A control rod drive mechanism capable of grouping and regulating power

Abstract

An embodiment of the present invention provides a control rod drive mechanism capable of grouping and regulating power, which relates to the technical field of nuclear power equipment. The control rod drive mechanism capable of grouping and regulating power includes a drive assembly, a transmission assembly, and a fuel assembly. The drive assembly includes a plurality of drive members, the transmission assembly includes a plurality of connecting members, a control rod is installed on the connecting member, and the fuel assembly is located at one end of the control rod away from the connecting member. The drive member is used to drive the connecting member to move along the axial direction of the control rod so that the control rod is inserted into or withdrawn from the fuel assembly. By driving the control rods on different connecting members with different drive members, it is possible to independently adjust the control rods in different regions of the corresponding fuel assembly, and the position of different control rods relative to the fuel assembly in their own axial directions can be adjusted respectively according to the actual reaction conditions above and below the fuel assembly, making full use of the fuel resources, that is, the fuel in the fuel assembly can be made to react relatively homogeneously.

Description

Technical Field

[0001] The present invention relates to the technical field of nuclear power equipment, and more specifically, to a control rod drive mechanism capable of grouped power regulation. Background Art

[0002] A nuclear reactor is a device used to control and utilize nuclear fission reactions. The main function of a nuclear reactor is to generate heat energy by controlling fission reactions and convert this heat energy into useful energy forms, such as electrical energy, heat energy, or other forms of energy. Nuclear reactors mainly include pressurized water reactors, boiling water reactors, heavy water reactors, etc. For pressurized water reactors, the drive assembly of the control rod is an important part of the pressurized water reactor, which drives the control rod through a through hole to perform lifting, lowering, holding, or fast insertion actions, controlling the startup and shutdown of the reactor and regulating the reaction power.

[0003] In some existing control rod drive mechanisms capable of grouped power regulation, after operation, it is easy to cause non-uniform fuel reactions in the fuel assembly. Summary of the Invention

[0004] An object of the present invention is to provide a control rod drive mechanism capable of grouped power regulation, which can achieve relatively uniform fuel reactions in the fuel assembly.

[0005] Embodiments of the present invention may be implemented as follows:

[0006] In a first aspect, the present invention provides a control rod drive mechanism capable of grouped power regulation, including:

[0007] A drive assembly, the drive assembly includes a plurality of drive members;

[0008] A transmission assembly, the transmission assembly includes a plurality of connecting members, a control rod is installed on the connecting member, and each connecting member is connected to a drive member;

[0009] A fuel assembly, the fuel assembly is located at one end of the control rod away from the connecting member;

[0010] Wherein, the drive member is used to drive the connecting member to move along the axial direction of the control rod, so that the control rod is inserted into or pulled out of the fuel assembly.

[0011] In an optional embodiment, the drive member includes a transmission gear and a drive structure, and the drive structure is used to drive the transmission gear to rotate;

[0012] The transmission assembly further includes a plurality of transmission racks, the transmission rack includes an assembly surface, and a plurality of meshing teeth extending along the axial direction of the control rod are arranged on the assembly surface and the meshing teeth mesh with the transmission gear. Each drive member is in transmission connection with a transmission rack through the transmission gear. One end of the transmission rack is connected to the connecting member, and the number of the transmission racks, drive members, and connecting members is the same.

[0013] In an alternative embodiment, the number of transmission racks is two and the two transmission racks are movably connected. The transmission racks are triangular prism-shaped. The outer peripheral surface of the transmission rack includes two adjacent fitting surfaces and a fitting surface located between the two fitting surfaces. The fitting surfaces of the two transmission racks face each other and can move relative to each other in the axial direction of the control rod.

[0014] In an alternative embodiment, the four fitting surfaces on the two transmission racks are sequentially connected at an angle, and any two adjacent fitting surfaces are arranged at a 90-degree angle.

[0015] In an alternative embodiment, the two driving members are respectively a first driving member and a second driving member. The first driving member includes a first transmission gear and a second transmission gear. The second driving member includes a third transmission gear and a fourth transmission gear. The first transmission gear and the second transmission gear are respectively meshed with the meshing teeth on the two fitting surfaces of one of the transmission racks, and the third transmission gear and the fourth transmission gear are respectively meshed with the meshing teeth on the two fitting surfaces of the other transmission rack.

[0016] In an alternative embodiment, the driving assembly further includes a driving block. The driving block is provided with a fitting hole. The inner wall of the fitting hole is provided with a fitting groove for installing the transmission gear. The two transmission racks pass through the fitting hole, and each transmission gear can rotate relative to the driving block around its own axis, and the transmission gears are all exposed outside the fitting hole.

[0017] In an alternative embodiment, the number of driving blocks is two and the two driving blocks are arranged in sequence along the axial direction of the control rod. The two driving blocks are respectively a first driving block and a second driving block. The fitting hole of the first driving block is provided with first fitting grooves on both sides in the first direction. The first transmission gear and the third transmission gear are respectively installed in the two first fitting grooves. The fitting hole of the second driving block is provided with second fitting grooves on both sides in the second direction. The second transmission gear and the fourth transmission gear are respectively installed in the two second fitting grooves. The first direction and the second direction form an angle and are both perpendicular to the axial direction of the control rod.

[0018] In an alternative embodiment, the fitting surface of the transmission rack is provided with a fitting groove and a fitting protrusion. The fitting protrusion of one of the transmission racks is in sliding fit with the fitting groove of the other transmission rack, and the fitting groove and the fitting protrusion extend along the length direction of the transmission rack.

[0019] In an alternative embodiment, the fitting surface of the transmission rack is provided with a mounting groove. The mounting grooves of the two transmission racks together form a mounting hole. A control rod drive mechanism capable of grouping and regulating power further includes a measuring rod. The measuring rod passes through the mounting hole and is used to extend into the fuel assembly.

[0020] In an alternative embodiment, a first connector is provided at one end of the transmission rack close to the fuel assembly. The connecting member includes a clamping disc and a second connector connected to each other. The second connector is located on the side of the clamping disc away from the fuel assembly and is connected to the first connector. A control rod is installed on the side of the clamping disc close to the fuel assembly.

[0021] The clamping disc is provided with a hollow hole that penetrates the upper and lower sides of the clamping disc.

[0022] The plane where the axes of the second connectors on the two clamping discs are located is a preset plane. The clamping discs are symmetrically arranged with respect to the preset plane, and multiple control rods are symmetrically arranged with respect to the preset plane.

[0023] The beneficial effects of a control rod drive mechanism capable of grouping and regulating power provided by an embodiment of the present invention include: by controlling the movement of the control rods on different connecting members with different driving members, it is possible to allow the control rods in different regions of the corresponding fuel assembly to be independently adjusted. According to the actual reaction conditions above and below the fuel assembly, the positions of different groups of control rods relative to the fuel assembly in their own axial directions can be adjusted respectively, enabling more uniform combustion of the fuel, improving the overall efficiency of the reactor, and making full use of the fuel resources, that is, enabling relatively homogeneous reaction of the fuel within the fuel assembly. Description of the Drawings

[0024] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as limiting the scope. For those of ordinary skill in the art, other related drawings can be obtained based on these drawings without creative efforts.

[0025] Figure 1 It is a schematic structural diagram of a control rod drive mechanism capable of grouping and regulating power provided in this embodiment from a first perspective;

[0026] Figure 2 It is a schematic structural diagram of a control rod drive mechanism capable of grouping and regulating power provided in this embodiment from a second perspective and when the first drive block and the second drive block are not shown;

[0027] Figure 3 It is a schematic structural diagram of two transmission racks during assembly provided in this embodiment;

[0028] Figure 4 It is an exploded view of the first drive block and the second drive block provided in this embodiment;

[0029] Figure 5 It is a schematic structural diagram of the first clamping disc and the second clamping disc provided in this embodiment from a third perspective;

[0030] Figure 6 Schematic structural diagram of the first clamping disk and the second clamping disk provided in this embodiment from the fourth perspective.

[0031] Icons: 1 - A control rod drive mechanism capable of grouped power regulation; 100 - Drive assembly; 110 - First drive block; 111 - First assembly groove; 120 - Second drive block; 121 - Second assembly groove; 101 - Matching hole; 130 - First transmission gear; 140 - Second transmission gear; 150 - Third transmission gear; 160 - Fourth transmission gear; 200 - Transmission assembly; 210 - Transmission rack; 211 - Assembly surface; 212 - Fitting surface; 213 - Matching groove; 214 - Matching protrusion; 215 - First connector; 206 - Mounting hole; 220 - Connecting piece; 221 - First clamping disk; 222 - Second clamping disk; 223 - Control rod; 225 - Second connector; 226 - Hollow hole; 300 - Fuel assembly; 400 - Measuring rod; 2 - Preset plane. Detailed implementation manners

[0032] To make the objectives, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are some but not all of the embodiments of the present invention. Usually, the components of the embodiments of the present invention described and illustrated herein can be arranged and designed in various different configurations.

[0033] Therefore, the following detailed description of the embodiments of the present invention provided in the drawings is not intended to limit the scope of the claimed present invention, but merely represents selected embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts fall within the scope of protection of the present invention.

[0034] It should be noted that: Similar reference numerals and letters denote similar items in the following drawings. Therefore, once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings.

[0035] In the description of the present invention, it should be noted that if terms such as "upper", "lower", "inner", "outer", etc. are used to indicate the orientation or positional relationship, it is based on the orientation or positional relationship shown in the drawings or the orientation or positional relationship in which the product of the present invention is usually placed during use. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be construed as a limitation to the present invention.

[0036] In addition, terms such as "first" and "second" are only used for distinguishing descriptions and should not be construed as indicating or implying relative importance.

[0037] It should be noted that, without conflict, the features in the embodiments of the present invention can be combined with each other.

[0038] The following will introduce in detail the specific structure of a control rod drive mechanism capable of grouped power regulation provided by the embodiments of the present invention and the corresponding technical effects brought thereby with reference to the patent drawings.

[0039] Please refer to Figures 1 - 4 , a control rod drive mechanism 1 capable of grouped power regulation provided by the embodiments of the present invention includes a driving assembly 100, a transmission assembly 200, and a fuel assembly 300. The driving assembly 100 includes a plurality of driving members. The transmission assembly 200 includes a plurality of connecting members 220. A control rod 223 is installed on the connecting member 220. The fuel assembly 300 is located at one end of the control rod 223 away from the connecting member 220. The driving member is used to drive the connecting member 220 to move along the axial direction of the control rod 223 so that the control rod 223 is inserted into or withdrawn from the fuel assembly 300.

[0040] It should be noted that in order to uniformly control the control rod 223 and reduce the number of driving members, some existing control rod drive mechanisms 1 capable of grouped power regulation have the driving members in the control rod drive mechanism 1 simultaneously driving all the control rods 223 to move along the axial direction of the control rod 223 together and insert into the fuel assembly 300 to control the reactor power. It can be understood that since the driving members in the existing control rod drive mechanisms 1 capable of grouped power regulation simultaneously drive all the control rods 223 to move up and down together and insert into the fuel assembly 300 to control the reactor power, when controlling the power, when the control rod 223 is to be inserted into the fuel assembly 300 from top to bottom, the fuel power above the fuel assembly 300 is inhibited, while the fuel below is not affected. Under long-term operation conditions, it will cause non-uniform reactions of the upper and lower fuels, affecting the life of the fuel assembly 300.

[0041] In a nuclear reactor, the neutron flux refers to the number of neutrons passing through a unit area per unit time. The neutron flux distribution directly affects the fission reaction rate inside the fuel assembly 300. The higher the fission reaction rate, the faster the fuel consumption, and the local temperature and pressure will also increase accordingly. Therefore, controlling the neutron flux distribution is crucial for maintaining a uniform reaction inside the fuel assembly 300.

[0042] It has been found that since the drive member controls the up and down movement of all the control rods 223, all the control rods 223 used are lifted or lowered by the same distance at the same time. With such control, the neutron flux distribution above and below the fuel assembly 300 is uneven, resulting in the suppression of the fuel power above, while the fuel below is not easily affected, which will lead to a temperature difference between the upper and lower parts of the fuel assembly 300, thus causing local overheating.

[0043] Moreover, when all the control rods 223 are inserted into the fuel assembly 300 up and down as a whole, the neutron flux distribution inside the fuel assembly 300 cannot be precisely controlled, resulting in uneven fuel combustion and different consumption rates of the fuel above and below, which affects the service life of the fuel.

[0044] The fission reaction rates above and below the fuel assembly 300 are different. By controlling the up and down movement of all the control rods 223 as a whole, the fuel resources cannot be fully utilized, and the reactor efficiency will also be reduced.

[0045] In this embodiment, since there are multiple drive members and the transmission assembly 200 has multiple connecting members 220, and the control rods 223 are installed on the connecting members 220, and each connecting member 220 is connected to a drive member. Therefore, different control rods 223 can be controlled by different drive members to move up and down. It can be seen that when the operator controls the fuel power of the reactor, the control rods 223 on each connecting member 220 can be divided into a group of control rods 223, and under the drive of different drive members, different groups of control rods 223 can be driven to move up and down to achieve independent control of different groups of control rods 223.

[0046] It can be understood that through the grouped drive of the control rods 223, the control rods 223 corresponding to different regions of the fuel assembly 300 can be independently adjusted. According to the actual reaction conditions above and below the fuel assembly 300, the positions of different groups of control rods 223 relative to the fuel assembly 300 in their own axial directions can be adjusted respectively, so as to more precisely adjust the neutron flux distribution inside the fuel assembly 300, make the fission reaction rates above and below the fuel assembly 300 more uniform, and then reduce the temperature difference between the upper and lower parts of the fuel assembly 300, prevent local overheating, thus prolonging the service life of the fuel in the fuel assembly 300, and also enabling the fuel to burn more evenly, improving the overall efficiency of the reactor, making full use of the fuel resources, that is, being able to achieve relatively homogeneous reaction of the fuel in the fuel assembly 300.

[0047] In detail, in this embodiment, the driving member includes a transmission gear and a driving structure (not shown in the figure), the driving structure is used to drive the transmission gear to rotate, the transmission assembly 200 also includes a plurality of transmission racks 210, the transmission rack 210 includes an assembly surface 211, and the assembly surface 211 is provided with a plurality of meshing teeth extending along the axial direction of the control rod 223, and the meshing teeth are meshed with the transmission gear. Each driving member is connected to a transmission rack 210 through a transmission gear, and one end of the transmission rack 210 is connected to the connecting member 220. The number of transmission racks 210, driving members and connecting members 220 is the same.

[0048] It should be noted that, in this embodiment, the length direction of the transmission rack 210 is parallel to the axial direction of the control rod 223, and the transmission gear can only rotate around its own axis and cannot move in other directions.

[0049] That is to say, in this embodiment, the driving member can drive the transmission gear to rotate and then drive the transmission rack 210 to move along the axis direction of the control rod 223. It can be understood that the driving accuracy of the control rod 223 can be improved through the transmission mode of the rack and the gear.

[0050] Of course, in some other embodiments, the driving member may also include other structures. For example, the driving member may also be a linear driving electric cylinder, a pneumatic cylinder or an oil cylinder. The driving end of the driving electric cylinder, the driving end of the driving cylinder or the driving end of the driving oil cylinder is connected to the connecting member 220. Of course, the driving member may also include a linear guide rail and a screw motor. The screw nut of the screw motor is fixedly connected to the connecting member 220.

[0051] In this embodiment, there are two transmission racks 210 and the two transmission racks 210 are movably connected. The transmission rack 210 is in the shape of a triangular prism. The outer peripheral surface of the transmission rack 210 includes two adjacent assembly surfaces 211 and a fitting surface 212 located between the two assembly surfaces 211. The fitting surfaces 212 of the two transmission racks 210 are relative and can move relative to each other in the axial direction of the control rod.

[0052] It can be understood that since the transmission rack 210 has two assembly surfaces 211, it is convenient for the user to install the transmission gear that meshes with itself. When a driving member connected to a transmission rack 210 has two transmission gears, the two transmission gears can be respectively connected to the meshing teeth of the two assembly surfaces 211, thereby effectively improving the transmission efficiency and transmission stability.

[0053] For example, the two driving members are respectively a first driving member and a second driving member. The first driving member includes a first transmission gear 130 and a second transmission gear 140. The second driving member includes a third transmission gear 150 and a fourth transmission gear 160. The first transmission gear 130 and the second transmission gear 140 are respectively engaged with the engaging teeth on two assembly surfaces 211 of one of the transmission racks 210. The third transmission gear 150 and the fourth transmission gear 160 are respectively engaged with the engaging teeth on two assembly surfaces 211 of the other transmission rack 210.

[0054] It can be understood that in the present application, the first transmission gear 130 and the second transmission gear 140 of the first driving member are respectively engaged with the engaging teeth on two assembly surfaces 211 of a transmission rack 210, and the third transmission gear 150 and the fourth transmission gear 160 of the second driving member are respectively engaged with the engaging teeth on two assembly surfaces 211 of another transmission rack 210. Each driving member can drive a transmission rack 210 to move along the axial direction of the control rod 223 through two transmission gears, thereby driving the control rod 223 to move up and down, ensuring the stability of driving the transmission rack 210.

[0055] Certainly, in some embodiments, the number of transmission gears in each driving member can be one, and the transmission gear can be in transmission connection with the engaging teeth on one of the assembly surfaces 211 of each transmission rack 210.

[0056] Specifically, in this embodiment, the four assembly surfaces 211 of the two transmission racks 210 are sequentially connected at an angle, that is to say, the fitting surfaces 212 of the two transmission racks 210 are in contact with each other. Any two adjacent assembly surfaces 211 are arranged at a 90-degree angle.

[0057] Certainly, in some other embodiments, any two assembly surfaces 211 can also be arranged at other angles, such as an obtuse angle or an acute angle.

[0058] Optionally, the first driving member can include two independent driving structures, and the two independent driving structures respectively drive the first transmission gear 130 and the second transmission gear 140 to rotate. Similarly, the second driving member can also include two independent driving structures, and the two independent driving structures are used to respectively and independently drive the third transmission gear 150 and the fourth transmission gear 160 to rotate.

[0059] Specifically, the driving assembly 100 further includes a driving block. The driving block is provided with a fitting hole 101. The inner wall of the fitting hole 101 is provided with an assembly groove for installing the transmission gear. The two transmission racks 210 are inserted into the fitting hole 101. Each transmission gear can rotate relative to the driving block around its own axis, and the transmission gears are all exposed outside the fitting hole 101 for easy connection with the transmission gears.

[0060] Specifically, the mating hole 101 in this embodiment is generally a rectangular hole. Two transmission racks 210 pass through the mating hole 101, and one end of each transmission rack 210 is connected to a connecting member 220.

[0061] Specifically, the number of driving blocks is two, and the two driving blocks are arranged in sequence along the axial direction of the control rod 223. The two driving blocks are a first driving block 110 and a second driving block 120 respectively. First assembly grooves 111 are formed on both sides of the mating hole 101 of the first driving block 110 in a first direction. The first transmission gear 130 and the third transmission gear 150 are respectively installed in the two first assembly grooves 111. Second assembly grooves 121 are formed on both sides of the mating hole 101 of the second driving block 120 in a second direction. The second transmission gear 140 and the fourth transmission gear 160 are respectively installed in the second assembly grooves 121. The first direction and the second direction form an angle and are both perpendicular to the axial direction of the control rod 223.

[0062] It should be noted that both the above-mentioned first driving block 110 and second driving block 120 can be fixed to an external support structure to ensure that the transmission gears in the first driving block 110 and the second driving block 120 can rotate stably.

[0063] It can be understood that in this embodiment, the driving structure is also installed in the driving block to facilitate the driving structure to drive the transmission gear to rotate.

[0064] Specifically, in this embodiment, the first direction, the second direction and the axial direction of the control rod 223 are perpendicular to each other in pairs.

[0065] It can be understood that the first transmission gear 130 and the second transmission gear 140 of the first driving member are arranged in a staggered manner in the axial direction of the control rod 223, that is, the axes of the first transmission gear 130 and the second transmission gear 140 are not on the same horizontal plane. Installing them in a staggered manner in sequence can prevent interference between the first transmission gear 130 and the second transmission gear 140. Similarly, the third transmission gear 150 and the fourth transmission gear 160 of the second driving member are arranged in a staggered manner in the axial direction of the control rod 223, which can also prevent interference between the third transmission gear 150 and the fourth transmission gear 160.

[0066] A mating groove 213 and a mating protrusion 214 are provided on the mating surface 212 of the transmission rack 210. The mating protrusion 214 of one transmission rack 210 is in sliding fit with the mating groove 213 of the other transmission rack 210. The mating groove 213 and the mating protrusion 214 extend along the length direction of the transmission rack 210. Specifically, in this embodiment, the mating protrusions 214 and the mating grooves 213 in the two transmission racks 210 are in one-to-one sliding fit.

[0067] One end of the transmission rack 210 close to the fuel assembly 300 is provided with a first connector 215. The connecting member 220 includes a clamping disc and a second connector 225 connected to each other. The second connector 225 is located on the side of the clamping disc away from the fuel assembly 300 and is connected to the first connector 215. A control rod 223 is installed on the side of the clamping disc close to the fuel assembly 300.

[0068] It should be noted that the connection mode between the first connector 215 and the second connector 225 can be a detachable connection or a non-detachable connection. For example, the first connector 215 can be provided with an internal threaded hole, and the outer peripheral wall of the second connector 225 can be provided with an external thread threadedly connected to the first connector 215. Or the outer peripheral wall of the first connector 215 can be provided with an external thread, and the second connector 225 can be provided with an internal threaded hole threadedly connected to the first connector 215. Or, the first connector 215 and the second connector 225 can also be connected by welding or expansion connection. It should be noted that in order to facilitate the axis direction of the control rod 223 to be parallel to the height direction so that the control rod 223 can move along its own axis, when the clamping disc is connected to the transmission rack 210, it is necessary to ensure that the outer side surface of the clamping disc is parallel to the side surface of the transmission rack 210.

[0069] Specifically, in this embodiment, each clamping disc is installed with a plurality of control rods 223. Since the number of the connecting members 220 and the number of the transmission racks 210 in this embodiment are both two, the number of the control rods 223 on the clamping discs of the two connecting members 220 is the same, and the arrangement of the plurality of control rods 223 on the two clamping discs is substantially symmetric. The symmetry can be central symmetry or axial symmetry.

[0070] Specifically, each clamping disc in this embodiment is provided with 12 control rods 223.

[0071] Of course, in some alternative embodiments, the plurality of control rods 223 on the two clamping discs can also be arranged in other ways.

[0072] That is to say, the control rods 223 in this embodiment are divided into two groups. The two transmission racks 210 are respectively driven by the first driving member and the second driving member, and then the control rods 223 on the two connecting members 220 are respectively driven to move along the axis direction of the control rods 223.

[0073] It can be understood that through the arrangement of the mating groove 213 and the mating protrusion 214, it is convenient for the two transmission racks 210 to slide relative to each other in the axis direction of the control rods 223, and it is also convenient for the positioning and assembly of the two transmission racks 210. After the mating protrusion 214 of one transmission rack 210 is in sliding fit with the mating groove 213 of the other transmission rack 210, the mating surfaces 212 of the two transmission racks 210 are in contact with each other.

[0074] Specifically, the outer peripheral wall of the mating protrusion 214 in this embodiment is an arc wall. Similarly, the inner peripheral wall of the mating groove 213 is an arc inner wall adapted to the mating protrusion 214, so as to reduce the friction when the two transmission racks 210 move relative to each other.

[0075] It can be understood that in order to facilitate the operator to detect the internal situation of the fuel assembly 300, a control rod drive mechanism 1 with group-by-group power regulation further includes a measuring rod 400. An installation groove is provided on the fitting surface 212 of the transmission rack 210. The installation grooves of the two transmission racks 210 together form an installation hole 206. The measuring rod 400 passes through the installation hole 206 and is used to extend into the fuel assembly 300. It should be noted that a part of the measuring rod 400 is inserted into the fuel assembly 300 and is not fixed on the transmission rack 210. Therefore, the measuring rod 400 and the installation hole 206 are in clearance fit. When the transmission rack 210 moves along the axis direction of the control rod 223, it will move relative to the measuring rod 400.

[0076] It should be noted that the length dimension of the control rod 223 in this embodiment can be greater than or equal to the length dimension inside the fuel assembly 300.

[0077] Specifically, a control rod drive mechanism 1 with group-by-group power regulation provided in this embodiment can effectively make the fuel reactions of various parts of the fuel assembly 300 uniform by alternately inserting and pulling out the control rods 223 on the two clamping disks into and out of the fuel assembly 300.

[0078] Please refer to Figures 5 - 6 , the clamping disk is provided with a hollow hole 226, and the hollow hole 226 penetrates through the upper and lower sides of the clamping disk. The lower side of the clamping disk can be understood as the side of the clamping disk close to the fuel assembly 300, and the upper side of the clamping disk can be understood as the side of the clamping disk close to the first connector 215.

[0079] It can be understood that the clamping disk can reduce its own weight through the hollow hole 226 to reduce the load of the drive assembly 100. It should be noted that since the control rod drive mechanism 1 with group-by-group power regulation provided in this embodiment inserts and pulls out the control rod 223 up and down into the fuel assembly 300, the heat exchange liquid will flow from bottom to top. When the heat exchange liquid passes through the clamping disk, since the clamping disk is provided with the hollow hole 226, the heat exchange liquid will flow up and down through the hollow hole 226, improving the flow efficiency of the heat exchange liquid and reducing the obstruction of the clamping disk to the heat exchange liquid.

[0080] And through grouping, it is possible to reasonably control the insertion or extraction of the two groups of control rods 223 into or out of the fuel assembly 300 to regulate the uniform reaction of the fuel assembly 300. For example, the two clamping disks are respectively named the first clamping disk 221 and the second clamping disk 222.

[0081] It can be understood that in this embodiment, both the first clamping disc 221 and the second clamping disc 222 are provided with a plurality of hollow holes 226. It should be noted that the arrangement of the hollow holes 226 on the first clamping disc 221 may be different from or the same as that of the hollow holes 226 on the second clamping disc 222, and no specific limitation is made here.

[0082] Specifically, in this embodiment, the plane where the axes of the second connectors 225 on the two clamping discs are located is the preset plane 2, the clamping discs are symmetrically arranged with respect to the preset plane 2, and the plurality of control rods 223 are symmetrically arranged with respect to the preset plane 2.

[0083] In this embodiment, the outer contour surfaces of the second connectors 225 of the first clamping disc 221 and the second clamping disc 222 are cylindrical surfaces. The axis of the second connector 225 is parallel to the axis of the control rod 223.

[0084] That is to say, the axes of the second connectors 225 of the first clamping disc 221 and the second clamping disc 222 in this embodiment are both located on the preset plane 2, and the first clamping disc 221 in this embodiment is symmetric with respect to the preset plane, and the second clamping disc 222 is also symmetrically arranged with respect to the preset plane 2. Specifically, all the control rods 223 on the first clamping disc 221 and the second clamping disc 222 are symmetric with respect to the preset plane 2. It can be understood that since the first clamping disc 221 and the second clamping disc 222 are symmetric with respect to the preset plane 2, and the plurality of control rods 223 are also symmetrically arranged with respect to the preset plane 2, it can ensure that the arrangement of the control rods 223, the first clamping disc 221 and the second clamping disc 222 is more regular, which is convenient for maintenance and repair, and the plurality of control rods 223 symmetrically arranged with respect to the preset plane 2 can reduce the power fluctuation caused by the local neutron flux change and reduce the uneven distribution of the intermediate flux inside the reactor, improve the stability of the reactor combustion, and can enhance the controllability of the device, better control the power output of the reactor, and also make the fuel burn more evenly in the fuel assembly 300.

[0085] When the two groups of control rods 223 perform 1 / 2 full power operation, the two driving members can alternately insert the control rods 223 on the first clamping disc 221 and the second clamping disc 222 completely into the fuel assembly 300. That is to say, the control rods 223 on the first clamping disc 221 are first completely inserted into the fuel assembly 300, the control rods 223 on the second clamping disc 222 are not inserted into the fuel assembly 300, and then the control rods 223 on the first clamping disc 221 are completely pulled out of the fuel assembly 300, and then the control rods 223 on the second clamping disc 222 are completely inserted into the fuel assembly 300, so as to react alternately.

[0086] When the two groups of control rods 223 are operating at 1 / 4 full power, the control rods 223 on the first clamping disc 221 and the second clamping disc 222 can be alternately inserted into the fuel assembly 300 by half of their lengths. That is to say, the control rods 223 on the first clamping disc 221 can be inserted into the fuel assembly 300 by half of their lengths in advance, and the control rods 223 on the second clamping disc 222 are not inserted into the fuel assembly 300. Then, the control rods 223 on the first clamping disc 221 are completely withdrawn from the fuel assembly 300, and then the control rods 223 on the second clamping disc 222 are inserted into the fuel assembly 300 by half of their lengths, so as to alternate the reaction.

[0087] When the two groups of control rods 223 are operating at 3 / 4 full power, the control rods 223 on one of the clamping discs in the first clamping disc 221 can be completely inserted into the fuel assembly 300, and the control rods 223 on the second clamping disc 222 are inserted into the fuel assembly 300 by half of their lengths. After a period of time, the control rods 223 with half of their lengths inserted on the second clamping disc 222 are continuously inserted until the control rods 223 on the second clamping disc 222 are completely inserted into the fuel assembly 300, and the control rods 223 on the first clamping disc 221 are withdrawn by half of their lengths outside the fuel assembly 300, so that only half of the length of the control plate on the first clamping disc 221 is inserted into the fuel assembly 300, thus alternating the reaction.

[0088] In summary, a control rod drive mechanism 1 provided by an embodiment of the present invention for grouping and regulating power includes a drive assembly 100, a transmission assembly 200, and a fuel assembly 300. The drive assembly 100 includes a plurality of driving members, the transmission assembly 200 includes a plurality of connecting members 220, the control rods 223 are installed on the connecting members 220, and the fuel assembly 300 is located at one end of the control rods 223 away from the connecting members 220. Among them, the driving members are used to drive the connecting members 220 to move along the axial direction of the control rods 223, so that the control rods 223 are inserted into or withdrawn from the fuel assembly 300. Through the grouped drive of the control rods 223, independent adjustment of the control rods 223 corresponding to different regions of the fuel assembly 300 is allowed. According to the actual reaction conditions above and below the fuel assembly 300, the positions of different groups of control rods 223 relative to the fuel assembly 300 in their own axial directions can be adjusted respectively, the fuel can be burned more uniformly, the overall efficiency of the reactor can be improved, and the fuel resources can be fully utilized, that is, relatively homogeneous reaction of the fuel in the fuel assembly 300 can be achieved.

[0089] The above is only the specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed by the present invention should be covered by the protection scope of the present invention.

Claims

1. A control rod drive mechanism capable of grouping and regulating power, characterized in that Comprising: A driving assembly (100), the driving assembly (100) comprising a plurality of driving members; A transmission assembly (200), the transmission assembly (200) comprising a plurality of connecting members (220), a control rod (223) being mounted on each connecting member (220), and each connecting member (220) being connected to one of the driving members; A fuel assembly (300), the fuel assembly (300) being located at an end of the control rod (223) away from the connecting member (220); Wherein, the driving member is configured to drive the connecting member (220) to move along the axial direction of the control rod (223), so that the control rod (223) is inserted into or withdrawn from the fuel assembly (300); The driving member includes a transmission gear and a driving structure, and the driving structure is configured to drive the transmission gear to rotate; The transmission assembly (200) further includes a plurality of transmission racks (210), the transmission racks (210) including an assembly surface (211), a plurality of engaging teeth extending along the axial direction of the control rod (223) being provided on the assembly surface (211), and the engaging teeth meshing with the transmission gear. Each driving member is in transmission connection with one of the transmission racks (210) through the transmission gear. One end of the transmission rack (210) is connected to the connecting member (220), and the number of the transmission racks (210), the driving members and the connecting members (220) is the same; The number of the transmission racks (210) is two and the two transmission racks (210) are movably connected. The transmission racks (210) are triangular prism-shaped, and the outer peripheral surface of the transmission rack (210) includes two adjacent assembly surfaces (211) and a fitting surface (212) located between the two assembly surfaces (211). The fitting surfaces (212) of the two transmission racks (210) face each other and can move relative to each other in the axial direction of the control rod (223).

2. The control rod drive mechanism capable of grouping and regulating power according to claim 1, wherein: The four assembly surfaces (211) on the two transmission racks (210) are sequentially connected at an angle, and any two adjacent assembly surfaces (211) are arranged at an angle of 90 degrees.

3. The control rod drive mechanism capable of grouping and regulating power according to claim 1, wherein: The two driving members are respectively a first driving member and a second driving member. The first driving member includes a first transmission gear (130) and a second transmission gear (140), and the second driving member includes a third transmission gear (150) and a fourth transmission gear (160). The first transmission gear (130) and the second transmission gear (140) respectively mesh with the engaging teeth on the two assembly surfaces (211) of one of the transmission racks (210), and the third transmission gear (150) and the fourth transmission gear (160) respectively mesh with the engaging teeth on the two assembly surfaces (211) of the other transmission rack (210).

4. The control rod drive mechanism capable of grouping and regulating power according to claim 3, wherein: The driving assembly (100) further includes a driving block, the driving block is provided with a fitting hole (101), an assembly groove for installing the transmission gear is arranged on the inner wall of the fitting hole (101), the two transmission racks (210) are arranged through the fitting hole (101), each transmission gear can rotate relative to the driving block around its own axis, and the transmission gears are all exposed out of the fitting hole (101).

5. The control rod drive mechanism capable of grouping and regulating power according to claim 4, characterized in that: The number of the driving blocks is two, and the two driving blocks are arranged in sequence along the axial direction of the control rod (223). The two driving blocks are respectively a first driving block (110) and a second driving block (120). First assembly grooves (111) are arranged on both sides of the fitting hole (101) of the first driving block (110) along the first direction. The first transmission gear (130) and the third transmission gear (150) are respectively installed in the two first assembly grooves (111). Second assembly grooves (121) are arranged on both sides of the fitting hole (101) of the second driving block (120) along the second direction. The second transmission gear (140) and the fourth transmission gear (160) are respectively installed in the two second assembly grooves (121). The first direction and the second direction form an angle and are both perpendicular to the axial direction of the control rod (223).

6. The control rod drive mechanism capable of grouping and regulating power according to claim 1, characterized in that: A fitting groove (213) and a fitting protrusion (214) are arranged on the fitting surface (212) of the transmission rack (210). The fitting protrusion (214) of one of the transmission racks (210) is in sliding fit with the fitting groove (213) of the other transmission rack (210). The fitting groove (213) and the fitting protrusion (214) extend along the length direction of the transmission rack (210).

7. The control rod drive mechanism capable of grouping and regulating power according to claim 6, characterized in that: An installation groove is arranged on the fitting surface (212) of the transmission rack (210). The installation grooves of the two transmission racks (210) jointly form an installation hole (206). The control rod drive mechanism capable of grouping and regulating power further includes a measuring rod (400). The measuring rod (400) passes through the installation hole (206) and is used for extending into the fuel assembly (300).

8. The control rod drive mechanism capable of grouping and regulating power according to claim 1, characterized in that: A first connector (215) is arranged at one end of the transmission rack (210) close to the fuel assembly (300). The connecting piece (220) includes a clamping disc and a second connector (225) connected to each other. The second connector (225) is located on the side of the clamping disc away from the fuel assembly (300) and is connected to the first connector (215). A control rod (223) is installed on the side of the clamping disc close to the fuel assembly (300); The clamping disc is provided with a hollow hole (226), and the hollow hole (226) penetrates through the upper and lower sides of the clamping disc; The plane where the axes of the second connectors (225) on the two clamping discs are located is a preset plane (2), the clamping discs are symmetrically arranged with respect to the preset plane (2), and the plurality of control rods (223) are symmetrically arranged with respect to the preset plane (2).

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