A bistable permanent magnet operating mechanism and its key magnetic circuit parameter co-optimization method

Abstract

This application provides a bistable permanent magnet operating mechanism and a method for co-optimizing its key magnetic circuit parameters, relating to the technical field of operating mechanisms for switchgear. The mechanism includes: a moving iron core, a moving iron core magnetic shielding sheet disposed on the outer periphery of the moving iron core, a stationary iron core sleeved on the outside of the moving iron core, and a first electromagnetic assembly, a stationary iron core magnetic shielding sheet, and a second electromagnetic assembly embedded in the internal cavity of the stationary iron core and arranged along the axial direction of the moving iron core; the first electromagnetic assembly and the second electromagnetic assembly surround the outer periphery of the moving iron core and are respectively disposed on both sides of the stationary iron core magnetic shielding sheet; the first electromagnetic assembly includes a first permanent magnet and a closing coil disposed on the axial outer side of the first permanent magnet; the second electromagnetic assembly includes a second permanent magnet and a opening coil disposed on the axial outer side of the second permanent magnet.

Description

Technical Field

[0001] This application relates to the field of operating mechanism technology for switchgear, and more specifically, to a bistable permanent magnet operating mechanism and a method for collaborative optimization of its key magnetic circuit parameters. Background Technology

[0002] Bistable permanent magnet operating mechanisms, as important actuators in switchgear, are widely used in the opening and closing control of circuit breakers, contactors, and other devices. These mechanisms typically utilize permanent magnets to provide holding force in both the open and closed positions, achieving instantaneous actuation through opening and closing coils, thus balancing the requirements of low holding power consumption and rapid response. With the increasing demands for high-frequency operation, low-energy holding, consistent action, and compact structure in power distribution systems, the overall performance of bistable permanent magnet operating mechanisms in engineering applications is receiving increasing attention. Summary of the Invention

[0003] In view of this, this application provides a bistable permanent magnet operating mechanism and a method for collaborative optimization of its key magnetic circuit parameters.

[0004] One aspect of this application provides a bistable permanent magnet operating mechanism, comprising: a moving iron core, a moving iron core magnetic shielding sheet disposed on the outer periphery of the moving iron core, a stationary iron core sleeved on the outer side of the moving iron core, and a first electromagnetic component, a stationary iron core magnetic shielding sheet, and a second electromagnetic component embedded in the internal cavity of the stationary iron core and arranged along the axial direction of the moving iron core; the first electromagnetic component and the second electromagnetic component surround the outer periphery of the moving iron core and are respectively disposed on both sides of the stationary iron core magnetic shielding sheet; the first electromagnetic component includes a first permanent magnet and a closing coil disposed on the axial outer side of the first permanent magnet; the second electromagnetic component includes a second permanent magnet and a opening coil disposed on the axial outer side of the second permanent magnet; wherein, using the parameters of the stationary iron core magnetic shielding sheet, the parameters of the moving iron core magnetic shielding sheet, the volume ratio of the first permanent magnet and the second permanent magnet, and the working air gap as a combination of variables to be optimized, the value of the combination of variables to be optimized is determined by constructing an objective function characterizing the coupling degree, magnetic flux utilization rate, and steady-state holding capability.

[0005] According to an embodiment of this application, the first permanent magnet includes a first left permanent magnet and a first right permanent magnet; the second permanent magnet includes a second left permanent magnet and a second right permanent magnet; the end face of the first left permanent magnet is opposite to the end face of the first right permanent magnet; and the end face of the second left permanent magnet is opposite to the end face of the second right permanent magnet.

[0006] Another aspect of this application provides a method for collaborative optimization of key magnetic circuit parameters of a bistable permanent magnet operating mechanism, applied to the aforementioned bistable permanent magnet operating mechanism. The method includes: using the parameters of the stationary core magnetic shield, the parameters of the moving core magnetic shield, the volume ratio of the first permanent magnet and the second permanent magnet, and the working air gap as combinations of variables to be optimized, determining the opening holding force, closing holding force, coupling coefficient, and flux utilization rate of the bistable permanent magnet operating mechanism corresponding to the aforementioned combination of variables; constructing an objective function characterizing the coupling degree, flux utilization rate, and steady-state holding capability based on the aforementioned opening holding force, closing holding force, coupling coefficient, and flux utilization rate; and determining the optimal solution of the aforementioned combination of variables to be optimized based on the aforementioned objective function, thereby obtaining the key magnetic circuit parameters of the aforementioned bistable permanent magnet operating mechanism.

[0007] According to an embodiment of this application, the objective function is as follows: ;in, Combination of variables to be optimized The objective function; For the tripping holding force; For closing holding force; The coupling coefficient; For magnetic flux utilization; The minimum holding force required to maintain the tripped circuit breaker; The minimum holding force required to maintain the circuit breaker position during closing; , , These are the weighting coefficients.

[0008] According to an embodiment of this application, determining the optimal solution of the above-mentioned combination of variables to be optimized based on the above-mentioned objective function includes: generating multiple initial parameter combinations based on the boundaries of each parameter in the above-mentioned combination of variables to be optimized; determining an individual optimal parameter combination and a global optimal parameter combination based on the function value of the above-mentioned objective function corresponding to each initial parameter combination; updating the multiple initial parameter combinations based on the individual optimal parameter combination, the global optimal parameter combination, the inertia weight, the individual learning factor, and the group learning factor; using the updated initial parameter combination as the above-mentioned initial parameter combination, repeatedly performing the operation of determining the individual optimal parameter combination and the global optimal parameter combination, as well as the operation of updating the multiple initial parameter combinations, until a preset iteration condition is reached; and determining the key magnetic circuit parameters of the above-mentioned bistable permanent magnet operating mechanism based on the global optimal parameter combination obtained when the preset iteration condition is reached.

[0009] According to an embodiment of this application, in the case of determining the individual optimal parameter combination and the global optimal parameter combination for the first time, the individual optimal parameter combination and the global optimal parameter combination are determined based on the function value of the objective function corresponding to each initial parameter combination, including: taking each of the initial parameter combinations as its own individual optimal parameter combination, and determining the individual optimal parameter combination with the smallest function value from the multiple individual optimal parameter combinations as the global optimal parameter combination.

[0010] According to an embodiment of this application, in the case of repeatedly executing the determination of individual optimal parameter combinations and global optimal parameter combinations, determining individual optimal parameter combinations and global optimal parameter combinations based on the function value of the objective function corresponding to each initial parameter combination includes: for any initial parameter combination, if the function value corresponding to the initial parameter combination at the current iteration number is less than the function value corresponding to the individual optimal parameter combination, the initial parameter combination at the current iteration number is taken as the individual optimal parameter combination; the function values ​​corresponding to multiple individual optimal parameter combinations at the current iteration number are compared with the function value corresponding to the global optimal parameter combination at the current iteration number; if the comparison result indicates that the function value corresponding to the individual optimal parameter combination at the current iteration number is less than the function value corresponding to the global optimal parameter combination at the current iteration number, the individual optimal parameter combination at the current iteration number is taken as the global optimal parameter combination, thereby updating the global optimal parameter combination at the current iteration number.

[0011] According to an embodiment of this application, updating multiple initial parameter combinations based on the aforementioned individual optimal parameter combination, the aforementioned global optimal parameter combination, the aforementioned inertia weight, the individual learning factor, and the group learning factor includes: determining the update adjustment amount for each of the aforementioned initial parameter combinations based on the aforementioned individual optimal parameter combination, the aforementioned global optimal parameter combination, the aforementioned inertia weight, the individual learning factor, and the group learning factor; and updating multiple of the aforementioned initial parameter combinations based on the aforementioned update adjustment amount.

[0012] According to the embodiments of this application, the formula for determining the update adjustment amount for each of the above-mentioned initial parameter combinations is as follows: ;in, This represents the update adjustment amount for the i-th initial parameter combination in the (r+1)-th iteration; For inertial weights, For individual learning factors; For group learning factors; and All are intervals Random numbers within; For the first The initial parameter combination in the th... The optimal combination of parameters for each individual in the next iteration. The optimal combination of parameters globally; This represents the update adjustment amount for the i-th initial parameter combination in the r-th iteration; For the first The initial parameter combination in the th... The updated initial parameter combination obtained in the next iteration.

[0013] According to an embodiment of this application, the formula for the above coupling coefficient is: The formula for the above magnetic flux utilization rate is: ;in, The coupling coefficient; For magnetic flux utilization; The total magnetic flux of the coil excitation. For the coupling magnetic flux to enter the working magnetic circuit on the other side, The effective magnetic flux to enter the target working magnetic circuit.

[0014] According to the embodiments of this application, by setting a moving iron core magnetic shielding sheet at the corresponding position of the moving iron core, setting a stationary iron core magnetic shielding sheet at the corresponding position of the stationary iron core, and setting a first permanent magnet and a second permanent magnet, a local high magnetic reluctance region is constructed; in the open holding state and the close holding state, the permanent magnet flux forms a stable holding force along different main closed paths respectively; during the coil excitation operation, the stationary iron core magnetic shielding sheet and the moving iron core magnetic shielding sheet raise the local magnetic reluctance, so that the excitation flux preferentially closes through the middle stationary iron core and the upper and lower blocks of the first permanent magnet and the second permanent magnet region, thereby weakening the magnetic circuit coupling between the open coil and the close coil, improving the coil magnetic flux utilization rate, reducing magnetic circuit loss, and improving the opening and closing operation characteristics of the mechanism. Furthermore, regarding the parameters of the stationary iron core magnetic shielding sheet, the parameters of the moving iron core magnetic shielding sheet, the parameters of the first permanent magnet block, the parameters of the second permanent magnet block, and the coupling relationship between the working air gap, the above-mentioned key magnetic circuit parameters of the bistable permanent magnet operating mechanism are determined by constructing an objective function characterizing the steady-state holding capability, coupling degree, and magnetic flux utilization rate, thereby improving the overall performance and control stability of the bistable permanent magnet operating mechanism. Attached Figure Description

[0015] The above and other objects, features and advantages of this application will become clearer from the following description of embodiments with reference to the accompanying drawings, in which:

[0016] Figure 1 The schematic diagram illustrates the magnetic field distribution of the bistable permanent magnet operating mechanism in the open holding state according to an embodiment of this application.

[0017] Figure 2 The schematic diagram illustrates a simulation of the magnetic field distribution in the open-hold state of a bistable permanent magnet operating mechanism according to an embodiment of this application.

[0018] Figure 3 The schematic diagram illustrates the magnetic field distribution during the initial closing process of a bistable permanent magnet operating mechanism according to an embodiment of this application.

[0019] Figure 4 The diagram illustrates a simulation of the magnetic field distribution during the initial closing process of a bistable permanent magnet operating mechanism according to an embodiment of this application.

[0020] Figure 5 The schematic diagram illustrates the magnetic field distribution of the bistable permanent magnet operating mechanism in the closing holding state according to an embodiment of this application.

[0021] Figure 6 The schematic diagram illustrates a simulation of the magnetic field distribution in the closing holding state of a bistable permanent magnet operating mechanism according to an embodiment of this application.

[0022] Figure 7 The schematic diagram illustrates the magnetic field distribution during the initial opening process of the bistable permanent magnet operating mechanism according to an embodiment of this application.

[0023] Figure 8 The diagram illustrates a simulation of the magnetic field distribution during the initial opening process of a bistable permanent magnet operating mechanism according to an embodiment of this application.

[0024] Figure 9 A flowchart illustrating a method for collaborative optimization of key magnetic circuit parameters of a bistable permanent magnet operating mechanism according to an embodiment of this application is shown.

[0025] Figure 10 A flowchart illustrating a method for collaborative optimization of key magnetic circuit parameters based on particle swarm optimization according to an embodiment of this application is shown.

[0026] Explanation of reference numerals in the attached diagram:

[0027] 1. Opening coil; 2. Magnetic shielding sheet of stationary iron core; 3. Closing coil; 4. Closing working air gap; 5. Magnetic shielding sheet of moving iron core; 6. Opening working air gap; 7. First permanent magnet; 8. Second permanent magnet; 9. Stationary iron core; 10. Moving iron core. Detailed Implementation

[0028] The embodiments of this application will now be described with reference to the accompanying drawings. However, it should be understood that these descriptions are exemplary only and are not intended to limit the scope of this application. In the following detailed description, numerous specific details are set forth to provide a thorough understanding of the embodiments of this application for ease of explanation. However, it will be apparent that one or more embodiments may be implemented without these specific details. Furthermore, descriptions of well-known structures and technologies are omitted in the following description to avoid unnecessarily obscuring the concepts of this application.

[0029] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of this application. The terms "comprising," "including," etc., as used herein indicate the presence of the above-described features, steps, operations, and / or components, but do not exclude the presence or addition of one or more other features, steps, operations, or components.

[0030] All terms used herein (including technical and scientific terms) have the meanings commonly understood by those skilled in the art, unless otherwise defined. It should be noted that the terms used herein are to be interpreted in a manner consistent with the context of this specification, and not in an idealized or overly rigid way.

[0031] When using expressions such as "at least one of A, B and C", they should generally be interpreted in accordance with the meaning that is commonly understood by those skilled in the art (e.g., "a system having at least one of A, B and C" should include, but is not limited to, a system having A alone, a system having B alone, a system having C alone, a system having A and B, a system having A and C, a system having B and C, and / or a system having A, B and C, etc.).

[0032] In the embodiments of this application, the collection, updating, analysis, processing, use, transmission, provision, disclosure, and storage of data (e.g., including but not limited to user personal information) comply with relevant laws and regulations, are used for legitimate purposes, and do not violate public order and good morals. In particular, necessary measures have been taken to prevent unauthorized access to user personal information data and to safeguard user personal information security, network security, and national security.

[0033] Existing bistable permanent magnet operating mechanisms still have several common shortcomings in terms of magnetic circuit configuration, steady-state maintenance, and parameter matching, which can easily lead to the following three typical problems in practical design and application:

[0034] 1. Problems with magnetic circuit coupling and insufficient utilization of excitation flux during the opening and closing operation phases. In existing bistable permanent magnet operating mechanisms, the opening and closing coils often share a certain degree of magnetic circuit relationship in their structure. When one coil is energized, some magnetic flux easily enters the working magnetic circuit of the other side, forming ineffective linkages and magnetic circuit coupling, resulting in the excitation flux generated by the coil not being sufficiently concentrated on the target drive path. This phenomenon not only weakens the effective electromagnetic driving force but also increases magnetic circuit losses, affecting the consistency and response speed of the opening and closing actions. Especially in the initial stage of the operation, if the magnetic flux closing path lacks clear guidance, the excitation flux is more likely to disperse along non-target paths, thereby reducing the dynamic drive performance of the mechanism.

[0035] 2. Problems with uneven permanent magnet flux distribution and insufficient coordination of holding characteristics in bistable holding states. Bistable permanent magnet operating mechanisms require the establishment of stable permanent magnet holding circuits in both the open and closed positions to ensure sufficient holding capability in both steady states. However, in existing structures, the arrangement of permanent magnets, the relationship between the moving and stationary iron cores, and the air gap conditions at the upper and lower end faces often lack targeted coordinated design. This can easily lead to an uneven distribution of permanent magnet flux in the open and closed holding states, resulting in differences in holding capability between the two steady states. This lack of coordination in holding capability not only affects the steady-state reliability of the mechanism but may also adversely impact the mechanical response during the release and re-engagement processes, reducing the overall operational quality of the bistable mechanism.

[0036] 3. The lack of unified matching among key magnetic circuit parameters makes it difficult to balance holding and operating performance. The overall performance of a bistable permanent magnet operating mechanism is not determined by a single structural dimension, but is influenced by multiple key parameters, such as the size and location of local high reluctance structures, the size distribution of different regions of the permanent magnet, and the relative relationship between the opening and closing working air gaps. These parameters exhibit significant nonlinear coupling characteristics: changes in local structural parameters affect the magnetic flux closure path, permanent magnet distribution parameters affect the holding force levels of the two steady states, and the working air gap parameters further affect the establishment process of the main magnetic circuit reluctance and excitation flux during the operating phase. Existing design methods often rely on empirical selection, local trial and error, or single-parameter adjustments, lacking a unified design approach oriented towards holding capability, coupling suppression capability, and magnetic flux utilization. Therefore, it is difficult to fully leverage the potential advantages of bistable permanent magnet operating mechanisms in low-power holding and rapid operation.

[0037] In summary, existing bistable permanent magnet operating mechanisms still have room for improvement in terms of magnetic circuit coupling control during the operation phase, bistable holding magnetic circuit construction, and key parameter coordination and matching. Therefore, it is necessary to propose a new magnetic circuit design scheme that can take into account reliable holding of opening and closing, directional closure of excitation flux, and comprehensive performance optimization, so as to improve the operating mechanism's operating efficiency, control stability, and engineering applicability.

[0038] Based on this, embodiments of this application provide a bistable permanent magnet operating mechanism, including: a moving iron core, a moving iron core magnetic shielding sheet disposed on the outer periphery of the moving iron core, a stationary iron core sleeved on the outside of the moving iron core, and a first electromagnetic component, a stationary iron core magnetic shielding sheet, and a second electromagnetic component embedded in the internal cavity of the stationary iron core and arranged along the axial direction of the moving iron core; the first electromagnetic component and the second electromagnetic component surround the outer periphery of the moving iron core and are respectively disposed on both sides of the stationary iron core magnetic shielding sheet; the first electromagnetic component includes a first permanent magnet and a closing coil disposed on the axial outer side of the first permanent magnet; the second electromagnetic component includes a second permanent magnet and a opening coil disposed on the axial outer side of the second permanent magnet; wherein, the parameters of the stationary iron core magnetic shielding sheet, the parameters of the moving iron core magnetic shielding sheet, the volume ratio of the first permanent magnet and the second permanent magnet, and the working air gap are used as the combination of variables to be optimized, and the value of the combination of variables to be optimized is determined by constructing an objective function characterizing the coupling degree, magnetic flux utilization rate, and steady-state holding capability.

[0039] In the embodiments of this application, the bistable permanent magnet operating mechanism can be used for the opening and closing drive and status maintenance of switching electrical appliances such as circuit breakers and contactors.

[0040] Applications below Figures 1-8 The magnetic field distribution corresponding to each working state of the bistable permanent magnet operating mechanism provided in the embodiments of this application is described to deepen the understanding of the bistable permanent magnet operating mechanism provided in the embodiments of this application.

[0041] like Figure 1 As shown, the first permanent magnet 7 includes a first left permanent magnet and a first right permanent magnet; the second permanent magnet 8 includes a second left permanent magnet and a second right permanent magnet; the end face of the first left permanent magnet is opposite to the end face of the first right permanent magnet; the end face of the second left permanent magnet is opposite to the end face of the second right permanent magnet.

[0042] The permanent magnets on each side are divided into two parts, upper and lower. The permanent magnets on the left side are divided into the first left permanent magnet and the second left permanent magnet; the permanent magnets on the right side are divided into the first right permanent magnet and the second right permanent magnet.

[0043] When the bistable permanent magnet operating mechanism is in the open-hold state, the moving iron core 10 is in the open-hold position, and the magnetic field within the bistable permanent magnet operating mechanism consists only of permanent magnet flux. Since neither the opening coil 1 nor the closing coil 3 is energized, neither the opening coil 1 nor the closing coil 3 generates a magnetic field. At this time, the bistable permanent magnet operating mechanism is in a steady-state position, and the magnetic flux closes through the minimum path. The moving iron core is in an extreme position, that is, the opening working air gap 6 between the lower end face of the moving iron core and the stationary iron core is the smallest, and the closing working air gap 4 between the upper end face of the moving iron core and the stationary iron core is the largest.

[0044] like Figure 2 As shown, the magnetic flux flow direction of the first permanent magnet 7 and the second permanent magnet 8 is... Figure 1The theoretical analysis shown is basically consistent. Since the air gap at the lower end face of the moving iron core 10 is much smaller than that at the upper end face, the permanent magnet flux mainly passes through the lower end face of the moving iron core 10 to provide permanent magnet force for maintaining the steady state of the mechanism.

[0045] exist Figure 3 When current is supplied to the closing coil 3, the magnetic flux generated by the coil will preferentially close through the path of least magnetic resistance due to the principle of minimum magnetic resistance. At this time, since the magnetic shielding sheet 2 of the stationary iron core 9 is inserted inside the stationary iron core 9, the magnetic flux of the closing coil 3 will close through the middle of the stationary iron core 9. The closed path of the lower end face of the moving iron core 10 will be affected by the magnetic shielding sheet 5 of the moving iron core, which will increase the magnetic resistance of the closed path, thereby reducing the part of the coil magnetic flux that closes from the lower end face, and improving the coil coupling phenomenon caused by the shared magnetic circuit.

[0046] like Figure 4 The simulation diagram shows that when current is supplied to the closing coil 3, the closing coil 3 generates an electromagnetic force that drives the closing mechanism. Because the stationary iron core 9 has a stationary iron core magnetic shield 2, and the moving iron core 10 has a moving iron core magnetic shield 5, if the coil flux were to pass through the lower end of the moving iron core 10 to form coupling, the magnetic reluctance would be very high. Therefore, the coil flux instead passes through two permanent magnets (one on the left and one on the right) and two permanent magnets (one on the right and one on the right), and then through the middle stationary iron core 9 region to form coupling. This not only reduces the coupling between the opening coil 1 and the closing coil 3, but also reduces the path the flux takes, improving the utilization rate of the coil flux and reducing magnetic circuit losses. Figure 4 The simulation diagram shown indicates the direction of magnetic flux flow in the coil. Figure 3 The working principle analysis shown is basically consistent, which verifies the feasibility of the mechanism.

[0047] Figure 5 The schematic diagram illustrates the magnetic field distribution of the bistable permanent magnet operating mechanism in the closing holding state according to an embodiment of this application.

[0048] like Figure 5 As shown, when the relative positions of the moving iron core 10 and the stationary iron core 9 are in the steady-state position of closing, the magnetic flux of the first permanent magnet 7 and the second permanent magnet 8 in both the upper and lower parts closes through the path on the upper end face of the moving iron core 10, providing attraction for the closing holding state. When the moving iron core is in another extreme position, that is, the opening working air gap 6 between the lower end face of the moving iron core and the stationary iron core is at its maximum, and the closing working air gap 4 between the upper end face of the moving iron core and the stationary iron core is at its minimum. Therefore, the minimum value of the closing working air gap 4 is consistent with the minimum value of the opening working air gap 6; the maximum value of the closing working air gap 4 is consistent with the maximum value of the opening working air gap 6.

[0049] In the closed-hold state of the bistable permanent magnet operating mechanism, since neither the opening coil 1 nor the closing coil 3 is energized, the bistable permanent magnet operating mechanism maintains its steady state solely by the attraction provided by the first permanent magnet 7 and the second permanent magnet 8. Therefore, only the magnetic field lines of the permanent magnets are distributed within the bistable permanent magnet operating mechanism. Figure 6 As can be seen from the diagram, the magnetic flux of the first left permanent magnet and the second left permanent magnet mainly passes through the upper and lower permanent magnets and the middle stationary iron core 9, and almost does not pass through the magnetic circuit part between the lower end face of the moving iron core 10 and the trip coil 1. The magnetic flux direction is similar to... Figure 5 The working principle analysis shown is consistent with the results.

[0050] like Figure 7 As shown, when current is supplied to the trip coil 1, the magnetic flux generated by the trip coil 1 will, due to the action of the moving iron core magnetic shield 5 and the stationary iron core magnetic shield 2, avoid closing through the upper end face of the moving iron core 10. Instead, it will close through the upper and lower permanent magnets composed of the first left permanent magnet and the second left permanent magnet and the middle part of the stationary iron core 9, as well as the upper and lower permanent magnets composed of the first right permanent magnet and the second right permanent magnet and the middle part of the stationary iron core 9. This reduces the coupling phenomenon between the trip coil 1 and the closing coil 3, improves the magnetic flux utilization rate of the coil, and improves the operating characteristics of the mechanism.

[0051] like Figure 8 As shown, the moving iron core 10 is still in the closed holding state. An excitation current is supplied to the opening coil 1, generating magnetic flux for opening. Because the magnetic isolation sheet 2 and the moving iron core magnetic isolation sheet 5 of the stationary iron core have much greater magnetic resistance than other magnetic circuits, most of the magnetic flux in the opening coil 1 is closed by the upper and lower permanent magnets formed by the first and second left permanent magnets and the stationary iron core 9 in the middle, as well as by the upper and lower permanent magnets formed by the first and second right permanent magnets and the stationary iron core 9 in the middle. This greatly improves the magnetic flux conversion efficiency of the coil, while reducing the magnetic flux coupling portion of the coil, reducing magnetic circuit losses, and improving the operating characteristics of the mechanism.

[0052] This application proposes a flux guiding and coupling suppression structure based on dual magnetic isolation sheets on the moving and stationary iron cores. Addressing the problems in bistable permanent magnet operating mechanisms where the opening and closing coils share a magnetic circuit, and the excitation flux easily enters the non-target working magnetic circuit during the initial stage of operation, leading to ineffective linkages and magnetic circuit coupling, magnetic isolation sheets are placed at corresponding positions on the moving and stationary iron cores to construct locally high magnetic reluctance regions. During coil excitation, by raising the magnetic reluctance of the existing coupled closed path, the excitation flux generated by the opening and closing coils preferentially closes along the central stationary iron core and the target working magnetic circuit, thereby reducing mutual interference between the opening and closing magnetic circuits, improving coil flux utilization, reducing magnetic circuit losses, and improving the response performance and control stability of the mechanism during opening and closing operations.

[0053] The embodiments of this application first design a bistable permanent magnet holding structure with upper and lower segmented permanent magnets and a symmetrical magnetic circuit. The first electromagnetic component and the second electromagnetic component are symmetrical along the plane containing the axial midpoint of the stationary iron core 9. Since the bistable permanent magnet operating mechanism is designed to be symmetrical, the closing holding state and the opening holding state are also symmetrically distributed. Then, using the parameters of the stationary iron core magnetic shielding sheet, the parameters of the moving iron core magnetic shielding sheet, the volume ratio of the first permanent magnet and the second permanent magnet, and the working air gap as the combination of variables to be optimized, by constructing an objective function characterizing the coupling degree, magnetic flux utilization rate, and steady-state holding capability, the value of the combination of variables to be optimized is determined, thereby adjusting the parameters of the bistable permanent magnet holding structure and obtaining a bistable permanent magnet holding structure with better parameters.

[0054] To address the issues of uneven permanent magnet flux distribution and insufficient coordination between the two steady-state holding capabilities in existing bistable permanent magnet operating mechanisms during the open and closed holding states, this paper proposes an upper and lower segmented permanent magnet design on both sides of the mechanism. Combined with the magnetic circuit structure of these segmented permanent magnets, the permanent magnet flux in the open holding state primarily closes through the corresponding path on the lower end face of the moving iron core, while in the closed holding state, it primarily closes through the corresponding path on the upper end face of the moving iron core. This establishes stable permanent magnet holding magnetic circuits in both steady-state positions. This structure can reliably maintain the open and closed states without relying on continuous coil energization, balancing low-power holding requirements with the consistency requirements of bistable operation.

[0055] According to the embodiments of this application, firstly, by introducing magnetic shielding sheets at corresponding positions of the moving iron core and the stationary iron core, a local high magnetic reluctance region is constructed, thereby achieving active control of the excitation flux closed path and effectively suppressing the magnetic circuit coupling between the opening coil and the closing coil. Simultaneously, by setting upper and lower segmented permanent magnets on both sides of the bistable permanent magnet operating mechanism, and combining the air gap difference between the upper and lower end faces of the moving iron core, stable and independent permanent magnet holding magnetic circuits are established in both the opening and closing holding states. Based on this, since there is a significant nonlinear coupling relationship between the parameters of the moving iron core magnetic shielding sheet, the parameters of the stationary iron core magnetic shielding sheet, the segmentation ratio of the first left permanent magnet to the second left permanent magnet (or the segmentation ratio of the first right permanent magnet to the second right permanent magnet), and the working air gap, relying solely on empirical design is insufficient to simultaneously consider magnetic circuit coupling suppression, flux utilization, and bistable holding capability. Therefore, it is necessary to perform collaborative optimization design of key magnetic circuit parameters.

[0056] To this end, this application also proposes a method for co-optimizing key magnetic circuit parameters of a bistable permanent magnet operating mechanism. The method uses the structural parameters of the moving iron core magnetic shielding sheet, the structural parameters of the stationary iron core magnetic shielding sheet, the block ratio of the first left permanent magnet to the second left permanent magnet (or the block ratio of the first right permanent magnet to the second right permanent magnet), and the working air gap as joint optimization variables. By constructing a comprehensive objective function that includes coupling degree, magnetic flux utilization rate, and bistable state maintenance capability, the parameter space is iteratively optimized to obtain a parameter combination with coordinated optimization of multiple performance indicators. While ensuring reliable bistable state maintenance, this method further reduces the coupling of the opening and closing coils, improves magnetic flux utilization efficiency, and enhances the dynamic response performance of the mechanism.

[0057] Figure 9 A flowchart illustrating a method for collaborative optimization of key magnetic circuit parameters of a bistable permanent magnet operating mechanism according to an embodiment of this application is shown.

[0058] like Figure 9 As shown, the key magnetic circuit parameter co-optimization method of the bistable permanent magnet operating mechanism includes operations S901 to S903.

[0059] In operation S901, the parameters of the stationary iron core magnetic shielding sheet, the parameters of the moving iron core magnetic shielding sheet, the volume ratio of the first permanent magnet and the second permanent magnet, and the working air gap are used as the combination of variables to be optimized to determine the opening holding force, closing holding force, coupling coefficient, and magnetic flux utilization rate of the bistable permanent magnet operating mechanism corresponding to the combination of variables to be optimized.

[0060] In the embodiments of this application, when the first permanent magnet includes a first left permanent magnet and a first right permanent magnet, and the second permanent magnet includes a second left permanent magnet and a second right permanent magnet, the volume ratio of the first permanent magnet and the second permanent magnet represents the volume ratio of the first left permanent magnet and the second left permanent magnet or the volume ratio of the first right permanent magnet and the second right permanent magnet.

[0061] The working air gap includes the closing working air gap and the opening working air gap. The maximum value of the closing working air gap is the same as the maximum value of the opening working air gap, and the minimum value of the closing working air gap is the same as the minimum value of the opening working air gap.

[0062] In operating S902, an objective function characterizing the degree of coupling, flux utilization, and steady-state holding capability is constructed based on the opening holding force, closing holding force, coupling coefficient, and flux utilization.

[0063] In operation S903, the optimal solution of the combination of variables to be optimized is determined according to the objective function, so as to obtain the key magnetic circuit parameters of the bistable permanent magnet operating mechanism.

[0064] By adjusting the values ​​of each parameter in the combination of variables to be optimized, the opening holding force, closing holding force, coupling coefficient, and magnetic flux utilization rate corresponding to the combination of variables to be optimized under different values ​​are obtained, and thus different function values ​​of the objective function are obtained. From multiple function values, the value of each parameter of the combination of variables to be optimized that achieves a balance between reducing coil coupling, improving magnetic flux utilization rate, and maintaining bistable holding capability is determined, and thus the optimal value of each parameter of the combination of variables to be optimized is obtained, which is the optimal solution of the combination of variables to be optimized. Each parameter in the combination of variables to be optimized is the key magnetic circuit parameter of the bistable permanent magnet operating mechanism.

[0065] According to an embodiment of this application, in operation S903, the optimal solution of the combination of variables to be optimized is determined according to the objective function, including operations S9031 to S9035.

[0066] In operation S9031, multiple initial parameter combinations are generated based on the boundaries of each parameter in the combination of variables to be optimized.

[0067] In the embodiments of this application, multiple values ​​can be randomly generated for each parameter based on the boundaries of each parameter in the combination of variables to be optimized; each initial parameter combination includes the same number of parameters; at least some parameters in different initial parameter combinations have different values.

[0068] In operation S9032, the individual optimal parameter combination and the global optimal parameter combination are determined based on the function value of the objective function corresponding to each initial parameter combination.

[0069] According to an embodiment of this application, in operation S9032, when determining the individual optimal parameter combination and the global optimal parameter combination for the first time, the individual optimal parameter combination and the global optimal parameter combination are determined based on the function value of the objective function corresponding to each initial parameter combination, including: taking each initial parameter combination as its own individual optimal parameter combination, and determining the individual optimal parameter combination with the smallest function value from multiple individual optimal parameter combinations as the global optimal parameter combination.

[0070] In the process of determining the individual optimal parameter combination and the global optimal parameter combination through multiple executions, the individual optimal parameter combination and the global optimal parameter combination are determined based on the function value of the objective function corresponding to each initial parameter combination. This includes: for any initial parameter combination, if the function value corresponding to the initial parameter combination in the current iteration number is less than the function value corresponding to the individual optimal parameter combination, the initial parameter combination in the current iteration number is used as the individual optimal parameter combination. The function values ​​corresponding to multiple individual optimal parameter combinations in the current iteration number are compared with the function value corresponding to the global optimal parameter combination in the current iteration number. If the comparison result indicates that the function value corresponding to the individual optimal parameter combination in the current iteration number is less than the function value corresponding to the global optimal parameter combination in the current iteration number, the individual optimal parameter combination in the current iteration number is used as the global optimal parameter combination to update the global optimal parameter combination in the current iteration number.

[0071] If the function value corresponding to the individual optimal parameter combination is greater than or equal to the function value corresponding to the global optimal parameter combination under the current repetition count, the global optimal parameter combination under the current repetition count remains unchanged.

[0072] In operation S9033, multiple initial parameter combinations are updated based on individual optimal parameter combinations, global optimal parameter combinations, inertia weights, individual learning factors, and group learning factors.

[0073] According to an embodiment of this application, in operation S9033, updating multiple initial parameter combinations based on the individual optimal parameter combination, the global optimal parameter combination, the inertia weight, the individual learning factor, and the group learning factor includes: determining the update adjustment amount of each initial parameter combination based on the individual optimal parameter combination, the global optimal parameter combination, the inertia weight, the individual learning factor, and the group learning factor; and updating multiple initial parameter combinations based on the update adjustment amount.

[0074] In operation S9034, the updated initial parameter combination is used as the initial parameter combination. The operation of determining the individual optimal parameter combination and the global optimal parameter combination, as well as the operation of updating multiple initial parameter combinations, are repeatedly executed until the preset iteration condition is reached.

[0075] In the embodiments of this application, the updated initial parameter combination is used as the initial parameter combination, which is the current parameter combination for the next iteration, and operations S9032~S9034 are repeatedly executed until the preset iteration condition is reached.

[0076] When operating S9035, the key magnetic circuit parameters of the bistable permanent magnet operating mechanism are determined based on the globally optimal parameter combination obtained when the preset iteration conditions are met.

[0077] Figure 10 A flowchart illustrating a method for collaborative optimization of key magnetic circuit parameters based on particle swarm optimization according to an embodiment of this application is shown.

[0078] like Figure 10 As shown, the joint optimization variables act on the formation of the local high magnetic reluctance region, the magnetic flux distribution of the bistable holding magnetic circuit, and the change process of the main magnetic circuit magnetic reluctance during the opening and closing operation. There is a clear coupling relationship between them, so joint optimization is required, rather than adjusting a single parameter in isolation.

[0079] Let the vector of parameters to be optimized be: ;in, The thickness of the magnetic shielding sheet for the static iron core, The thickness of the magnetic shielding sheet of the moving iron core. The effective length of the magnetic shielding sheet in the stationary iron core. The effective length of the magnetic shielding sheet of the moving iron core. The volume ratio of the upper and lower sections of the permanent magnet on each side. For the working air gap of the tripping switch, This is the working air gap for closing. The working air gap includes the working air gap for opening and the working air gap for closing.

[0080] For any set of parameters A finite element model of the corresponding operating mechanism is established, and the magnetic field distribution in the open holding state, the closed holding state, the initial open state, and the initial closed state is solved respectively, thereby obtaining the open holding force. Closing holding force Coupling coefficient and magnetic flux utilization The coupling coefficient and flux utilization rate are defined as follows:

[0081] ;

[0082] In the formula, The total magnetic flux of the coil excitation. For the coupling magnetic flux to enter the working magnetic circuit on the other side, The effective magnetic flux to enter the target working magnetic circuit. Reflects the degree of ineffective linkage between the opening and closing coils. These two parameters reflect the degree to which the coil excitation flux is utilized for effective driving; therefore, they can be used as evaluation indicators for coupling suppression capability and dynamic magnetic circuit quality, respectively. Clearly, during parameter design, these two parameters should be considered... Minimize as much as possible, Make it as large as possible.

[0083] To ensure that the bistable permanent magnet operating mechanism has sufficient permanent magnet holding capability in both the open and closed holding states, the opening holding force and the closing holding force are constrained as follows:

[0084] ;

[0085] in, and These represent the minimum holding forces required for opening and closing hold, respectively. To balance coupling suppression, flux utilization, and bistable holding capability, a comprehensive objective function is constructed:

[0086] ;

[0087] in, Combination of variables to be optimized The objective function; For the tripping holding force; For closing holding force; The coupling coefficient; For magnetic flux utilization; The minimum holding force required to maintain the tripped circuit breaker; The minimum holding force required to maintain the circuit breaker position during closing; , , These are the weighting coefficients, and .

[0088] By analyzing the objective function Minimization can achieve a balance between reducing coil coupling, improving flux utilization, and maintaining bistable operation.

[0089] In the particle swarm optimization process, each particle is associated with a set of parameters to be optimized. Its flight speed is recorded as . No. During the nth iteration, the 1st The formulas for updating the velocity and position of each particle are as follows:

[0090] ;

[0091] ;

[0092] in, This represents the update adjustment amount for the i-th initial parameter combination in the (r+1)-th iteration; For inertial weights, For individual learning factors; For group learning factors; and All are intervals Random numbers within; For the first The initial parameter combination in the th... The optimal combination of parameters for each individual in the next iteration. The optimal combination of parameters globally; This represents the update adjustment amount for the i-th initial parameter combination in the r-th iteration; For the first The initial parameter combination in the th... The updated initial parameter combination obtained in the next iteration.

[0093] During the optimization process of the particle swarm optimization algorithm For the first The particle in the first The optimal position of an individual in the next iteration. This represents the global optimal position for the current group.

[0094] After each parameter update, the corresponding finite element model is rebuilt and the objective function value is calculated. This completes the iterative search of the parameter space.

[0095] Furthermore, boundary constraints are set for each parameter during the optimization process:

[0096] ;

[0097] in, and These represent the lower and upper limits of the design for each parameter to be optimized.

[0098] When the following conditions are met: Or the number of iterations has reached the preset limit. When the time is right, terminate the optimization iteration and combine the obtained globally optimal parameters. As the final design result.

[0099] The function value for the (r+1)th iteration. Let r be the function value of the r-th iteration. This is a preset threshold for the difference between function values.

[0100] Through the aforementioned collaborative optimization process based on particle swarm optimization, a matching relationship can be established between the parameters of the magnetic shielding sheets of the moving and stationary iron cores, the proportional parameters of the upper and lower segmented permanent magnets, and the air gap parameters for opening and closing. This enables the mechanism to have stable permanent magnet holding capability in both the opening and closing holding states. Simultaneously, during the opening and closing operations, the coil excitation flux preferentially closes along the central stationary iron core and the upper and lower segmented permanent magnet regions, thereby reducing the coupling degree between the opening and closing coils, improving the coil flux utilization rate, reducing magnetic circuit losses, and improving the overall action performance and control stability of the operating mechanism.

Claims

1. A bistable permanent magnet operating mechanism, characterized in that, The bistable permanent magnet operating mechanism includes: a moving iron core, a moving iron core magnetic shielding sheet disposed on the outer periphery of the moving iron core, a stationary iron core sleeved on the outside of the moving iron core, and a first electromagnetic component, a stationary iron core magnetic shielding sheet, and a second electromagnetic component embedded in the internal cavity of the stationary iron core and arranged along the axial direction of the moving iron core. The first electromagnetic component and the second electromagnetic component are arranged around the outer periphery of the moving iron core and respectively disposed on both sides of the magnetic shielding sheet of the stationary iron core; the first electromagnetic component includes a first permanent magnet and a closing coil arranged on the axial outer side of the first permanent magnet; the second electromagnetic component includes a second permanent magnet and a opening coil arranged on the axial outer side of the second permanent magnet. Among them, the parameters of the static iron core magnetic shielding sheet, the parameters of the moving iron core magnetic shielding sheet, the volume ratio of the first permanent magnet and the second permanent magnet, and the working air gap are used as the combination of variables to be optimized. By constructing an objective function that characterizes the coupling degree, magnetic flux utilization rate and steady-state maintenance capability, the value of the combination of variables to be optimized is determined.

2. The bistable permanent magnet operating mechanism according to claim 1, characterized in that, The first permanent magnet includes a first left permanent magnet and a first right permanent magnet; the second permanent magnet includes a second left permanent magnet and a second right permanent magnet. The end face of the first left permanent magnet is opposite to the end face of the first right permanent magnet; The end face of the second left permanent magnet is opposite to the end face of the second right permanent magnet.

3. A method for collaborative optimization of key magnetic circuit parameters of a bistable permanent magnet operating mechanism, characterized in that, The method, applied to the bistable permanent magnet operating mechanism according to any one of claims 1-2, comprises: Using the parameters of the stationary iron core magnetic shielding sheet, the parameters of the moving iron core magnetic shielding sheet, the volume ratio of the first permanent magnet and the second permanent magnet, and the working air gap as the combination of variables to be optimized, the opening holding force, closing holding force, coupling coefficient, and magnetic flux utilization rate of the bistable permanent magnet operating mechanism corresponding to the combination of variables to be optimized are determined. Based on the opening holding force, closing holding force, coupling coefficient, and flux utilization, an objective function is constructed to characterize the degree of coupling, flux utilization, and steady-state holding capability. Based on the objective function, the optimal solution of the combination of variables to be optimized is determined to obtain the key magnetic circuit parameters of the bistable permanent magnet operating mechanism.

4. The method for collaborative optimization of key magnetic circuit parameters of the bistable permanent magnet operating mechanism according to claim 3, characterized in that, The objective function is: ； in, Combination of variables to be optimized The objective function; For the tripping holding force; For closing holding force; The coupling coefficient; For magnetic flux utilization; The minimum holding force required to maintain the tripped circuit breaker; The minimum holding force required to maintain the circuit breaker position during closing; , , These are the weighting coefficients.

5. The method for collaborative optimization of key magnetic circuit parameters of the bistable permanent magnet operating mechanism according to claim 3, characterized in that, Based on the objective function, determine the optimal solution for the combination of variables to be optimized, including: Based on the boundaries of each parameter in the combination of variables to be optimized, generate multiple initial parameter combinations; Based on the function value of the objective function corresponding to each initial parameter combination, determine the individual optimal parameter combination and the global optimal parameter combination; The initial parameter combinations are updated based on the individual optimal parameter combination, the global optimal parameter combination, the inertia weight, the individual learning factor, and the group learning factor. The updated initial parameter combination is used as the initial parameter combination. The operation of determining the individual optimal parameter combination and the global optimal parameter combination, as well as the operation of updating multiple initial parameter combinations, are repeatedly executed until the preset iteration condition is met. Based on the globally optimal parameter combination obtained when the preset iteration conditions are met, the key magnetic circuit parameters of the bistable permanent magnet operating mechanism are determined.

6. The method for collaborative optimization of key magnetic circuit parameters of the bistable permanent magnet operating mechanism according to claim 5, characterized in that, In the initial execution, when determining the individual optimal parameter combination and the global optimal parameter combination, the individual optimal parameter combination and the global optimal parameter combination are determined based on the function value of the objective function corresponding to each initial parameter combination, including: Each of the initial parameter combinations is taken as its own individual optimal parameter combination, and the individual optimal parameter combination with the smallest function value is determined from the multiple individual optimal parameter combinations as the global optimal parameter combination.

7. The method for collaborative optimization of key magnetic circuit parameters of a bistable permanent magnet operating mechanism according to claim 6, characterized in that, In the process of repeatedly determining the individual optimal parameter combination and the global optimal parameter combination, the individual optimal parameter combination and the global optimal parameter combination are determined based on the function value of the objective function corresponding to each initial parameter combination, including: For any given initial parameter combination, if the function value corresponding to the initial parameter combination at the current iteration number is less than the function value corresponding to the individual optimal parameter combination, then the initial parameter combination at the current iteration number shall be taken as the individual optimal parameter combination. Compare the function values ​​corresponding to the multiple individual optimal parameter combinations at the current iteration number with the function values ​​corresponding to the global optimal parameter combination at the current iteration number; If the comparison result indicates that the function value corresponding to the individual optimal parameter combination at the current iteration number is less than the function value corresponding to the global optimal parameter combination at the current iteration number, the individual optimal parameter combination at the current iteration number is taken as the global optimal parameter combination to update the global optimal parameter combination at the current iteration number.

8. The method for collaborative optimization of key magnetic circuit parameters of a bistable permanent magnet operating mechanism according to claim 5, characterized in that, The initial parameter combinations are updated based on the individual optimal parameter combination, the global optimal parameter combination, the inertia weight, the individual learning factor, and the group learning factor, including: Based on the individual optimal parameter combination, the global optimal parameter combination, the inertia weight, the individual learning factor, and the group learning factor, determine the update adjustment amount for each of the initial parameter combinations; The initial parameter combinations are updated based on the update adjustment amount.

9. The method for collaborative optimization of key magnetic circuit parameters of a bistable permanent magnet operating mechanism according to claim 8, characterized in that, The formula for determining the update adjustment amount for each of the initial parameter combinations is: ； in, This represents the update adjustment amount for the i-th initial parameter combination in the (r+1)-th iteration; For inertial weights, For individual learning factors; For group learning factors; and All are intervals Random numbers within; For the first The initial parameter combination in the th... The optimal combination of parameters for an individual under the number of iterations. The globally optimal parameter combination for the r-th iteration; This represents the update adjustment amount for the i-th initial parameter combination in the r-th iteration; For the first The initial parameter combination in the th... The updated initial parameter combination obtained in the next iteration.

10. The method for collaborative optimization of key magnetic circuit parameters of a bistable permanent magnet operating mechanism according to claim 4, characterized in that, The formula for the coupling coefficient is: ； The formula for the magnetic flux utilization rate is: ； in, The coupling coefficient; For magnetic flux utilization; The total magnetic flux of the coil excitation. For the coupling magnetic flux to enter the working magnetic circuit on the other side, The effective magnetic flux to enter the target working magnetic circuit.

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