Core design device, core design method, and computer program product

Abstract

The core design device (100) acquires application parameters including parameters indicating a method for applying a deformation pattern (310a, 310b). The core design device (100) applies the deformation pattern (310a, 310b) to a design target element according to the application method included in the application parameters to change the shape of the design target element. The core design device (100) determines the shape of the core based on a value indicating a characteristic of a device having a core with a changed shape of the design target element when the device is operated.

Description

Technical Field

[0001] The present invention relates to an iron core design device, an iron core design method, and a computer program product, and is particularly suitable for designing an iron core. This application claims priority based on Japanese Patent Application No. 2022-031019 filed on March 1, 2022, the entire contents of which are incorporated herein by reference. Background Art

[0002] In devices with an iron core, such as electric motors, the core's design significantly impacts the device's performance. For example, the rotor shape of an IPMSM (Interior Permanent Magnet Synchronous Motor) is complex. In such a rotor, magnetic flux can be controlled by appropriately placing flux barriers around the permanent magnets embedded in the core. This improves torque characteristics, reduces iron loss, and alleviates stress.

[0003] Therefore, the present inventors have completed the invention described in Patent Document 1. In the invention described in Patent Document 1, the basic shape of at least one design object element is set for the design area as the design object area of ​​the iron core. Then, the algorithm of the optimization problem is used to calculate the optimal solution of the mapping implemented on the basic shape of the design object element. Patent Document 1 describes that in addition to the case where the mapping implemented on the basic shape of the design object element is a linear mapping, it can also be a nonlinear mapping with the same phase. If the mapping implemented on the basic shape of the design object element is set to a nonlinear mapping with the same phase, the search range when searching for the optimal shape of the iron core can be expanded compared to the case where it is a linear mapping.

[0004] Prior art literature

[0005] Patent Literature

[0006] Patent Document 1: Japanese Patent Application Laid-Open No. 2021-114099 Summary of the Invention

[0007] Technical problem to be solved by the invention

[0008] However, Patent Document 1 does not disclose a specific method for the case where the mapping applied to the basic shape of the design object element is set as nonlinear mapping. If nonlinear mapping is applied to the basic shape of the design object element, the shape of the design object element may become overly complex. Therefore, it is possible to obtain a shape that is difficult to realize or a shape that is essentially impossible. On the other hand, when the shape applied to the basic shape of the design object element is too simple, it may be impossible to design a core shape that fully improves the performance of the device. Therefore, it is desirable to search for a core shape that improves the performance of the device from as wide a search range as possible within the achievable range.

[0009] The present invention has been made in view of the above-mentioned problems, and an object of the present invention is to search for a core shape that improves the performance of a device by using a wider search area within an achievable range.

[0010] Technical means for solving technical problems

[0011] The iron core design device of the present invention is an iron core design device that performs calculations related to the design of the shape of the iron core, and comprises: a basic shape acquisition unit that acquires the basic shape of the design object element of the iron core; and an iron core shape determination unit that determines the shape of the iron core by changing the shape of the design object element of the iron core from the basic shape, the iron core shape determination unit having: a deformation pattern acquisition unit that acquires a deformation pattern representing the deformation content of the shape of the design object element; a parameter acquisition unit that acquires application parameters; a design object element changing unit that uses the deformation pattern and the application parameters to change the shape of the design object element; and a characteristic value calculation unit that calculates the characteristic value of the changed shape of the design object element. The shape of the design object element includes a value of a characteristic of the device when the device of the iron core operates; and a determination unit, which determines the shape of the iron core based on the value representing the characteristic of the device, the application parameter includes a parameter representing an application method of the deformation pattern when the deformation pattern is applied to the design object element, the design object element changing unit performs nonlinear mapping on the design object element by applying the deformation pattern to the design object element according to the application method, the deformation pattern represents the displacement of each position in the relative coordinate system on the basic shape of the design object element, and at least one of the deformation patterns represents the deformation content in which the shapes before and after the change become an in-phase mapping relationship.

[0012] The iron core design method of the present invention is an iron core design method for performing calculations related to the design of the shape of the iron core, comprising: a basic shape acquisition step for obtaining the basic shape of the design object element of the iron core; and an iron core shape determination step for determining the shape of the iron core by changing the shape of the design object element of the iron core from the basic shape, the iron core shape determination step comprising: a deformation pattern acquisition step for obtaining a deformation pattern representing the deformation content of the shape of the design object element; a parameter acquisition step for obtaining application parameters; a design object element changing step for changing the shape of the design object element using the deformation pattern and the application parameters; a calculation indicating the deformation content of the design object element; a characteristic value calculation process of the characteristic value of the device when the device of the iron core of the shape is in operation; and a determination process of determining the shape of the iron core based on the value representing the characteristic of the device, the application parameter includes a parameter representing the application method of the deformation pattern when the deformation pattern is applied to the design object element, the design object element change process performs nonlinear mapping on the design object element by applying the deformation pattern to the design object element according to the application method, the deformation pattern represents the displacement of each position in the relative coordinate system on the basic shape of the design object element, and at least one of the deformation patterns represents the deformation content in which the shapes before and after the change become an in-phase mapping relationship.

[0013] The program of the present invention causes a computer to function as each unit of the core design device. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 This is a diagram showing an example of the functional structure of the core design device.

[0015] Figure 2A This is a diagram conceptually showing an example of a process of designing an iron core before setting design target elements.

[0016] Figure 2B This is a diagram showing an example of an element of an iron core, which is a design target element having a set basic shape.

[0017] Figure 3A This is a diagram conceptually showing a first example of a deformation pattern.

[0018] Figure 3B This is a diagram conceptually showing a second example of a deformation pattern.

[0019] Figure 4A This is a diagram conceptually showing a first example of a situation in which a design target element having a basic shape is deformed.

[0020] Figure 4BThis is a diagram conceptually showing a second example of a situation in which a design target element having a basic shape is deformed.

[0021] Figure 5A This is a diagram conceptually showing an example of the first stage of the process of designing an iron core when the shape of a design target element is changed.

[0022] Figure 5B This is a diagram conceptually showing an example of the second stage of the process of designing the core when the shape of the design target element is changed.

[0023] Figure 5C This is a diagram conceptually showing an example of the third stage of the process of designing the core when the shape of the design target element is changed.

[0024] Figure 6A This is a diagram illustrating a first example of overlapping.

[0025] Figure 6B This is a diagram illustrating a second example of overlapping.

[0026] Figure 6C This is a diagram illustrating a third example of overlapping.

[0027] Figure 6D This is a diagram illustrating a fourth example of overlapping.

[0028] Figure 7 is a diagram illustrating an example of overflow.

[0029] Figure 8A is a flow chart illustrating the core design method.

[0030] Figure 8B Then Figure 8A Flowchart of the process.

[0031] Figure 9 This is a diagram showing an example of the hardware configuration of the core design device.

[0032] Figure 10A This is a diagram showing an example of an iron core before design.

[0033] Figure 10B It is a diagram showing a comparative example of a designed iron core.

[0034] Figure 10C This is a diagram showing an example of the invention of a designed iron core. DETAILED DESCRIPTION

[0035] Hereinafter, one embodiment of the present invention will be described with reference to the drawings.

[0036] In addition, in addition to being strictly identical, the length, position, size, and spacing of the comparison objects also include being different within the scope of the invention (for example, different within the range of tolerances determined during design). In addition, in each of the drawings, for ease of description and explanation, the structure is simplified or omitted as needed. In addition, in each of the drawings, xy coordinates are used to represent the relationship between the directions in each figure. The origin of the xy coordinates is not necessarily the position shown in each figure.

[0037] Figure 1 1 is a diagram showing an example of the functional structure of the core design device 100. The hardware of the core design device 100 is realized by using, for example, an information processing device (computer device) including a processor, a main storage device, an auxiliary storage device, and various interfaces, or by using dedicated hardware.

[0038] [Core design device 100]

[0039] The core design device 100 performs calculations related to the design of the shape of the core. Here, the elements of the core include, for example, the core, a tangible object (component or material) arranged inside the core, a space formed inside the core, a space in a recessed portion on the outer periphery of the core, and a space in a recessed portion on the inner periphery of the core. A portion of the tangible object (component or material) arranged inside the core may also be exposed on the surface of the core. Not only the area of ​​the core (the area of ​​magnetic material such as electromagnetic steel plate), but also the area of ​​the tangible object (area of ​​component or material) arranged inside the core, the space formed inside the core, the space in a recessed portion on the outer periphery of the core, and the space in a recessed portion on the inner periphery of the core are elements of the core, and not all of them need to be elements of the core.

[0040] exist Figure 1 In the embodiment, the core design device 100 includes a design source information acquisition unit 110 , a basic shape acquisition unit 120 , a core shape determination unit 130 , and an output unit 140 .

[0041] <Design Source Information Acquisition Unit 110>

[0042] The design source information acquisition unit 110 acquires information about the core of the design object. The information about the core of the design object is information that the core design device 100 needs to prepare in advance in order to perform calculations related to the design of the core. In this embodiment, the design source information acquisition unit 110 obtains information about the core of the design object, including information about the design area as the design object area of ​​the core, information about the elements of the core other than the design object elements, and information about the physical property values ​​of each element of the core. The design object element refers to an element of the elements of the core that requires design attributes such as shape, position, and size. The design object element is determined by a designer or the like. The information about the design area is information required to uniquely determine the design area, for example, including information that can uniquely determine the shape, size, and position of the design area. Similarly, the information about the elements of the core other than the design object elements is information required to uniquely determine the area of ​​the elements of the core other than the design object elements, including information that can uniquely determine the shape, size, and position of the elements of the core other than the design object elements.

[0043] Figure 2A and Figure 2B This is a diagram conceptually showing an example of the process of designing an iron core before the shape of the design object element is changed. In this embodiment, the case of designing the shape of the rotor of the IPMSM is illustrated. In addition, in this embodiment, the case of designing the two-dimensional shape of a cross section cut perpendicularly to the center line of the IPMSM is illustrated. Figure 2A and Figure 2B In the figure, the cross section perpendicular to the center line of the IPMSM is the xy plane.

[0044] In this embodiment, the rotor core of the IPMSM is exemplified as including an iron core, permanent magnets disposed within the iron core, and flux barriers formed within the iron core. Therefore, in this embodiment, the rotor core comprises the iron core, permanent magnets, and flux barriers. Figure 2A and Figure 2BThe area shown is a cross section of the IPMSM rotor, and is one of four areas divided into four equal parts by cutting the cross section perpendicular to the center line of the IPMSM. These four areas have a four-fold symmetry. Therefore, by designing only one of these four areas, it is possible to design the entire cross section of the IPMSM rotor, i.e., the cross section cut perpendicular to the center line of the IPMSM. That is, in one of these four areas, the iron core, permanent magnets, and flux barriers are designed. Then, the iron core, permanent magnets, and flux barriers designed in one of the four areas are rotated 90°, 180°, and 270° with the center line of the IPMSM as the rotation axis. In this way, it is possible to design the entire cross section of the IPMSM rotor, i.e., the cross section cut perpendicular to the center line of the IPMSM. In addition, the flux barrier is assumed to be space (air). However, the flux barrier does not have to be space. For example, the flux barrier can also be composed of a non-magnetic material.

[0045] This embodiment illustrates the case where the flux barriers, among these core elements, are design elements. However, this embodiment also includes a description of the consideration of permanent magnets as design elements in addition to the flux barriers. Thus, when designing an IPMSM rotor, for example, at least one of the flux barriers and the permanent magnets can be a design element.

[0046] Figure 2A This is a diagram showing an example of the elements of the core before setting the design target elements.

[0047] exist Figure 2A In the example shown, the design area 200 is the area surrounded by the outer edge of the core area 210. Figure 2A As shown, the shape of the outer edge of the region 210 of the core is an annular sector with a central angle of 90 degrees. In this embodiment, the coordinates of the area surrounded by the outer edge of the region 210 of the core are included in the information of the design region 200. The design source information acquisition unit 110 obtains such information of the design region 200 and sets it in the main storage device (operating area). In addition, the design source information acquisition unit 110 obtains identification information ID1 for distinguishing the design region 200 from other regions, and sets each coordinate of the design region 200. In the following description, the region 210 of the core is referred to as the core 210 as needed.

[0048] exist Figure 2A In the example shown, the core elements other than the design target elements are permanent magnets. Figure 2A In the example shown, the region of the core elements other than the design target element is the region surrounded by the outer edge of the permanent magnet region 220. Figure 2AAs shown, the shape of the outer edge of the region 220 of the permanent magnet is a rectangle. In the present embodiment, an example is given of a situation where the coordinates of the region surrounded by the outer edge of the region of the elements of the iron core other than the design object elements (region 220 of the permanent magnet) are information of the elements of the iron core other than the design object elements. The design source information acquisition unit 110 obtains the information of such a region 220 of the permanent magnet and sets the design region 200. In addition, the design source information acquisition unit 110 obtains the identification information ID2 of the region and other elements (regions) for identifying the elements of the iron core other than the design object elements, and sets each coordinate of the region of the elements of the iron core other than the design object elements. In addition, when there are multiple elements of the iron core other than the design object elements, the design source information acquisition unit 110 sets different identification information ID2 according to the type of the elements of the iron core other than the design object elements. In the following description, the region of the elements of the iron core other than the design object elements is referred to as the elements of the iron core other than the design object elements, and the region 220 of the permanent magnet is referred to as the permanent magnet 220 as needed.

[0049] In addition, the design source information acquisition unit 110 acquires identification information ID3 for identifying the design object element and other elements (regions). In addition, when there are multiple design object elements, the design source information acquisition unit 110 acquires different identification information ID3 according to the type of design object element. As described above, in this embodiment, the case where the magnetic flux barrier formed in the core of the rotor of the IPMSM is a design object element is exemplified. Figure 2A In the stage shown, no flux barrier is set in the core 210. Therefore, Figure 2A In the illustrated stage, the identification information ID3 is not set in the core 210 .

[0050] In addition, the design source information acquisition unit 110 acquires information indicating the physical property values ​​of each element of the core. Figure 2A and Figure 2B In the example shown, the physical properties of the various elements of the core include the physical properties of the magnetic material such as the electromagnetic steel sheet constituting the core 210, the physical properties of the permanent magnet 220, and the physical properties of the flux barrier (air or non-magnetic material) as an example of a design object element.

[0051] In this embodiment, the designer inputs information about the design area 200, information about core elements other than the design target elements, information indicating the physical property values ​​of each core element, and identification information ID1 to ID3 into the core design device 100 by operating the core design device 100's user interface. In this case, the design source information acquisition unit 110 acquires the information input into the core design device 100 via the core design device 100's user interface, for example. However, the method by which the design source information acquisition unit 110 acquires this information is not limited to this method. For example, an external device such as a computer connected to the core design device 100 via a communication network may transmit this information to the core design device 100, and the design source information acquisition unit 110 may acquire this information by receiving this information using the communication interface. Alternatively, the design source information acquisition unit 110 may acquire this information from a storage device included in the core design device 100.

[0052] Furthermore, the design source information acquisition unit 110 may automatically generate the identification information ID1 to ID3.

[0053] <Basic Shape Acquisition Unit 120>

[0054] The basic shape acquisition unit 120 acquires information on the basic shape of a design element and sets the basic shape of the design element in the design area 200. The basic shape information of the design element includes, in addition to the specific shape of the design element, information that uniquely identifies its size and initial position. In this embodiment, the coordinates of each position of the outer edge of the area of ​​the basic shape design element are included in the basic shape information of the design element. A basic shape is, for example, a shape that is assumed to be the shape of the design element. To prevent the final calculated shape from becoming overly complex, a simple shape such as a circle or rectangle is preferably used. The number of basic shapes is arbitrary and can be one, two, or three or more. When multiple basic shapes are set, each basic shape can be the same or different. The position and size of the basic shapes are not limited as long as they are located within the design area 200. When multiple basic shapes are set, the positions of the multiple basic shapes are separated from each other.

[0055] As described above, this embodiment illustrates the case where the design element is a flux barrier. In an IPMSM rotor, the core 210 is not surrounded by the flux barrier (i.e., the core does not float within the flux barrier). Therefore, the basic shape of the design element is preferably set so that no elements of a different type than the design element are contained within it.

[0056] Figure 2BThis is a diagram showing an example of an element of an iron core, which is a design target element having a set basic shape.

[0057] exist Figure 2B In the example, two basic shapes are set at separate locations as the basic shapes of the design target elements. The basic shape acquisition unit 120 sets the coordinates of the areas 230a and 230b of the basic shape design target elements in the design area 200. The basic shape acquisition unit 120 changes the identification information ID1 set for the coordinates of the areas 230a and 230b of the basic shape design target elements to identification information ID3 used to distinguish the area of ​​the design target element from other areas. In the following description, the areas 230a and 230b of the basic shape design target elements are referred to as the basic shape design target elements 230a and 230b as needed.

[0058] In this embodiment, a case is exemplified in which a designer inputs information of the basic shape design target elements 230a and 230b to the core design device 100 by operating the user interface of the core design device 100. For example, the basic shape acquisition unit 120 acquires the information of the basic shape design target elements 230a and 230b input to the core design device 100 via the user interface of the core design device 100. More specifically, for example, the basic shape acquisition unit 120 acquires the information of the basic shape design target elements 230a and 230b Figure 2A A graphical user interface (GUI) showing an image of the core elements is displayed on a computer monitor. This GUI allows the user to specify areas of the design region 200 other than the permanent magnet 220 within the image of the core elements by operating the user interface of the core design device 100. By making these designations, the designer inputs information on the basic shapes of the design target elements 230a and 230b into the core design device 100.

[0059] However, the method by which the basic shape acquisition unit 120 acquires information about the basic shape design target elements 230a and 230b is not limited to this method. For example, the external device may transmit information about the basic shape design target elements 230a and 230b to the core design device 100, and the basic shape acquisition unit 120 may receive the information about the basic shape design target elements 230a and 230b using a communication interface. Alternatively, the basic shape acquisition unit 120 may acquire information about the basic shape design target elements 230a and 230b from a storage device included in the core design device 100.

[0060] <Core Shape Determination Unit 130>

[0061] The core shape determination unit 130 determines the shape of the core. In this embodiment, the core shape determination unit 130 determines the shape, position, and size of the design elements 230a and 230b in the design region 200 by modifying the shapes of the design elements 230a and 230b from their basic shapes. Furthermore, in this embodiment, the core shape determination unit 130 includes a deformation pattern acquisition unit 131, a parameter acquisition unit 132, a design element modification unit 133, a characteristic value calculation unit 134, and a determination unit 135.

[0062] <<Deformation Pattern Acquisition Unit 131>>

[0063] The deformation pattern acquisition unit 131 acquires a deformation pattern representing the deformation of the design element's shape. The deformation pattern represents the displacement of each position in the relative coordinate system relative to the basic shape of the design element. Furthermore, at least one deformation pattern can be acquired, wherein the at least one deformation pattern represents a deformation such that the shapes before and after the change are in phase with each other. An example of a deformation pattern is described below.

[0064] As described in the "Technical Problem to be Solved by the Invention" section, if nonlinear mapping is applied to the basic shape of a design element, the shape of the design element may become overly complex. This may result in the shapes before and after deformation not being in phase (isomorphic). On the other hand, if the shape resulting from nonlinear mapping of the basic shape of the design element is overly simple, it may be impossible to design a core shape that improves device performance.

[0065] Here, a linear map is a map that satisfies additivity and homogeneity. A nonlinear map is a map that is not a linear map. An in-phase map is a map that satisfies the conditions that the mapping between two phase spaces is bijective and continuous, and that its inverse is continuous. When an in-phase map exists, the two phase spaces are in phase. Furthermore, the concepts of linear, nonlinear, and in-phase maps are the same as those generally used in mathematics.

[0066] When a nonlinear mapping is applied to a design object element, it is necessary to use certain parameters to express the nonlinear mapping. Therefore, it is desirable to use parameters that take into account both the preservation of the same phase of the mapping and the assurance of the arbitrariness of the shape within the range envisioned as the core. Regarding this point, no specific parameters are disclosed in Patent Document 1. Therefore, the present inventors, on the basis of preparing a deformation pattern representing the displacement of each position in the relative coordinate system on the basic shape of the design object element, envisioned a method for searching for an application of the deformation pattern that improves the characteristics of the device (IPPMSM in this embodiment). In this way, the basic shape of the design object element can be flexibly changed. Therefore, within the achievable range, a wider range than the technology described in Patent Document 1 is used as the search area, and the shape of the core that improves the performance of the device can be searched. In addition, by using the deformation pattern to change the shape of the design object element, the design object element can be gradually deformed. Therefore, by repeatedly applying the deformation pattern to the design object element (i.e., repeatedly using the contents shown in the deformation patterns 310a and 310b to change the shape of the design object element), it is possible to search from a wide search area for the shape of the design object element that improves the characteristics of the device (IPMSM in this embodiment) within the range assumed as the iron core.

[0067] Furthermore, the inventors of the present invention have come up with the idea of ​​setting the deformation content shown in the deformation pattern to a deformation content in which the shapes before and after the change become an in-phase mapping relationship, thereby taking into account both the preservation of the in-phase nature of the mapping and the assurance of the arbitrariness of the shape within the range assumed as the iron core.

[0068] If the deformation content shown in the deformation pattern is set to a deformation content that causes the shapes before and after the change to be in phase, then by using the deformation pattern to change the shape of the design target element, the design target element before and after the deformation will be in phase. Therefore, by repeatedly applying such a deformation pattern to the design target element (i.e., repeatedly using the content shown in deformation patterns 310a and 310b to change the shape of the design target element), the in-phase relationship of the design target element before and after the deformation can be maintained, and the shape of the design target element that improves the characteristics of the device (in this embodiment, the IPMSM) within the range assumed as the core can be searched from a wide search area.

[0069] When the design elements before and after deformation are not in phase with each other, for example, the deformed design element may be twisted relative to the pre-deformed design element so that it includes an intersection (for example, forming an Arabic numeral 8). Furthermore, when the design elements before and after deformation are not in phase with each other, for example, a single pre-deformed design element may become multiple design elements. For example, if the design element is a flux barrier, it is possible to design a core that includes multiple flux barriers. On the other hand, for example, when a circle is changed to a polygon, the number of polygon corners is changed, a bend point is changed to a curve, and the curvature of the curved portion is changed, the design elements before and after the change are in phase with each other. Therefore, deforming the design element so that the pre-deformed design element is in phase with each other is preferable because it can prevent the design of a core that is difficult to manufacture or essentially impossible, or the design of a core that does not meet performance requirements (for example, mechanical and magnetic properties). However, even if the pre-deformed design elements are not in phase with each other, it is possible that the designed core can be manufactured and meet performance requirements. For example, increasing the number of flux barriers is sometimes acceptable, as long as it is not excessive. Therefore, the design target elements before and after deformation do not necessarily need to be in an in-phase mapping relationship.

[0070] In addition, when there are multiple deformation patterns as deformation patterns, the shape of the design object element after deformation changes according to the order in which the multiple deformation patterns are applied. Therefore, by changing the order in which the multiple deformation patterns are applied to the design object element (i.e., changing the order of the multiple deformation patterns 310a and 310b used when changing the shape of the design object element), it is possible to search for the shape of the design object element that improves the characteristics of the device (in this embodiment, the IPMSM) within the range assumed as the iron core from a wide search area. At this time, the content of the deformation shown in the deformation pattern is set to the content of the deformation in which the shapes before and after the change are in phase mapping. Therefore, it is possible to preserve the phase of the design object element before and after the deformation, and to search for the shape of the design object element that improves the characteristics of the device (in this embodiment, the IPMSM) within the range assumed as the iron core from a wide search area.

[0071] Furthermore, by combining the repeated application of deformation patterns to the design target element and varying the order of application to apply multiple deformation patterns to the design target element, it is possible to search for a design target element shape that further improves the characteristics of the device (in this embodiment, the IPMSM) across a wider search area. In this case, the deformation content shown in the deformation pattern is set to a deformation content that forms an in-phase mapping relationship between the shapes before and after the change. Therefore, while preserving the in-phase relationship between the design target element before and after the deformation, it is possible to search for a design target element shape that further improves the characteristics of the device (in this embodiment, the IPMSM) across a wider search area.

[0072] When applying a deformation pattern to a design element as described above, it is preferable that the amount of change in the shape of the design element resulting from a single application of the deformation pattern be small. Since the design element can be gradually deformed, it is possible to search for a design element shape that further improves device characteristics. The following description illustrates and illustrates a case where the deformation shown in the deformation pattern is such that the shapes before and after the change are in phase with each other.

[0073] Figure 3A and Figure 3B This is a diagram conceptually showing an example of the deformed patterns 310a and 310b. Figure 3A 310a is a diagram showing a first example of the deformation pattern 310a. Figure 3B 310 b is a diagram showing a second example of the deformation pattern 310 b . Figure 4A and Figure 4B 310a and 310b are conceptually shown as an example of a situation in which the basic-shaped design target elements 230a and 230b are deformed by applying deformation patterns 310a and 310b to the basic-shaped design target elements 230a and 230b. Specifically, Figure 4A It is a conceptual representation of Figure 3A The deformation pattern 310a shown is applied to the basic shape design object element 230, and is an example of a case where the basic shape design object element 230 is deformed like the area 240a of the design object element. Figure 4B It is a conceptual representation of Figure 3B The diagram illustrates an example of a situation in which a deformation pattern 310b is applied to a basic-shaped design target element 230, deforming the basic-shaped design target element 230 as shown in region 240b of the design target element. In the following description, regions 240a and 240b of the design target element are referred to as modified design target elements 240a and 240b based on the deformation patterns 310a and 310b, or simply as modified design target elements 240a and 240b, as appropriate.

[0074] exist Figure 3Aand Figure 3B In the figure, the grid-shaped area represented by the dotted line is the area of ​​the deformation pattern 310a, 310b applied to the design object element. In the following description, this area is referred to as the deformation pattern application area 320a, 320b as needed. The arrow line extending from the position of the grid represented by the dotted line represents a displacement vector, which represents the content of the displacement when the part of the design object element overlapping with the position is displaced. The length of the arrow line represents the size of the displacement vector. In addition, the direction of the arrow line represents the direction of the displacement vector. Each displacement vector can be set to any size (length) and direction (angle) within the range that does not affect the phase. Therefore, as a shape change of the design object element, a shape displacement that cannot be expressed by matrix operation can be expressed. Therefore, as a shape change of the design object element, a shape change with a high degree of freedom can be realized. The displacement shown by each displacement vector is the displacement of each position in the relative coordinate system on the basic shape of the design object element. The relative coordinates on the basic shape of the design object element are coordinates based on the specified position (coordinates) of the outer edge of the design object element of the basic shape. In Figure 4A and Figure 4B In the example shown, the displacement in the relative coordinate system relative to the basic shape of the design element is based on a position aligned with the grid indicated by the dashed lines, among the positions of the outer edge of the basic shape of the design element 230. Thus, in this embodiment, the deformed patterns 310a and 310b are shown as examples of representing the displacement vector for each position in the relative coordinate system relative to the basic shape of the design element. However, the deformed patterns 310a and 310b do not need to represent the displacement vectors themselves, as long as they represent the displacement for each position in the relative coordinate system relative to the basic shape of the design element. For example, they may include information that can identify the displacement vectors (e.g., displacements along each axis of the relative coordinate system).

[0075] exist Figure 3A and Figure 3B In the figure, for the sake of convenience, the displacement vector is shown only at the position of the grid indicated by the dotted line. However, such a displacement vector may be set in all coordinates of the deformation pattern application areas 320a and 320b. For example, it is also possible to use the four vertices of a grid indicated by the dotted line (for example, Figure 3AThe displacement vectors of the coordinates of the area of ​​the grid are calculated by interpolating the displacement vectors set for the vertices 330a to 330d of the grid. Interpolation is performed, for example, by calculating the weighted average of the displacement vectors set for the four vertices. For example, as the displacement vector of a certain coordinate in a certain grid, the weighted average of the displacement vectors of the four vertices of the grid is calculated. The weight used in calculating the weighted average (that is, the weight of the displacement vectors for the four vertices of the grid) is set to a larger value the shorter the distance from the vertex to the coordinate. In addition, the interpolation method itself can be implemented by a well-known method and is not limited to the above method.

[0076] As described above, in this embodiment, the case where information indicating the displacement vector at each coordinate of the deformation pattern application region 320 a , 320 b is included in the deformation patterns 310 a , 310 b is exemplified.

[0077] like Figure 4A and Figure 4B As shown in the figure on the left side of , in this embodiment, an example is shown in which the deformed pattern application areas 320a and 320b are set for the design object element 230 of the basic shape so that the center of gravity position 0 of the design object element 230 of the basic shape is consistent with the center position 0 of the deformed pattern application areas 320a and 320b of the deformed patterns 310a and 310b, thereby applying the deformed patterns 310a and 310b to the design object element 230 of the basic shape.

[0078] In this manner, when deformed pattern application areas 320a and 320b are set on a basic-shaped design object 230, the coordinates of the outer edge of the basic-shaped design object 230 are changed based on the displacement vectors set at coordinates within the deformed pattern application areas 320a and 320b that coincide with the coordinates of the outer edge of the basic-shaped design object 230. This change in the coordinates of the outer edge of the basic-shaped design object 230 is performed on the coordinates of the outer edge of the basic-shaped design object 230. Therefore, the size of the deformed pattern application areas 320a and 320b is preferably larger than the size assumed for the basic-shaped design object 230. This is because all coordinates of the outer edge of the basic-shaped design object 230 can be changed.

[0079] exist Figure 4A In the example shown, by Figure 3AThe deformation pattern 310a shown is applied to the basic shape design object element 230, and the basic shape design object element 230 becomes the modified design object element 240a based on the deformation pattern 310a. In this case, the shapes of the design object elements before and after deformation (the basic shape design object element 230 and the modified design object element 240a based on the deformation pattern 310a) have an in-phase mapping relationship and a nonlinear mapping relationship. Similarly, as Figure 4B As shown, by Figure 3B In the example, deformation pattern 310b is applied to basic-shaped design target elements 230a and 230b, transforming basic-shaped design target element 230 into a modified design target element 240b based on deformation pattern 310b. In this case, the shapes of the design target elements before and after deformation (basic-shaped design target element 230 and modified design target element 240b based on deformation pattern 310b) have both an in-phase mapping relationship and a nonlinear mapping relationship.

[0080] like Figure 4A As shown, Figure 3A Deformation pattern 310a shown is intended to deform the area on the positive side of the y-axis of the basic design element more significantly toward the positive side of the x-axis as the coordinates on the positive side of the y-axis become closer. Using these deformation patterns 310a and 310b, nonlinear mapping that significantly bends the basic design element can be achieved in a single operation (mapping).

[0081] In addition, Figure 4B In the example shown, Figure 3B The deformation pattern 310b shown is a deformation pattern that is intended to change the area on the positive side of the y-axis of the basic shape more toward the positive side of the y-axis as the coordinates are closer to the center of the x-axis. Figure 4B The deformation pattern 310b shown is a deformation pattern in which the direction of the displacement vector of the deformation pattern application area 320b is reversed (toward the negative y-axis direction (downward)). In this case, the basic design element 230 is modified to a shape in which a portion of the basic design element 230 is contracted (depressed).

[0082] As described above, by using the deformation patterns 310a and 310b, nonlinear mapping that expands or contracts a portion of the design element can be achieved in one operation (mapping). Furthermore, the nonlinear mapping that expands or contracts a portion of the design element can be made into an in-phase mapping.

[0083] In addition, Figure 4A and Figure 4BIn the figure, the design elements 240a and 240b after deformation based on the deformation patterns 310a and 310b are exaggerated to facilitate understanding of the deformation. That is, the design elements 240a and 240b after deformation based on the deformation patterns 310a and 310b are not strictly aligned with the displacement vectors shown by the deformation patterns 310a and 310b.

[0084] As described above, based on the deformation content of the deformation patterns 310a, 310b (information indicating the deformation content included in the deformation patterns 310a, 310b), a portion or the entire outer edge of the area of ​​the design object element (in this embodiment, the flux barriers 230a, 230b) is referenced. Figure 3A and Figure 3B The basic deformation method described above is predetermined. In this embodiment, the deformation content based on the deformation patterns 310a and 310b is determined by the size of the deformation pattern application areas 320a and 320b and the displacement vectors at each coordinate of the deformation pattern application areas 320a and 320b. The type of deformation used as the basic deformation is predetermined based on the type of design element, etc.

[0085] In addition, Figure 3A and Figure 3B The example in FIG. 1 illustrates a case where the vertices of the grid indicated by dotted lines include vertices not shown by arrows. This indicates that no displacement vector is set for the vertex not shown by arrows (in other words, a displacement vector of magnitude 0 (zero) is set for that vertex). As described above, displacement vectors do not need to be set for all coordinates in the deformation pattern application areas 320a and 320b. However, displacement vectors may be set for all coordinates in the deformation pattern application areas 320a and 320b.

[0086] In addition, Figure 3A and Figure 3B The example in FIG. 3 illustrates the case where the displacement vectors are set in the same direction for all coordinates in the deformation pattern application areas 320a and 320b. This case is similar to setting the coordinates in the same direction (in Figure 3A The positive direction of the x-axis is Figure 3B The positive direction of the y-axis corresponds to the change. However, this is not necessarily required. For example, displacement vectors in different directions may be set in the deformation pattern application areas 320a and 320b. However, it is preferred that the deformation content based on the displacement vector be determined so that the shapes of the design element before and after deformation are in phase mapping in a single deformation using the deformation patterns 310a and 310b.

[0087] In this embodiment, the deformation pattern acquisition unit 131 acquires and stores information on a plurality of deformation patterns 310a and 310b as described above. However, the deformation pattern acquisition unit 131 may acquire information on a single type of deformation pattern 310a and 310b. The information on the deformation patterns 310a and 310b is necessary to uniquely identify the content of the deformation based on the deformation patterns 310a and 310b. In this embodiment, the deformation pattern information includes information on displacement vectors at each coordinate of the deformation pattern application areas 320a and 320b. Furthermore, if at least a portion of the content of the deformation represented by the plurality of deformation patterns 310a and 310b differs, the plurality of deformation patterns 310a and 310b become different types of deformation patterns 310a and 310b. In this embodiment, if at least one of the magnitude and direction of the displacement vector differs at at least one coordinate in the deformation pattern application areas 320a and 320b, the multiple deformation patterns 310a and 310b become different types of deformation patterns 310a and 310b. Alternatively, there may not be multiple types of deformation patterns (i.e., the deformation pattern may be a single type).

[0088] Furthermore, the preferred basic deformation based on the deformation patterns 310a and 310b varies depending on the type of design element, etc. Furthermore, for example, in some cases, the core design device 100 repeatedly performs core design, and a preferred basic deformation based on the deformation patterns 310a and 310b is later determined. Therefore, the deformation pattern acquisition unit 131 may acquire the deformation patterns 310a and 310b again after acquiring them (i.e., it may update the deformation patterns 310a and 310b as appropriate).

[0089] In this embodiment, a case is described in which a designer inputs information about the deformation patterns 310a and 310b into the core design device 100 by operating the user interface of the core design device 100. In this case, the deformation pattern acquisition unit 131, for example, acquires the information about the deformation patterns 310a and 310b input to the core design device 100 via the user interface of the core design device 100. However, the method by which the deformation pattern acquisition unit 131 acquires information about the deformation patterns 310a and 310b is not limited to this method. For example, an external device may transmit information about the deformation patterns 310a and 310b to the core design device 100, and the deformation pattern acquisition unit 131 may acquire information about the deformation patterns 310a and 310b by receiving the information using a communication interface.

[0090] <<Parameter Acquisition Unit 132>>

[0091] The parameter acquisition unit 132 acquires application parameters. The application parameters include parameters indicating the application method of the deformed patterns 310a, 310b when applying the deformed patterns 310a, 310b to the design target element. As described later, in this embodiment, the design target element changer 133 applies the deformed patterns 310a, 310b to the design target element to change the shape of the design target element according to the application method of the deformed patterns 310a, 310b included in the application parameters acquired by the parameter acquisition unit 132.

[0092] As described above, by combining and repeatedly applying deformation patterns 310a and 310b to a design element and varying the order of application, multiple deformation patterns 310a and 310b are applied to the design element, thereby changing the shape of the design element. This allows the homogeneity of the design element before and after deformation to be preserved, and allows a wider search area to be searched for a design element shape that further improves the characteristics of the device (in this embodiment, the IPMSM). Therefore, in this embodiment, the method for applying deformation patterns 310a and 310b includes the type of deformation pattern 310a and 310b applied to the design element, the number of times the deformation pattern 310a and 310b is repeatedly applied to the design element, and, if multiple deformation patterns 310a and 310b are applied to the design element, the order in which the multiple deformation patterns 310a and 310b are applied.

[0093] In the following description, the type of deformed pattern 310a, 310b applied to a design element is referred to as the type of deformed pattern 310a, 310b, or simply as the type, as needed. Furthermore, the number of times a deformed pattern 310a, 310b is repeatedly applied to a design element is referred to as the number of applications of the deformed pattern 310a, 310b, or simply as the number of applications, as needed. Furthermore, the order in which the deformed patterns 310a, 310b are applied to a design element is referred to as the order in which the deformed patterns 310a, 310b are applied, or simply as the order in which they are applied. The method for applying the deformed patterns 310a, 310b is not limited to the type, number of applications, and order of application of the deformed patterns 310a, 310b. For example, the method for applying the deformed patterns 310a, 310b may include only either the number of applications or the order in which the deformed patterns 310a, 310b are applied. Furthermore, for example, a method of repeatedly applying a plurality of deformed patterns 310 a and 310 b once each may be included in the method of applying the deformed patterns 310 a and 310 b .

[0094] In addition, this embodiment illustrates a case where application parameters, including the type, number of applications, and order of application of the deformation patterns 310a and 310b, are used as optimization parameters. In addition, this embodiment illustrates a case where the core shape determination unit 130 uses an optimization problem algorithm to calculate the optimal solution for the optimization parameters. More specifically, this embodiment illustrates a case where a genetic algorithm, one of the metaheuristic methods, is used as the optimization problem algorithm. Thus, this embodiment illustrates a case where the application parameters are variable parameters and the deformation patterns 310a and 310b are fixed parameters. Furthermore, a variable parameter means that its content can be changed during the process of determining the core shape. A fixed parameter means that its content does not change during the process of determining the core shape. Specifically, this embodiment illustrates a case where the application parameters are changed during the search for the optimal solution for the optimization parameters. On the other hand, this embodiment illustrates a case where the deformation patterns 310a and 310b do not change during the search for the optimal solution for the optimization parameters.

[0095] In addition, in this embodiment, the case where the parameters for implementing linear mapping (affine transformation) are also included in the optimization parameters in addition to the application parameters is illustrated. In the following description, the parameters for implementing linear mapping (affine transformation) will be referred to as linear mapping parameters as needed. In this way, if linear mapping is also implemented on the design object elements in addition to deformation based on the deformation pattern, the time for searching for the optimal solution of the optimization parameters (type of deformation patterns 310a, 310b, application parameters, and application order) can be shortened. Therefore, if the calculation time is the same when the linear mapping parameters are included in the optimization parameters and when the linear mapping parameters are not included in the optimization parameters, the former case can search for the optimal solution from a wider search area than the latter case.

[0096] As described above, this embodiment illustrates a case where the type, number of applications, and order of applications of the deformation patterns 310a and 310b, as well as the parameters of the linear mapping, are included in the optimization parameters (application parameters). Furthermore, this embodiment illustrates a case where the core shape determination unit 130 calculates the optimal solution for the optimization parameters using a genetic algorithm.

[0097] In the present embodiment, the parameter acquisition unit 132 calculates candidate solutions for the optimization parameters. One candidate solution for the optimization parameters includes the type of deformation patterns 310a, 310b, application parameters and application order, and parameters of the linear mapping. In the present embodiment, the parameter acquisition unit 132 calculates a plurality of candidate solutions as such candidate solutions for the optimization parameters. In addition, the number of candidate solutions for the optimization parameters acquired by the parameter acquisition unit 132 may also be one. In addition, the initial values ​​of the candidate solutions for the optimization parameters are set, for example, by a well-known method using a genetic algorithm. The initial values ​​of the candidate solutions for the optimization parameters are randomly set using, for example, random numbers. In addition, the types of deformation patterns 310a, 310b included in the optimization parameters are selected from the deformation patterns 310a, 310b acquired by the deformation pattern acquisition unit 131 (see Figure 3A and Figure 3B ). In addition, an upper limit may be set for the number of types of deformation patterns 310a and 310b included in the optimization parameters and the number of times they are applied. In addition, when calculating the candidate solutions of the optimization parameters for the second and subsequent times, the parameter acquisition unit 132 updates the candidate solutions of the optimization parameters that have already been calculated using the genetic algorithm.

[0098] Here, an example of linear mapping parameters is described.

[0099] The xy coordinates of the outer edge of the region of the design target element before mapping (for example, the basic-shaped design target elements 230a and 230b) are represented by (x, y). Thus, the xy coordinates (x', y') of the outer edge of the region of the design target element after mapping is represented by the following equation (1).

[0100] [Formula 1]

[0101]

[0102] When the mapping is a linear mapping, the components a, b, c, d, e, and f of the matrix of formula (1) are real numbers (numerical values). When the mapping is a linear mapping, the mapping is obtained by obtaining these components a to f. Therefore, the parameters of the linear mapping include the values ​​of the components a to f. That is, one of the combinations of the values ​​of the components a to f is a parameter of the linear mapping. In addition, the linear mapping itself is implemented as described in Patent Document 1. Therefore, a detailed description of the linear mapping is omitted here.

[0103] <<Design Element Changing Unit 133>>

[0104] The design element changing unit 133 changes the shape of the design element using the deformation patterns 310a, 310b and the application parameters. In this embodiment, the design element changing unit 133 applies the deformation patterns 310a, 310b to the design element according to the application method of the deformation patterns 310a, 310b included in the application parameters acquired by the parameter acquiring unit 132, thereby performing nonlinear mapping on the design element.

[0105] As described above, this embodiment illustrates a case where the application method of the deformation patterns 310a and 310b and the parameters for linear mapping are included in the application parameters (optimization parameters). Therefore, in this embodiment, the design object element changing unit 133 performs the following operations: applying the deformation patterns 310a and 310b to the design object element according to the application method of the deformation patterns 310a and 310b to change the shape of the design object element; and performing linear mapping on the design object element. Here, if the shape of the design object element is changed according to the content indicated by the deformation patterns 310a and 310b after linear mapping, the design object element subjected to linear mapping may become larger than the deformation pattern application areas 320a and 320b. Therefore, this embodiment illustrates a case where, after the shape of the design object element is changed by applying the deformation patterns 310a and 310b to the design object element according to the application method of the deformation patterns 310a and 310b, the design object element subjected to linear mapping may further change the shape of the design object element. However, for example, when the deformation pattern application areas 320a and 320b are large enough, the design object element changing unit 133 may further change the shape of the design object element by applying the deformation patterns 310a and 310b to the design object element according to the application method of the deformation patterns 310a and 310b after performing linear mapping on the design object element to change the shape of the design object element.

[0106] As described above, this embodiment illustrates the use of a genetic algorithm, one of the metaheuristic methods, as an algorithm for solving the optimization problem. Therefore, the design target element changing unit 133 selects a candidate solution for the optimization parameters for each design target element from the multiple candidate solutions for the optimization parameters calculated by the parameter acquisition unit 132. If there is only one design target element, the design target element changing unit 133 selects one candidate solution from the multiple candidate solutions for the optimization parameters calculated by the parameter acquisition unit 132. If there are multiple design target elements, the design target element changing unit 133 selects candidate solutions for the optimization parameters equal to the number of design target elements from the multiple candidate solutions for the optimization parameters calculated by the parameter acquisition unit 132, and sets one candidate solution for the optimization parameters for each design target element.

[0107] Then, the design object element changing unit 133 changes the shape of the design object element by applying the deformation patterns 310a and 310b to the design object element according to the type, application frequency, and application order of the deformation patterns 310a and 310b included in the candidate solutions of the optimization parameters selected as described above.

[0108] For example, the candidate solutions of the optimization parameters include information indicating the following: the type of the deformed patterns 310a and 310b indicates Figure 3A and Figure 3B The deformation patterns 310a and 310b shown in FIG. 3 are applied 5 times for the deformation pattern 310a and 2 times for the deformation pattern 310b. The order of application of the deformation patterns 310a and 310b is the order of application of the deformation patterns 310a and 310b. Figure 2B Such candidate solutions of optimization parameters are set for the design target element 230a of the basic shape shown.

[0109] In this case, the design object element changing unit 133 changes the shape of the basic shape design object element 230a by repeatedly applying the deformation pattern 310a five times and then repeatedly applying the deformation pattern 310b twice. Figure 3A and Figure 3B as well as Figure 4A and Figure 4B , as mentioned above.

[0110] Figures 5A to 5C This is a diagram conceptually showing an example of a process of designing an iron core when the shape of a design target element is changed. Figure 5A 230a and 230b are diagrams showing an example of an element of an iron core in which a basic shape of design target elements 230a and 230b is set. Figure 3B same. Figure 5B 1 is a diagram showing an example of an element of a core in which the basic-shaped design elements 230a and 230b are changed into changed design elements 240a and 240b by applying deformation patterns 310a and 310b to the basic-shaped design elements 230a and 230b. Figure 5C This is a diagram showing an example of an element of a core whose shape is further changed by performing linear mapping on the design target elements 240 a and 240 b after the change based on the deformation patterns 310 a and 310 b .

[0111] The design object element changing unit 133, for example, Figure 5AThe basic shapes of the design elements 230a and 230b shown are changed to Figure 5B The design target elements 240c and 240d after the change are shown.

[0112] like Figure 5B As shown, the design target elements 240c and 240d after being modified based on the deformed patterns 310a and 310b have changed not only their shapes but also their sizes relative to the design target elements 230a and 230b of the basic shape. Furthermore, when a displacement vector (having a magnitude greater than 0) is set for all coordinates of the deformed pattern application regions 320a and 320b, the positions of all outer edges of the design target elements 240c and 240d after being modified based on the deformed patterns 310a and 310b are shifted from the positions of the design target element regions 230a and 230b before the deformation.

[0113] In addition, for the convenience of explanation and expression, Figure 5A The basic shape of the design object elements 230a, 230b shown in FIG. Figure 5B The relationship between the design target elements 240c and 240d after the change shown does not correspond to the above-mentioned specific example (for the design target element 230a of the basic shape, the deformation pattern 310a is repeatedly applied five times and then the deformation pattern 310b is repeatedly applied twice).

[0114] When there are multiple design target elements, the design target element changing unit 133 changes the shape of each of the multiple design target elements as described above based on the optimization parameters set for the design target elements (the type, number of applications, and application order of the deformation patterns 310a and 310b).

[0115] Then, when the identification information set to the coordinates of the design target elements 240c and 240d after deformation based on the deformed patterns 310a and 310b is ID1, the design target element changing unit 133 changes the identification information ID1 to identification information ID3 for distinguishing the area of ​​the design target element from other areas. Figure 5A When comparing the design target elements 230a and 230b of the basic shapes shown, Figure 5B Partial regions of the design target elements 240c and 240d after the change are included in the core 210 before the change is made. Therefore, the identification information set for each coordinate of the region is changed from ID1 to ID3.

[0116] In addition, the design object element changing unit 133 changes the area of ​​the design object element before deformation based on the deformation patterns 310a and 310b (in Figures 5A to 5CIn the example shown, the identification information set for the coordinates of the area of ​​the basic-shaped design target elements 230a, 230b) that does not overlap with the deformed design target elements 240c, 240d based on the deformed patterns 310a, 310b is changed from ID3 to ID1. Figure 5A and Figure 5B In the example shown, there is no area for changing the identification information from ID3 to ID1. However, for example, Figure 5A The basic shape of the design object element 230a shown in FIG. Figure 5B In the case of an area where the deformed design target element 240 c does not overlap, the identification information set to each coordinate of the area is changed from ID3 to ID1.

[0117] Next, the design object element changing unit 133 performs linear mapping on the changed design object elements 240 c and 240 d based on the deformed patterns 310 a and 310 b calculated from the design object elements, based on the linear mapping parameters included in the candidate solutions of the optimization parameters set for the design object elements.

[0118] As described above, the parameters of the linear mapping include the values ​​of the components a to f shown in equation (1). The design target element changing unit 133 assigns the parameters of the linear mapping (the values ​​of the components a to f) included in the candidate solution of the optimization parameter to equation (1).

[0119] Then, the design object element changing unit 133 assigns the coordinates (x, y) of the outer edges of the design object elements 240c and 240d after deformation based on the deformation patterns 310a and 310b to formula (1), thereby calculating the coordinates (x', y') of the outer edge of the area of ​​the design object element after linear mapping is applied with respect to all the coordinates (x, y) of the outer edges of the deformed design object elements 240c and 240d.

[0120] When there are multiple design object elements, the design object element changing unit 133 performs the following operation on each of the multiple design object elements: assigning the parameters of the linear mapping (the values ​​of the components a to f) included in the optimization parameters set for the design object element to equation (1) to change the shape of the design object element.

[0121] The design object element changing unit 133, for example, Figure 5B The design elements 240c and 240d after the deformation are changed to Figure 5C In the following description, the regions 250a and 250b of the design object elements are referred to as linearly mapped design object elements 250a and 250b as needed.

[0122] like Figure 5C As shown, the linearly mapped design elements 250a and 250b have changed not only in shape but also in size relative to the modified design elements 240c and 240d based on the deformed patterns 310a and 310b. Furthermore, if a value other than 0 (zero) is set as the value of the component e or f, all positions of the outer edges of the linearly mapped design elements 250a and 250b are changed from those of the modified design elements 240c and 240d based on the deformed patterns 310a and 310b.

[0123] When there are multiple design target elements, the design target element changing unit 133 assigns the parameters of the linear mapping (the values ​​of the components a to f) included in the optimization parameters set for the design target element to equation (1), thereby performing the above-mentioned linear mapping on each of the multiple design target elements.

[0124] Then, when the identification information set to each coordinate of the linearly mapped design object elements 250a and 250b is ID1, the design object element changing unit 133 changes the identification information ID1 to identification information ID3 for distinguishing the area of ​​the design object element from other areas. Figure 5B When comparing the design elements 240c and 240d after the changes based on the deformed patterns 310a and 310b, Figure 5C Part of the region of the design target elements 250a and 250b after the linear mapping shown is included in the core 210 before the deformation is performed. Therefore, the identification information set for each coordinate of the region is changed from ID1 to ID3.

[0125] Furthermore, the design object element changing unit 133 changes the identification information set for the coordinates of the regions of the design object elements 240c and 240d after deformation based on the deformed patterns 310a and 310b that do not overlap with the design object elements 250a and 250b after linear mapping from ID3 to ID1. Figure 5B and Figure 5C In the example shown, there is no area for changing the identification information from ID3 to ID1. However, for example, Figure 5B The design object element 240c after deformation based on the deformation patterns 310a and 310b shown in FIG. Figure 5C In the case of an area where the design target elements 250a after the linear mapping shown do not overlap, the identification information set to each coordinate of the area is changed from ID3 to ID1.

[0126] Next, when there are design object elements that overlap or overflow in the design object elements 250a and 250b after the linear mapping calculated as above, the design object element changing unit 133 changes the design object elements again so as to eliminate the overlap and overflow in the design object elements. Here, overlap and overflow refer to at least one of overlap and overflow. Overlap means that at least a part of the area of ​​the design object element overlaps with the elements of the specified core. The elements of the specified core include the design object element. In addition, the elements of the specified core may also include elements other than the design object element (permanent magnet 220 in the example of this embodiment). The overlap is eliminated because, for example, if the overlap is not eliminated, multiple identification information is set for the overlapping part, so the identification information of the part cannot be uniquely determined. Overflow means that a part of the area of ​​the design object element overflows from the design area 200 (core 210). The overflow is eliminated, for example, to prevent a state in which a part of the area of ​​the design object element exists outside the design area 200 that is the design range of the design object element. In addition, for example, Figure 2A and Figure 2B As shown, when one of the four areas formed by dividing a cross section perpendicular to the center line of the IPMSM into four equal parts is set as the design area 200, if the portion where the overflow occurs is left as it is, the design object element finally determined will reach an area outside the one area (design area 200). This is also the purpose of eliminating the overflow. In addition, as described above, in this embodiment, an example is shown in which the shape of the changed design object elements 240a, 240b is further changed to the linearly mapped design object elements 250a, 250b by linear mapping the changed design object elements 240a, 240b based on the deformation patterns 310a, 310b. Therefore, in this embodiment, an example is shown in which the design object element changing unit 133 determines whether there are overlapping or overflowing design object elements in the linearly mapped design object elements 250a, 250b. However, for example, when linear mapping is not performed on the design target elements, the design target element changing unit 133 determines whether any design target elements overlap or overflow in the design target elements 240 c and 240 d after the change based on the deformed patterns 310 a and 310 b .

[0127] Figures 6A to 6D This is a diagram illustrating an example of overlapping.

[0128] Figure 6A This is a diagram conceptually showing an example of overlapping design target elements of the same type.

[0129] like Figure 6AAs shown in the left figure, when the design object elements 250c and 250d of the same type after linear mapping partially overlap each other, the design object element changing unit 133 Figure 6A As shown in the right figure of , an area surrounded by the outer edges of the linearly mapped design target elements 250c and 250d is set as one linearly mapped design target element 250e. In this case, the linearly mapped design target elements 250c and 250d are changed into one design target element.

[0130] Figure 6B This is a diagram conceptually showing an example of overlapping of different types of design target elements.

[0131] like Figure 6B As shown in the left figure of FIG, when the design object elements 250f and 250g after different types of linear mapping partially overlap each other, the design object element changing unit 133 Figure 6B As shown in the right figure of FIG, the overlapping areas are set as the design object elements 250f after the linear mapping with the highest priority. Figure 6B As shown in the right figure, the area obtained by removing the overlapping area from the linearly mapped design target element 250g with a lower priority is set as the new linearly mapped design target element 250h. The design target element changing unit 133 sets only the identification information ID3 for distinguishing the linearly mapped design target element 250f with the highest priority from other elements (areas) for each coordinate of the overlapping area, and deletes the other identification information ID3.

[0132] For example, when a permanent magnet is also a design element in addition to a flux barrier, the flux barrier and the permanent magnet are set as different identification information ID3. Figure 6B In the example shown, the region of the magnetic flux barrier becomes the linearly mapped design element 250h, and the region of the permanent magnet becomes the linearly mapped design element 250f. Therefore, the coordinates of the region where the linearly mapped design elements 250g and 250f overlap are assigned the identification information ID3 used to distinguish the permanent magnet from the other element (region), while the identification information ID3 used to distinguish the magnetic flux barrier from the other element (region) is eliminated. Furthermore, the priority order is pre-set based on the core design guidelines, the properties of the design element, and other factors.

[0133] Figure 6CThis diagram conceptually illustrates a first example of the overlap between linearly mapped design elements and predetermined core elements other than the design elements. These predetermined core elements are pre-set and have unchanged shapes. While the core shape is variable, the permanent magnet shape remains unchanged.

[0134] like Figure 6C As shown, when a portion of the linearly mapped design target element 250i overlaps with a portion of the predetermined core element (permanent magnet 220) other than the design target element without crossing the predetermined core element (permanent magnet 220) other than the design target element, the design target element changing unit 133 changes as shown in FIG. Figure 6C As shown in the right figure of FIG, the area obtained by removing the area overlapping with the predetermined core element (permanent magnet 220) other than the design target element from the linearly mapped design target element 250i is set as the new linearly mapped design target element 250j. In addition, the design target element changing unit 133 deletes the identification information ID3 for distinguishing the design target element from other elements (areas) set for each coordinate of the area overlapping with the predetermined core element (permanent magnet 220) other than the design target element.

[0135] Figure 6D This is a diagram conceptually showing a second example of the overlap between the design target element after linear mapping and elements of a predetermined core other than the design target element.

[0136] like Figure 6D As shown in FIG. 1 , when a portion of the linearly mapped design target element 250k overlaps with a portion of the predetermined core element (permanent magnet 220) other than the design target element across the predetermined core element (permanent magnet 220) other than the design target element, the design target element changing unit 133 changes as shown in FIG. Figure 6D As shown in the right figure of FIG, multiple regions obtained by excluding the regions overlapping with the predetermined core elements (permanent magnets 220) other than the design target elements from the linearly mapped design target element 250k are set as new linearly mapped design target elements 250m and 250l. In addition, the design target element changing unit 133 deletes the identification information ID3 set for each coordinate of the region overlapping with the predetermined core element (permanent magnets 220) other than the design target element, which is used to distinguish the design target element from other elements (regions).

[0137] Furthermore, to suppress an increase in the number of design target elements, the design target element changing unit 133 may select only one of the new linearly mapped design target elements 250m and 250l. For example, the design target element changing unit 133 may select the largest linearly mapped design target element 250l among the new linearly mapped design target elements 250m and 250l and eliminate the other linearly mapped design target elements 250m.

[0138] Figure 7 is a diagram illustrating an example of overflow.

[0139] like Figure 7 As shown in the left figure, when a part of the area of ​​the design object element 250n after linear mapping overflows from the design area 200 (iron core 210), the design object element changing unit 133 removes the area overflowing from the design area 200 from the design object element 250n after linear mapping and sets it as the new design object element 250o after linear mapping.

[0140] Regarding one of the design object elements after linear mapping, Figures 6A to 6D The overlap shown and Figure 7 In the case of overflow as shown, for example, the design element changing unit 133 may refer to Figures 6A to 6D As described above, the design object element after the linear mapping is changed, and as shown in FIG. Figure 7 As described above, the area of ​​the design target element after the change that exceeds the design area 200 is removed.

[0141] In this embodiment, as described above, the design target element changing unit 133 performs the following operations for each of the multiple candidate solutions for the optimization parameters calculated by the parameter acquiring unit 132: Each of the basic-shaped design target elements 230a and 230b included in the design region 200 (core) is changed to the linearly mapped design target elements 250a and 250b, respectively. This results in cores corresponding to the number of candidate solutions for the optimization parameters, each having different linearly mapped design target elements 250a and 250b.

[0142] <<Characteristic Value Calculation Unit 134>>

[0143] The characteristic value calculation unit 134 calculates a value representing the characteristic of a device when the device is operated, including an iron core whose shape of the design element has been changed by the design element changing unit 133. In this embodiment, the characteristic value calculation unit 134 performs numerical analysis to calculate a value representing the characteristic of the device when the device is operated, including the iron core having the linearly mapped design elements 250a and 250b calculated by the design element changing unit 133 as magnetic flux barriers.

[0144] Examples of device characteristics include the average torque of the rotor, core iron loss, and IPMSM efficiency. As such, the term "device characteristics" encompasses the characteristics of the components that make up the device. Therefore, in this embodiment, the characteristic value calculation unit 134 performs numerical analysis using the finite element method to calculate the magnetic flux density vector B generated in the core when the core, whose design target region has been modified, is excited, and the average torque of the rotor is calculated based on the calculated result as the device characteristic.

[0145] The characteristic value calculation unit 134 calculates the magnetic flux density vector B and the eddy current vector J in each micro region (mesh) using the finite element method based on Maxwell's equations according to the electromagnetic field analysis conditions including the excitation conditions. e In addition, as long as the magnetic flux density vector B and eddy current vector J in each micro area can be calculated e , it is also possible to use methods other than the finite element method (such as the difference method) for electromagnetic field analysis.

[0146] Used to calculate the magnetic flux density vector B and eddy current vector J e The basic equations of are generally given by the following equations (2) to (5).

[0147] [Formula 2]

[0148]

[0149] In equations (2) to (5), μ is the magnetic permeability [H / m]. A is the vector potential [T·m]. σ is the electrical conductivity [S / m]. J0 is the excitation current density [A / m 2 ]. is the scalar potential [V].

[0150] By combining equations (2) and (3) and solving them, we can calculate the vector potential A and the scalar potential Then, the magnetic flux density vector B and eddy current vector J are calculated according to equations (4) and (5): e .

[0151] The method of analyzing the electromagnetic field using the finite element method is a general method, and therefore, its detailed description is omitted here.

[0152] The characteristic value calculation unit 134 calculates the torque in each micro region based on the magnetic flux density vector B in each micro region, and calculates the average torque based on the calculated torque. Here, the torque F is calculated as Maxwell stress using the following equation (6), for example.

[0153] [Formula 3]

[0154]

[0155] In formula (6), n x 、n y are the unit vectors in the x-axis and y-axis directions, respectively. μ0 is the magnetic permeability of vacuum. ∫dΓ represents the line integral along the closed curve surrounding the object for which the electromagnetic force is to be calculated. In addition, B is the magnitude of the magnetic flux density vector. B x 、B y They are the x-axis component and y-axis component of the magnetic flux density vector respectively.

[0156] As described above, in this embodiment, the design target element changing unit 133 obtains cores corresponding to the number of candidate solutions for the optimization parameters as cores for different design target elements 250a and 250b after linear mapping. Therefore, in this embodiment, the characteristic value calculating unit 134 calculates the average rotor torque as an example of the characteristics of the device for each of the cores corresponding to the number of candidate solutions for the optimization parameters.

[0157] <<Determination Section 135>>

[0158] The determination unit 135 determines the shape of the core based on the value indicating the characteristics of the device calculated by the characteristic value calculation unit 134 .

[0159] For example, if the value representing the device characteristic calculated by the characteristic value calculation unit 134 satisfies a predetermined condition, the determination unit 135 determines the candidate solution for the optimization parameters used when calculating the design target elements (in this embodiment, the linearly mapped design target elements 250a and 250b) included in the core as the optimal solution. The core exhibits the value that best represents the characteristic among the values ​​that satisfy the predetermined condition. If the device characteristic is the average torque of the rotor, the predetermined condition is, for example, that the average torque of the rotor is greater than a predetermined value. The predetermined value is determined based on, for example, the value required by the IPMSM of the design target.

[0160] As described above, this embodiment illustrates a case where the core shape determination unit 130 uses a genetic algorithm to calculate the optimal solution for the optimization parameters. Therefore, if the values ​​representing the device characteristics calculated by the characteristic value calculation unit 134 do not satisfy the specified conditions, the parameter acquisition unit 132 updates the candidate solutions for the already calculated optimization parameters using the genetic algorithm. The processes described above by the design element modification unit 133, characteristic value calculation unit 134, and determination unit 135 are then repeated using the updated candidate solutions for the optimization parameters.

[0161] Furthermore, even if the number of repetitive processes in the parameter acquisition unit 132, design element change unit 133, characteristic value calculation unit 134, and determination unit 135 described above exceeds a predetermined value, there may be cases where none of the values ​​representing the device characteristics calculated by the characteristic value calculation unit 134 satisfy the predetermined conditions. In such cases, the determination unit 135 determines as the optimal solution, for example, the candidate solution for the optimization parameters used when calculating the design element of the core having the best characteristic (in this embodiment, the maximum value of the average torque of the rotor) among the values ​​representing the device characteristics calculated by the characteristic value calculation unit 134. The predetermined value is a value generally used in genetic algorithms.

[0162] <Output Unit 140>

[0163] The output unit 140 outputs information about the candidate solutions of the optimization parameters determined by the determination unit 135. For example, the output unit 140 outputs information that uniquely identifies the position, shape, and size of the design target element (in this embodiment, the linearly mapped design target elements 250a and 250b) calculated by changing the basic shape of the design target element 230 according to the optimal solution of the optimization parameters determined by the determination unit 135. For example, Figure 5C The linearly mapped design object elements 250a and 250b shown are design object elements calculated by changing the basic shape of the design object element 230 according to the optimal solution of the optimization parameter. In this case, the output unit 140 may also display Figure 5C The image shown represents the core 210, the permanent magnet 220, and the linearly mapped design elements 250a and 250b. Output methods include, for example, display on a computer monitor, storage on a storage medium internal to or external to the core design device 100, and transmission to an external device. The position of the design element may be information that uniquely identifies the position of the design element; for example, the position of the center of gravity of the design element may be used. Alternatively, a coordinate group representing the outline of the design element may be information that uniquely identifies the position, shape, and size of the design element.

[0164] The core is manufactured based on the information output by the output unit 140. The design after the core design device 100 calculates the optimal solution for the optimization parameters can be performed by a designer. A portion of the design after the core design device 100 calculates the optimal solution for the optimization parameters can also be performed by the core design device 100. The core design is completed by creating a design drawing of the core. The core design elements in the design drawing can be identical to the optimal solution for the optimization parameters. Furthermore, the core design elements in the design drawing may not be strictly identical to the optimal solution for the optimization parameters. For example, the shape of some or all of the design elements indicated by the optimal solution for the optimization parameters can be simplified. That is, the final position, shape, and size of the design elements can be determined based on the optimal solution for the optimization parameters. The core is manufactured according to the design drawing. The core design elements in the manufactured core are those based on the optimal solution for the optimization parameters. For example, the number of design elements in the manufactured core is identical to the number of design elements indicated by the optimal solution for the optimization parameters. Furthermore, for example, the design elements in the manufactured core are located in a region that includes the center of gravity of the design elements indicated by the optimal solution for the optimization parameters. In addition, the shape of the design object element of the manufactured iron core is the same as the shape of the design object element shown by the optimal solution of the optimization parameters. However, the design object element of the manufactured iron core may not be strictly the same as the optimal solution of the optimization parameters. For example, the shape of the design object element of the manufactured iron core may be a shape that simplifies part or all of the shape of the design object element shown by the optimal solution of the optimization parameters. In this case, in a cross section cut perpendicularly to the center line of the iron core, the direction in which the straight line connecting the center line of the iron core and the center of gravity position of the design object element extends may also be the same in the design object element of the manufactured iron core and the design object element shown by the optimal solution of the optimization parameters. In addition, the aspect ratio of the design object element of the manufactured iron core may also be the same as the aspect ratio of the design object element shown by the optimal solution of the optimization parameters. That is, the iron core (design object element) can be manufactured based on the optimal solution of the optimization parameters. The position, shape and size of the design object element can be determined by the design drawing, and the manufacture of the iron core itself is carried out, for example, using known technology.

[0165] [flow chart]

[0166] Next, refer to Figure 8A and Figure 8B An example of the core design method is described below. The core design method is described below by taking the case where the core design device 100 executes the core design method as an example.

[0167] First, in step S801, the design source information acquisition unit 110 acquires information about the core of the design target. In this embodiment, the design source information acquisition unit 110 acquires information about the design area 200, which is the design target area, information about the core elements (permanent magnets 220) other than the design target elements, and information about the physical property values ​​of each core element. Then, the design source information acquisition unit 110 sets the design area 200 in the main storage device (work area) and sets the core elements (permanent magnets 220) other than the design target elements in the design area 200. In addition, the design source information acquisition unit 110 sets identification information ID1 for each coordinate of the design area 200 and sets identification information ID2 for each coordinate of the core elements (permanent magnets 220) other than the design target elements.

[0168] Next, in step S802, the basic shape acquisition unit 120 acquires information of the basic shape design target elements 230a and 230b and sets it in the design area 200. Then, the basic shape acquisition unit 120 changes the identification information ID1 set for each coordinate of the basic shape design target elements 230a and 230b to identification information ID3.

[0169] Next, in step S803, the deformed pattern acquisition unit 131 acquires information about the deformed patterns 310a and 310b. In this embodiment, the deformed pattern information 310a and 310b includes information indicating the displacement vectors at the coordinates of the deformed pattern application areas 320a and 320b. Furthermore, the deformed pattern acquisition unit 131 acquires information about multiple types of deformed patterns 310a and 310b.

[0170] Next, in step S804, the parameter acquisition unit 132 calculates candidate solutions for the optimization parameters (application parameters). In this embodiment, an example is shown in which one candidate solution for the optimization parameters includes the type of deformation patterns 310a, 310b, the application parameters and the order of application, and the parameters of the linear mapping. Furthermore, in this embodiment, an example is shown in which, in the first step S804 process, the parameter acquisition unit 132 calculates initial values ​​for multiple candidate solutions as the initial values ​​for the candidate solutions for the optimization parameters using a known method using a genetic algorithm. Furthermore, in this embodiment, an example is shown in which, in subsequent steps of step S804, the parameter acquisition unit 132 updates the already calculated candidate solutions for the optimization parameters using a genetic algorithm.

[0171] Next, in step S805 , the design target element changing unit 133 selects one candidate solution for an optimization parameter for one design target element from among the plurality of candidate solutions for the optimization parameter calculated in step S804 .

[0172] Next, in step S806, the design object element changing unit 133 applies the deformed patterns 310a and 310b to the design object element according to the type, number of applications, and application order of the deformed patterns 310a and 310b included in the candidate solution of the optimization parameter selected in step S805, thereby changing the shape of the design object element. By changing the shape of the design object element in this way, the design object element changing unit 133 calculates the design object element 240 after deformation based on the deformed pattern 310 (see FIG. 4 and FIG. 5 ). Figure 5B ).

[0173] Next, in step S807, the design object element changing unit 133 performs linear mapping on the design object elements 240c and 240d after deformation based on the deformation patterns 310a and 310b, based on the parameters of the linear mapping among the application parameters included in the candidate solutions of the optimization parameters set for the design object elements, thereby calculating the linearly mapped design object elements 250a and 250b (see Figure 5C ).

[0174] Next, in step S808, the design object element changing unit 133 determines whether there are any overlapping or overflowing design object elements in the linearly mapped design object elements 250a and 250b. If the result of this determination is that there are no overlapping or overflowing design object elements 250a and 250b in the linearly mapped design object elements 250a and 250b (No in step S808), the processing of step S809 is omitted and the following process is performed. Figure 8B On the other hand, if there is at least one linearly mapped design object element 250a or 250b that overlaps or overflows (if yes in step S808), the process of step S809 is performed.

[0175] In step S809, the design object element changing unit 133 changes the linearly mapped design object elements 250a and 250b again so as to eliminate the overlap and overflow in the linearly mapped design object elements 250a and 250b (see Figures 6A to 6D as well as Figure 7 ).

[0176] Next, in step S810, the characteristic value calculation unit 134 calculates a value representing the characteristic of the device when operating the device having an iron core equipped with the linearly mapped design elements 250a and 250b calculated in steps S807 and S808 as flux barriers. In this embodiment, the characteristic value calculation unit 134 calculates the average torque of the rotor as the device characteristic.

[0177] Next, in step S811, the decision unit 135 determines whether all candidate solutions for the optimization parameters calculated in step S804 have been selected. If the number of design target elements is one, the decision unit 135 determines whether all candidate solutions for the optimization parameters calculated in step S804 have been selected in step S811. If the number of design target elements is multiple, the decision unit 135 determines, for example, in step S811 whether all possible combinations of candidate solutions for the number of design target elements have been selected from the multiple candidate solutions for the optimization parameters calculated in step S804.

[0178] If the result of this determination indicates that none of the candidate solutions for the optimization parameters calculated in step S804 have been selected (No in step S811), step S805 is performed again. Then, in step S805, the unselected candidate solutions are selected. Then, in steps S805 to S809, the linearly mapped design elements 250a and 250b are calculated based on the unselected candidate solutions. Then, in step S810, a value representing the characteristics of the device when operating the core having the linearly mapped design elements 250a and 250b as flux barriers is calculated.

[0179] As described above, if it is determined in step S811 that all candidate solutions for the optimization parameters calculated in step S804 have been selected (if "Yes" in step S811), the process proceeds to step S812. In step S812, the decision unit 135 determines whether any of the values ​​representing the characteristics of the device calculated in step S810 satisfy a predetermined condition. In this embodiment, the predetermined condition is exemplified by the condition that the average torque of the rotor is greater than or equal to a predetermined value.

[0180] As a result of this determination, if the values ​​representing the device characteristics calculated in step S810 contain a value that satisfies the specified conditions (if "Yes" in step S812), the process proceeds to step S813. In step S813, the decision unit 135 determines as the optimal solution the candidate solution for the optimization parameters used when calculating the linearly mapped design elements 250a and 250b of the core having the best characteristics among the values ​​representing the device characteristics that satisfy the specified conditions. In this embodiment, the decision unit 135 determines as the optimal solution the candidate solution for the optimization parameters used when calculating the linearly mapped design elements 250a and 250b of the core having the maximum value of the average torque of the rotor. The process of step S816, described below, is then executed.

[0181] If the result of the judgment in step S812 is that there is no value that satisfies the prescribed conditions among the values ​​representing the characteristics of the device calculated in step S810 (if no in step S812), the process of step S814 is performed. In step S814, the decision unit 135 determines whether the number of times the process of steps S804 to S812 is repeated exceeds a prescribed value. The prescribed value is, for example, a value generally used in a genetic algorithm. As a result of this judgment, if the number of repetitions does not exceed the prescribed value (if no in step S814), the process of step S804 is performed again. The process of step S804 performed in this way becomes the process of step S804 after the second time. As described above, in the process of step S804 after the second time, the parameter acquisition unit 132 updates the candidate solution of the optimization parameter that has been calculated according to the genetic algorithm. The process of the above-mentioned steps S805 to S812 is performed again using the candidate solution of the optimization parameter after being updated in this way.

[0182] If the result of step S814 indicates that the number of repetitions of steps S804 to S812 exceeds the specified value (if "Yes" in step S814), the process proceeds to step S815. In step S815, the decision unit 135 determines the candidate solution for the optimization parameters used when calculating the linearly mapped design elements 250a and 250b of the core, which exhibits the best characteristic among the values ​​of the device characteristics calculated in the previous repetitions of steps S804 to S812, as the optimal solution. The process then proceeds to step S816.

[0183] In step S816, the output unit 140 outputs information about the candidate solution of the optimization parameter determined in step S813 or S815. When the processing of step S816 is completed, Figure 8A and Figure 8B The processing of the flowchart ends.

[0184] [Hardware of the Core Design Device 100]

[0185] Next, an example of the hardware of the core design device 100 is described. Figure 9 In FIG. 1 , the core design device 100 includes a CPU 901 , a main storage device 902 , an auxiliary storage device 903 , a communication circuit 904 , a signal processing circuit 905 , an image processing circuit 906 , an I / F circuit 907 , a user interface 908 , a display 909 , and a bus 910 .

[0186] The CPU 901 controls the entire core design device 100. The CPU 901 uses the main storage device 902 as a work area and executes programs stored in the auxiliary storage device 903. The main storage device 902 temporarily stores data. The auxiliary storage device 903 stores various data in addition to the programs executed by the CPU 901.

[0187] The communication circuit 904 is a circuit for communicating with the outside of the core design device 100. The communication circuit 904 can communicate with the outside of the core design device 100 either wirelessly or by wire.

[0188] The signal processing circuit 905 performs various signal processing on the signal received by the communication circuit 904 and the signal input under the control of the CPU 901 .

[0189] The image processing circuit 906 performs various image processing on the signal input under the control of the CPU 901. The signal subjected to the image processing is output to the display 909, for example.

[0190] The user interface 908 is a portion for the operator OP to instruct the core design device 100. The user interface 908 includes, for example, buttons, switches, and dials. Alternatively, the user interface 908 may include a graphical user interface using the display 909.

[0191] The display 909 displays an image based on the signal output from the image processing circuit 906. The I / F circuit 907 exchanges data between devices connected to the I / F circuit 907. Figure 9 In the figure, user interface 908 and display 909 are shown as devices connected to I / F circuit 907. However, the devices connected to I / F circuit 907 are not limited to these. For example, I / F circuit 907 may be connected to a portable storage medium. In addition, at least a portion of user interface 908 and display 909 may be located outside of core design device 100.

[0192] Furthermore, the CPU 901, the main storage device 902, the auxiliary storage device 903, the signal processing circuit 905, the image processing circuit 906, and the I / F circuit 907 are connected to a bus 910. Communication between these components is performed via the bus 910. In addition, the hardware of the core design device 100 is not limited to the hardware as long as it can realize the functions of the core design device 100 described above. Figure 9 For example, a GPU may be used as a processor in addition to or instead of the CPU 901 .

[0193] [Calculation example]

[0194] Next, a calculation example will be described. Figures 10A to 10C It is a figure which shows the iron core before design and the iron core after design.

[0195] FIG10 shows the original shape of the core. In this calculation example, the method described in Patent Document 1 and the method described in this embodiment are used to calculate the original shape of the core. Figure 10A The core shown has additional flux barriers.

[0196] As such, the calculation object element in this calculation example is the flux barrier. Figures 10A to 10C In the figure, the flux barrier area is the white area outside the circle. The core area and the permanent magnet area are gray areas with different concentrations (the permanent magnet area is a rectangle). Figures 10A to 10C The six circular white areas shown are predetermined core elements other than the design target elements (elements whose shapes do not change).

[0197] In this calculation example, Figure 10A The area surrounded by the outer edge of the core area ( Figure 10A The area of ​​the annular sector with a central angle of 180° is set as the design area. Then, in the area within the design area and in the area on the outer circumference side of the permanent magnet, 8 circular areas are set as the basic shape of the design object element, that is, the flux barrier. In addition, Figures 10A to 10C The basic shape of the flux barrier is not shown in FIG. That is, as described above, Figures 10A to 10C The six circular white areas shown are predetermined core elements other than the design target elements (elements whose shapes do not change), and are different from the basic shape of the flux barrier.

[0198] In this calculation example, the average torque when the core is excited with an excitation current of 25A at an advance angle of 20° is used as the device characteristic. A genetic algorithm is used to search for the shape of the design element that maximizes the average torque. Figure 10B A comparative example is shown. Figure 10B The comparative example of JP-A-2004-11969 shows the result of performing only linear mapping on a design target element of a basic shape as described in Patent Document 1. Figure 10C Invention examples are shown. Figure 10C The invention example shows the results of performing changes based on deformed patterns 310a and 310b, as described in this embodiment, and linear mapping of the design target elements after the deformation based on deformed patterns 310a and 310b. In this invention example, deformed patterns 310a and 310b are used as deformed pattern application areas 320a and 320b, each having a square area with a side length four times the diameter of the basic circle.

[0199] In will use Figure 10AWhen the average torque of the rotor is set to 100, the Figure 10B The average torque of the rotor when using the iron core of the comparative example shown is 109.4 (the average torque value described in this calculation example is a dimensionless value). Figure 10C The average torque of the rotor in the case of the iron core of the invention example shown is 111.4. As shown above, it can be seen that the method of this embodiment (invention example) can improve the average torque of the rotor compared to the method (comparative example) described in Patent Document 1. Figure 10B The front end regions 1010a and 1010b of the flux barrier of the comparative example shown in FIG10 and the front end regions 1010c and 1010d of the flux barrier of the invention example shown in FIG10C show that the flux barrier of the invention example has a shape in which the front end region is narrower than that of the comparative example. This is considered to be one of the reasons why the method of this embodiment (inventive example) improves the average torque of the rotor compared to the method (comparative example) described in Patent Document 1. In addition, as Figure 10C As shown, in the method of this embodiment (invention example), even if nonlinear mapping is performed on the basic shape of the design object element (flux barrier), the flux barrier obtained as the optimal solution is solidified to a certain extent, which can prevent the flux barrier from becoming an extremely complex shape.

[0200] [Summarize]

[0201] As described above, in this embodiment, the core design device 100 obtains a design element 230 having a basic shape, deformation patterns 310a and 310b, and application parameters. The deformation patterns 310a and 310b represent the deformation of the design element's shape and indicate the displacement of each position in the relative coordinate system relative to the basic shape of the design element. Furthermore, at least one deformation pattern 310a and 310b represents the deformation so that the shapes before and after the change are in phase. The application parameters include parameters indicating the method for applying the deformation patterns 310a and 310b to the design elements 230a and 230b. The core design device 100 applies the deformation patterns 310a and 310b to the design element according to the method for applying the deformation patterns 310a and 310b included in the application parameters, thereby performing nonlinear mapping on the design element 230 and changing the shapes of the design elements 230a and 230b. The core design device 100 then calculates values ​​representing the characteristics of the device when the device is operated with the core having the modified shapes of the design elements 230a and 230b, and determines the core shape based on the calculated values. This allows the search for a core shape that improves device performance to be performed within a wider range within the achievable range.

[0202] In addition, in this embodiment, all deformation patterns 310a and 310b show deformation contents in which the shapes before and after the change are in an in-phase mapping relationship. Therefore, the in-phase property of the design object element before and after the deformation can be reliably preserved.

[0203] In this embodiment, the method for applying deformation patterns 310a and 310b includes the number of times the deformation patterns 310a and 310b are applied to the design element. Furthermore, the method for applying deformation patterns 310a and 310b includes the order in which the multiple deformation patterns 310a and 310b are applied to the design element. This allows the homogeneity of the design element before and after deformation to be preserved, and allows the search for a design element shape that improves device characteristics to be conducted across a wide search area.

[0204] Furthermore, in this embodiment, the application parameters also include linear mapping parameters, which are used to apply linear mapping to the design element. The core design device 100 performs the following operations: applying deformation patterns 310a and 310b to the design element according to the application method of deformation patterns 310a and 310b to change the shape of the design element; and applying linear mapping to the design element. Therefore, (assuming the same computation time) it is possible to search for a core shape that improves device performance across a wider search area.

[0205] Furthermore, in this embodiment, the core design device 100 uses application parameters as optimization parameters and calculates the optimal solution for the optimization parameters using an optimization algorithm. Therefore, for example, the designer does not need to determine the application parameters through trial and error, which can reduce the designer's burden.

[0206] In addition, in this embodiment, the core design device 100 uses a metaheuristic method to determine the optimal solution for the optimization parameters. Therefore, it is possible to prevent the optimal solution from being calculated as a local solution and to easily obtain a novel shape for the core.

[0207] [Modification]

[0208] <First Modification>

[0209] In this embodiment, the case where the design area 200 is an area surrounded by the outer edge of the core 210 is exemplified. Figure 10C As shown, the flux barrier may reach the outer periphery of the core. In a rotor, if the flux barrier reaches the outer periphery of the core, the centrifugal force exerted on the rotor by its rotation could damage the rotor. Therefore, the design area can be defined as the area excluding the ends of core 210 and the area near them. This prevents the design of a core that does not meet the equipment specifications without complex calculations.

[0210] Alternatively, instead of or in addition to setting the design region in this manner, the following method may be employed. Specifically, the core shape determination unit 130 solves a forward problem that links electromagnetic field analysis and stress analysis, calculating the magnetic flux density vector and stress vector in each microregion, thereby analyzing the stress generated in the core by the centrifugal force exerted on the rotor as the rotor rotates. The core shape determination unit 130 then searches for the optimal solution for the optimization parameters based on both the device characteristics based on the magnetic flux density vector and the device characteristics based on the stress vector.

[0211] For example, the core shape determination unit 130 uses the finite element method to calculate the stress vector applied to each microregion (mesh) of the core according to the stress conditions. The finite element method is a general method for analyzing stress. Furthermore, if the stress vector in each microregion (mesh) can be calculated through numerical analysis, methods other than the finite element method (such as the difference method) may be used as a method for calculating the stress vector.

[0212] The electromagnetic field analysis described in this embodiment (magnetic flux density vector B and eddy current vector J in each micro region) e When the micro area used in the calculation) is different from the micro area used in the stress analysis, the core shape determination unit 130 calculates the stress vector in the micro area used in the electromagnetic field analysis, for example, by interpolating the stress vectors of each micro area used in the stress analysis.

[0213] In the electromagnetic field analysis (magnetic flux density vector B and eddy current vector J in each small area e In the calculation of the stress vector, a BH curve corresponding to the stress vector in the micro region used in the electromagnetic field analysis is used as the BH curve.

[0214] For example, the value of the characteristic of the device determined based on the results of the electromagnetic field analysis is set to V1. In addition, the weight coefficient for the characteristic of the device determined based on the results of the electromagnetic field analysis is set to W1 (>0). In addition, the value of the characteristic of the device determined based on the results of the stress analysis is set to V2. In addition, the weight coefficient for the characteristic of the device determined based on the results of the stress analysis is set to W2 (>0). In this case, the core shape determination unit 130 searches for a mapping that maximizes or minimizes the value of W1×V1+W2×V2. In addition, when a larger value of the characteristic of the device determined based on the results of the electromagnetic field analysis indicates better characteristics, and a smaller value of the weight coefficient for the characteristic of the device determined based on the results of the stress analysis indicates better characteristics, the core shape determination unit 130 (determination unit 135) can simply search for, for example, an optimization parameter that minimizes -W1×V1+W2×V2.

[0215] The direct problem of linking electromagnetic field analysis and stress analysis can be achieved using the known method described in Patent Document 1, for example. Therefore, a detailed description of this method is omitted here. Furthermore, depending on the characteristics of the device considered when designing the core, it is possible to perform stress analysis alone without performing electromagnetic field analysis.

[0216] <Second Modification>

[0217] In this embodiment, a case where a genetic algorithm is used as an algorithm for an optimization problem is exemplified. However, the algorithm for the optimization problem is not limited to the genetic algorithm. A metaheuristic method other than the genetic algorithm may also be used. If a metaheuristic method is used, it is possible to suppress the optimal solution from being calculated as a local solution, and it is easy to obtain a new shape, so it is preferred. However, an algorithm for the optimization problem other than a metaheuristic method such as a gradient method may also be used. In addition, if the optimal solution problem is solved by using an application parameter as an optimization parameter, it is possible to design an iron core that shows a better value as a value representing the characteristics of the device, so it is preferred. However, it is not necessarily necessary to use the application parameter as an optimization parameter to solve the optimal solution problem. For example, the designer may also make the application parameter different by trial and error, and search for an application parameter whose value representing the characteristics of the device satisfies a prescribed condition (for example, the value representing the characteristics of the device is a better value than a prescribed value).

[0218] <Third Modification>

[0219] In this embodiment, the case of designing the shape of the rotor of the IPMSM is exemplified. However, the core to be designed is not limited to the core of the rotor of the IPMSM. For example, the core of the rotor of a cage induction motor may be used as the core to be designed. In this case, the conductor rod embedded in the core constituting the core may be used as the design object element. In addition, the core of the stator may be used as the core to be designed. In this case, for example, the space of the recess formed on the front end surface (the surface opposite to the core of the rotor) of the teeth of the core constituting the stator may be used as the design object element. In addition, the core of the rotor or the core of the stator of a generator as a rotating electrical machine other than a motor may be used as the core to be designed. In addition, the core of the transformer may be used as the core to be designed.

[0220] <Fourth Modification>

[0221] In this embodiment, the case where all the deformation patterns 310a and 310b represent deformation contents such that the shapes before and after the change are in phase mapping is illustrated. In this way, the phase relationship of the design object element before and after the deformation can be preserved. Therefore, each time the shape of the design object element is changed, the shapes before and after the change can be made in phase mapping. This is preferable because the shape of the design object element can be changed within the range that can be achieved as much as possible. However, as long as at least one of the deformation patterns 310a and 310b represents deformation contents such that the shapes before and after the change are in phase mapping, the deformation patterns 310a and 310b may also include deformation patterns that do not represent deformation contents such that the shapes before and after the change are in phase mapping. In such a case, for example, it can also be as follows. First, the core design device 100 determines whether the basic shape of the design object element and the final shape of the design object element are in phase mapping. Then, if the basic shape of the design element and the final shape of the design element do not form an in-phase relationship, the core design device 100 changes the application method of the deformation patterns 310a and 310b (for example, changing at least one of the content, number, and application order of the deformation patterns 310a and 310b) and searches again for the optimal solution for the shape of the design element. Alternatively, the core design device 100 may display information about the final shape of the design element on a display device to prompt the designer. In this case, if the final shape of the design element is not achievable, the designer may instruct the core design device 100 to search again for the optimal solution for the shape of the design element. Furthermore, even if the design element before and after deformation does not form an in-phase relationship, if the final shape of the design element is achievable, the designer may adopt that shape. In this way, the design element before and after deformation does not need to maintain in-phase. Furthermore, if, for example, the unachievable shape clearly has a low impact on the characteristics of the device, the designer may change the final shape of the design element.

[0222] <Other Modifications>

[0223] Furthermore, the core design device and core design method described in the above-described embodiments of the present invention can be implemented by executing a program on a computer. Furthermore, a computer-readable storage medium storing the program and a computer program product such as the program can also be applied as embodiments of the present invention. Furthermore, a computer-readable storage medium refers to a non-transitory storage medium. Examples of storage media include floppy disks, hard disks, optical disks, magneto-optical disks, CD-ROMs, magnetic tapes, non-volatile memory cards, and ROMs.

[0224] In addition, the embodiments of the present invention described above are merely examples of specific implementations of the present invention and are not intended to limit the technical scope of the present invention. That is, the present invention can be implemented in various forms without departing from its technical concept or its main features.

[0225] Industrial Availability

[0226] The present invention can be used, for example, in designing a device including an iron core.

Claims

1. An iron core design device for performing calculations related to the design of an iron core shape, comprising: a basic shape acquiring unit configured to acquire a basic shape of a design target element of the core; as well as a core shape determining unit that determines the shape of the core by changing the shape of a design target element of the core from the basic shape; The core shape determining unit includes: a deformation pattern acquisition unit that acquires a deformation pattern representing a deformation of a shape of the design target element; a parameter acquisition unit for acquiring application parameters; a design object element changing unit that changes the shape of the design object element using the deformation pattern and the application parameter; a characteristic value calculation unit that calculates a value indicating a characteristic of the device when the device having the core in which the shape of the design element is changed is operated; as well as a determination unit that determines the shape of the core based on a value representing a characteristic of the device, The application parameters include parameters indicating a method of applying the deformed pattern when applying the deformed pattern to the design target element. The design object element changing unit applies the deformation pattern to the design object element according to the application method to perform nonlinear mapping on the design object element. The deformation pattern represents the displacement of each position in the relative coordinate system on the basic shape of the design object element. At least one of the deformation patterns indicates deformation content in which the shapes before and after the change are in an in-phase mapping relationship.

2. The core design device according to claim 1, All of the deformation patterns indicate deformation contents in which the shapes before and after the change are in an in-phase mapping relationship.

3. The core design device according to claim 1 or 2, The method of applying the deformation pattern includes at least one of the number of times the deformation pattern is applied to the design target element and the order in which the plurality of deformation patterns are applied to the design target element.

4. The core design device according to claim 1 or 2, The application parameters also include linear mapping parameters, which are parameters used to implement linear mapping on the design object elements. The design object element changing unit further performs linear mapping on the design object element.

5. The core design device according to claim 1 or 2, The core shape determination unit uses the application parameters as optimization parameters and calculates an optimal solution for the optimization parameters using an optimization algorithm.

6. The core design device according to claim 5, The algorithm for the optimization problem is a meta-heuristic algorithm, The parameter acquisition unit calculates candidate solutions for the optimization parameters. The core shape determination unit determines a candidate solution for the optimization parameter when a value representing a characteristic of the device satisfies a predetermined condition as an optimal solution for the optimization parameter.

7. The core design device according to claim 1 or 2, The design target element includes at least one of a flux barrier and a permanent magnet in a rotor of a rotating electrical machine.

8. A core design method, wherein a computer performs calculations related to the design of the core shape. The computer executes: a basic shape obtaining step of obtaining a basic shape of a design target element of the iron core; as well as a core shape determination step of determining the shape of the core by changing the shape of a design target element of the core from the basic shape; The core shape determination process includes: a deformation pattern acquisition step of acquiring a deformation pattern indicating the deformation of the shape of the design object element; a parameter acquisition process for acquiring application parameters; a design object element changing step of changing the shape of the design object element using the deformation pattern and the application parameter; a characteristic value calculation step of calculating a value indicating a characteristic of the device when the device including the core having the changed shape of the design target element is operated; as well as a step of determining the shape of the core based on a value representing a characteristic of the device, The application parameters include parameters indicating a method of applying the deformed pattern when applying the deformed pattern to the design target element. The design object element changing step applies the deformation pattern to the design object element according to the application method to perform nonlinear mapping on the design object element. The deformation pattern represents the displacement of each position in the relative coordinate system on the basic shape of the design object element. At least one of the deformation patterns indicates deformation content in which the shapes before and after the change are in an in-phase mapping relationship.

9. A computer program product comprising a computer program, wherein when the computer program is executed by a processor, the computer program implements the steps of the core design method according to claim 8.

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