A toroidal magnetic circuit reactor

Abstract

This application provides a toroidal magnetic circuit reactor, relating to the field of electrical equipment technology. The specific solution includes a first magnetic yoke, a second magnetic yoke, a core assembly, and a core coil. The second magnetic yoke is spaced apart from the first magnetic yoke. The core assembly includes at least two cores, each core assembly including at least one core, with any two cores arranged at intervals. One end of each core is connected to the first magnetic yoke, and the other end is connected to the second magnetic yoke to form a magnetic circuit. At least one air gap is provided in the magnetic circuit formed by the first magnetic yoke, the second magnetic yoke, and the core. At least one core coil is included, and the core coil is wound around a core. The toroidal magnetic circuit reactor provided in this application can independently achieve high-performance differential-mode filtering on a single iron core, and can also be upgraded to integrated differential and common-mode filtering. Furthermore, this structure has strong magnetic circuit adaptability, can fully utilize various high-performance soft magnetic materials, and achieves low loss, high balance, and easy serialization production.

Description

Technical Field

[0001] This application relates to the technical field of electrical equipment, and specifically relates to an annular magnetic circuit reactor. Background Art

[0002] In the field of power electronics such as drive speed control systems and tuned inductors, the currently commonly used reactors mainly have the following two structures:

[0003] 1. "Day" character planar structure reactor

[0004] This structure uses a "day" character planar iron core, which has three coil columns (such as the middle column and the two side columns), and the three-phase coils are respectively wound on the three columns. The iron core and the coils are arranged in a plane. Its function is mainly positioned for differential mode filtering, and can be used to suppress power frequency harmonic components, improve power factor, and absorb surge current. In three-phase applications, this structure realizes three-phase filtering through three planar magnetic paths, and the coil lead-out method is usually lead-out from both sides or one side.

[0005] 2. Laminated three-dimensional structure reactor

[0006] This structure uses non-oriented silicon steel sheets stacked to form a three-dimensional symmetric magnetic circuit. The overall iron core has a three-dimensional symmetric shape, and the magnetic path lengths of each phase are equal, and the inductance is balanced. This structure also mainly functions as differential mode filtering and is suitable for occasions with high requirements for current balance and control accuracy. Its manufacturing process usually adopts the punching and laminating process, and the iron core window and the coil installation position are fixed.

[0007] In the above two structures, the installation position of the coil is restricted within the pre-set iron core column or window area, and the coils are connected in a fixed manner, and the layout and combination of the coils in the magnetic circuit cannot be flexibly adjusted according to functional requirements.

[0008] However, the above-mentioned existing technologies have the following defects and deficiencies in application:

[0009] 1. Single function and high system integration cost

[0010] Both of the existing reactors do not have the ability of common mode filtering and can only achieve differential mode filtering. In an actual system, if it is necessary to suppress common mode interference, an additional independent common mode filter must be connected in series. This results in: an increase in the number of components; an increase in the system installation space; a significant increase in the material cost and the system integration cost.

[0011] 2. The "day" character planar structure has magnetic circuit asymmetry and inductance imbalance, which affect the control accuracy

[0012] 2.1 Unequal three-phase magnetic circuit lengths: Due to the difference in position of the three coil posts in the planar layout (the magnetic circuit path lengths of the two side posts and the middle post are different), the inductance of each phase can deviate by 5% to 10%, causing three-phase current imbalance and affecting the control accuracy and stability of the speed regulation system.

[0013] 2.2. Ineffective Half-Turn Problem: When using a two-sided lead-out configuration, an ineffective half-turn will form in one phase (usually the winding corresponding to the side column). This part of the current cannot be effectively coupled to the iron core, further aggravating the inductance deviation, while also increasing copper losses and reducing efficiency. This problem is relatively milder when using a one-sided lead-out configuration, but it still cannot completely avoid the inductance deviation caused by magnetic circuit asymmetry.

[0014] 3. The stacked three-dimensional structure of the laminations suffers high losses, failing to leverage the energy-saving advantages of oriented high-performance materials.

[0015] These products generally use non-oriented silicon steel sheets, resulting in high core unit losses (iron losses), making it difficult to further reduce reactor body losses and leading to low system efficiency. Even if oriented silicon steel sheets with lower losses are used, the magnetic flux direction in the three-dimensional symmetrical magnetic circuit cannot be kept consistent with the rolling direction of the silicon steel sheet on all paths. Most of the magnetic flux will deviate from the rolling direction, making it impossible to utilize the low-loss characteristics of oriented materials, resulting in poor energy-saving effect and low material utilization.

[0016] 4. The fixed magnetic circuit position of the coil installation results in limited product variety and difficulty in serialization.

[0017] 4.1. Limited Functionality: It is impossible to achieve common-mode filtering, differential-mode / common-mode integration, or other composite functions by installing different coils at different locations in the magnetic circuit (such as different magnetic pillars, magnetic circuit branches, air gap bypasses, etc.) and combining them in series, parallel, or by magnetic flux superposition / cancellation. The existing structure can only manufacture one type of product: differential-mode filter reactors.

[0018] 4.2 Limited Derivative Varieties: To produce common-mode reactors, composite reactors, or special reactors with different harmonic suppression levels, the core mold and magnetic circuit topology must be redesigned. It's impossible to quickly derive products using standardized cores and different coil layouts. This results in a narrow product line, long design cycles, high mold costs, and difficulty in achieving serialized production and flexible manufacturing.

[0019] 5. Poor economic efficiency under high current and high inductance conditions.

[0020] For stacked lamination structures, when large currents or high inductance are required, the fixed magnetic circuit position of the coil prevents optimization of magnetic flux distribution and heat dissipation by splitting the coil and arranging it in different magnetic circuit positions. The only solution is to enlarge the overall core and coil dimensions. This leads to:

[0021] 5.1. Internal heat is difficult to dissipate, heat dissipation performance deteriorates, and temperature rises;

[0022] 5.2. The core window filling coefficient is limited, and a large amount of silicon steel sheets and copper wires are not effectively utilized, resulting in low material utilization.

[0023] 5.3. The manufacturing cost per unit of inductance has increased significantly, making it less economical in high-current, high-inductance scenarios. Summary of the Invention

[0024] This application provides a toroidal magnetic circuit reactor that can independently achieve high-performance differential-mode filtering on a single iron core, and can also be upgraded to an integrated differential and common-mode filter. Furthermore, this structure has strong magnetic circuit adaptability, can fully utilize various high-performance soft magnetic materials, and achieves low loss, high balance, and easy mass production.

[0025] The specific technical solution of this embodiment is as follows:

[0026] This application provides a toroidal magnetic circuit reactor, including a first yoke, a second yoke, core groups, and core coils. The second yoke is spaced apart from the first yoke. The core groups include at least two cores, each group including at least one core, with any two cores arranged at intervals. One end of each core is connected to the first yoke, and the other end is connected to the second yoke to form a magnetic circuit. At least one air gap is provided in the magnetic circuit formed by the first yoke, the second yoke, and the cores. At least one core coil is included, and the core coil is wound around a core.

[0027] In some embodiments, the toroidal magnetic circuit reactor further includes a yoke coil, which includes at least one yoke coil; the yoke coil is arranged on a first yoke and / or a second yoke; when the yoke coil is arranged on the first yoke and the second yoke, the yoke coil is two independent coils respectively disposed on the two yokes, or a common coil passing through the first yoke and the second yoke simultaneously; the yoke coil is electromagnetically coupled to the yoke by a conductor passing through the corresponding yoke window and forming at least one turn of electromagnetic coupling with the yoke, and the yoke coil is connected to the core coil on the corresponding toroidal magnetic circuit reactor.

[0028] In some embodiments, in each phase, when there are multiple core coils, the multiple core coils are respectively arranged on each core of the phase, and the multiple core coils are connected in series, parallel or mixed manner; when there are multiple magnetic yoke coils in the phase, the multiple magnetic yoke coils are connected in series, parallel or mixed manner; the whole formed by the connection of the magnetic yoke coils of the phase is connected in series with the whole formed by the connection of the core coils of the phase to form a single-phase coil combination; when there are multiple single-phase coil combinations, the multiple single-phase coil combinations belonging to the same phase are connected in parallel.

[0029] In some embodiments, the first yoke, the second yoke, and the core are each made of one or more soft magnetic materials.

[0030] In some embodiments, the first yoke, the second yoke, and the core post are made of one or more of the following materials: oriented silicon steel, non-oriented silicon steel, amorphous alloy, nanocrystalline alloy, nickel-zinc ferrite, and manganese-zinc ferrite.

[0031] In some embodiments, the first magnetic yoke is a one-piece or multi-segmented ring structure; and / or, the second magnetic yoke is a one-piece or multi-segmented ring structure.

[0032] In some embodiments, the first and / or second magnetic yokes are provided with positioning grooves, and the end of the core post is inserted into the positioning groove; or,

[0033] The first and / or second magnetic yokes are provided with positioning planes, and the ends of the core posts abut against the positioning planes; or,

[0034] The first and / or second magnetic yokes are integrally formed with protrusions that constitute at least a portion of the core post.

[0035] In some embodiments, there are three core pillar groups, each core pillar group including one core pillar, and the three core pillars are evenly arranged at equal angles along a circular path.

[0036] In some embodiments, the toroidal reactor has one or more air gaps in its magnetic circuit.

[0037] In some embodiments, the toroidal magnetic circuit reactor also includes a non-magnetic insulating material or a weakly magnetic material, which is filled into the corresponding positions to form an air gap.

[0038] Compared with the prior art, the embodiments of this application have the following beneficial effects:

[0039] The toroidal magnetic circuit reactor provided in this application embodiment can achieve different filtering functions on the same iron core structure by adjusting the connection method of the core column coil: when only differential mode filtering is required, the core column coil is wound and connected in the conventional way to obtain a three-phase balanced differential mode inductance; when common mode filtering is required at the same time, the core column coil and the yoke coil are connected in series. Under differential mode operation, the magnetic flux enters the upper toroidal yoke through one phase core column, is shunted to the other phase core columns, and returns through the lower toroidal yoke, completely closing through the air gap within the iron core. The differential mode inductance is mainly determined by the core column coil and the air gap reluctance; under common mode operation, the zero-sequence magnetic flux in the core column cannot close along the axial direction and is forced to pass through the air gap to form leakage flux, but the tangential magnetic flux generated by the yoke coil circulates along the air gap-free toroidal yoke, exhibiting a large zero-sequence inductance, which dominates the total zero-sequence impedance, thereby effectively suppressing the common mode current. In this way, a single iron core can simultaneously perform differential mode current limiting and common mode choke, eliminating the need for an additional independent common mode filter, reducing the number of components, and lowering integration costs and installation space requirements. Attached Figure Description

[0040] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0041] Figure 1 This is a schematic diagram of the structure of a toroidal magnetic circuit reactor provided in some embodiments of this application;

[0042] Figure 2 yes Figure 1 Top view;

[0043] Figure 3 This is a three-dimensional schematic diagram of a differential and common-mode integrated reactor provided in some embodiments of this application;

[0044] Figure 4 yes Figure 3 Electrical wiring diagram;

[0045] Figure 5 This is a partial schematic diagram of a high-current multi-core parallel structure provided in some embodiments of this application;

[0046] Figures 6-8 This is a schematic diagram of the magnetic flux path, in which, Figure 6 The path of differential mode flux through the air gap inside the iron core is shown under three-phase symmetrical current. Figure 7 Under common-mode current, the zero-sequence magnetic flux of the core column is squeezed out of the air gap and becomes leakage flux. Figure 8 The diagram illustrates the smooth closed path of the zero-sequence magnetic flux generated by the yoke coil in a gapless annular yoke under common-mode current.

[0047] Figure 9 This is a schematic diagram of a core post with an air gap provided in some embodiments of this application;

[0048] Figure 10 This is a schematic diagram of a structure provided in some embodiments of this application, in which the air gap is set at the segmented joint of the annular magnetic yoke.

[0049] in:

[0050] 1. First yoke; 2. Second yoke; 3. Core column; 3a. Upper sub-core segment; 3b. Lower sub-core segment; 3A. First sub-core column; 3B. Second sub-core column; 4. Air gap; 5. Core column coil; 5A. Phase A core column coil; 6. Magnetic yoke coil; 6A. Phase A upper magnetic yoke coil; 6B. Phase A lower magnetic yoke coil. Detailed Implementation

[0051] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0052] In the description of this application, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating orientation or positional relationships based on the orientation or positional relationships shown in the accompanying drawings, are used only for the convenience of describing this application 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 this application. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, features defined with "first" and "second" may explicitly or implicitly include one or more of the stated features. In the description of this application, "a plurality of" means two or more, unless otherwise explicitly specified.

[0053] The use of "applies to" or "configured to" in this application implies open and inclusive language, which does not exclude the applicability to or configuration to devices performing additional tasks or steps. Additionally, the use of "based on" implies openness and inclusivity, because processes, steps, calculations, or other actions "based on" one or more of the stated conditions or values ​​may in practice be based on additional conditions or values ​​beyond those stated.

[0054] In this application, the term "exemplary" is used to mean "used as an example, illustration, or description." Any embodiment described as "exemplary" in this application is not necessarily to be construed as being more preferred or advantageous than other embodiments. The following description is provided to enable any person skilled in the art to make and use this application. Details are set forth in the following description for purposes of explanation. It should be understood that those skilled in the art will recognize that this application can be made without using these specific details. In other instances, well-known structures and processes are not described in detail to avoid obscuring the description of this application with unnecessary detail. Therefore, this application is not intended to be limited to the embodiments shown, but is consistent with the broadest scope of the principles and features disclosed in this application.

[0055] On one hand, this application provides a toroidal magnetic circuit reactor, including a first yoke 1, a second yoke 2, core groups, and core coils 5. The second yoke 2 is spaced apart from the first yoke 1. The core groups include at least two cores, each core group including at least one core 3, with any two cores 3 arranged at intervals. One end of the core 3 is connected to the first yoke 1, and the other end is connected to the second yoke 2 to form a magnetic circuit. At least one air gap 4 is provided in the magnetic circuit formed by the first yoke 1, the second yoke 2, and the cores 3. The core coils 5 are wound on the cores 3, and at least one core coil 5 is wound on each core 3.

[0056] The first magnetic yoke 1 can be a ring-shaped yoke, or it can be an E-shaped, C-shaped, or rectangular stacked yoke. When the first magnetic yoke 1 is a ring-shaped yoke, it can be a circular ring, an elliptical ring, a polygonal ring, or an irregular closed ring. Similarly, the second magnetic yoke 2 can be a ring-shaped yoke, or it can be an E-shaped, C-shaped, or rectangular stacked yoke. When the second magnetic yoke 2 is a ring-shaped yoke, it can be a circular ring, an elliptical ring, a polygonal ring, or an irregular closed ring. The first magnetic yoke 1 can be integrally formed or it can be composed of multiple segments; similarly, the second magnetic yoke 2 can be integrally formed or it can be composed of multiple segments. The first magnetic yoke 1 and the second magnetic yoke 2 can have the same shape or they can have different shapes.

[0057] The number of core column groups varies depending on whether the reactor is a single-phase or three-phase reactor. When the reactor is a single-phase reactor, the core column group consists of two core columns; when the reactor is a three-phase reactor, the core column group consists of three core columns. Each core column group includes at least one core column 3; a core column group can consist of one core column 3, or it can consist of two or more core columns 3. In this embodiment, the reactor includes at least two core columns 3.

[0058] The air gap 4 can be located on the first magnetic yoke 1, the second magnetic yoke 2, or the core post 3. The air gap 4 can exist only between the core post 3 and the first magnetic yoke 1, only between the core post 3 and the second magnetic yoke 2, or between both the core post 3 and the first and second magnetic yokes 2. The air gap 4 can be formed using a non-magnetic insulating material, such as epoxy board or insulating paper; or it can be formed by an air gap.

[0059] It can be that one core post 3 is wound with one core post coil 5, or it can be that one core post 3 is wound with two or more core post coils 5.

[0060] Through the above embodiments, the toroidal magnetic circuit reactor can achieve different filtering functions on the same iron core structure by adjusting the winding direction and series-parallel connection method of the core coil 5: when only differential-mode filtering is required, the core coil 5 can be wound and connected in the conventional way to obtain a three-phase balanced differential-mode inductance; when common-mode filtering is required at the same time, the core coil 5 is connected in series with the yoke coil 6 arranged on the yoke. Under differential-mode conditions, the magnetic flux is completely closed within the iron core through the air gap 4, and the differential-mode inductance is mainly determined by the magnetic reluctance of the core coil 5 and the air gap 4 in the core 3; under common-mode conditions, the tangential magnetic flux generated by the yoke coil 6 circulates along the toroidal yoke (first yoke 1 and second yoke 2) without the air gap 4, exhibiting a maximum zero-sequence inductance, which dominates the single-phase total impedance, thereby effectively suppressing the common-mode current. In this way, a single iron core can simultaneously complete differential-mode current limiting and common-mode current choking without the need for an additional independent common-mode filter, reducing the number of system components and lowering integration costs and installation space occupation.

[0061] In some embodiments, the toroidal magnetic circuit reactor further includes a yoke coil 6, which comprises at least one coil arranged on a first yoke 1 and / or a second yoke 2. When the yoke coil 6 is arranged on the first yoke 1 and the second yoke 2, the yoke coil 6 is either two independent coils respectively disposed on the two yokes, or a common coil passing through both the first yoke 1 and the second yoke 2 simultaneously; the yoke coil 6 is electromagnetically coupled with the corresponding yoke window by a conductor, forming at least one turn of electromagnetic coupling with the yoke, and the yoke coil 6 is connected to the core coil 5 on the corresponding toroidal magnetic circuit reactor.

[0062] The magnetic yoke coil 6 may include one, two, or even more. It may be that only the first magnetic yoke 1 has the magnetic yoke coil 6 wound on it, only the second magnetic yoke 2 has the magnetic yoke coil 6 wound on it, or both the first magnetic yoke 1 and the second magnetic yoke 2 may have the magnetic yoke coil 6 wound on it. When the first magnetic yoke 1 has the magnetic yoke coil 6 wound on it, the magnetic yoke coil 6 may be provided on at least one segment of the magnetic circuit of the first magnetic yoke 1; or the magnetic yoke coil 6 may be provided on some segments of the magnetic circuit of the first magnetic yoke 1; similarly, when the second magnetic yoke 2 has the magnetic yoke coil 6 wound on it, the magnetic yoke coil 6 may be provided on at least one segment of the magnetic circuit of the second magnetic yoke 2; or the magnetic yoke coil 6 may be provided on some segments of the magnetic circuit of the second magnetic yoke 2; or the magnetic yoke coil 6 may be provided on all segments of the magnetic circuit of the second magnetic yoke 2.

[0063] Through the above embodiments, the configuration of the yoke coil 6 enables independent coupling of the common-mode magnetic flux, allowing for more flexible adjustment of the common-mode inductor parameters. This eliminates the need to alter the original winding layout of the core coil 5; simply by increasing or decreasing the number of turns of the yoke coil 6 and adjusting its connection method, different levels of common-mode filtering requirements can be met. Furthermore, the cooperation between the yoke coil 6 and the core coil 5 allows for the rapid generation of products with different functions and parameter specifications by adjusting the coil layout while maintaining the overall topology of the toroidal magnetic circuit. This eliminates the need to redesign the core mold, significantly reducing the development cycle and mold costs for serialized products and facilitating flexible production.

[0064] In some embodiments, in each phase, when there are multiple core column 3 coils, the multiple core column 3 coils are respectively arranged on each core column 3 of the phase, and the multiple core column 3 coils are connected in series, parallel or mixed manner; when there are multiple magnetic yoke coils 6 of the phase, the multiple magnetic yoke coils 6 are connected in series, parallel or mixed manner; the whole formed by the connection of the magnetic yoke coils 6 of the phase is connected in series with the whole formed by the connection of the core column 3 coils of the phase to form a single-phase coil combination; when there are multiple single-phase coil combinations, the multiple single-phase coil combinations belonging to the same phase are connected in parallel.

[0065] Through the above embodiments, the coil layout of the same phase can be flexibly adjusted according to actual filtering requirements. While keeping the toroidal magnetic circuit core structure unchanged, the corresponding differential mode and common mode inductance parameters can be obtained through different connection methods, further improving the flexibility of product derivation and adjustment, and adapting to different harmonic suppression requirements.

[0066] In some embodiments, the first yoke 1, the second yoke 2, and the core 3 are each made of one or more soft magnetic materials.

[0067] The above embodiments allow for flexible material matching based on different working conditions.

[0068] In some embodiments, the first magnetic yoke 1, the second magnetic yoke 2, and the core post 3 are each made of one or more soft magnetic materials selected from the following materials: industrial pure iron, electrical steel (silicon steel), iron-nickel based permalloy, iron-cobalt based permalloy, iron-aluminum alloy, iron-silicon-aluminum, manganese-zinc or nickel-zinc soft magnetic ferrite, iron-based amorphous alloy (including iron-silicon-boron system), cobalt-based amorphous alloy, iron-based nanocrystalline alloy, and soft magnetic composite powder material (SMC).

[0069] The first magnetic yoke 1 can be made of one of the materials mentioned above; or it can be made of multiple materials mentioned above, for example, when the first magnetic yoke 1 is composed of multiple segments, multiple materials can be used. Similarly, the second magnetic yoke 2 can be made of one of the materials mentioned above; or it can be made of multiple materials mentioned above, for example, when the first magnetic yoke 1 is composed of multiple segments, multiple materials can be used. The core column 3 can be made of one of the materials mentioned above; or it can be made of multiple materials mentioned above, for example, when the first magnetic yoke 1 is composed of multiple segments, multiple materials can be used; different core columns 3 can use the same material, or different core columns 3 can use different materials. The first magnetic yoke 1, the second magnetic yoke 2, and the core column 3 can all use the same material, two of them can use the same material, or all three can use different materials.

[0070] Through the settings of the above embodiments, soft magnetic materials with different properties can be matched according to the magnetic flux direction of the magnetic circuit.

[0071] For example, the first yoke 1 and the second yoke 2 can be wound with amorphous alloy strips to achieve extremely low losses, while the core 3 is made of oriented silicon steel sheets to balance cost and saturation characteristics; or the first yoke 1 and the second yoke 2 can be made of ferrite, and the core 3 can be made of nanocrystalline alloy to adapt to high-frequency operating conditions. When oriented silicon steel strips or amorphous / nanocrystalline strips are used for winding, the circumferential direction of the first yoke 1 and the second yoke 2 is the preferred magnetization direction of the material.

[0072] In other embodiments, the first yoke 1, the second yoke 2, and the core post 3 may each be made of any other soft magnetic material suitable for the operating frequency.

[0073] In some embodiments, the first magnetic yoke and / or the second magnetic yoke are provided with positioning grooves, and the end of the core post is inserted into the positioning groove.

[0074] Through the above-described embodiments, the cooperation between the positioning protrusion and the positioning groove can improve assembly accuracy and mechanical stability, reduce magnetic resistance fluctuations at the contact surface, and facilitate the disassembly and replacement of the core post 3. The shape of the first positioning groove can be a rectangular groove, a trapezoidal groove, a dovetail groove, etc., and similarly, the shape of the second positioning groove can also be a rectangular groove, a trapezoidal groove, a dovetail groove, etc.

[0075] In other embodiments, the first and / or second magnetic yokes are provided with positioning planes, and the ends of the core posts abut against the positioning planes.

[0076] With the above embodiments, the process of machining the positioning plane is simple, making it easy to control machining accuracy, reducing the machining cost of core components, and improving the consistency of magnetic circuit dimensions after assembly. Under high current and high inductance conditions, the heat generated by the coil can be directly conducted to the outer first and second magnetic yokes through the core column. The contact area between the magnetic yokes and the outside air is larger, which can quickly dissipate the heat into the environment. Compared with the traditional lamination stack structure where heat accumulates inside and is difficult to dissipate, this effectively reduces the overall temperature rise of the reactor, improves the heat dissipation conditions under high current conditions, and enhances the stability and service life of the product.

[0077] In some other embodiments, the first yoke and / or the second yoke are integrally formed with protrusions that form at least a portion of the core post.

[0078] The above-described embodiments eliminate the need for separate machining and assembly processes for the core column and yoke, reducing assembly errors and lowering contact magnetic resistance, thus improving the overall magnetic performance of the magnetic circuit. Furthermore, the one-piece molded structure offers higher mechanical strength, better withstanding the electromagnetic forces from high currents, preventing structural loosening from affecting inductance parameter stability, and further reducing the risk of structural failure under high-current conditions.

[0079] In some embodiments, there are three core pillar groups, each core pillar group including one core pillar 3, and the three core pillar groups are evenly arranged at equal angles along a circular path.

[0080] Through the configuration of the above embodiments, the three core columns have symmetrical magnetic circuits, resulting in good consistency of three-phase inductance. This adapts to the operating conditions of three-phase three-wire and three-phase four-wire power electronic systems, effectively improving the control accuracy of the three-phase output and reducing the impact of magnetic circuit asymmetry on control stability. Simultaneously, the uniformly arranged structure also makes the overall magnetic field distribution of the reactor more uniform, reducing leakage flux and further minimizing additional losses.

[0081] In some other embodiments, there are three core pillar groups, each core pillar group including one core pillar 3, and the three core pillars 3 are arranged at unequal intervals along a circular path.

[0082] In some embodiments, the toroidal reactor has one or more air gaps 4 on its magnetic circuit.

[0083] By adjusting the number, position and total length of the air gaps 4 as described in the above embodiments, the size of the differential mode inductor can be easily controlled to match different current limiting requirements. At the same time, the presence of the air gaps 4 can also delay core saturation and improve the stability of the reactor under high current conditions.

[0084] In some embodiments, the toroidal magnetic circuit reactor further includes a non-magnetic insulating pad, which fills or weakly conducts magnetic material to form an air gap 4 at the corresponding position.

[0085] Through the above embodiment, the non-magnetic insulating pad can stabilize the gap 4, reduce the deformation of the gap 4 under external pressure, improve the long-term stability of the inductance parameters, and also play an insulating role, reducing the eddy current loss generated by direct contact between the two ends of the core post 3 and the magnetic yoke.

[0086] In some embodiments, each core post group includes at least two core posts 3, the core posts 3 of each core post group are connected in parallel, and each core post 3 is wound with a core post coil 5. The core post coils 5 wound on all the core posts 3 of each core post group are connected in parallel or in series.

[0087] By configuring a core post group as several core posts 3 connected in parallel through the above embodiments, the heat dissipation area can be further increased, the magnetic flux can be homogenized, and local hot spots can be reduced.

[0088] The toroidal magnetic circuit reactor provided in this application embodiment can realize a pure differential mode reactor or a differential-common mode integrated reactor through different coil configurations.

[0089] (1) Implementation plan for pure differential mode reactor

[0090] The core coil 5 is wound only on each core 3. Each phase winding consists of one or more core coils 5.

[0091] When the core column 3 is a whole, the core column coil 5 of that phase is directly wound on the core column 3.

[0092] When a single-phase core column 3 is composed of multiple (e.g., two or three) smaller core columns (i.e., each core column group includes multiple core columns 3 connected in parallel), a core column coil 5 is wound on each smaller core column 3. These core column coils 5 are then connected in parallel or in series to form the winding for that phase. Splitting a large core column 3 into several smaller core columns 3 connected in parallel can further increase the heat dissipation area, homogenize the magnetic flux, and reduce local hot spots.

[0093] (2) Implementation plan for differential and common mode integrated reactor

[0094] Based on the pure differential mode reactor structure, a yoke coil 6 is further wound on the annular yoke (i.e., the collective term for the first yoke 1 and the second yoke 2, including at least one of the first yoke 1 and the second yoke 2). The arrangement of the yoke coil 6 is flexible and can be selected in any of the following combinations according to common mode suppression requirements, manufacturing costs, and assembly convenience:

[0095] Method A: Top winding only. The yoke coil 6 is wound only on each segment of the magnetic circuit of the first yoke 1, and the yoke coil 6 is not wound on the second yoke 2.

[0096] Method B: Lower winding only. The yoke coil 6 is wound only on each segment of the magnetic circuit of the second yoke 2, and the yoke coil 6 is not wound on the first yoke 1.

[0097] Method C: Winding both top and bottom. Magnetic yoke coils 6 are wound on each segment of the magnetic circuit of the first magnetic yoke 1 and the corresponding segment of the magnetic circuit of the second magnetic yoke 2.

[0098] Method D: The first yoke 1 and the second yoke 2 pass through the yoke coil 6 simultaneously.

[0099] The basic formation method of the yoke coil 6 is as follows: the yoke coil 6 is formed by an insulated wire or flat copper wire passing through the annular yoke window where the corresponding magnetic circuit is located, and forming an electromagnetic coupling with the segment of the yoke by at least one turn. That is, for any of the above methods, the yoke coil 6 on each segment has at least one turn of coupling. When the number of turns is one, the conductor only needs to pass through the annular yoke window once to achieve electromagnetic coupling with the segment of the magnetic circuit; at this time, regardless of whether the conductor wraps around the outer circumference of the yoke cross section, as long as a closed conductive loop is formed and linked with the segment of the magnetic circuit, it is considered that a yoke coil 6 has been formed. Increasing the number of turns can enhance the coupling strength, and can be set as needed. This winding method of "passing through the annular yoke" makes the direction of the magnetomotive force generated by the yoke coil 6 tangential to the circumference of the annular yoke.

[0100] Each phase winding consists of the corresponding phase core coil 5 connected in series with the set magnetic yoke coil 6. For example, when using method C (winding both the top and bottom), the A phase winding is composed of the A phase core coil 5, the A phase upper magnetic yoke coil 6A, and the A phase lower magnetic yoke coil 6B connected in series; when using method A (winding only the top), the A phase winding is composed of the A phase core coil 5A and the A phase upper magnetic yoke coil 6A connected in series.

[0101] The winding direction of each coil is configured as follows: when a three-phase symmetrical current flows through, the axial magnetic flux of the core column 3 and the magnetic flux in the segments of the annular yoke form a closed path inside the iron core; when a common-mode (zero-sequence) current flows through, the tangential magnetomotive force generated by each phase yoke coil 6 in each segment is superimposed in the same direction along the circumference of the annular yoke. The specific winding direction configuration rule is as follows: taking a three-phase system as an example, a certain direction (such as clockwise) along the circumference of the annular yoke is defined as the positive reference direction. The yoke coil 6A on phase A is wound in a way that generates a clockwise tangential magnetomotive force; the yoke coil 6 on phase B is also wound in a way that generates a clockwise tangential magnetomotive force in its segment; the same applies to the yoke coil 6 on phase C. The winding direction of the yoke coil 6 on the second yoke 2 follows the same principle. In this way, when a common-mode current of the same phase flows through the three phases, the tangential magnetomotive force generated by all the yoke coils 6 is superimposed in the same circumferential direction within the annular yoke, forming a closed, efficient zero-sequence magnetic circuit.

[0102] (3) Implementation plan for pure common mode reactor

[0103] It is understandable that, based on the same core platform, it is also possible to wind only the yoke coil 6 without winding the core coil 5, thereby forming a pure common-mode reactor. In this case, each phase winding is composed of the yoke coil 6 wound on the first yoke 1 and / or the second yoke 2 segments, and the winding direction of the three-phase yoke coil 6 is configured to generate tangential magnetomotive forces superimposed in the same direction along the circumference under common-mode current.

[0104] Detailed Explanation of Working Principle

[0105] (1) Three-phase symmetrical current (differential mode) operating condition

[0106] Taking the positive peak value of phase A current as an example, the magnetic flux of phase A core column 3 enters upward into the first magnetic yoke 1, and after being shunt, it enters the upper ends of phase B and C core columns 3 along the segments of the annular magnetic yoke, then flows downward through phase B and C core columns 3 into the second magnetic yoke 2, and finally converges back to the lower end of phase A core column 3 through the segments of the second magnetic yoke 2. The magnetic flux is completely closed within the iron core through the air gap 4. The three-phase magnetic flux is symmetrical, forming a magnetic flux wave within the annular magnetic yoke.

[0107] Under this operating condition, the three-phase currents in the yoke coil 6 (if present) are also symmetrical, and their combined tangential magnetomotive forces weaken each other, having minimal impact on the differential-mode inductance. The differential-mode inductance is mainly determined by the magnetic reluctance of the air gap 4 of the core column 3, exhibiting good linearity. When the core columns 3 are evenly distributed at equal angles on the annular yoke, the magnetic circuit lengths of each phase are completely equal, the three-phase inductances are highly balanced, and the imbalance can be less than 1.5%.

[0108] (2) Common-mode (zero-sequence) current condition

[0109] When a common-mode current of the same phase flows through the three phases, the axial magnetomotive force of the three core columns 3 is in the same direction, simultaneously "pushing" the zero-sequence axial magnetic flux into the annular yoke. Since the three nodes are all "flowing in" (or "flowing out" in the same direction), the core column 3 cannot provide a closed loop for the axial zero-sequence magnetic flux. This flux is forced to pass through the air gap 4 and form a leakage magnetic circuit through the external air (or oil). At this time, the zero-sequence inductance of the core column coil 5 is extremely small.

[0110] However, under common-mode current, the yoke coils 6 on the segments of the annular yoke (regardless of whether they are wound on the top, bottom, or both, and regardless of whether they have one or more turns) have the same current phase, and the resulting tangential magnetomotive forces are aligned in the same direction and superimposed on the circumference of the annular yoke. This tangential magnetic flux can smoothly close along the annular yoke body without air gap 4, resulting in extremely low magnetic reluctance. Therefore, the yoke coils 6 exhibit a very large zero-sequence inductance.

[0111] Each phase winding consists of a core coil 5 connected in series with a yoke coil 6. Therefore, the single-phase zero-sequence impedance is dominated by the large inductance of the yoke coil 6, resulting in a very high common-mode impedance and effectively suppressing common-mode current. This structure achieves both differential-mode current limiting and common-mode choke using only one set of iron cores.

[0112] Manufacturing and serialization methods

[0113] The same basic magnetic circuit platform with a toroidal yoke and core column 3 can be quickly used to generate a variety of products simply by changing the winding position, number of turns, and connection method of the coils.

[0114] Only the core coil 5 → pure differential mode reactor.

[0115] Core coil 5 + yoke coil 6 connected in series (optional: upper winding only, lower winding only, or both windings, yoke coil 6 with ≥1 turn) → differential and common mode integrated reactor.

[0116] Only the magnetic yoke coil 6 (optional: only the upper winding, only the lower winding, or both windings, with ≥1 turn) → pure common-mode reactor.

[0117] Adjust the size, material, and number of turns of the air gap 4 to create reactors with different inductance and frequency characteristics.

[0118] This standardized iron core and flexible assembly model greatly reduces mold investment and design cycle.

[0119] In addition, for high-current applications, each core post 3 can be split into multiple sub-core posts 3 and wound separately and connected in parallel or series. This can distribute the ampere-turns without increasing the cross-section of the single core, optimize heat dissipation and improve material utilization.

[0120] 1. Shape substitution: The first magnetic yoke 1 and the second magnetic yoke 2 can be circular rings, elliptical rings, polygonal rings, or triangular rings. Polygonal rings are not limited to regular polygons, and the lengths of the sides can be unequal, as long as the whole forms a closed loop.

[0121] 2. Alternative arrangement of core column 3: Core columns 3 can be arranged at unequal intervals on the annular yoke. When the requirement for three-phase balance is not high, a non-equidistant arrangement can also work; when a high degree of balance of three-phase inductance is required, an equidistant (e.g., 120°) arrangement is preferred.

[0122] 3. Alternative connection method between the annular magnetic yoke and the core post 3: A slot can be made at the connection point between the annular magnetic yoke and the core post 3, and the end of the core post 3 is embedded in the slot for positioning. This slotted connection method improves assembly accuracy and mechanical stability, reduces magnetic reluctance fluctuations at the contact surface, and facilitates the disassembly and replacement of the core post 3. The slot shape can be rectangular, trapezoidal, dovetail, etc.

[0123] 4. Replacement of the position of air gap 4: Air gap 4 can be set at the end of core column 3, or it can be set entirely or partially at the segment joint of the annular magnetic yoke, or between the groove mating surface of the annular magnetic yoke and the core column 3. Air gap 4 can also be set on both the core column 3 and the annular magnetic yoke at the same time.

[0124] 5. Coil configuration alternatives: The magnetic yoke coil 6 can be wound only on the first magnetic yoke 1, or only on the second magnetic yoke 2, or both on the top and bottom; the number of turns of each segment of the magnetic yoke coil 6 can be selected as needed, with a minimum of 1 turn; in addition to being connected in series, the core coil 5 and the magnetic yoke coil 6 can also be connected in parallel with taps at specific tap points to achieve adjustable inductance.

[0125] 6. Alternative connection methods for core coil 5: Core coils 5 within the same phase, as well as core coil 5 and yoke coil 6, can be connected in series, in parallel, or in a hybrid series-parallel configuration. By flexibly selecting series or parallel connections, the equivalent inductance, current carrying capacity, and impedance characteristics of each phase winding can be adjusted to meet the application requirements of different voltage levels and current capacities.

[0126] 7. Replacement of the number of core columns 3: As needed, the number of core columns 3 can be two (for single-phase or two-phase systems), three (for three-phase systems) or four or more (for multi-phase systems), and each phase can be composed of multiple sub-core columns 3 connected in parallel.

[0127] 8. Material combination substitution: The annular magnetic yoke uses wound amorphous nanocrystalline ribbon to pursue extremely low loss, and the core column 3 is made of silicon steel sheets to reduce costs; or both use ferrite to adapt to high frequency operating conditions; or the core column 3 uses one material, and the segments of the annular magnetic yoke are spliced ​​with different materials.

[0128] 9. Parallel replacement of sub-core columns 3: Each phase core column 3 can be designed as an integral large-section core column 3, or it can be composed of two or more small core columns 3 connected in parallel. The sub-core columns 3 can be arranged in parallel along the circumferential direction or in the radial direction, and each has a coil wound on it and then connected in parallel to form an equivalent single-phase winding.

[0129] The embodiments of this application have the following beneficial effects:

[0130] 1. Multifunctional integration reduces system costs: A single core can achieve pure differential mode, pure common mode, or differential-common mode integrated functions without the need for an additional common mode choke, significantly reducing the number of components and installation space, and significantly reducing system costs.

[0131] 2. The magnetic circuit can be highly symmetrical and the current balance is excellent (under the preferred scheme): When the core column 3 is evenly arranged at equal angles on the annular magnetic yoke, the length of each phase magnetic circuit is completely equal, which fundamentally eliminates the problems of asymmetry and ineffective half-turns in the planar magnetic circuit. The three-phase inductance imbalance can be controlled within 1.5%, and the current balance and control accuracy are greatly improved.

[0132] 3. It can be efficiently adapted to various high-performance soft magnetic materials with extremely low loss: the main magnetic flux in the ring yoke always flows along the circumference of the ring, and the magnetic flux of the core column 3 flows along the axial direction. Both can be fully matched with the low loss direction of materials such as oriented silicon steel, amorphous, and nanocrystalline. The iron loss can be reduced by 20% to 60% compared with the traditional non-oriented silicon steel three-dimensional reactor.

[0133] 4. High assembly precision and good mechanical stability: The connection method of the grooved annular magnetic yoke and the core column 3 improves the assembly precision, reduces the magnetic resistance fluctuation of the contact surface, enhances the mechanical stability of the overall structure, and facilitates maintenance and replacement.

[0134] 5. Strong heat dissipation capacity and outstanding economy under high current: The coil can be distributed on each section of the core column 3 and the annular yoke, resulting in a large heat dissipation surface area; each phase of the core column 3 can be split into multiple sub-core columns 3 connected in parallel, further dispersing heat and reducing temperature rise. The iron core window has a high utilization rate, allowing for more full utilization of copper and iron materials, and maintaining good economy even under high current and high inductance.

[0135] 6. Flexible electrical connection and strong adaptability: The core coil 5 can be connected in series, in parallel or in a combination of series and parallel, and the magnetic yoke coil 6 can be wound on the top, bottom or both, with a minimum of only 1 turn. It can flexibly match different voltage, current and impedance requirements and has a wide range of applications.

[0136] 7. Serialized and flexible production greatly shortens the development cycle: The standardized "ring yoke + core column 3 + air gap 4" iron core matrix can be quickly configured to adapt to various working conditions, frequencies and functions by changing the coil layout, number of turns, connection method, air gap 4 and material combination. The molds are shared, the derivation cost is extremely low, and it is suitable for flexible manufacturing.

[0137] 8. Excellent Common-Mode Rejection Capability: In the integrated solution, utilizing the efficient zero-sequence magnetic circuit of the gapless 4-ring yoke, the yoke coil 6 provides significant common-mode impedance even with only one turn, resulting in outstanding common-mode interference suppression. Multiple configuration options for the yoke coil 6 can flexibly adapt to cost, space, and performance requirements.

[0138] On the other hand, embodiments of this application provide a method for manufacturing a toroidal magnetic circuit reactor, comprising:

[0139] A core substrate is provided, comprising a first magnetic yoke 1, a second magnetic yoke 2, and at least two core posts 3 arranged at intervals along the circumferential direction and connected to the first magnetic yoke 1 and the second magnetic yoke 2, wherein at least one end of each core post 3 is provided with an air gap 4.

[0140] Based on the target product function, select one of the following coil assembly methods:

[0141] (a) When manufacturing a differential mode reactor, the core coil 5 is wound only on the core 3;

[0142] (b)When manufacturing the differential and common mode integrated reactor, wind the core column coil 5 on the core column 3, and wind the yoke coil 6 around at least one segmented magnetic path of the first yoke 1 and / or the second yoke 2, and connect the core column coil 5 and the yoke coil 6 of the same phase in series;

[0143] (c)When manufacturing the common mode reactor, only wind the yoke coil 6 around at least one segmented magnetic path of the first yoke 1 and / or the second yoke 2.

[0144] Example 1: Basic three-phase pure differential mode reactor

[0145] This example demonstrates a three-phase pure differential mode reactor with high balance, suitable for driving speed control systems.

[0146] Structural description: Refer to Figure 1 and Figure 2 . The iron core consists of the first yoke 1, the second yoke 2 and three core columns 3. Both the first yoke 1 and the second yoke 2 are annular closed rings, wound with grain-oriented silicon steel strips, so that the circumferential direction of the yoke is consistent with the rolling direction of the silicon steel to obtain the lowest iron loss. The three core columns 3 are also laminated with grain-oriented silicon steel sheets, and the lamination direction ensures that the axial magnetic flux of the core column 3 flows along the rolling direction. The three core columns 3 are evenly arranged at equal angles (120°) along the circumference between the first yoke 1 and the second yoke 2, making the three-phase magnetic path lengths completely symmetrical.

[0147] Connection and air gap 4: At the end connection of the first yoke 1, the second yoke 2 and each core column 3, a piece of epoxy resin insulating board with a thickness of δ is padded to form a fixed air gap 4. In this way, there is an air gap 4 at both ends of each core column 3, and the air gap 4 is filled with a non-magnetic insulating gasket.

[0148] Coil configuration: Only one set of core column coils 5 is wound on each core column 3, and the number of turns of the coil is N.

[0149] Analysis of working principle and technical effects: In this structure, the magnetic flux generated by the three-phase symmetric current closes inside the iron core through the air gap 4. The linear magnetic resistance of the air gap 4 dominates the differential mode inductance, and the inductance linearity is excellent. Since the three core columns 3 are evenly arranged at 120° equal angles on the annular yoke, the magnetic path lengths of each phase are exactly equal, fundamentally eliminating the inductance imbalance problem caused by unequal magnetic path lengths in the traditional "day" - shaped planar structure from the magnetic path structure. At the same time, the magnetic flux in the annular yoke always flows along the circumferential tangential direction, and the magnetic flux in the core column 3 flows along the axial direction. Both magnetic flux directions can be consistent with the rolling direction of the grain-oriented silicon steel sheet, thus giving full play to the low-loss characteristics of the grain-oriented material. Compared with the situation where the magnetic flux direction deviates from the rolling direction in the traditional punched sheet stacked three-dimensional structure and non-oriented silicon steel sheets have to be used, the iron core loss under the same working conditions in this example can be significantly reduced.

[0150] Example 2: Differential and Common Mode Integrated Reactor

[0151] Based on the previous embodiment, this embodiment integrates differential-mode and common-mode filtering functions by adding a magnetic yoke coil 6.

[0152] Structural description: The core structure is exactly the same as that in the embodiment.

[0153] Coil configuration: Refer to Figure 3 , Figure 4 , Figure 6 , Figure 7 and Figure 8 This embodiment uses "method (c): simultaneously winding the coils on each segment of the magnetic circuit of the first yoke 1 and the second yoke 2". Taking phase A as an example, on the segment of the first yoke 1 located between the AB core pillars 3, an insulated wire is used to wind an upper yoke coil 6A with m turns through its window; on the corresponding segment of the second yoke 2, a lower yoke coil 6B is wound. Phases B and C are wound in the same way.

[0154] Winding configuration rules: Clockwise is defined as the positive direction of the circumference of the annular yoke. The upper yoke coil 6A of phase A is wound in the direction that generates a clockwise tangential magnetomotive force when a positive current is applied; the upper yoke coil 6 of phase B is also wound in the same direction in its segment to generate a clockwise tangential magnetomotive force; the upper yoke coil 6 of phase C is wound similarly. The yoke coil 6 on the second yoke 2 is also wound in the same direction according to this principle. Then, the core coil 5 of phase A, the upper yoke coil 6A of phase A, and the lower yoke coil 6B of phase A are connected in series in the same direction to form the overall winding of phase A. Phases B and C are similar.

[0155] Simplified Alternative: As a simplified alternative to the embodiment, the magnetic yoke coil 6 can also be arranged in either "Method (a): only wound on each segment of the magnetic circuit of the first magnetic yoke 1" or "Method (b): only wound on each segment of the magnetic circuit of the second magnetic yoke 2," that is, the magnetic yoke coil 6 is wound only on one side of the annular magnetic yoke, and not wound on the other side. In this case, the minimum number of turns of the magnetic yoke coil 6 can be 1 turn, that is, a single wire passes through the magnetic yoke window to form a single-turn electromagnetic coupling. Each phase winding is composed of the core coil 5 connected in series with the single-turn magnetic yoke coil 6. This simplified solution has a simpler manufacturing process and lower cost, and is suitable for applications where there are certain requirements for common-mode rejection, but not extremely high ones.

[0156] Working Principle and Technical Effect Analysis: Under differential mode operation, the three-phase currents are symmetrical, and the combined tangential magnetomotive force of the yoke coil 6 weakens each other, having a negligible impact on the differential mode inductance. The differential mode inductance is still dominated by the air gap 4 of the core column 3. Under common mode operation, the three phases carry currents of the same phase, and the tangential magnetomotive forces generated by all the yoke coils 6 are in the same direction, smoothly closing along the annular yoke without the air gap 4. The magnetic reluctance is extremely low, and the yoke coil 6 exhibits a very large zero-sequence inductance. At the same time, the axial zero-sequence magnetic flux generated by the core column 3 is squeezed out of the air gap 4 and becomes leakage flux because it cannot close within the iron core, contributing very little. The total winding of each phase consists of the core column coil 5 and the yoke coil 6 connected in series, exhibiting a very high common-mode impedance. Differential mode current limiting and common-mode choke are achieved simultaneously using only one set of iron cores. See the magnetic flux path diagram. Figure 6 .

[0157] Example 3: High-current multi-core 3-parallel reactor

[0158] This embodiment is designed for high-current applications, aiming to optimize heat dissipation and improve material utilization.

[0159] Structural description: Refer to Figure 5 Based on the previous embodiment, the original single A-phase core column 3 is replaced with two parallel sub-core columns 3A and 3B arranged along the circumferential direction. The same treatment is applied to phases B and C, that is, each phase core column 3 is composed of two sub-core columns 3 connected in parallel.

[0160] Coil configuration: The same number of turns are wound on each sub-core 3. The coils on two sub-core 3 of the same phase are connected in parallel to form the total winding of that phase.

[0161] Technical Effect Analysis: This design distributes a concentrated high ampere-turns across multiple sub-cores 3, effectively increasing the contact heat dissipation surface area between the coil and the iron core. Because heat can be evenly distributed among the multiple sub-cores 3, it avoids the problem of heat concentration at the center of the core 3, which is difficult to dissipate, as in the single-core-3 design, effectively reducing the winding hot spot temperature. Simultaneously, the parallel connection of multiple sub-cores 3 makes the magnetic flux distribution more uniform across the cross-section of the core 3, increases the core window fill factor, and allows for more efficient utilization of both copper and core materials, resulting in better economic efficiency under high current and high inductance conditions.

[0162] Example 4: A reactor with an air gap 4 installed inside the core column 3.

[0163] This embodiment demonstrates a technical solution where the air gap 4 is located inside the core post 3.

[0164] Structural description: Refer to Figure 9Unlike Embodiment 1, the core column 3 in this embodiment is not a monolithic structure. Taking the A-phase core column 3 as an example, the core column 3 is divided into an upper sub-core segment 3a and a lower sub-core segment 3b along the axial direction, with an insulating pad inserted between them to form an internal air gap 4. The upper and lower ends of the core column 3 are directly and tightly connected to the first magnetic yoke 1 and the second magnetic yoke 2, respectively, and there is no air gap 4 at the ends. The B and C phase core columns 3 adopt the same structure.

[0165] Alternative: The number of air gaps 4 inside the core post 3 can be set multiple as needed. For example, the core post 3 can be divided into three sections along the axial direction to form two internal air gaps 4. The material of the air gaps 4 can be epoxy board, insulating paper, or air gaps.

[0166] Coil configuration: The core coil 5 is wound entirely around the outside of the core 3, which includes the internal air gap 4.

[0167] Technical effect analysis: This structure incorporates the air gap 4, allowing the end face of the core column 3 to be directly and tightly fitted with the annular magnetic yoke, simplifying the assembly process. At the same time, the air gap 4 can still effectively control the magnetic circuit reluctance, achieving the required inductance characteristics.

[0168] Example 5: Reactor with air gap 4 located at the joint of the annular magnetic yoke segments.

[0169] This embodiment demonstrates an alternative to the location of the air gap 4.

[0170] Structural description: Refer to Figure 10 In this embodiment, the first magnetic yoke 1 is composed of three arc-shaped magnetic yoke segments spliced ​​together, with gaps between each segment forming air gaps 4 at the joints of the magnetic yoke segments. The upper and lower ends of the core column 3 are tightly connected to the first magnetic yoke 1 and the second magnetic yoke 2, respectively, and there are no air gaps 4 inside or at the ends of the core column 3.

[0171] Alternative solutions: The second yoke 2 can also adopt the same structure; or the first yoke 1 and the second yoke 2 can both be segmented and spliced ​​with air gaps 4 at the joints; or air gaps 4 can be set at both the end of the core column 3 and the joint of the annular yoke to form a mixed air gap 4 layout.

[0172] Alternative material segmentation: In addition, in the above embodiments, the segmented magnetic circuits of the first magnetic yoke 1 and / or the second magnetic yoke 2 can be constructed by splicing different core materials as needed. For example, some segments are made of amorphous alloy strip wound to achieve extremely low loss, while other segments are made of oriented silicon steel sheets stacked to take cost into account, thereby achieving a flexible balance between performance and cost.

[0173] Technical effect analysis: This solution transfers the air gap 4 from the core column 3 to the annular magnetic yoke, which facilitates precise control of the air gap 4 size during the magnetic yoke assembly process and is suitable for production and manufacturing under specific process conditions.

[0174] Example 6: Modular Configurable Reactor Series

[0175] This embodiment illustrates how to quickly develop a full range of products based on the same iron core platform.

[0176] Iron core platform: Provides a standardized iron core matrix, comprising a first magnetic yoke 1, a second magnetic yoke 2, and a core post 3 with an air gap 4. Both the first magnetic yoke 1 and the second magnetic yoke 2 are closed ring structures.

[0177] Derivation method:

[0178] Product A (Pure Differential Mode Reactor): As in Example 1, only the core coil 5 is assembled to form a differential mode reactor.

[0179] Product B (Differential and Common Mode Integrated Reactor): As in Example 2, a magnetic yoke coil 6 is added and connected in series with the core coil 5 to form a differential and common mode integrated reactor. The magnetic yoke coil 6 can be wound only on the top, only on the bottom, or both on the top and bottom.

[0180] Product C (Pure Common Mode Reactor): This reactor does not have the core coil 5 installed. Instead, yoke coils 6 are wound only on the segmented magnetic circuits of the first yoke 1 and / or the second yoke 2, with the winding direction configured according to the common mode superposition principle, thus forming a pure common mode reactor. The yoke coils 6 can be wound only on the top, only on the bottom, or both on the top and bottom.

[0181] Performance tuning: For all the above products, the inductance and operating frequency can be flexibly adjusted by changing the length of the air gap 4 by replacing the shims of different thicknesses δ, or by changing the number of coil turns, to adapt to different application scenarios.

[0182] Technical effect analysis: This standardized iron core and flexible assembly mode greatly reduces mold investment and design cycle, and realizes serialized flexible production.

[0183] This document uses specific examples to illustrate the principles and implementation methods of this application. The descriptions of the above embodiments are only for the purpose of helping to understand the methods and core ideas of this application. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the ideas of this application. Therefore, the content of this specification should not be construed as a limitation of this application.

Claims

1. A toroidal magnetic circuit reactor, characterized in that, include: First magnetic yoke; The second magnetic yoke is spaced apart from the first magnetic yoke; A core post group, comprising at least two, each core post group comprising at least one core post, and any two core posts being arranged at intervals; One end of the core post is connected to the first magnetic yoke, and the other end is connected to the second magnetic yoke to form a magnetic circuit; At least one air gap is provided in the magnetic circuit formed by the first magnetic yoke, the second magnetic yoke, and the core column; A core coil, including at least one, wherein the core coil is wound on the core.

2. The toroidal magnetic circuit reactor as described in claim 1, characterized in that, The toroidal magnetic circuit reactor further includes a magnetic yoke coil, which includes at least one magnetic yoke coil; the magnetic yoke coil is arranged on the first magnetic yoke and / or the second magnetic yoke. When the yoke coil is arranged on the first yoke and the second yoke, the yoke coil is either two independent coils respectively set on the two yokes, or a common coil that passes through both the first yoke and the second yoke; the yoke coil is formed by a conductor passing through the corresponding yoke window and forming at least one turn of electromagnetic coupling with the yoke; the yoke coil is connected to the core coil on the corresponding toroidal magnetic circuit reactor.

3. The toroidal magnetic circuit reactor as described in claim 2, characterized in that, In each phase, when there are multiple core coils, the multiple core coils are respectively arranged on each core of the phase, and the multiple core coils are connected in series, parallel or mixed manner; when there are multiple magnetic yoke coils in the phase, the multiple magnetic yoke coils are connected in series, parallel or mixed manner; the whole formed by the connection of the magnetic yoke coils in the phase is connected in series with the whole formed by the connection of the core coils in the phase to form a single-phase coil combination; when there are multiple single-phase coil combinations, the multiple single-phase coil combinations belonging to the same phase are connected in parallel.

4. The toroidal magnetic circuit reactor as described in claim 1, characterized in that, The first magnetic yoke, the second magnetic yoke, and the core are each made of one or more soft magnetic materials.

5. The toroidal magnetic circuit reactor as described in claim 4, characterized in that, The first magnetic yoke, the second magnetic yoke, and the core post are each made of one or more of the following materials: oriented silicon steel, non-oriented silicon steel, amorphous alloy, nanocrystalline alloy, nickel-zinc ferrite, and manganese-zinc ferrite.

6. The toroidal magnetic circuit reactor as described in any one of claims 1-5, characterized in that, The first magnetic yoke is a one-piece molded or multi-segment spliced ​​ring structure; and / or, The second magnetic yoke is a ring structure that is integrally formed or spliced ​​from multiple segments.

7. The toroidal magnetic circuit reactor according to any one of claims 1-5, characterized in that, The first magnetic yoke and / or the second magnetic yoke are provided with positioning grooves, and the end of the core post is inserted into the positioning groove; or... The first magnetic yoke and / or the second magnetic yoke are provided with a positioning plane, and the end of the core post abuts against the positioning plane; or, The first yoke and / or the second yoke have protrusions integrally formed thereon, the protrusions forming at least a portion of the core post.

8. The toroidal magnetic circuit reactor as described in any one of claims 1-5, characterized in that, The core pillar group consists of three core pillars, each core pillar group includes one core pillar, and the three core pillars are evenly arranged at equal angles along a circular path.

9. The toroidal magnetic circuit reactor as described in any one of claims 1-5, characterized in that, The toroidal magnetic circuit reactor has one or more air gaps in its magnetic circuit.

10. The toroidal magnetic circuit reactor as described in claim 9, characterized in that, The toroidal magnetic circuit reactor also includes non-magnetic insulating material or weakly magnetic material, which is filled into the corresponding positions to form an air gap.

Images