A method and device for designing a traveling wave magnetic field type linear motor of a control rod drive mechanism
By designing a traveling wave magnetic field linear motor for the control rod drive mechanism and optimizing its structure to improve thrust and reduce wear, the problems of large size and low efficiency of existing drive mechanisms have been solved, achieving miniaturization and high-efficiency operation.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- NUCLEAR POWER INSTITUTE OF CHINA
- Filing Date
- 2026-03-16
- Publication Date
- 2026-07-14
Smart Images
Figure FT_1 
Figure FT_2 
Figure FT_3
Abstract
Description
Technical Field
[0001] This invention belongs to the technical field of nuclear reactor control rod drive mechanism, specifically relating to a design method and device for a traveling wave magnetic field linear motor for a control rod drive mechanism. Background Technology
[0002] Control rod drive mechanisms are key equipment in nuclear reactors, enabling functions such as reactor startup, power regulation, normal shutdown, and emergency shutdown. They serve as the actuators for the reactor control and protection system. Various control rod drive mechanisms have unique structures and characteristics, and are applicable to different types of reactors. Currently, widely used control rod drive mechanisms mainly include mechanical drive mechanisms, stepper drive mechanisms (including magnetic lifting drive mechanisms and stepper motor-chain drive mechanisms), hydrostatic drive mechanisms, and hydraulic drive mechanisms. Among these, magnetic lifting drive mechanisms have advantages such as simple structure, high lifting force, low wear, and long service life. Compared with other drive methods, even if a critical component fails, the reactor can be shut down quickly. Therefore, magnetic lifting drive mechanisms are commonly used in nuclear power plants.
[0003] Currently, most reactors use drive mechanisms that are large in size and lack flexibility in controlling the position of the control rods. To reduce the size of the drive mechanism and adapt it to the requirements of reactor miniaturization, it is necessary to optimize the existing drive mechanism.
[0004] Linear motors offer advantages such as simple structure, fast response, high temperature resistance, and high reliability. Furthermore, they can be modularly designed, manufactured, and easily maintained, which can reduce the overall cost of the mechanism to some extent. However, existing linear motors suffer from drawbacks such as low power factor, low thrust density, low efficiency, and lack of modularity, making it difficult to meet the reactor's demand for high lifting force in the drive mechanism. Summary of the Invention
[0005] The technical problem solved by this invention is to provide a design method and device for a traveling wave magnetic field linear motor for a control rod drive mechanism, which can solve the technical problem that existing drive mechanisms are too large to be suitable for miniaturized reactors.
[0006] The technical solution adopted in this invention is as follows: A design method for a traveling wave magnetic field linear motor with a control rod drive mechanism includes the following steps: S1. Determine the technical specifications, including lifting force and movement speed; S2. Based on the technical specifications determined in S1, determine the initial values of the main dimensions, the tooth groove dimensions, and the stator core yoke height. The initial values of the main dimensions include the total length of the motor, the inner diameter of the stator, the number of pole pairs, and the pole pitch. S3. Calculate the inner and outer diameters of the mover. Based on the tooth groove dimensions and stator core yoke height determined in S3, and the limitation imposed by the drive mechanism on the inner diameter of the mover hole, calculate the inner and outer diameters of the mover. S4. Given the initial value of the stator current density; S5. Determine the stator winding parameters, which include the number of turns, slot fill factor, and conductor diameter. S6. Determine whether the winding temperature rise meets the design requirements; S7. Determine whether the lifting force meets the design requirements; S8, optimization of the traveling wave magnetic field linear motor for the control rod drive mechanism.
[0007] In step S6, the winding temperature rise is calculated and compared with the design requirements. If the design requirements are met, the next step is performed; if the design requirements are not met, the stator current density is changed, and steps S4-S6 are repeated until the winding temperature rise meets the design requirements.
[0008] In step S7, the lifting force of the linear motor device is calculated based on its parameters and compared with the technical specifications. If the design requirements are met, the design parameters are output and the entire design process ends. If the design requirements are not met, the main dimensions given in step S2 are changed, and steps S3-S6 are repeated until the design requirements are met and the design process ends.
[0009] S8 specifically includes the following steps: S801. Select optimization variables based on the design dimensions of the linear motor; S802. Set the variable domain to determine the range of values for the optimization variables; S803. Define the objective function; S804, Finite Element Simulation; S805, Calculate fitness; S806, the optimal solution is obtained.
[0010] In step S801, the selection of optimization variables needs to meet two conditions: Condition 1: The optimization variables should be selected from the design parameters that have a significant impact on the objective function; Condition 2: These design parameters are relatively independent.
[0011] In step S803, the average thrust of the motor, the thrust fluctuation rate, and the weight of the motor mover are selected and a weighted objective function is constructed. The objective function is defined as follows: ; where r i (i=1~4) represents the rate of change, defined as follows: Where x represents the selected optimization variable, Fz0 Fluctuation0 and Weight0 correspond to the axial electromagnetic thrust, thrust fluctuation rate, and weight of the linear motor before optimization under constant current control conditions, respectively; F z1 Fluctuation1 and Weight1 represent the optimized axial electromagnetic thrust, thrust fluctuation rate, and motor weight of the linear motor; k is selected. i (i=1~3) are the weight coefficients of the optimization objective. Different weight coefficients are selected for optimization according to different needs.
[0012] In step S805, the optimization results of the average thrust of the motor and the weight of the motor mover are superimposed according to the objective function to obtain the optimization process of the effective thrust of the motor.
[0013] In step S806, after obtaining the optimization result, the design parameters of the optimization scheme are rounded to ensure that the design scheme meets the processing requirements.
[0014] A control rod drive mechanism traveling wave magnetic field linear motor device includes a stator assembly and a mover, the stator assembly and the mover being slidably connected in the vertical direction; the stator assembly includes a stator yoke, a sealing shell, a first lamination, an outer shell, a second lamination, an elastic retaining ring, and coils; the stator yoke is fixedly installed inside the outer shell, the stator yoke being a hollow cylindrical shape, with an annular mounting groove on the upper and lower inner walls of the stator yoke, the mounting grooves being fixedly connected to the elastic retaining rings; a first lamination is fixedly installed at the lower part of the upper elastic retaining ring and the upper part of the lower elastic retaining ring respectively; multiple coils are evenly distributed between the two first laminations along the axis of the stator yoke, the multiple coils forming a coil group; two adjacent coils are separated by a second lamination; the sealing shell is coaxially arranged with the coils, first lamination, second lamination, and stator yoke; both first lamination and second lamination have through holes in the vertical direction.
[0015] The mover includes an inner shielding shell, a guide rod, and an outer shielding shell. The guide rod is a hollow rod with a hollow cylindrical inner shielding shell fixed inside and a hollow cylindrical outer shielding shell fixed outside. Multiple slots are formed on the outer side of the guide rod along the vertical direction, and magnetic rings are placed in the slots. The guide rod is made of silicon steel, iron-based amorphous alloy, or iron-aluminum alloy pure iron. The inner and outer shielding shells are made of austenitic stainless steel or martensitic stainless steel. The magnetic rings are made of DT4E.
[0016] The beneficial effects of this invention are: (1) The present invention provides a design method for a traveling wave magnetic field linear motor for a control rod drive mechanism, which can obtain initial design parameters that meet the design requirements, select appropriate optimization variables and define objective functions, use the finite element method to optimize the optimization variables of the linear motor, and finally solve the most reasonable linear motor structure, effectively improve the average thrust of the linear motor, reduce thrust fluctuation and reduce the mass of the mover, so as to meet the design requirements of miniaturized reactors.
[0017] (2) The traveling wave magnetic field linear motor device for control rod drive mechanism provided by the present invention has the advantages of simple structure and small size, effectively avoiding the technical problem of wear of drive rod during operation of existing drive mechanism. Using this device can extend the service life of drive mechanism and improve the economic benefits of reactor.
[0018] (3) The present invention provides a control rod drive mechanism traveling wave magnetic field linear motor device, which reduces the heat generation of the linear motor and improves the load capacity of the linear motor by setting the mover as a composite structure of corrosion-resistant material, high magnetic permeability material and corrosion-resistant material, so that the mover meets the conditions of high temperature, high corrosion and high radiation. Attached Figure Description
[0019] To more clearly illustrate the embodiments of the present invention, the accompanying drawings used in describing the embodiments of the present invention will be briefly described below. Obviously, the drawings described below are merely some embodiments recorded in the present invention. Those skilled in the art can derive other drawings from the following drawings without any creative effort.
[0020] Figure 1 This is a flowchart of a design method for a traveling wave magnetic field linear motor device for a control rod drive mechanism provided by the present invention; Figure 2 This is a flowchart illustrating the given technical specifications in this invention; Figure 3 This is a schematic diagram of the grid division for a linear motor; Figure 4 This is the result of optimizing the average thrust of the linear motor; Figure 5 This is the result of thrust fluctuation optimization for linear motors; Figure 6 It is the result of optimizing the thrust fluctuation of the motor; Figure 7 It is the result of optimizing the mass of the motor's mover; Figure 8 This is a schematic diagram showing how the average thrust varies with the magnitude of the driving current; Figure 9 This is a schematic diagram showing how the average thrust varies with the driving frequency; Figure 10 This is a schematic diagram showing how the average thrust changes with the magnitude of the velocity. Figure 11 This is a schematic diagram of the traveling wave magnetic field linear motor device for the control rod drive mechanism of this application; Figure 12 This is an exploded schematic diagram of the stator of the traveling wave magnetic field linear motor device for the control rod drive mechanism of this application; Figure 13 This is a schematic diagram of the stator yoke; Figure 14 This is a schematic diagram of the mover structure; Figure 15 This is a schematic diagram of the guide rod; Figure 16 This is a schematic diagram of a magnetic ring; In the diagram: 1-Stator yoke, 2-Sealing shell, 3-Laminator 1, 4-Outer shell, 5-Laminator 2, 6-Elastic retaining ring, 7-Coil, 9-Motor, 11-Slot 1, 12-Mounting slot, 13-Inner shielding shell, 14-Guide rod, 15-Outer shielding shell, 16-Magnetic ring, 141-Slot 2. Detailed Implementation
[0021] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of the present invention.
[0022] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., refer to the orientation or positional relationship shown in the accompanying drawings, and are used only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.
[0023] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or a connection through an intermediate medium; and they can refer to the internal communication between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.
[0024] like Figure 1-10 As shown, the present invention provides a design method for a traveling wave magnetic field linear motor for a control rod drive mechanism, comprising the following steps: S1. Determine the technical specifications, including lifting force, speed of movement, etc. In this embodiment, the specific technical specifications are shown in Table 1: Table 1 Technical Specifications Step S1: Given technical specifications: lifting force 600N, maximum speed .
[0025] S2. Based on the technical specifications determined in S1, determine the initial values of the main dimensions, the tooth groove dimensions, and the stator core yoke height. The initial values of the main dimensions include the total length of the motor, the inner diameter of the stator, the number of pole pairs, and the pole pitch. In this embodiment, the total length of the motor is 394mm, the stator inner diameter is 46.6mm, the number of pole pairs is 2, the pole pitch is 96mm, the stator slot width is 10mm, the stator tooth width is 6mm, the stator slot depth is 30mm, and the stator core yoke height is 5.2mm. S3. Calculate the inner and outer diameters of the mover. Based on the tooth groove dimensions and stator core yoke height determined in S3, and the limitation imposed by the drive mechanism on the inner diameter of the mover hole, calculate the inner and outer diameters of the mover. In this embodiment, the inner diameter of the mover is 8mm and the outer diameter of the mover is 44mm; S4. Given the initial value of the stator current density; In this embodiment, based on the design requirements of a large, intermittent load, the current density is set to 15 A / mm². 2 ; S5. Determine the stator winding parameters, including the number of turns, slot fill factor, conductor diameter, etc. In this embodiment, the slot fill factor is 75%, the wire diameter is 1.4mm, and the number of turns per slot winding is = ; S6. Determine if the winding temperature rise meets the design requirements. Calculate the winding temperature rise and compare it with the design requirements. If it meets the design requirements, proceed to the next step. If it does not meet the design requirements, change the stator current density and repeat steps S4-S6 until the winding temperature rise meets the design requirements.
[0026] S7. Determine if the lifting force meets the design requirements. Calculate the lifting force based on the parameters of the linear motor device and compare it with the technical specifications. If it meets the design requirements, output the design parameters, and the entire design process ends. If it does not meet the design requirements, change the main dimensions given in step S2 and repeat steps S3-S6 until the design requirements are met, ending the design process.
[0027] In this embodiment, the initial design parameters of the final linear motor device are shown in Table 2.
[0028] Table 2 Initial design parameters of the linear motor device S8. Optimization of the traveling wave magnetic field linear motor for the control rod drive mechanism, specifically including the following steps: S801. Based on the design dimensions of the linear motor, including stator outer diameter, stator inner diameter, mover outer diameter, mover inner diameter, stator length, air gap width, stator pole pitch, stator slot width, stator tooth width, stator slot depth, number of conductors per slot, yoke thickness, and sealing shell thickness, select optimization variables. Appropriate design parameters are selected as optimization variables, and the performance of the drive mechanism is optimized by optimizing these parameters. The selection of optimization variables directly affects the optimization effect of the drive mechanism, so the selection of optimization variables generally needs to meet two conditions: Condition 1: The optimization variables should be selected from the design parameters that have a significant impact on the objective function.
[0029] Condition 2: These design parameters are relatively independent.
[0030] Only when both conditions are met can other relevant parameters be derived and determined based on the selected optimization variables. In this embodiment, the selected optimization variables are: slot width, slot depth, tooth width, tooth height, yoke height, mover inner diameter, mover outer diameter, and drive frequency.
[0031] From the perspective of the linear motor itself, optimizing it essentially involves increasing its electromagnetic thrust, reducing thrust fluctuations, and decreasing mover weight. The magnitude of the electromagnetic thrust generated by a linear induction motor is determined by the motor's magnetic flux density and structure. Therefore, the optimization of a linear motor is mainly divided into two parts: primary optimization and secondary optimization. The primary of the linear motor is mounted on the reactor control rod drive frame, and its installation space is limited. Therefore, the design scope for primary optimization is very narrow, which presents certain difficulties. The secondary of the linear motor reciprocates within the reactor to control the reactor's reaction rate, and its design scope is also limited. The optimization variables selected here are: slot width, slot depth, tooth width, yoke height, mover inner / outer diameter, and drive frequency. The basic stator structure of the linear induction motor can be determined using four variables: slot width, slot depth, tooth width, and yoke thickness. The mover inner and outer diameters correspond to the mover structure. These seven variables determine the overall structure and control parameters of the linear induction motor, demonstrating the effectiveness of their selection. Table 3 lists the names of the seven optimization variables and their corresponding symbols.
[0032] Table 3 Optimization parameters for linear motors S802. Set the variable domain to optimize the range of variable values, which is often constrained by actual conditions. For example, it is limited by manufacturing processes in terms of technology, and its performance and size are also constrained by design requirements. In particular, due to the limited space inside the reactor, the dimensions of the linear motor must meet the installation requirements.
[0033] The range of values for optimization variables is not infinite; it is constrained by certain practical conditions. Technically, it is limited by manufacturing processes, and in terms of performance and size, it is also constrained by design requirements. Medium- and low-speed linear motors use a primary core made of laminated silicon steel sheets, and the length and radius of the primary core are limited by the finite space of the control rod drive frame. According to the initial design parameters in Table 2, the stator length is initially set at 192mm. The sum of the stator slot width and tooth width is 16mm for the stator tooth pitch. Considering the influence of core saturation and the number of winding turns on the air gap magnetic flux density and motor thrust, the stator tooth width is set to the range of {Wt|2≤Wt≤9}, and the stator slot width Ws = 16-Wt, {Ws|7≤Ws≤14}. Simultaneously, the yoke thickness also affects the number of winding turns and core saturation. Limited by the maximum outer diameter of the motor (120mm), the yoke height is set to the range of {Hy|2≤Hy≤6}. A deeper stator slot accommodates more winding turns but also limits the motor's rotor size. The inner diameter affects the magnetic flux density and weight of the mover. Therefore, the range of values for the stator slot depth is: {Ds|20≤Ds≤35}. The inner diameter of the motor mover is limited to greater than 7.5mm due to design requirements. The outer diameter of the mover is affected by the primary structural parameters of the motor. Since the maximum outer diameter of the motor is 117mm, the outer diameter of the mover is D22 = 117 - yoke height Hy × 2 - slot depth Ds × 2 - air gap width × 2. Considering the influence of the mover thickness on leakage flux and air gap magnetic flux density, the range of values for the inner diameter of the mover is: {D21|7.5≤D21≤12}, and the range of values for the outer diameter of the mover is: {D22|33≤D22≤71}. The range of values for the motor drive frequency is: {f|33≤f≤71}. Based on the above constraints, the range of values for the optimization variables can be obtained. The specific range of values for the optimization variables is shown in Table 4.
[0034] Table 4. Range of values for motor optimization variables S803, Define the objective function.
[0035] For the optimization of the linear induction motor used in the control rod drive mechanism, the average thrust, thrust fluctuation rate, and motor mover weight were selected to construct the objective function using a weighted method. The purpose of this invention is to maximize the motor thrust within the maximum outer diameter range, improve thrust density, reduce thrust fluctuation, and reduce mover weight. To obtain the optimal design parameters, the objective function is defined as follows: Among them, r i (i=1~4) represents the rate of change, defined as follows: Where x represents the selected optimization variable, F z0Fluctuation0 and Weight0 correspond to the axial electromagnetic thrust, thrust fluctuation rate, and weight of the linear motor before optimization under constant current control conditions, respectively. z1 Fluctuation1 and Weight1 represent the optimized axial electromagnetic thrust, thrust fluctuation rate, and motor weight of the linear motor, respectively. k is selected. i (i=1~3) represents the weight coefficients of the optimization objective. Different weight coefficients can be selected for optimization according to different needs.
[0036] In this embodiment, the motor thrust is the primary optimization target, with a value range of approximately 400. The fluctuation range of the motor thrust is between 0 and 1. According to the parameters in Table 4, the weight of the motor mover is approximately 4 kg. To unify the unit of the motor mover weight's influence on the thrust with the unit of the motor thrust, k1 = 1 and k3 = 9.8 are set. Because the magnitude of the motor thrust fluctuation is very small, to ensure its role in the objective function, k2 = 10 is set to avoid it being ignored during the optimization process.
[0037] S804, Finite Element Simulation.
[0038] Finite element analysis software was used to perform finite element simulation of the linear motor. The mesh generation result of the linear motor is shown below. Figure 3 As shown, the optimization results of the average thrust of the linear motor are as follows: Figure 4 As shown, the optimization results for thrust fluctuation of the linear motor are as follows: Figure 5 As shown, the optimized results of the motor's mover mass are as follows: Figure 6 Show.
[0039] With a martensitic sealing shell-martensitic mover structure CLIM and a mover length of 1000mm, the minimum mover mass can be optimized to 10.6kg, corresponding to a mover force of 103.91N.
[0040] S805, Calculate fitness.
[0041] The optimization results of the motor's average thrust and the motor's mover weight are superimposed according to the objective function to obtain the optimization process of the motor's effective thrust, as follows: Figure 7 The maximum effective thrust output is shown to be 323.13 N. Under the premise of meeting the motor's travel range, the thrust of the two-section unit motor is expected to reach 600 N, which meets the design requirements.
[0042] S806, the optimal solution is obtained.
[0043] The design parameters for the linear motor under maximum thrust conditions are shown in Table 5. Considering manufacturing process limitations, the design parameters of the optimized scheme need to be rounded after obtaining the optimization results to ensure that the design scheme meets the manufacturing process requirements. The final optimized design parameters are shown in Table 6.
[0044] Table 5 Optimized Design Parameters Table 6 Final Optimized Design Parameters of Linear Motor Device Based on the initial design parameters of the linear motor device in Table 2 and the final optimized design parameters in Table 6, two types of martensitic sealed shell-martensitic mover structure linear motors with different structural parameters were modeled. The driving frequency, current density, and motion speed of the motor simulation model were parametrically designed, and the driving characteristics and the magnitude of the output thrust of the motor were simulated and compared. The variation of average thrust with the driving current is shown below. Figure 8 As shown, under the same current conditions, the optimized thrust is increased by approximately 10%. The average thrust varies with the magnitude of the drive frequency as follows: Figure 9 As shown, under a current frequency of 60Hz, the optimized average thrust is improved by 9%. The change in average thrust with velocity is shown below. Figure 10 It can be observed that when the speed of motion is greater than 0.1 m / s, the optimized average thrust is improved by about 9%.
[0045] like Figures 11 to 16 As shown, this invention provides a traveling wave magnetic field linear motor device for a control rod drive mechanism, including a stator assembly and a mover 9, which are slidably connected vertically. The stator assembly includes a stator yoke 1, a sealing shell 2, a lamination 3, a housing 4, a lamination 5, an elastic retaining ring 6, and coils 7. The stator yoke 1 is fixedly installed inside the housing 4. The stator yoke 1 is generally hollow cylindrical, with an annular mounting groove 12 on both the upper and lower inner walls. The mounting groove 12 is fixedly connected to the elastic retaining ring 6. A lamination 3 is fixedly installed at the lower part of the upper elastic retaining ring 6 and the upper part of the lower elastic retaining ring 6, respectively. Multiple coils 7 are evenly distributed between the two laminations 3 along the axial direction of the stator yoke 1, forming a coil group. Two adjacent coils 7 are separated by lamination 5. The sealing shell 2 is coaxially arranged with the coils 7, lamination 3, lamination 5, and stator yoke 1. Both stamping piece 3 and stamping piece 5 have through holes in the vertical direction.
[0046] In one embodiment, the traveling wave magnetic field linear motor device of the control rod drive mechanism of this application can be used in the reactor control rod drive mechanism. In order to reduce the side effects of the radiation-containing and high-temperature coolant in the reactor on the coil, a sealing shell 2 is fixedly installed inside the lamination 1 3 and lamination 2 5. The sealing shell 2 is thin-walled cylindrical, and the length of the sealing shell 2 is greater than or equal to the straight-line distance between the upper lamination 1 3 and the lower lamination 1 3, so as to limit the heat exchange between the coolant and the coil 7 and the irradiation damage of the coil 7 by radioactive particles in the coolant.
[0047] In another embodiment, to make the linear motor modular, the thickness of the coil 7 and the lamination 2 5 remains unchanged. The number of coils 7 and lamination 2 5 is selected as needed, and multiple coils 7 can be set between two laminations 2 5 as required. This allows the linear motor to meet different usage requirements while reducing the difficulty of processing and manufacturing.
[0048] In another embodiment, to increase the output power of the linear motor and reduce its heat generation, the mover 9 includes an inner shielding shell 13, a guide rod 14, and an outer shielding shell 15. The guide rod 14 is a hollow rod, with a hollow cylindrical inner shielding shell 13 fixed inside and a hollow cylindrical outer shielding shell 15 fixed outside. The guide rod 14 is made of a metal with good magnetic permeability, such as silicon steel, iron-based amorphous alloy, iron-aluminum alloy pure iron, etc. Preferably, the material of the guide rod 14 is DT4E. Since the above materials have relatively poor corrosion resistance, they are prone to failure in the high temperature, high corrosion, and strong radiation environment of the reactor. Therefore, the inner shielding shell 13 and the outer shielding shell 15 are made of materials that are resistant to high temperature, corrosion, and radiation, such as austenitic stainless steel and martensitic stainless steel. Preferably, the materials of the inner shielding shell 13 and the outer shielding shell 15 are 12Cr13 or 304 stainless steel.
[0049] In another embodiment, in order to increase the magnetic permeability of the guide rod 14, a plurality of grooves 141 are formed on the outside of the guide rod 14 in the vertical direction. A magnetic ring 16 is provided in the groove 141. The magnetic ring 16 is made of the metal material with good magnetic permeability mentioned above. Preferably, the material of the magnetic ring 16 is DT4E.
[0050] In another embodiment, since the linear motor is in a high-temperature environment during reactor operation, in order to prevent the coil 7 from overheating and failing, the coil 7 is selected with a high-temperature resistant winding wire. Preferably, the coil 7 is selected with SBFG-2.55 high-temperature resistant winding wire.
[0051] In another embodiment, the side wall of the cylinder of the stator yoke 1 is provided with a slot 11 for the coil 7 to exit.
[0052] While those skilled in the art will recognize that the present invention is not limited to the details of the exemplary embodiments described above, and that it can be implemented in other specific forms without departing from the spirit or essential characteristics of the invention, the embodiments should be considered illustrative and non-limiting in all respects. The scope of the invention is defined by the appended claims rather than the foregoing description, and therefore all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the invention. No reference numerals in the claims should be construed as limiting the scope of the claims.
[0053] Furthermore, it should be understood that although the present invention is described according to embodiments, not every embodiment contains only one independent technical solution. This way of describing the specification is only for clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.
Claims
1. A design method for a traveling wave magnetic field linear motor with a control rod drive mechanism, characterized in that, Includes the following steps: S1. Determine the technical specifications, including lifting force and movement speed; S2. Based on the technical specifications determined in S1, determine the initial values of the main dimensions, the tooth groove dimensions, and the stator core yoke height. The initial values of the main dimensions include the total length of the motor, the inner diameter of the stator, the number of pole pairs, and the pole pitch. S3. Calculate the inner and outer diameters of the mover. Based on the tooth groove dimensions and stator core yoke height determined in S3, and the limitation imposed by the drive mechanism on the inner diameter of the mover hole, calculate the inner and outer diameters of the mover. S4. Given the initial value of the stator current density; S5. Determine the stator winding parameters, which include the number of turns, slot fill factor, and conductor diameter. S6. Determine whether the winding temperature rise meets the design requirements; S7. Determine whether the lifting force meets the design requirements; S8, optimization of the traveling wave magnetic field linear motor for the control rod drive mechanism.
2. The design method of the traveling wave magnetic field linear motor for the control rod drive mechanism according to claim 1, characterized in that, In step S6, the winding temperature rise is calculated and compared with the design requirements. If the design requirements are met, the next step is performed; if the design requirements are not met, the stator current density is changed, and steps S4-S6 are repeated until the winding temperature rise meets the design requirements.
3. The design method of the traveling wave magnetic field linear motor for the control rod drive mechanism according to claim 2, characterized in that, In step S7, the lifting force of the linear motor device is calculated based on its parameters and compared with the technical specifications. If the design requirements are met, the design parameters are output and the entire design process ends. If the design requirements are not met, the main dimensions given in step S2 are changed, and steps S3-S6 are repeated until the design requirements are met and the design process ends.
4. The design method of the traveling wave magnetic field linear motor for the control rod drive mechanism according to claim 3, characterized in that, S8 specifically includes the following steps: S801. Select optimization variables based on the design dimensions of the linear motor; S802. Set the variable domain to determine the range of values for the optimization variables; S803, Define the objective function; S804, Finite Element Simulation; S805, Calculate fitness; S806, The optimal solution is obtained.
5. The design method of the traveling wave magnetic field linear motor for the control rod drive mechanism according to claim 4, characterized in that, In step S801, the selection of optimization variables needs to meet two conditions: Condition 1: The optimization variables should be selected from the design parameters that have a significant impact on the objective function; Condition 2: These design parameters are relatively independent.
6. The design method of the traveling wave magnetic field linear motor for the control rod drive mechanism according to claim 5, characterized in that, In step S803, the average thrust of the motor, the thrust fluctuation rate, and the weight of the motor mover are selected and a weighted objective function is constructed. The objective function is defined as follows: ; where r i (i=1~4) represents the rate of change, defined as follows: Where x represents the selected optimization variable, F z0 Fluctuation0 and Weight0 correspond to the axial electromagnetic thrust, thrust fluctuation rate, and weight of the linear motor before optimization under constant current control conditions, respectively; F z1 Fluctuation1 and Weight1 represent the optimized axial electromagnetic thrust, thrust fluctuation rate, and motor weight of the linear motor; k is selected. i (i=1~3) are the weight coefficients of the optimization objective. Different weight coefficients are selected for optimization according to different needs.
7. The design method of the traveling wave magnetic field linear motor for the control rod drive mechanism according to claim 6, characterized in that, In step S805, the optimization results of the average thrust of the motor and the weight of the motor mover are superimposed according to the objective function to obtain the optimization process of the effective thrust of the motor.
8. The design method of the traveling wave magnetic field linear motor for the control rod drive mechanism according to claim 7, characterized in that, In step S806, after obtaining the optimization result, the design parameters of the optimization scheme are rounded to ensure that the design scheme meets the processing requirements.
9. A control rod drive mechanism for a traveling wave magnetic field linear motor, characterized in that, The device includes a stator assembly and a mover, which are slidably connected vertically. The stator assembly includes a stator yoke, a sealing shell, a first lamination, a housing, a second lamination, an elastic retaining ring, and coils. The stator yoke is fixedly installed inside the housing. The stator yoke is hollow cylindrical in shape, with an annular mounting groove on the upper and lower inner walls. The mounting grooves are fixedly connected to the elastic retaining rings. A first lamination is fixedly installed on the lower part of the upper elastic retaining ring and the upper part of the lower elastic retaining ring, respectively. Multiple coils are evenly distributed between the two first laminations along the axis of the stator yoke, forming a coil group. Two adjacent coils are separated by a second lamination. The sealing shell is coaxially arranged with the coils, first lamination, second lamination, and stator yoke. Both first and second laminations have through holes in the vertical direction.
10. The control rod drive mechanism traveling wave magnetic field linear motor device according to claim 9, characterized in that, The mover includes an inner shielding shell, a guide rod, and an outer shielding shell. The guide rod is a hollow rod with a hollow cylindrical inner shielding shell fixed inside and a hollow cylindrical outer shielding shell fixed outside. Multiple slots are formed on the outer side of the guide rod along the vertical direction, and magnetic rings are placed in the slots. The guide rod is made of silicon steel, iron-based amorphous alloy, or iron-aluminum alloy pure iron. The inner and outer shielding shells are made of austenitic stainless steel or martensitic stainless steel. The magnetic rings are made of DT4E.