Electric energy automatic release method suitable for nuclear power station rod control power supply cabinet
By using a combination of threaded pins and threaded holes to identify the expected pull-out state of the plug-in, the system automatically cuts off external power supply to release stored energy, thus solving the safety hazards during the pull-out process of the rod control power cabinet plug-in in nuclear power plants and ensuring the safety of equipment and personnel.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- NUCLEAR POWER INSTITUTE OF CHINA
- Filing Date
- 2024-11-21
- Publication Date
- 2026-05-22
AI Technical Summary
During the process of removing the plugs from the rod control power cabinet of a nuclear power plant, existing technology cannot effectively release the internal electrical energy of the plugs, which poses a risk of equipment damage and personnel danger.
Design a combination structure of threaded pin and threaded hole, which uses the screw-in and screw-out states of the threaded pin to identify the expected pull-out state of the plug-in, and transmits signals through wires to automatically cut off the external power supply and release the internal energy stored in the plug-in.
It enables automatic release of electrical energy when the plug is removed, ensuring the safety of equipment and personnel, avoiding potential hazards caused by human error, and is easy to operate and widely applicable to rod control power equipment in nuclear power plants.
Smart Images
Figure CN122073157A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of pressurized water reactor nuclear power plant technology, specifically relating to an automatic power release method suitable for rod control power cabinets in nuclear power plants. Background Technology
[0002] Nuclear power plants use rod control power cabinets to provide power to the control rod drive mechanism, raising, lowering, or maintaining the axial position of the control rods in the reactor core for reactivity control. Rod control power cabinets typically employ a three-tiered design: cabinet-chassis-module. Modules provide the necessary power regulation, the chassis provides electrical connections between the cabinet and modules, and the cabinet provides equipment protection and external interface exchange. A rod control power cabinet module is a power regulation device that provides the required current to various coils in the control rod drive mechanism through its internal control circuitry; it also incorporates energy storage devices. During equipment maintenance, repair, or replacement, it is often necessary to remove the module. To ensure equipment and personnel safety, it is crucial to release the stored electrical energy within the module before removal to prevent accidental short circuits at the pins that could damage the equipment or cause harm to personnel due to accidental contact. Summary of the Invention
[0003] The purpose of this invention is to provide an automatic energy release method for rod control power cabinets in nuclear power plants, which enables automatic energy release of plugs when they are removed, thus ensuring equipment safety and personnel safety.
[0004] To achieve the above objectives, the technical solution adopted by the present invention is as follows:
[0005] An automatic power release method for a nuclear power plant rod control power cabinet includes a threaded pin on the front panel of the plug-in, and a threaded hole at a corresponding position on the chassis. The threaded pin is made of a conductor, and the threaded hole is divided into three parts: front, middle, and rear. The part closer to the threaded pin is the front part, the part further away from the threaded pin is the rear part, and the middle part is between the front and rear parts. The front and rear parts are made of conductors, and the middle part is made of insulators. When the threaded pin is loose or not tightened properly, the top of the threaded pin does not contact the rear part of the threaded hole, and the front and rear parts of the threaded hole are electrically disconnected. When the threaded pin is tightened properly, the threaded pin contacts the front and rear parts of the threaded hole, and the front and rear parts of the threaded hole are electrically connected through the threaded pin. When the front and rear parts of the threaded hole are in a disconnected state, it indicates that the plug-in is in the expected pull-out state. When in the connected state, it indicates that the plug-in is not in the expected pull-out state. A wire is used to short-circuit the front and rear portions of the threaded hole respectively, introducing this signal to the pin of the chassis connector connected to the plug-in. This introduces the expected pull-out state signal to the plug-in, enabling it to perform subsequent processing based on this signal. The plug-in is equipped with an external power supply on / off control circuit. When the plug-in does not receive a plug-in pull-out signal, the control circuit is in the external power supply connected state. When the plug-in receives a plug-in pull-out signal, the control circuit is in the external power supply disconnected state. When the plug-in receives the expected pull-out signal and disconnects the external power supply, it sends a command to its internal control circuit to provide current to the control rod drive mechanism coil. Since the external power supply has been disconnected, the energy for the plug-in to provide current to the drive mechanism comes from its internal energy storage, thus releasing the internal energy storage.
[0006] The functions of the plug-in threaded pin and the chassis threaded hole are twofold: first, to fasten the plug-in to the chassis, tightening the threaded pin after the plug-in is inserted into the chassis to prevent accidental plug-in removal; second, to generate a signal indicating that the plug-in is in the expected removal state.
[0007] The middle part of the surface is coated with an insulating material.
[0008] The threaded hole of the screw is used to fasten the plug. When the plug is inserted into the chassis and is running normally, the threaded hole of the screw is in a tightened state. If it is necessary to remove the plug, the screw must be loosened first. That is, the loosening of the screw indicates that the plug is expected to be removed.
[0009] For a single plug-in, one or more pairs of threaded pins and threaded holes are set according to requirements, and the expected pull-out status signal of the plug-in is introduced into the plug-in through the chassis and plug-in connector.
[0010] In the case where only one plug-in expected unplug status signal is set, this signal indicates that the plug-in is expected to be unplugged.
[0011] For situations where multiple plug-in expected unplug status signals are set, the expected unplug status can be represented by the presence of any one / two / n plug-in expected unplug status signals. Alternatively, it can be set so that the expected unplug status is represented only when all plug-in expected unplug status signals are present.
[0012] The energy stored in the plug-in can only support the current of the drive mechanism coil for less than 1 second, which is sufficient to completely release the electrical energy stored in the plug-in within the time it takes for the operator to loosen the threaded nail and pull out the plug-in.
[0013] Four sets of threaded pins are set on the front panel of the plug-in, and four sets of threaded holes are set on the corresponding chassis.
[0014] The beneficial effects achieved by this invention are as follows:
[0015] This invention targets rod control power cabinets. Through a plug-in fastening design, it generates a signal indicating anticipated plug-in removal. Upon this signal, external power is automatically cut off, and internal energy is released by supplying power to the drive mechanism coil, thus protecting both equipment and personnel safety. This design utilizes the inevitable operation during plug removal, eliminating the need for additional discharge procedures and avoiding the risk of incomplete discharge due to human error. This technology is easy to implement and can be widely applied to rod control power equipment in nuclear power plants, possessing a very broad market prospect. Attached Figure Description
[0016] Figure 1 This is a schematic diagram of the power cabinet chassis components;
[0017] Explanation: Taking the insertion of a plug-in into the chassis as an example, point A is a schematic diagram of the threaded hole of the threaded pin, which is used to generate the on / off signal of the expected pull-out state. B is the signal transmission wire, and C is the chassis connector (the plug-in achieves electrical connection and interface exchange with the chassis connector through the plug-in connector).
[0018] Figure 2 Schematic diagram of threaded hole design for threaded pin;
[0019] Explanation: Parts 1, 2, and 3 represent the front, middle, and rear sections, respectively. Parts 1 and 3 are conductive, while part 2 is non-conductive. As the threaded pin is screwed in, it sequentially contacts parts 1, 2, and 3. When the threaded pin is not in contact with part 3, parts 1 and 3 are insulated from each other and electrically disconnected. When the threaded pin contacts part 3, parts 1 and 3 are electrically connected through the threaded pin. This status signal can be transmitted via a wire. Detailed Implementation
[0020] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments.
[0021] Threaded locking and fixing device: Threaded pins are provided on the front panel of the plug-in, and threaded holes are provided at corresponding positions on the chassis. The plug-in threaded pins and chassis threaded holes mainly serve two functions: first, to secure the plug-in to the chassis; after the plug-in is inserted into the chassis, the threaded pins must be tightened to prevent accidental plug-in removal. The second function is to generate a signal indicating that the plug-in is in the expected removal state.
[0022] The design of the threaded pin and threaded hole, and the generation of the signal indicating that the plug is in the expected pull-out state: The threaded pin uses a conductor, and the threaded hole is divided into three parts: front, middle, and rear. The part closer to the threaded pin (i.e., closer to the front of the chassis) is called the front part, the part further away from the threaded pin (i.e., further away from the front of the chassis) is called the rear part, and the part in between is called the middle part. The front and rear parts use conductors, and the middle part uses an insulator (or has an insulating coating on its surface).
[0023] When the threaded pin is loose or not fully tightened, the tip of the threaded pin does not contact the rear part of the threaded hole, and the two parts of the threaded hole are electrically disconnected. When the threaded pin is fully tightened, it contacts both the front and rear parts of the threaded hole, and the two parts are electrically connected through the threaded pin. When the two parts of the threaded hole are disconnected, it indicates that the plug-in is in the expected pull-out state; when the two parts of the threaded hole are connected, it indicates that the plug-in is not in the expected pull-out state (i.e., in normal operation).
[0024] The threaded hole of the screw is used to fasten the plug. When the plug is inserted into the chassis and is running normally, the threaded hole of the screw should be in the tightened state. If it is necessary to remove the plug, the screw must be loosened first. That is, the loosening of the screw indicates that the plug is expected to be removed.
[0025] Expected pull-out signal transmission: Short-circuit the front and rear parts of the threaded hole with a wire to introduce the signal to the chassis connector pin connected to the plug-in, thereby introducing the expected pull-out status signal to the plug-in. This allows the plug-in to perform subsequent processing based on this signal.
[0026] Control Signal Synthesis: For a single plug-in, one or more pairs of threaded screw holes can be configured as needed, and the expected plug-in pull-out status signal can be introduced into the plug-in through the chassis and plug-in connector. When only one expected plug-in pull-out status signal is configured, this signal indicates that the plug-in is expected to be pulled out. When multiple expected plug-in pull-out status signals are configured, different signal synthesis methods can be used depending on actual needs. For example, it can be synthesized so that the presence of any one / two / n expected plug-in pull-out status signals indicates that the plug-in is expected to be pulled out; alternatively, it can be configured so that the presence of all expected plug-in pull-out status signals indicates that the plug-in is expected to be pulled out. Relatively speaking, the former is more likely to trigger the pull-out status for subsequent energy release control (ensuring energy release and guaranteeing equipment and personnel safety), while the latter is better able to avoid accidental subsequent energy release control caused by human error such as loosening screws.
[0027] External power supply cut-off control: The plug-in is equipped with an external power supply connection and disconnection control circuit. When the plug-in does not receive a plug-in removal signal, the control circuit is in the external power supply connected state; when the plug-in receives a plug-in removal signal, the control circuit is in the external power supply disconnected state. The purpose of this design is to cut off the subsequent supply of external energy in order to facilitate energy release.
[0028] Energy Release: When the plug receives the expected pull-out signal and disconnects the external power supply, it sends a command to its internal control circuit to provide current to the control rod drive mechanism coil. Since the external power supply has been disconnected, the energy source for the plug to provide current to the drive mechanism comes from its internal energy storage. Therefore, this design releases the internal energy stored in the plug. Under normal circumstances, the energy stored in the plug can only support the drive mechanism coil current for less than 1 second, which is sufficient to completely release the electrical energy stored in the plug within the time between the operator loosening the threaded pin and pulling out the plug.
[0029] Four sets of threaded pins are installed on the front panel of the plug-in, and four sets of threaded holes are provided on the corresponding chassis. Wires are soldered to parts 1 and 3 of the threaded holes respectively, and the wires are connected to the connector at the rear of the chassis, and then connected to the plug-in connector through the chassis connector. That is, the plug-in receives four on / off signals from the threaded holes (i.e., plug-in expected pull-out signals). When any two plug-in expected pull-out signals are present, the plug-in power supply is first cut off, and then the coil current "constant large" signal is triggered (i.e., the plug-in is required to output the large current required by the coil). At this time, the plug-in is in a state of providing a large current to the drive mechanism coil. Since the external power supply has been cut off, its energy source can only be provided by the plug-in's energy storage. The plug-in's stored energy can generally only support the coil current for less than 1 second. After that, the plug-in's stored energy is exhausted, the energy is completely released, and there is no longer any hazard to personnel safety or equipment safety.
[0030] This invention presents a design for predictive detection of plug-in removal behavior, and based on this, an automatic release design for the stored electrical energy inside the plug-in of the rod-controlled power cabinet, thereby ensuring equipment safety and personnel safety. An electrical linkage signal is set up for the mechanical action of separation and engagement between the plug-in and the chassis. The relative position between the threaded hole and the screw establishes the correlation between the mechanical action and the electrical linkage signal. The threaded hole adopts a three-section design of "conductive-insulating-conductive". The threaded screw achieves electrical connection between the two "conductive" sections of the three-section design of the threaded hole. The three-section design of the threaded hole achieves the correlation between the mechanical action and the electrical linkage signal. The three-section design of the threaded hole achieves electrical identification of the mechanical action of separation and engagement between the plug-in and the chassis. The conductive parts at both ends of the threaded hole achieve electrical identification of the mechanical action of separation and engagement between the plug-in and the chassis. The interconnection of the conductive parts at both ends of the threaded hole achieves electrical identification of the mechanical action of engagement between the plug-in and the chassis. The system uses two interconnected methods to achieve electrical identification of the mechanical action of separating the plug-in from the chassis. It utilizes the necessary operation of loosening screws before the plug-in is removed to identify the expected removal. It also utilizes the electrical disconnect between the two "conductive" sections of the three-segment threaded hole caused by the loosening of screws before removal to identify the expected removal. Finally, it utilizes the electrical connection between the two "conductive" sections of the three-segment threaded hole caused by tightening and loosening screws after the plug-in is in place to identify the placement (when the expected removal is no longer apparent). The on / off state of the threaded hole determines whether the plug-in is expected to be removed. A signal indicating expected removal is generated to cut off the plug-in's power supply. The disappearance of the expected removal signal powers the drive mechanism coil, releasing the stored energy inside the plug-in.
Claims
1. A method for automatic energy release in a nuclear power plant rod control power cabinet, characterized in that: A threaded pin is installed on the front panel of the plug-in, and a threaded hole is installed at the corresponding position on the chassis. The threaded pin is made of a conductor, and the threaded hole is divided into three parts: front, middle, and rear. The part closer to the threaded pin is the front part, the part farther away from the threaded pin is the rear part, and the middle part is between the front and rear parts. The front and rear parts are made of conductors, and the middle part is made of insulators. When the threaded pin is loose or not tightened properly, the top of the threaded pin does not contact the rear part of the threaded hole, and the front and rear parts of the threaded hole are electrically disconnected. When the threaded pin is tightened properly, the threaded pin contacts the front and rear parts of the threaded hole, and the front and rear parts of the threaded hole are electrically connected through the threaded pin. When the front and rear parts of the threaded hole are disconnected, it indicates that the plug-in is in the expected pull-out state. When the front and rear parts of the threaded hole are connected, it indicates that the plug-in is not in the expected pull-out state. By shorting the wires to the front and rear parts of the threaded hole respectively, the signal is introduced to the pin of the chassis connector connected to the plug-in, thereby introducing the expected pull-out status signal to the plug-in, so that the plug-in can perform subsequent processing based on the signal; the plug-in is equipped with an external power supply on / off control circuit. When the plug-in does not receive the plug-in pull-out signal, the control circuit is in the state of connecting the external power supply. When the plug receives the plug-in pull-out signal, the control circuit is in the state of cutting off the external power supply; when the plug receives the expected pull-out signal and cuts off the external power supply, it sends a command to its internal control circuit to provide current to the control rod drive mechanism coil. Since the external power supply has been cut off, the energy for the plug to provide current to the drive mechanism comes from its internal energy storage, so the internal energy storage of the plug is released.
2. The method for automatic power release applicable to the rod control power cabinet of a nuclear power plant according to claim 1, characterized in that: The functions of the plug-in threaded pin and the chassis threaded hole are twofold: firstly, to fasten the plug-in to the chassis, and secondly, to tighten the threaded pin after the plug-in is inserted into the chassis to prevent accidental plug-in removal. Secondly, it generates a signal indicating that the plug-in is in the expected unplugged state.
3. The method for automatic power release applicable to the rod control power cabinet of a nuclear power plant according to claim 1, characterized in that: The middle part of the surface is coated with an insulating material.
4. The method for automatic power release applicable to the rod control power cabinet of a nuclear power plant according to claim 1, characterized in that: The threaded hole of the screw is used to fasten the plug. When the plug is inserted into the chassis and is running normally, the threaded hole of the screw is in a tightened state. If it is necessary to remove the plug, the screw must be loosened first. That is, the loosening of the screw indicates that the plug is expected to be removed.
5. The method for automatic power release applicable to the rod control power cabinet of a nuclear power plant according to claim 1, characterized in that: For a single plug-in, one or more pairs of threaded pins and threaded holes are set according to requirements, and the expected pull-out status signal of the plug-in is introduced into the plug-in through the chassis and plug-in connector.
6. The method for automatic power release applicable to the rod control power cabinet of a nuclear power plant according to claim 5, characterized in that: In the case where only one plug-in expected unplug status signal is set, this signal indicates that the plug-in is expected to be unplugged.
7. The method for automatic power release applicable to the rod control power cabinet of a nuclear power plant according to claim 5, characterized in that: For situations where multiple plug-in expected unplug status signals are set, the expected unplug status can be represented by the presence of any one / two / n plug-in expected unplug status signals. Alternatively, it can be set so that the expected unplug status is represented only when all plug-in expected unplug status signals are present.
8. The method for automatic energy release applicable to the rod control power cabinet of a nuclear power plant according to claim 1, characterized in that: The energy stored in the plug-in can only support the current of the drive mechanism coil for less than 1 second, which is sufficient to completely release the electrical energy stored in the plug-in within the time it takes for the operator to loosen the threaded nail and pull out the plug-in.
9. The method for automatic energy release applicable to the rod control power cabinet of a nuclear power plant according to claim 1, characterized in that: Four sets of threaded pins are set on the front panel of the plug-in, and four sets of threaded holes are set on the corresponding chassis.