Emergency system

Abstract

The invention relates to the field of accident emergency treatment of small nuclear power plants, and provides an emergency system which is applied to a nuclear power plant, the nuclear power plant is provided with a plurality of nuclear reactors, and the emergency system in each nuclear reactor comprises an emergency generator, a power supply line and emergency electric equipment. At least one emergency generator is arranged, and the emergency generator can be a gasoline engine generator or a diesel engine generator. The power supply bus of the power supply circuit is connected with the emergency generator of the corresponding nuclear reactor; the emergency electric equipment is connected with the power supply line; wherein the power supply line is provided with an interface connected with other emergency generators of the nuclear reactor. In the scheme, the generators in a plurality of nuclear reactors can be mutually associated for use, so that the power supply capability of the diesel generator in the whole plant site can be improved, and the power supply continuity is ensured.

Description

Technical Field

[0001] The invention relates to the field of accident emergency treatment of small nuclear power plants, and in particular to an emergency system. Background Art

[0002] A nuclear power plant is a facility that provides external power or heat, but its normal operation requires support from various power sources. When a nuclear power plant loses external power supply, it needs diesel generators to provide power.

[0003] In the prior art, a large number of diesel generators need to be deployed, resulting in high construction costs for the generators. At the same time, the diesel generators need to be tested regularly, which requires a large amount of manpower and material resources, and a certain amount of electricity is wasted during the test process. Summary of the invention

[0004] In view of the above-mentioned shortcomings of the prior art, an object of the present invention is to provide an emergency system to reduce the construction and daily maintenance costs of the emergency system.

[0005] To achieve the above-mentioned purpose and other related purposes, the present invention provides an emergency system, which is applied to a nuclear power plant, wherein the nuclear power plant has a plurality of nuclear reactors, and the emergency system in each of the nuclear reactors comprises:

[0006] An emergency generator is provided with at least one;

[0007] A power supply line, wherein the power supply bus is connected to the emergency generator of the corresponding nuclear reactor;

[0008] Emergency electrical equipment connected to the power supply line;

[0009] The power supply line has an interface for connecting with emergency generators of other nuclear reactors.

[0010] In a specific embodiment of the present invention, it also includes a diesel pump for driving a medium-pressure fire water pump, the emergency power equipment includes a small fan arranged in the battery room, and the cold water unit of the nuclear reactor adopts passive heat dissipation after power failure.

[0011] In a specific embodiment of the present invention, the interface is connectable to a mobile generator.

[0012] In a specific embodiment of the present invention, the power supply line includes a distribution bus, and each of the emergency power equipment is connected to the distribution bus via a branch line to obtain power.

[0013] In a specific embodiment of the present invention, the distribution bus is connected to the normal power supply of the nuclear power plant.

[0014] In a specific embodiment of the present invention, the power supply line includes a power generation line for connecting the emergency generator and the distribution bus, and the power generation line is composed of a whole long cable.

[0015] In a specific embodiment of the present invention, the power supply line includes a power generation line for connecting the emergency generator and the distribution bus, the power generation line is composed of multiple cables connected by connectors, the connectors are arranged in a connector box, and the height of the connector box is higher than the height of the cable bodies on both sides.

[0016] In a specific embodiment of the present invention, the power generation line is installed overhead or in a cable trench.

[0017] In a specific embodiment of the present invention, the emergency generator is arranged in an independent factory building and is arranged separately from the distribution panel cabinet, and the independent factory building is arranged in a high terrain area.

[0018] In a specific embodiment of the present invention, two emergency generators are provided, and the two emergency generators are produced by different manufacturers.

[0019] The present invention proposes an emergency system. In the above scheme, the generators in multiple nuclear reactors can be used in conjunction with each other, which can improve the power supply capacity of the diesel generators in the entire plant site and ensure the continuity of power supply. Through this adjustment, the number and level of emergency generators can be reduced, and the capacity of diesel generators in the entire plant can be unified, thereby reducing construction and maintenance costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for describing the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying creative work.

[0021] Figure 1 It is a structural diagram of an emergency system in the prior art;

[0022] Figure 2 is a simplified structural diagram of an emergency system in one embodiment of the present invention;

[0023] Figure 3 Schematic diagram of the arrangement of street boxes in one embodiment of the present invention.

[0024] Explanation of the reference numerals: 10. Emergency generator; 20. Power supply line; 21. Interface; 22. Distribution bus; 23. Branch line; 24. Power generation line; 30. Emergency power equipment; 40. Junction box; 50. Normal power supply. DETAILED DESCRIPTION

[0025] The following describes the embodiments of the present invention by specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that the following embodiments and features in the embodiments can be combined with each other without conflict.

[0026] It should be noted that the illustrations provided in the following embodiments are only used to schematically illustrate the basic concept of the present invention, and thus the illustrations only show components related to the present invention rather than being drawn according to the number, shape and size of components in actual implementation. In actual implementation, the type, quantity and proportion of each component may be changed arbitrarily, and the component layout may also be more complicated.

[0027] Nuclear power plants of different sizes and with different technical routes have significant differences in power system configuration, especially in the positioning and configuration of diesel generators. In a certain project, each reactor is equipped with three emergency diesel generators (safety level, nuclear earthquake resistance, voltage of 10kV) and one SBO diesel generator (non-safety level with special requirements, nuclear earthquake resistance, voltage of 10kV); the whole plant is equipped with one medium-voltage mobile diesel generator (non-safety level, non-nuclear earthquake resistance, but must meet civil earthquake resistance requirements, voltage of 10kV) and one low-voltage mobile diesel generator (non-safety level, non-nuclear earthquake resistance, but must meet civil earthquake resistance requirements, voltage of 400V); in another project, each reactor is equipped with two standby diesel generators (non-safety level, perform investment protection function, nuclear earthquake resistance, voltage of 10kV) and two auxiliary diesel generators (non-safety level, non-nuclear earthquake resistance, voltage of 400V); the whole plant is equipped with one medium-voltage mobile diesel generator (non-safety level, must have a certain earthquake resistance, voltage of 10kV) and one low-voltage mobile diesel generator (non-safety level, must have a certain earthquake resistance, voltage of 400V). Some small nuclear power plants are also equipped with multiple diesel generators based on their own characteristics.

[0028] From the above content, it can be seen that in nuclear power plants with different technical solutions, diesel generator sets have different positioning and configuration. Small nuclear power plants with high inherent safety and relatively low power demand for operational safety have the conditions to simplify the configuration of diesel generator sets to minimize the project construction and operation costs.

[0029] like Figure 1As shown in the figure, taking the emergency power generation system of a small nuclear power plant as an example, each reactor is equipped with two backup diesel generators (non-safety level, voltage is 10kV) and one auxiliary diesel generator (non-safety level, 380V); the whole plant is equipped with mobile diesel generators (non-safety level, shared with diesel generators of other projects on the site, and additional mobile diesel generators are required when there are no relevant mobile facilities on the site). Among them, the backup diesel generator performs the function of in-depth defense, which is mainly used for investment protection, that is, under the LOOP condition (loss of external power supply), the diesel generator is started and loaded to minimize the demand for the use of passive safety facilities, so as to avoid irreversible situations in the nuclear power plant or damage to some important dedicated equipment due to triggering; the diesel generator is arranged in an independent diesel generator plant. The auxiliary diesel generator is mainly used at the end of battery discharge when the backup diesel generator is unavailable, and is used to continue to provide external power input for the nuclear power plant 72 hours after the accident; the diesel generator is arranged in the nuclear island or the auxiliary plant of the nuclear island. Mobile diesel generators are put into use when LOOP and the above-mentioned diesel engines are unavailable (for example, when an unexpected tsunami occurs, causing the relevant diesel engines to fail).

[0030] However, since it is equipped with multiple diesel generators, without considering the civil engineering costs and supporting systems of the relevant plant buildings, the cost of a single device is estimated to be about 50 million yuan. If the supporting costs such as civil engineering and multiple machine factors are taken into account, the cost will increase further. Diesel generators need to be tested regularly (monthly, quarterly and annually, etc.), which requires a lot of manpower and material costs, and will also cause a certain amount of electricity waste during the test process. Because multiple diesel generators are involved and there is a certain causal relationship between their inputs, the operating logic and coordination are relatively complicated, which leads to a large amount of manual judgment and operation required during the accident handling process.

[0031] To solve the above technical problems, Figure 2 As shown, the present invention provides an emergency system, which is applied to a nuclear power plant, specifically a small nuclear power plant, wherein the nuclear power plant has multiple nuclear reactors, and the emergency system in each of the nuclear reactors includes an emergency generator 10, a power supply line 20, and emergency power equipment 30. Small nuclear power plants usually have a high inherent safety, which is mainly reflected in the use of advanced safety technologies and systems in their design and operation, so that they can maintain a high level of safety in both normal operation and emergency situations. Due to the safety design of the small nuclear power plant itself, its dependence on the emergency generator 10 is relatively low, so the role of the emergency generator 10 is more focused on responding to unexpected disasters or long-term power supply needs in extreme situations.

[0032] At least one emergency generator 10 is provided, and the emergency generator 10 can be a gasoline generator or a diesel generator. Its main function is to provide stable power support in the event of a power system failure or other emergency situations, to ensure that key equipment of the small nuclear power plant can continue to operate, and to avoid system shutdown or accident escalation.

[0033] The power supply busbar of the power supply line 20 is connected to the emergency generator 10 of the corresponding nuclear reactor. It is used to transmit the power generated by the emergency generator 10 to the equipment and systems that need electricity. The design needs to ensure the reliability and anti-interference ability of the line to ensure stable power transmission in emergency situations.

[0034] The emergency power equipment 30 is connected to the power supply line 20. The emergency power equipment 30 includes UPS equipment (uninterruptible power supply equipment), small fans in the battery room, equipment related to personnel and equipment safety, and equipment that needs to be operated for a long time after an accident (such as post-accident status monitoring, lighting, communication, fire alarm, fire protection), etc.

[0035] Among them, the power supply line 20 has an interface 21 connected to the emergency generators 10 of other nuclear reactors. That is, a manual communication device is set between the nuclear reactor and each emergency generator 10 to improve the power supply capacity of the emergency generator 10 of the entire plant site and ensure the continuity of power supply. The manual communication device allows power to be obtained from the emergency generators 10 of other reactors when the emergency generator 10 of one reactor fails, thereby increasing the reliability of the overall power supply. The load of each generator can be adjusted according to demand to avoid overloading of a single generator and ensure that the working load of all emergency generators 10 is within a safe range. Through interconnection, power outages caused by failure of a single generator are reduced, and the overall stability of the system is improved. In an emergency, the emergency generator 10 can be quickly switched or connected manually to improve the ability to respond to emergencies.

[0036] In a specific embodiment of the present invention, a diesel pump for driving a medium-pressure fire water pump is also included, and the emergency power equipment 30 includes a small fan arranged in the battery room, and the chiller of the nuclear reactor adopts passive heat dissipation after power failure. By using a diesel pump to drive the medium-pressure fire water pump instead of an electric pump, the demand for the medium-pressure emergency generator 10 is reduced. The use of passive heat dissipation after the chiller is powered off ensures the temperature control of the main plant after LOOP, without relying on power supply, increasing the stability of the system, and also reducing the demand for the medium-voltage emergency generator 10. The small fan and low-voltage emergency generator 10 in the battery room are independently configured to supply power, ensuring that the regional ventilation needs are met and improving the flexibility and reliability of the system. The above working conditions require medium-voltage generators to supply power in the prior art. Through equipment replacement and load adjustment and distribution, the configuration of the medium-voltage emergency generator 10 is cancelled, and the capacity demand of the emergency generator 10 is effectively reduced. In this way, the power and voltage levels of the emergency generators 10 of the whole plant can be unified, and only one standby emergency generator 10 for the whole plant needs to be configured, which improves the efficiency of handling the failure of the emergency generator 10.

[0037] In a specific embodiment of the present invention, the interface 21 can be connected to a mobile generator. Combining the fixed emergency generator 10 with the mobile emergency generator 10 provides more processing methods without adding equipment. When a problem occurs with the fixed emergency generator 10, the mobile generator can be quickly connected as a substitute, which enhances the flexibility of emergency processing. Using existing mobile generators as alternatives eliminates the need to purchase new equipment, reducing costs. Combining fixed and mobile generators makes full use of existing resources and improves the efficiency of equipment use. Mobile generators can be used as an additional source of electricity to increase the redundancy of the system and ensure the continuity of power supply under various circumstances. Mobile generators can be quickly deployed where needed to ensure that emergency power generation needs are met in a timely manner.

[0038] like Figure 2As shown, the power supply line 20 includes a distribution bus 22, and each of the emergency power equipment 30 is connected to the distribution bus 22 through a branch line 23 to obtain power. The distribution bus 22 is set in the nuclear island plant as the main power transmission line to ensure that all emergency power equipment 30 are connected to the distribution bus 22 through the branch line 23, thereby providing power supply. Each emergency power equipment 30 obtains power from the distribution bus 22 through the branch line 23. This structure can make power distribution more flexible and efficient. The power of the emergency generator 10 is distributed by a dedicated switchboard. These switchboards distribute power to different MCCs (motor control centers) or distribution boxes according to load requirements. According to needs, several MCCs or distribution boxes are set on the distribution bus 22, and the MCCs or distribution boxes are arranged in the load concentration area, which reduces the cable length and reduces the loss in power transmission. By arranging the MCCs or distribution boxes in the load concentration area, the cable wiring is optimized and the cable length is shortened. This helps to improve power supply efficiency, reduce power loss, and simplify cable management. The relevant switchboards and distribution boxes should have a certain earthquake resistance. This is to ensure that the power system can continue to operate stably when natural disasters such as earthquakes occur, and to ensure the safety and reliability of small nuclear power plants.

[0039] The distribution bus 22 is connected to the normal power supply 50 of the small nuclear power plant. That is, the distribution bus 22 is the power supply line 20 in the normal state, and the normal power supply 50 refers to the power supply for the whole plant in the normal state. Directly connecting the distribution bus 22 to the normal power supply 50 avoids the installation of additional cables and distribution equipment, thereby saving wiring costs. Direct connection to the normal power supply 50 makes the distribution system structure simpler, reduces the complexity of the system and the difficulty of maintenance. It reduces unnecessary power conversion and distribution links, reduces potential failure points, and improves the stability of the system.

[0040] like Figure 2 As shown, the power supply line 20 includes a power generation line 24 for connecting the emergency generator 10 and the distribution bus 22, and the power generation line 24 is composed of a whole long cable. The design of the whole long cable avoids intermediate cable joints and reduces potential fault points. Cable joints are a common source of faults in power systems, and avoiding joints can significantly reduce the probability of faults. Cable connections without joints are usually more reliable because each joint may be a source of electrical faults, poor contact or insulation problems.

[0041] like Figure 3As shown, the power supply line 20 includes a power generation line 24 for connecting the emergency generator 10 and the distribution bus 22. The power generation line 24 is composed of multiple cables connected by joints. The joints are arranged in a joint box 40. The height of the joint box 40 is higher than the height of the cable bodies on both sides. When the power supply distance exceeds the manufacturing length of a single cable, the cable intermediate joint can be set in a higher terrain area, and the joint box 40 is set at a height higher than the cable body, which can effectively prevent short circuits at the joints due to flooding, thereby improving the reliability of the system. Preventing the intermediate joints from being corroded by water can effectively extend the service life of the cables and their joints.

[0042] In a specific embodiment of the present invention, the power generation line 24 is arranged overhead or in a cable trench. Overhead lines can be more conveniently inspected and maintained regularly, especially when a fault occurs, maintenance personnel can quickly reach the fault point for processing. The cable trench can effectively protect the cable from physical damage, such as construction, vehicle crushing, etc. The cable trench can prevent external factors (such as animal gnawing or human damage) from damaging the cable.

[0043] In a specific embodiment of the present invention, the emergency generator 10 is arranged in an independent factory building and is arranged separately from the power distribution cabinet, and the independent factory building is arranged in a high-altitude area. Selecting a high-altitude area to arrange the generator can significantly reduce the potential threat of floods or tsunamis to the equipment. This can prevent the generator from being submerged in water and ensure that it can continue to operate when a natural disaster occurs. The independent factory building needs to have a certain earthquake resistance, so that the emergency generator 10 can be protected from damage in the event of a vibration such as an earthquake. The earthquake-resistant design can enhance the structural stability of the factory building and ensure the normal operation of the generator after an earthquake.

[0044] In a specific embodiment of the present invention, two emergency generators 10 are provided, and a manual contact switch is provided between the emergency generators 10, and an interlocking device is provided to prevent different emergency generators 10 from running in parallel. Using two emergency generators 10 can improve the reliability and availability of the system. If one generator fails, the other generator can continue to supply power, thereby ensuring that the power supply is not interrupted. The interlocking device is to prevent the two emergency generators 10 from running at the same time and avoid the situation of parallel operation. Parallel operation may lead to uneven load distribution and may even cause equipment failure or electrical safety problems. The interlocking device can ensure that when one generator is running, the other generator will not automatically start or work. The two emergency generators 10 are manufactured by different manufacturers to avoid affecting the availability of power supply under common mode failure. Common mode failure refers to the failure of multiple devices at the same time due to the same design defect or production problem. By selecting generators from different manufacturers, this risk can be reduced and the overall reliability of the system can be improved. If a generator from one manufacturer fails due to a common problem, a generator produced by another manufacturer may not be affected, thereby ensuring the availability of power supply.

[0045] In summary, the present invention proposes an emergency system. In the above scheme, the generators in multiple nuclear reactors can be used in conjunction with each other, which can improve the power supply capacity of the diesel generators in the entire plant site and ensure power supply continuity. Through this adjustment, the number and level of emergency generators 10 can be reduced, and the capacity of emergency generators 10 in the entire plant can be unified, thereby reducing construction and maintenance costs.

[0046] The above embodiments are merely illustrative of the principles and effects of the present invention, and are not intended to limit the present invention. Anyone familiar with the art may modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by a person of ordinary skill in the art without departing from the spirit and technical concept disclosed by the present invention shall still be covered by the claims of the present invention.

[0047] In the description herein, many specific details, such as examples of components and / or methods, are provided to provide a complete understanding of embodiments of the present invention. However, those skilled in the art will recognize that embodiments of the present invention may be practiced without one or more of the specific details or with other devices, systems, components, methods, components, materials, parts, etc. In other cases, well-known structures, materials, or operations are not specifically shown or described in detail to avoid obscuring aspects of embodiments of the present invention.

[0048] References throughout this specification to "one embodiment," "an embodiment," or "a specific embodiment" mean that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the invention, and not necessarily in all embodiments. Thus, various appearances of the phrases "in one embodiment," "in an embodiment," or "in a specific embodiment" in different places throughout this specification do not necessarily refer to the same embodiment. In addition, the particular features, structures, or characteristics of any specific embodiment of the invention may be combined with one or more other embodiments in any suitable manner. It should be understood that other variations and modifications of the embodiments of the invention described and illustrated herein may be possible in light of the teachings herein and are to be considered part of the spirit and scope of the invention.

[0049] It should also be understood that one or more of the elements shown in the figures may also be implemented in a more separate or more integrated manner, or even removed because they are inoperable in certain circumstances or provided because they may be useful depending on the application.

[0050] In addition, unless otherwise explicitly indicated, any marking arrows in the drawings should be regarded as exemplary only and not limiting. In addition, unless otherwise indicated, the term "or" used herein is generally intended to mean "and / or". In the case where the term is not clear because it is anticipated that the ability to separate or combine is provided, the combination of components or steps will also be regarded as indicated.

[0051] As used in the description herein and throughout the claims that follow, "a", "an", and "the" include plural references unless otherwise indicated. Likewise, as used in the description herein and throughout the claims that follow, the meaning of "in" includes "in" and "on" unless otherwise indicated.

[0052] The above description of the illustrated embodiments of the present invention (including the contents described in the Abstract) is not intended to be an exhaustive list or to limit the present invention to the precise form disclosed herein. Although specific embodiments of the present invention and examples of the present invention are described herein for illustrative purposes only, various equivalent modifications are possible within the spirit and scope of the present invention as will be recognized and appreciated by those skilled in the art. As noted, these modifications may be made to the present invention in accordance with the above description of the embodiments described in the present invention, and these modifications will be within the spirit and scope of the present invention.

[0053] Systems and methods have been generally described herein as details that aid in understanding the present invention. In addition, various specific details have been given to provide an overall understanding of embodiments of the present invention. However, those skilled in the relevant art will recognize that embodiments of the present invention may be practiced without one or more of the specific details, or may be practiced using other devices, systems, accessories, methods, components, materials, parts, etc. In other cases, well-known structures, materials, and / or operations are not specifically shown or described in detail to avoid confusion with various aspects of embodiments of the present invention.

[0054] Thus, although the invention has been described herein with reference to specific embodiments thereof, freedom of modification, various changes and substitutions are also within the foregoing disclosure, and it should be understood that in some cases, some features of the invention will be employed without the corresponding use of other features without departing from the scope and spirit of the proposed invention. Thus, many modifications may be made to adapt a particular environment or material to the essential scope and spirit of the invention. The invention is not intended to be limited to the specific terms used in the claims below and / or the specific embodiments disclosed as the best mode contemplated for carrying out the invention, but the invention will include any and all embodiments and equivalents falling within the scope of the appended claims. Thus, the scope of the invention will be determined solely by the appended claims.

Claims

1. An emergency system, applied to a nuclear power plant, wherein the nuclear power plant has multiple nuclear reactors, characterized in that: The emergency system in each of the nuclear reactors includes: An emergency generator is provided with at least one; A power supply line, wherein the power supply bus is connected to the emergency generator of the corresponding nuclear reactor; Emergency electrical equipment connected to the power supply line; The power supply line has an interface for connecting with emergency generators of other nuclear reactors.

2. The emergency system according to claim 1, characterized in that: It also includes a diesel pump for driving a medium-pressure fire water pump. The emergency electrical equipment includes a small fan arranged in the battery room. The cold water unit of the nuclear reactor adopts passive heat dissipation after power failure.

3. The emergency system according to claim 1, characterized in that: The interface can be connected to a mobile generator.

4. The emergency system according to claim 1, characterized in that: The power supply line includes a distribution bus, and each of the emergency power equipment is connected to the distribution bus via a branch line to obtain power.

5. The emergency system according to claim 4, characterized in that: The power distribution bus is connected to the normal power supply of the nuclear power plant.

6. The emergency system according to claim 4, characterized in that: The power supply line comprises a power generation line for connecting the emergency generator and the distribution bus, and the power generation line is composed of a whole long cable.

7. The emergency system according to claim 4, characterized in that: The power supply line includes a power generation line for connecting the emergency generator and the distribution bus. The power generation line is composed of multiple cables connected by connectors. The connectors are arranged in a connector box. The height of the connector box is higher than the height of the cable bodies on both sides.

8. The emergency system according to claim 4, characterized in that: The power generation line is arranged overhead or in a cable trench.

9. The emergency system according to claim 1, characterized in that: The emergency generator is arranged in an independent factory building and is arranged separately from the distribution board cabinet. The independent factory building is arranged in a high-altitude area.

10. The emergency system according to claim 1, characterized in that: There are two emergency generators, and the two emergency generators are manufactured by different manufacturers.

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