A drive device for a control rod of a nuclear power plant

Abstract

This utility model discloses a drive device for control rods in nuclear power plants. The drive device includes a redundant controller, a first driver, a second driver, and a drive motor. The output terminal of the redundant controller is connected to the signal receiving terminals of the first and second drivers. The output terminals of the first driver and the redundant controller are also connected to the signal receiving terminals of the first and second drivers. The output terminals of both the first and second drivers are connected to the drive motor. In this drive device, active driver redundancy switching is achieved by redundantly setting the first and second drivers as primary and backup drivers. When the primary driver fails, the redundant controller can detect in real time and instruct the backup driver to seamlessly take over the drive task and output current to the drive motor, effectively eliminating a single driver failure point, significantly improving the fault tolerance and overall reliability of the drive device, and providing dual protection for core safety functions.

Description

Technical Field

[0001] This utility model relates to the field of nuclear power plant technology, specifically to a driving device for nuclear power plant control rods. Background Technology

[0002] In the operation of nuclear power plants, control rods (hereinafter referred to as control rods) are key safety and power regulation components. By inserting or removing control rods from the reactor core, they absorb neutrons, thereby dynamically regulating the nuclear reaction rate and controlling the reactor power.

[0003] The reliability of the control rod drive mechanism directly affects the continuity of control rod function and the stability of reactor operation. To meet the ever-increasing demands for high reliability and safety in nuclear power equipment, a more reliable drive mechanism is needed. Utility Model Content

[0004] In view of this, the present invention provides a driving device for control rods in nuclear power plants, which can improve the reliability of nuclear power plant operation.

[0005] In a first aspect, this utility model provides a drive device for control rods in a nuclear power plant, the drive device including a redundant controller, a first driver, a second driver, and a drive motor;

[0006] The output of the redundant controller is connected to the signal receiving terminals of the first driver and the second driver; the first driver and the second driver are each other's primary and backup drivers.

[0007] The output terminal of the first driver is connected to the drive motor, and the output terminal of the second driver is also connected to the drive motor.

[0008] The first driver is configured to output current to the drive motor according to the instruction of the redundant controller in the event of a failure of the second driver;

[0009] The second driver is configured to output current to the drive motor according to the instructions of the redundant controller in the event of a failure of the first driver.

[0010] In one possible implementation, the redundant controller includes at least a first controller and a second controller;

[0011] The output terminal of the first controller is connected to the signal receiving terminal of the first driver and the signal receiving terminal of the second driver;

[0012] The output terminal of the second controller is connected to the signal receiving terminal of the first driver and the signal receiving terminal of the second driver;

[0013] The first controller is configured to remain in standby mode when the second controller sends control signals to the first driver and the second driver;

[0014] The second controller is configured to remain in standby mode when the first controller sends control signals to the first driver and the second driver.

[0015] In one possible implementation, the drive motor is a dual-redundant winding motor;

[0016] The output terminal of the first driver is connected to the first coil winding, and the output terminal of the second driver is connected to the second coil winding; the first coil winding and the second coil winding are wound around the drive motor.

[0017] In one possible implementation, the driving device further includes a first filter and a second filter;

[0018] The first filter is connected between the first driver and the drive motor, and the second filter is connected between the second driver and the drive motor.

[0019] In one possible implementation, the first controller and the second controller are connected in communication.

[0020] In one possible implementation, the drive device further includes a control panel, which includes a switch for switching between local and remote control.

[0021] The output of the control panel is connected to the redundant controller.

[0022] In one possible implementation, the control panel further includes a display module and limit indicator lights;

[0023] The display module is used to display the position of the control stick;

[0024] The limit indicator light is used to indicate the status of the limit switch of the control rod.

[0025] In one possible implementation, the power input terminal of the drive unit is connected to an uninterruptible power supply via a shutdown circuit breaker.

[0026] In one possible implementation, the drive device further includes an air switch, a first power switch, and a second power switch;

[0027] The air switch is located at the power input terminal of the drive device, the first power switch is located at the power input terminal of the first driver, and the second power switch is located at the power input terminal of the second driver.

[0028] The air switch is used to control the power supply to the drive device.

[0029] The first power switch is used to control the power supply to the first driver.

[0030] The second power switch is used to control the power supply to the second driver.

[0031] In one possible implementation, the signal input terminal of the redundant controller is connected to the transmitter cabinet and the reactor control system;

[0032] The redundant controller is specifically configured to generate control signals based on sensor signals sent by the transmitter cabinet and control commands sent by the reactor control system.

[0033] This utility model provides a drive device for control rods in nuclear power plants. In this drive device, active drive redundancy switching is achieved by redundantly configuring a first and a second drive that act as both primary and backup drives. When the primary drive fails, the redundant controller can detect the failure in real time and instruct the backup drive to seamlessly take over the drive task, outputting current to the drive motor. This effectively eliminates a single drive failure point, significantly improving the fault tolerance and overall reliability of the drive device, and providing dual protection for core safety functions. Attached Figure Description

[0034] Figure 1 A schematic diagram of a driving device provided for an embodiment of this utility model;

[0035] Figure 2 A schematic diagram of another driving device provided in an embodiment of this utility model;

[0036] Figure 3 A schematic diagram of another driving device provided in an embodiment of the present utility model;

[0037] Figure 4 A schematic diagram of yet another driving device provided in an embodiment of this utility model;

[0038] Figure 5 A schematic diagram of a driving device provided for an embodiment of this utility model;

[0039] Figure 6 A schematic diagram of another driving device provided in an embodiment of this utility model;

[0040] Figure 7 This is a schematic diagram of another driving device provided in an embodiment of the present utility model. Detailed Implementation

[0041] The drive unit can control the insertion or extraction of control rods into or out of the reactor core via a drive motor. However, the complex environment of a nuclear power plant can easily cause drive unit failures, such as component failures or circuit abnormalities, which in turn can lead to fluctuations in the operation of the nuclear power plant.

[0042] To address this technical problem, this utility model provides a drive device for control rods in nuclear power plants. In this drive device, active drive redundancy switching is achieved by redundantly configuring a first and a second drive that act as both primary and backup drives. When the primary drive fails, the redundant controller can detect the failure in real time and instruct the backup drive to seamlessly take over the drive task, outputting current to the drive motor. This effectively eliminates a single drive failure point, significantly improving the fault tolerance and overall reliability of the drive device, and providing dual protection for core safety functions.

[0043] To make the above-mentioned objectives, features and advantages of this utility model more apparent and understandable, the embodiments of this utility model will be further described in detail below with reference to the accompanying drawings and specific implementation methods.

[0044] like Figure 1 As shown, Figure 1 This invention provides a drive device for a control rod in a nuclear power plant. The drive device includes a redundant controller, a first driver, a second driver, and a drive motor.

[0045] The output of the redundant controller is connected to the signal receivers of the first and second drivers. As an example, the output of the redundant controller can be connected to the signal receivers of the first and second drivers via a separate hard-wired channel. As another example, the output of the redundant controller can also be connected to the signal receivers of the first and second drivers wirelessly. The controller and drivers can communicate bidirectionally; in addition to sending control commands to the drivers, the controller can also receive status feedback from the drivers.

[0046] The output terminals of the first driver and the second driver are connected to the drive motor. Both drivers provide drive current to the drive motor. Upon receiving control signals from the redundant controller, both drivers can output drive current to the drive motor.

[0047] The first and second drives employ a primary-backup redundancy design. As one example, the first drive serves as the primary drive, and the second drive as the backup drive. As another example, the first drive serves as the backup drive, and the second drive serves as the primary drive.

[0048] The drive motor is used to convert electrical energy into mechanical torque, which drives the control rods through the transmission mechanism to perform actions such as lifting or inserting into the reactor core.

[0049] In normal operating mode, where both the first and second drivers can supply power to the drive motor, the redundant controller sends control signals to the primary driver (e.g., the first driver) and simultaneously to the standby driver (the second driver). The first driver outputs drive current to the drive motor, actuating the control rod. At this time, the second driver is in a standby state with zero current output, monitoring the status of the primary driver in real time but without output.

[0050] When the second driver detects a fault in the first driver (such as overcurrent, overtemperature, or communication interruption) and is unable to supply power to the drive motor, the second driver takes over from the first driver to output drive current to the drive motor, achieving seamless switching.

[0051] In one possible implementation, a communication connection is established between the first driver and the second driver. As an example, a status communication link (such as a digital bus or hardwired interlock signal) is set up between the first driver and the second driver, through which operational status information can be transmitted between them.

[0052] While the first driver outputs current to the drive motor under the instruction of the redundant controller, the second driver can determine that the first driver is in an active state and remains in standby mode. If the first driver malfunctions, it can send a signal to the second driver via a status communication link, allowing the second driver to confirm the malfunction and obtain the current control rod's motion parameters (such as speed and position). The second driver then takes over from the first driver to supply power to the drive motor, supporting the drive motor in controlling the control rod's movements.

[0053] As an example, the first and second drives are used to provide 380V AC power.

[0054] It should be noted that in this embodiment of the invention, both the first driver and the second driver supply power to the drive motor independently. Furthermore, this embodiment of the invention is described only as an example of a drive device including a first driver and a second driver, and does not limit the drive device provided in this embodiment to include only two drivers. Based on the drive device described in this embodiment of the invention, and considering the actual application scenarios of the drive device, those skilled in the art can redundantly set up a larger number of drivers. Multiple drivers are interconnected.

[0055] For example, the drive unit may include a third driver, a fourth driver, and a fifth driver, wherein the third driver, the fourth driver, and the fifth driver have the same function, all used to provide drive current to the drive motor. When the third driver, which is currently supplying power to the drive motor, fails and cannot provide power, the fourth driver and the fifth driver can communicate and negotiate to have one of the fourth driver or the fifth driver take over from the third driver to supply power to the drive motor.

[0056] In this embodiment of the utility model, the drive device is equipped with a first driver and a second driver that serve as primary and backup drivers, thereby achieving active driver redundancy switching. When the primary driver fails, the redundancy controller can detect and instruct the backup driver to seamlessly take over the drive task in real time and output current to the drive motor. This effectively eliminates the single driver failure point, greatly improves the fault tolerance and overall reliability of the drive device, and provides dual protection for the core safety functions.

[0057] In one possible implementation, such as Figure 2 As shown, the signal input terminal of the redundant controller is connected to the transmitter cabinet and the reactor control system.

[0058] The redundant controller is specifically configured to generate control signals based on sensor signals sent from the transmitter cabinet and control commands sent from the reactor control system.

[0059] In this embodiment of the invention, the redundant controller and the transmitter cabinet can be hardwired together, and the redundant controller and the reactor control system can also be hardwired together. The sensor signals sent by the transmitter cabinet are used to provide monitoring data such as control rod position, temperature, and vibration. When the drive unit operates in remote control mode, the reactor control system sends control commands to the redundant controller, which instruct the control rods to be raised or lowered.

[0060] In this embodiment of the invention, the redundant controller acts as the control center, receiving remote control commands and sensor signals from the reactor power control system. The redundant controller comprehensively analyzes the information to generate control commands, and simultaneously sends these commands to the first and second drivers to instruct either the first or second driver to output current to the drive motor.

[0061] To ensure reliable control of the control rods even in the event of reactor control system failure or maintenance, the drive unit can also operate in local control mode. In this embodiment of the invention, such as... Figure 3 As shown, the drive unit also includes a control panel.

[0062] The control panel includes a switch for switching between local and remote control. The outputs of the control panel are connected to redundant controllers.

[0063] The selector switch is used to switch the operating mode of the drive unit. In remote control mode, the drive unit's signals are routed to the reactor control system, and the redundant controller generates control signals for the drive unit based on the control commands from the reactor control system. In local control mode, the control panel's operating permissions are activated, and the redundant controller generates control signals for the drive unit based on the control commands from the control panel.

[0064] By setting up a control panel, technicians can freely switch the working mode of the drive device. Furthermore, the drive device provided in this embodiment of the invention can support multiple control modes to meet the diverse requirements of operation methods.

[0065] In one possible implementation, the control panel further includes a display module and limit indicator lights. The display module displays the position of the control rod; the limit indicator lights indicate the status of the limit switches of the control rod.

[0066] The display module can provide real-time visual feedback on the precise position of the control rods within the reactor core, offering operators a basis for decision-making. Limit switches can be set at the midpoint of the control rod's travel, acting as a physical stop at the end of the travel to prevent overdrive of the drive motor and damage to the transmission mechanism.

[0067] To further improve the reliability of the drive device, the drive device provided in this embodiment of the utility model, such as... Figure 4 As shown, the redundant controller includes at least a first controller and a second controller.

[0068] The output of the first controller is connected to the signal receiving terminals of the first and second drivers. The output of the second controller is also connected to the signal receiving terminals of both the first and second drivers.

[0069] The first controller is configured to remain in standby mode when the second controller sends control signals to the first and second drivers. The second controller is configured to remain in standby mode when the first controller sends control signals to the first and second drivers.

[0070] In this embodiment of the invention, the first controller and the second controller are independent hardware entities (e.g., using the same type of programmable logic controller), and the first controller and the second controller constitute a controller master-slave redundancy architecture. The first controller and the second controller have the same function, and the connection method of the first controller and the connection method of the second controller are the same. Both the first controller and the second controller can independently perform the functions implemented by the redundant controller in the above embodiment.

[0071] As an example, a first controller serves as the primary controller, while a second controller acts as a backup. The first controller generates control signals in real-time based on upper-level control commands and the position information of the control rods, and sends these signals to both the first and second drives. The second controller operates in hot standby mode, synchronously generating control signals in real-time based on upper-level control commands and the control rods' position information, but without outputting control signals to either the first or second drives. It should be noted that the logic for generating control signals is identical for both the first and second controllers; therefore, they can generate the same control signals based on the same data and information.

[0072] When the first controller malfunctions (e.g., program crashes or hardware failure), the second controller identifies the failure through mechanisms such as heartbeat detection. The second controller then takes over from the first controller, sending control signals to the first and second drivers to maintain the continuity of the control rod's operation. Data and state synchronization can be achieved between the first and second controllers in the drive unit.

[0073] In this embodiment of the invention, the drive device can ensure that only one controller is in signal output state at any given time through hardware interlocking or software arbitration mechanisms (for example, when the main controller outputs a control signal, the backup controller is forced to be in silent standby), thus avoiding conflict between the two controller commands.

[0074] In the above embodiments, the description only uses the example of a drive device including a first controller and a second controller, and does not limit the redundant controller in the drive device provided by this utility model embodiment to only include two controllers. Based on the drive device described in this utility model embodiment, and combined with the actual application scenario of the drive device, those skilled in the art can redundantly set more controllers. Multiple controllers are interconnected, and the connection method and function of each controller are the same.

[0075] In the driving device provided by this embodiment of the utility model, a first driver and a second driver can be configured to supply power to the drive motor. In one possible implementation, the drive motor in the driving device is a dual-redundant winding motor. The dual-redundant winding motor includes a first coil winding and a second coil winding.

[0076] The output of the first driver is connected to the first coil winding, and the output of the second driver is connected to the second coil winding. The first and second coil windings are wound together to drive the motor.

[0077] The first coil winding and the second coil winding are physically isolated and electromagnetically decoupled, which can block the fault transmission path between the drivers. Even if a single driver fails, the coil winding corresponding to the other driver can still operate safely.

[0078] It should be noted that when more drivers are redundantly configured in the drive unit, the drive motor can also be a multi-redundant winding motor. The number of coil windings in the drive motor can be the same as the number of drivers configured in the drive unit.

[0079] To further improve the reliability of the drive device, the drive device provided in this embodiment of the invention reduces electromagnetic interference from the driver to the drive motor by incorporating a filter circuit. For example... Figure 5 As shown, the driving device also includes a first filter circuit and a second filter circuit.

[0080] The first filter is connected between the first driver and the drive motor, and the second filter is connected between the second driver and the drive motor. Specifically, the first filter can be connected in series between the first driver and the first coil winding of the drive motor; the second filter can be connected in series between the second driver and the second coil winding of the drive motor.

[0081] As an example, the first and second filter circuits can be placed in separate metal shielded compartments within the junction box of the drive motor to avoid mutual inductive coupling. In this embodiment of the invention, by setting a filter circuit between the driver and the drive motor, the drive motor can be protected to a certain extent from the effects of voltage spikes.

[0082] In nuclear power plants, the stability of the power supply to the drive unit is also crucial. The drive unit provided in this embodiment can be powered by an uninterruptible power supply from the emergency power system.

[0083] like Figure 6 As shown, the power input terminal of the drive unit is connected to an uninterruptible power supply via a shutdown circuit breaker.

[0084] Uninterruptible power supplies (UPS) provide a continuous power supply to the drive unit, achieving zero power interruption and ensuring stable operation of the control rod safety system under any operating conditions. The shutdown circuit breaker, as the physical execution unit of the safety chain, forcibly disconnects the circuit in the event of a power failure or protection system triggering, blocking the transmission of abnormal electrical energy and ensuring the reliable execution of emergency shutdown commands. The shutdown circuit breaker and UPS work together to form a dual protection mechanism of continuous power supply and emergency isolation.

[0085] Furthermore, to improve the electrical safety of the drive device, the drive device also includes a first air switch, a first power switch, and a second power switch.

[0086] An air switch is located at the power input terminal of the drive unit, a first power switch is located at the power input terminal of the first driver, and a second power switch is located at the power input terminal of the second driver.

[0087] An air switch is used to control the on / off state of the power supply to a drive device.

[0088] The first power switch is used to control the power supply to the first driver.

[0089] The second power switch is used to control the power supply to the second driver.

[0090] As the main power isolation point for the drive unit, the air switch is directly connected to the uninterruptible power supply (UPS) output bus and undertakes the system-level emergency power outage function. When full-site maintenance, overall equipment overhaul, or handling extreme electrical faults are required, operating the air switch can physically disconnect all power supply circuits to the drive unit, achieving complete isolation from the upstream power source. As the main switch for the drive unit, when the air switch is open, it forcibly locks the first and second power switches, preventing the operation of downstream switches (first and second power switches) and effectively preventing the risks of live maintenance.

[0091] The first power switch is connected in series in the power supply branch of the first drive unit, providing fine-grained control capabilities at the equipment level. During redundant system operation, if the first drive unit experiences a winding short circuit, overload, or other fault, this switch can be independently disconnected to isolate the faulty unit, while ensuring that the second drive unit continues to receive uninterrupted power supply. This switch is equipped with hard-wired status feedback to the upper-level system, allowing operators to monitor the on / off position of the first power switch in real time. The opening operation of the first power switch does not affect other circuits, supporting online maintenance of the drive unit; that is, faulty drives can be replaced without reactor shutdown, significantly improving system availability.

[0092] The second power switch, serving as the dedicated control node for the second driver, functions identically to the first switching power supply but is physically independent, forming a parallel control structure with redundant channels. When the second driver needs to exit operation due to mechanical jamming or power malfunction, disconnecting the second power switch cuts off the current in that path while preserving the normal function of the first driver. The two-stage power switches (the first and second power switches) provide electrical isolation, ensuring zero electromagnetic interference leakage during single-sided operation and eliminating the possibility of common-cause failure at the hardware level.

[0093] It should be noted that the various embodiments in this specification are described in a progressive or parallel manner, with each embodiment focusing on its differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. Based on the driving device described in the above embodiments, this utility model also provides a schematic diagram of the driving device, as shown below. Figure 7 As shown, the drive device can achieve the functions and effects described in the above embodiments.

[0094] The above description of the disclosed embodiments enables those skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A drive device for control rods in a nuclear power plant, characterized in that, Includes a redundant controller, a first driver, a second driver, and a drive motor; The output of the redundant controller is connected to the signal receiving terminals of the first driver and the second driver; the first driver and the second driver are each other's primary and backup drivers. The output terminal of the first driver is connected to the drive motor, and the output terminal of the second driver is also connected to the drive motor. The first driver is configured to output current to the drive motor according to the instruction of the redundant controller in the event of a failure of the second driver; The second driver is configured to output current to the drive motor according to the instructions of the redundant controller in the event of a failure of the first driver.

2. The driving device according to claim 1, characterized in that, The redundant controller includes at least a first controller and a second controller; The output terminal of the first controller is connected to the signal receiving terminal of the first driver and the signal receiving terminal of the second driver; The output terminal of the second controller is connected to the signal receiving terminal of the first driver and the signal receiving terminal of the second driver; The first controller is configured to remain in standby mode when the second controller sends control signals to the first driver and the second driver; The second controller is configured to remain in standby mode when the first controller sends control signals to the first driver and the second driver.

3. The driving device according to claim 1, characterized in that, The drive motor is a dual redundant winding motor; The output terminal of the first driver is connected to the first coil winding, and the output terminal of the second driver is connected to the second coil winding; the first coil winding and the second coil winding are wound around the drive motor.

4. The driving device according to claim 1, characterized in that, The driving device further includes a first filter and a second filter; The first filter is connected between the first driver and the drive motor, and the second filter is connected between the second driver and the drive motor.

5. The driving device according to claim 1, characterized in that, A communication connection is established between the first driver and the second driver.

6. The driving device according to claim 1, characterized in that, The drive device also includes a control panel, which includes a switch for switching between local control and remote control. The output of the control panel is connected to the redundant controller.

7. The driving device according to claim 6, characterized in that, The control panel also includes a display module and limit indicator lights; The display module is used to display the position of the control stick; The limit indicator light is used to indicate the status of the limit switch of the control rod.

8. The driving device according to claim 1, characterized in that, The power input terminal of the drive unit is connected to an uninterruptible power supply via a shutdown circuit breaker.

9. The driving device according to claim 1, characterized in that, The drive device also includes an air switch, a first power switch, and a second power switch; The air switch is located at the power input terminal of the drive device, the first power switch is located at the power input terminal of the first driver, and the second power switch is located at the power input terminal of the second driver. The air switch is used to control the power supply to the drive device. The first power switch is used to control the power supply to the first driver. The second power switch is used to control the power supply to the second driver.

10. The driving device according to claim 1, characterized in that, The signal input terminal of the redundant controller is connected to the transmitter cabinet and the reactor control system; The redundant controller is specifically configured to generate control signals based on sensor signals sent by the transmitter cabinet and control commands sent by the reactor control system.

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