​to participate in control when a single or multiple signal failure occurs. A gain correction stage is added to the critical signal channel. The hardware signal conversion and threshold comparison functions, which were originally implemented in independent signal processing racks, were migrated to the digital control system, and the similar processing racks that were originally scattered in multiple physical cabinets were physically integrated and centrally arranged. All signal allocation, logic operation and output modules involved in the same closed-loop control function implemented across different control subgroups are integrated and adjusted into the same control subgroup; The on-site signal compensation, which is achieved by a dedicated calibration rack, is directly acquired and processed by a digital control system; Some signals sent to the independent data acquisition system will no longer be transmitted via hardwire, but will be displayed at the operation layer of the digital control system or provided through data sharing with the digital control system.

8. The method according to any one of claims 1-7, characterized in that, In the operation and information management layer, the monitoring terminals of all subsystems in the nuclear power plant instrumentation and control system are transformed into standardized operator workstations with a human-machine interface running a unified digital control system, including: The system dynamically displays the status of the process system in a graphical manner and provides an interface for control commands to field equipment. Centralized display of key operating parameters for specific important equipment; The human-computer interface displays standard operating procedures, periodic tests, sequential control, intelligent decision support, and performance calculations. Provides dedicated views for inspection, power plant overview, daily and overhaul auxiliary monitoring, and scheduled safety status monitoring; The digital control system automatically generates information for displaying system logs, alarm lists, detailed drawings, and the status information of the digital control system itself.

9. A retrofitting device for a nuclear power plant instrumentation and control system, characterized in that, The device includes: The digital upgrade unit is used to upgrade the instrumentation and control system of a nuclear power plant from an analog control system to a digital control system. The digital control system includes a process system interface layer, an automation control layer, and an operation and information management layer. The interface layer modification unit is used to modify the field signals acquired by analog signal distribution cards or relays to be acquired by input cards of digital control systems at the interface layer of the process system, and to modify the control signals driven by relays or external power supplies to be output by digital control system cards. The control layer transformation unit is used to transform the distributed control cabinet based on relays or dedicated controllers into the control cabinet of the digital control system in the automation control layer, and to reconstruct the control logic through software configuration. The software configuration reconstruction includes automatic redundancy voting and cross-cabinet control function integration. The information management layer transformation unit is used to transform the monitoring terminals of all subsystems in the nuclear power plant instrumentation and control system into standardized operator workstations with human-machine interfaces that run a unified digital control system in the operation and information management layer.

10. A nuclear power plant instrumentation and control system, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the computer program, it implements the steps of the method as described in any one of claims 1-8.

11. A computer-readable storage medium storing a computer program, characterized in that, When the computer program is executed by a processor, it implements the steps of the method as described in any one of claims 1-8.

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