Evaluation device and evaluation method

Abstract

An evaluation device (100) evaluates the vibration of a magnetic material. The evaluation device (100) is provided with a magnetic core (10), a plurality of winding parts (20), and first measurement devices (31, 32, 33). The magnetic core (10) is made of a magnetic material. The magnetic core (10) includes a leg part (11). The winding parts (20) are arranged with a gap (G) in the axial direction of the leg part (11), and are attached to the leg part (11) in such a manner that the leg part (11) is exposed from the gap (G). The winding parts (20) are constructed to excite the magnetic core (10) by energization. The first measurement devices (31, 32, 33) measure the vibration of the leg part (11).

Description

Technical Field

[0001] The present disclosure relates to an evaluation apparatus and an evaluation method for evaluating vibrations of magnetic materials.

Background Art

[0002] It is known that when a magnetic material is magnetized, a phenomenon called magnetostriction occurs in which the dimensions of the magnetic material change according to the strength of the magnetic field. For example, in devices such as transformers, an alternating magnetic field is generated in a magnetic core made of a magnetic material when an alternating current flows through an excitation coil, so the magnetostriction (expansion and contraction) occurring in the magnetic core also fluctuates periodically. Such a magnetostriction phenomenon can be a cause of vibration of the magnetic core. When the magnetic core vibrates, there is a possibility that vibration and noise will occur in the device on which the magnetic core is mounted. By evaluating the vibration of the magnetic material constituting the magnetic core, a device with reduced noise can be proposed.

[0003] For example, Non-Patent Document 1 discloses measuring the vibration of a magnetic core in order to analyze the influence of a magnetic material on the noise of a transformer. In Non-Patent Document 1, for a model transformer having a three-phase three-leg magnetic core, the vibration of the yoke of the magnetic core and the joint between the yoke and the leg is measured by a laser Doppler vibrometer.

[0004] Patent Document 1 also discloses measuring the vibration of a magnetic material by a laser Doppler vibrometer. In Patent Document 1, for example, the displacement of a magnetic material is measured by irradiating a reflective object on the magnetic material with laser light from a laser Doppler vibrometer. The reflective object is arranged at a position adjacent to the winding portion on the magnetic material.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Non-Patent Documents

[0006] [Non-Patent Document 1] Seiji Okabe, et al., "Transformer Characteristic Analysis Technology of JFE Steel," JFE Technical Report, JFE Steel Corporation, August 2015, No. 36, pp. 17-23. [Overview of the project] [Problems that the invention aims to solve]

[0007] Non-patent document 1 and patent document 1 measure the vibration of the magnetic core outside the winding section. In each document, vibration measurements are not performed at the base of the magnetic core, i.e., the part where the winding section is attached. However, it is presumed that particularly large vibrations can occur at the base due to magnetization by the winding section, for example, and the interaction between the current flowing through the winding section and the magnetic field generated at the base. Therefore, if it is possible to measure the vibration of the base, it is thought that it will be easier to propose equipment with reduced noise.

[0008] The object of this disclosure is to provide an evaluation device capable of measuring the vibration of a leg to which a winding section is attached. [Means for solving the problem]

[0009] The evaluation device according to this disclosure evaluates the vibration of a magnetic material. The evaluation device comprises a magnetic core, a plurality of winding sections, and a first measuring device. The magnetic core is made of a magnetic material. The magnetic core includes legs. The winding sections are arranged with gaps in the axial direction of the legs and are mounted on the legs so that the legs are exposed through the gaps. The winding sections are configured to excite the magnetic core by energizing it. The first measuring device measures the vibration of the legs. [Effects of the Invention]

[0010] According to the evaluation device described herein, it is possible to measure the vibration of the leg portion to which the winding portion is attached. [Brief explanation of the drawing]

[0011] [Figure 1] Figure 1 is a plan view showing the main configuration of the evaluation apparatus according to the embodiment. [Figure 2] Figure 2 is a side view of the evaluation apparatus shown in Figure 1. [Figure 3] Figure 3 is an exploded perspective view showing the configuration of the magnetic core, winding section, and support frame included in the evaluation device shown in Figures 1 and 2. [Figure 4] Figure 4 is a flowchart illustrating the evaluation method according to this embodiment. [Figure 5] Figure 5 is a plan view showing the main configuration of the evaluation apparatus according to the modified example. [Figure 6] Figure 6 is a plan view showing the main components of the evaluation apparatus related to the modified example. [Figure 7] Figure 7 is a perspective view showing the configuration of the winding section included in the evaluation device relating to the modified example. [Modes for carrying out the invention]

[0012] The evaluation device according to the embodiment evaluates the vibration of a magnetic material. The evaluation device comprises a magnetic core, a plurality of winding sections, and a first measuring device. The magnetic core is made of a magnetic material. The magnetic core includes legs. The winding sections are arranged with gaps in the axial direction of the legs and are mounted on the legs so that the legs are exposed through the gaps. The winding sections are configured to excite the magnetic core by energizing it. The first measuring device measures the vibration of the legs (first configuration).

[0013] In the evaluation device according to the first configuration, multiple winding sections are attached to the legs of the magnetic core with gaps between them. The legs are exposed through the gaps between the winding sections. Therefore, for example, when measuring vibrations of the legs in the out-of-plane direction or in the in-plane direction (direction perpendicular to the axial direction of the legs), the gaps between the winding sections can be used. Thus, it is possible to measure the vibration of the legs to which the winding sections are attached.

[0014] Another evaluation device according to the embodiment evaluates vibrations of a magnetic material. The evaluation device comprises a plurality of winding sections and a first measuring device. The winding sections are arranged with gaps in their axial direction and can be attached to the legs of a magnetic core made of a magnetic material. The first measuring device measures the vibrations of the legs (second configuration).

[0015] In the evaluation apparatus according to the first or second configuration, each of the plurality of winding portions may include an exciting coil through which an exciting current flows (third configuration).

[0016] A large current flows through the exciting coil on the primary side (input side) as compared with the detection coil on the secondary side (output side), and a large Lorentz force is generated. As a result, large vibrations may occur at the location where the exciting coil is disposed among the leg portions of the magnetic core. In this regard, in the third configuration, since each of the winding portions includes an exciting coil, the exciting coils are arranged with a gap in the leg portions of the magnetic core. By using this gap, vibrations can be measured at the location where the exciting coil is disposed among the leg portions, that is, at the position of the exciting coil group through which a large current flows.

[0017] The evaluation apparatus according to any one of the first to third configurations may further include a jig. The jig is disposed on the leg portion in the gap between the winding portions and can fix the leg portion to the evaluation apparatus (fourth configuration).

[0018] For example, in a transformer, the magnetic core is used in a state fixed to a part of the transformer. When the magnetic core is formed by laminating electromagnetic steel sheets, the laminated electromagnetic steel sheets are compressed and fixed to a part of the transformer. Also, when measuring and evaluating the vibration of the magnetic core, it is preferable to reproduce the actual use state as much as possible. In the fourth configuration, the jig is disposed in the gap between the winding portions, and the leg portion of the magnetic core is fixed to the evaluation apparatus by this jig. Since the jig is disposed on the leg portion, a compressive force can be applied to the leg portion from its surface. Therefore, the force applied to the leg portion when actually used can be reproduced, and the vibration of the leg portion can be measured.

[0019] In the evaluation apparatus according to the fourth configuration, the jig may have a notch. The notch is formed, for example, on the surface of the jig facing the leg portion and penetrates the jig in the axial direction of the leg portion (fifth configuration).

[0020] In the fifth configuration, a notch is provided in the jig that secures the legs. This notch can also be used to measure the vibration of the legs.

[0021] In an evaluation apparatus relating to any of the first to fifth configurations, the first measuring device may be a laser Doppler vibrometer (sixth configuration).

[0022] An evaluation device relating to any of the first to sixth configurations may also include a plurality of first measuring devices. In this case, each of the first measuring devices may be configured to be adjustable in position relative to the leg portion (seventh configuration).

[0023] An evaluation device relating to any of the first to seventh configurations may be configured to adjust the excitation waveform based on pre-prepared output waveform information and to energize the winding section according to the excitation waveform (eighth configuration).

[0024] An evaluation device relating to any of the first to eighth configurations may further include a second measuring device. The second measuring device can measure information about the magnetic core that is different from the information measured by the first measuring device (ninth configuration).

[0025] An evaluation device relating to any of the first to ninth configurations may be configured to excite the magnetic core while changing the excitation conditions, and to measure the vibration of the leg portion with the first measuring device for each of the excitation conditions (tenth configuration).

[0026] An evaluation apparatus according to any of the first to tenth configurations may also include two first measuring devices. In this case, the first measuring devices are capable of irradiating laser light onto the measurement point on the leg from different directions. A light-shielding plate is provided adjacent to the measurement point between the laser light irradiation path from one of the first measuring devices to the measurement point and the laser light irradiation path from the other of the first measuring devices to the measurement point. The light-shielding plate prevents interference between the laser light irradiated from one of the first measuring devices and the laser light irradiated from the other of the first measuring devices (eleventh configuration).

[0027] The evaluation apparatus according to the 11th configuration is equipped with two first measuring devices. To prevent interference between the laser beams irradiated from these first measuring devices to the measurement points of the legs, a light-shielding plate is provided between the irradiation path of one laser beam from one first measuring device and the irradiation path of the other laser beam from the first measuring device. This improves the measurement accuracy of the leg vibrations by each of the first measuring devices.

[0028] The evaluation method according to the embodiment evaluates the vibration of a magnetic material. The evaluation method comprises the steps of preparing a magnetic core including legs and a plurality of winding sections, and exciting the magnetic core by energizing the winding sections and measuring the vibration of the legs with a measuring device. The magnetic core is made of a magnetic material. The winding sections are arranged with gaps in the axial direction of the legs and are mounted on the legs so that the legs are exposed through the gaps (12th configuration).

[0029] In the evaluation method relating to the 12th configuration, the vibration of the leg portion may be measured by a measuring device through the gap between the winding portions during the measurement step (13th configuration).

[0030] In the evaluation method relating to the 12th or 13th configuration, the magnetic core may include three legs. In this case, multiple winding sections are attached to each of the three legs. The connection method of the winding sections between the legs can be changed (14th configuration).

[0031] Embodiments of this disclosure will be described below with reference to the drawings. In each drawing, the same or equivalent components are denoted by the same reference numerals, and the same description will not be repeated.

[0032] [Evaluation device] Figure 1 is a plan view showing the main components of the evaluation device 100 according to this embodiment. Figure 2 is a side view of the evaluation device 100 shown in Figure 1. The evaluation device 100 is used to evaluate the vibration of a magnetic material. Referring to Figures 1 and 2, the evaluation device 100 comprises a magnetic core 10 to be evaluated, a plurality of winding sections 20, and a plurality of first measuring devices 31, 32, 33. The evaluation device 100 may further comprise a support frame 40, jigs 50, 60, a control device 70, and a second measuring device 80.

[0033] The magnetic core 10 and the winding section 20 are supported, for example, by a support frame 40. Figure 3 is an exploded perspective view showing the configuration of the magnetic core 10, the winding section 20, and the support frame 40.

[0034] Referring to Figure 3, the magnetic core 10 includes at least one leg 11. In this embodiment, the magnetic core 10 includes three legs 11. These legs 11 are arranged in parallel and connected by a yoke 12.

[0035] The magnetic core 10 is made of a magnetic material. The magnetic core 10 is, for example, a laminated iron core formed by laminating multiple steel plates. More specifically, in each layer, the steel plate for the leg portion 11 and the steel plate for the yoke 12 are separate, and the steel plates are laminated such that the joints between the steel plate for the leg portion 11 and the steel plate for the yoke 12 differ from layer to layer or from layer to layer. Typically, grain-oriented electrical steel sheets are used for the magnetic core 10. However, non-grained electrical steel sheets or amorphous alloy sheets may be used for the magnetic core 10. Furthermore, the magnetic core 10 is not limited to a laminated iron core, and may be, for example, a wound iron core. Alternatively, the magnetic core 10 may be a compacted iron core.

[0036] Multiple winding sections 20 are attached to at least one leg portion 11. In the example shown in Figure 3, multiple winding sections 20 are attached to each of the leg portions 11. In this embodiment, each winding section 20 includes a bobbin 21 and a coil 22. The bobbin 21 is made of a non-conductive material. The bobbin 21 has a cylindrical shape. The leg portion 11 is inserted into this bobbin 21. In the example shown in Figure 3, multiple independent winding sections 20 are formed at intervals from each other by independently winding the coil 22 around each of the multiple bobbins 21 that are spaced apart. The space between these multiple winding sections 20 (bobbins 21) is a portion where no winding section is provided, and this is referred to as a gap G.

[0037] The coil 22 is made of a conductive material. The coil 22 is configured to be wound around the leg portion 11. In this embodiment, the coil 22 is wound around the bobbin 21. The coil 22 includes at least one of a primary excitation coil and a secondary detection coil. The coil 22 may include both an excitation coil and a detection coil. For example, the coil 22 may include an excitation coil and a detection coil wound concentrically around the bobbin 21. In this case, the detection coil may be placed on top of the excitation coil, or the excitation coil may be placed on top of the detection coil. In the coil 22, the excitation coil and the detection coil are electrically insulated. Although not shown, the coil 22 may be covered with known insulating paper.

[0038] At least one leg 11 is provided with multiple winding sections 20. In this embodiment, each leg 11 is provided with multiple winding sections 20. For example, three or more winding sections 20 are provided for each leg 11. If, in a leg 11, each of the multiple winding sections 20 includes an excitation coil in the coil 22, these excitation coils are electrically connected in series. Similarly, if, in a leg 11, each of the multiple winding sections 20 includes a detection coil in the coil 22 in addition to the excitation coil, these detection coils are electrically connected in series. As in this embodiment, the magnetic core 10 and the winding sections 20 may constitute a model of a three-phase tripod transformer.

[0039] In at least one leg portion 11, the winding portions 20 are arranged in the axial direction of the leg portion 11 (longitudinal direction of the leg portion, Y direction in Figure 3) with a gap G between them. There is at least one gap G between the winding portions 20 arranged in the axial direction of the leg portion 11. The winding portions 20 are mounted on the leg portion 11 such that the leg portion 11 is exposed through the gap G between the winding portions 20. In this embodiment, since three or more winding portions 20 are provided for each leg portion 11, there are multiple gaps G in the row of winding portions 20 on the leg portion 11. The number of gaps G for each leg portion 11 may be, for example, two or more, or five or more. The size of each gap G in the axial direction of the leg portion 11 is preferably 1 mm or more. The size of each gap G in the axial direction of the leg portion 11 can be, for example, 50 mm or less. Furthermore, the size of each gap G may be 30 mm or less, and even 10 mm or less. For the sake of explanation, the axial direction of the leg portion 11 may be referred to as the Y direction. Also, the vertical direction on the plane of Figure 3 may be referred to as the Z direction, and the width direction of the leg portion 11 (the direction perpendicular to the Y and Z directions) may be referred to as the X direction.

[0040] The magnetic core 10 and the winding section 20 are placed on the support frame 40. Preferably, the magnetic core 10 is fixed to the support frame 40 by jigs 50, 60.

[0041] When the magnetic core 10 is fixed to the evaluation device 100 by a jig 50, at least one jig 50 is provided for each leg portion 11 having a gap G between the winding portions 20. The jig 50 is positioned on the leg portion 11 in the gap G between the winding portions 20. The jig 50 has a shape corresponding to the gap G between the winding portions 20. The jig 50 is provided in the gap G between the winding portions 20 so as to traverse the leg portion 11 in the X direction.

[0042] The jig 50 is fixed to, for example, the support frame 40. More specifically, the jig 50 is placed on the leg portion 11 and fastened to the support frame 40 on both sides in the X direction by fastening members 51 such as bolts. In this way, the leg portion 11 is fixed to the evaluation device 100 by the jig 50. That is, the leg portion 11 is compressed between the support frame 40 and the jig 50, and the leg portion 11 is fixed to the support frame 40.

[0043] The jig 50 may have at least one notch 52. In the example shown in Figure 3, the jig 50 includes a plurality of notches 52. These notches 52 are formed on the surface of the jig 50 facing the leg portion 11. Each of the notches 52 penetrates the jig 50 in the Y direction. Each notch 52 has a groove shape that extends from one winding portion 20 to the other winding portion 20 when the jig 50 is positioned in the gap G between two adjacent winding portions 20.

[0044] When the magnetic core 10 is fixed to the evaluation device 100 by a jig 60, the jig 60 is provided corresponding to each yoke 12 of the magnetic core 10. The jig 60 fixes the yoke 12 to, for example, a support frame 40. In the example in Figure 3, the jig 60 includes a jig body 61 and one or more retaining plates 62. The jig body 61 is placed on the yoke 12. As shown in Figure 3, the jig body 61 may be divided into multiple parts. The retaining plates 62 are placed on the jig body 61. The retaining plates 62 are fastened to the support frame 40 at multiple points by fastening members 63 such as bolts. As a result, the yoke 12 is fixed to the evaluation device 100 by the jig 60. That is, the yoke 12 is compressed between the support frame 40 and the jig 60, and the yoke 12 is fixed to the support frame 40.

[0045] The jig 60 may have at least one notch 64. In the example shown in Figure 3, the jig 60 includes a plurality of notches 64. The notches 64 are formed, for example, on the surface of the jig body 61 facing the yoke 12. Each of the notches 64 penetrates the jig body 61 in the Y direction. That is, each notch 64 has a groove shape extending from the yoke 12 side toward the leg portion 11 side. Each notch 64 is positioned, for example, in a location corresponding to one of the notches 52 provided on the jig 50 on the leg portion 11 side.

[0046] In Figures 1 and 2, the first measuring devices 31, 32, and 33 are measuring devices for measuring the vibration of the legs 11 of the magnetic core 10. The first measuring devices 31, 32, and 33 can measure the vibration (displacement) of the legs 11 when the magnetic core 10 is excited. The first measuring devices 31, 32, and 33 are typically laser Doppler vibrometers. However, the first measuring devices 31, 32, and 33 may be other vibrometers. For example, the first measuring devices 31, 32, and 33 may be non-contact vibrometers such as white light interferometers, capacitive displacement meters, or laser displacement meters, or they may be contact vibrometers. The first measuring devices 31, 32, and 33 can be appropriately selected from known vibrometers. Note that the first measuring device 32 is omitted in Figure 2.

[0047] In this embodiment, the first measuring device 31 is positioned above the magnetic core 10 to be evaluated. The first measuring device 31 is configured to be adjustable in position relative to the legs 11 of the magnetic core 10. More specifically, the relative positional relationship between the first measuring device 31 and the legs 11 can be adjusted in the X and Y directions.

[0048] Referring to Figure 2, the first measuring device 31 is attached to the running platform 312 via a mounting member 311. The first measuring device 31 may be detachable from the mounting member 311. The running platform 312 is movable in the Y direction. The running platform 312 travels, for example, along a rail 313 that extends in the Y direction near the support frame 40. As the running platform 312 moves in the Y direction, the position of the first measuring device 31 in the Y direction relative to the leg portion 11 (Figures 1 and 3) changes.

[0049] Referring to Figure 1, the running platform 312 is provided so as to straddle the support frame 40 that supports the magnetic core 10 in the X direction. Rails 312a are provided on the running platform 312. Rails 312a are positioned above the magnetic core 10 and extend in the X direction. The mounting member 311 moves in the X direction along the rails 312a. As the mounting member 311 moves in the X direction, the position of the first measuring device 31 in the X direction relative to the leg portion 11 changes.

[0050] Continuing with Figure 1, the first measuring device 32 is configured to allow adjustment of the position of the magnetic core 10 relative to the leg portion 11. More specifically, the relative positional relationship between the first measuring device 32 and the leg portion 11 is adjustable in the Y direction. The first measuring device 32 is attached to the running platform 321. The first measuring device 32 may be detachable from the running platform 321. The running platform 321 is movable in the Y direction. The running platform 321 travels, for example, along a rail 322 that extends in the Y direction near the support frame 40. As the running platform 321 moves in the Y direction, the position of the first measuring device 32 relative to the leg portion 11 changes in the Y direction.

[0051] The first measuring device 33 is configured to allow adjustment of the position of the magnetic core 10 relative to the leg portion 11. More specifically, the relative positional relationship between the first measuring device 33 and the leg portion 11 is adjustable in the X direction. As shown in Figures 1 and 2, the first measuring device 33 is attached to the running platform 331. The first measuring device 33 may be detachable from the running platform 331. The running platform 331 is movable in the X direction. The running platform 331 travels, for example, along a rail 332 that extends in the X direction near the support frame 40. As the running platform 331 moves in the X direction, the position of the first measuring device 33 relative to the leg portion 11 changes in the X direction.

[0052] Referring to Figures 1 and 2, the control device 70 is a computer including, for example, a central processing unit (CPU), main memory, auxiliary memory, input devices, and output devices. The control device 70 is connected to the first measuring devices 31, 32, and 33 directly or indirectly so as to be able to communicate with them. The control device 70 may also be connected to the first measuring devices 31, 32, and 33 via, for example, an A / D converter (not shown).

[0053] The control device 70 is also connected to an excitation power supply (not shown) for communication. The excitation power supply supplies excitation current to the excitation coils included in the winding section 20 at each of the legs 11 of the magnetic core 10. For example, an excitation current flows through the excitation coils when an AC voltage is applied to them by the excitation power supply. The excitation power supply includes, for example, an arbitrary waveform generator and a power amplifier.

[0054] In each leg 11 of the magnetic core 10, a detection coil included in the winding section 20 may be connected to, for example, a voltmeter (not shown). In this case, the control device 70 may be connected to the voltmeter directly or indirectly so as to be able to communicate with it.

[0055] The control device 70 may also be directly or indirectly connected to the second measuring device 80 for communication. The second measuring device 80 is configured to measure information about the magnetic core 10. The second measuring device 80 acquires information different from that of the first measuring devices 31, 32, and 33. Examples of the second measuring device 80 include a temperature sensor, an accelerometer, or a strain gauge. The second measuring device 80 should be positioned appropriately relative to the magnetic core 10 depending on the information to be measured. The evaluation device 100 may include one or more second measuring devices 80.

[0056] [Evaluation Method] Next, the evaluation method using the evaluation device 100 will be explained with further reference to Figure 4. Figure 4 is a flowchart illustrating the evaluation method according to this embodiment. In the evaluation method according to this embodiment, the vibration of the magnetic material constituting the magnetic core 10 is evaluated. The flowchart in Figure 4 includes not only the steps performed by the evaluation device 100, but also the steps performed by the evaluator of the vibration of the magnetic material. As shown in Figure 4, the evaluation method comprises a preparation step S1 and a measurement step S2.

[0057] (preparation process) In preparation step S1, the magnetic core 10 and multiple winding sections 20 are prepared (Figure 3). The magnetic core 10 and winding sections 20 are prepared by the evaluator. As described above, in the magnetic core 10 to be evaluated, two or more winding sections 20 are attached to at least one leg 11. In this embodiment, the magnetic core 10 and winding sections 20 constitute a model of a three-phase AC transformer.

[0058] (Measurement process) In measurement step S2, the magnetic core 10 is energized by energizing the winding section 20, and the vibration of the leg portion 11 is measured by one or more of the first measuring devices 31, 32, and 33. In this embodiment, for ease of understanding, the vibration measurement process will be explained by focusing on one of the multiple leg portions 11 included in the magnetic core 10.

[0059] At the start of the measurement process S2, the evaluator adjusts the position of one or more of the first measuring devices 31, 32, and 33 relative to the leg portion 11 to be measured (step S21). The first measuring devices 31, 32, and 33 may be moved manually by the evaluator or automatically by the control of the movement mechanism by the control device 70. The first measuring devices 31, 32, and 33 are moved, for example, to a position corresponding to the gap G of the winding portion 20.

[0060] Next, the evaluation device 100 starts energizing the winding section 20 attached to the leg section 11, thereby exciting the magnetic core 10 (step S22). Specifically, in response to the evaluator's operation, the control device 70 outputs a command signal to the excitation power supply (not shown), and the excitation power supply supplies an excitation current to the excitation coil of the winding section 20. The excitation power supply generates an excitation waveform based on the command signal from the control device 70 and generates an excitation current in the excitation coil according to this excitation waveform. For example, an excitation current may flow in the excitation coil by applying an AC voltage of the excitation waveform generated by the excitation power supply to the excitation coil. The excitation waveform applied to the excitation coil does not necessarily have to be a sine wave.

[0061] For example, the control device 70 reads pre-prepared output waveform information and adjusts the excitation waveform based on this output waveform information. The output waveform information is, for example, magnetic flux waveform information of the magnetic core 10, or waveform information of the current or voltage in the detection coil (detection waveform information). The output waveform information can be stored in advance in the auxiliary storage device of the control device 70. The control device 70 outputs the adjusted excitation waveform information to the excitation power supply. The excitation power supply energizes the winding section 20 according to the excitation waveform instructed by the control device 70. By energizing the winding section 20, magnetic flux is generated at the legs 11 of the magnetic core 10 with a waveform corresponding to the pre-stored magnetic flux waveform information, or current is generated in the detection coil of the winding section 20 with a waveform corresponding to the pre-stored detection waveform information. The excitation waveform may be derived from output waveform information such as magnetic flux waveform information or detection waveform information using a known calculation method.

[0062] With the magnetic core 10 excited and an alternating magnetic field generated, the vibration of the leg portion 11 is measured (step S23). The vibration measurement is performed using one or more of the first measuring devices 31, 32, and 33.

[0063] The first measuring device 31 can measure the out-of-plane (Z-direction) vibration of the leg portion 11 from the gap G between the winding portions 20. No jig 50 is placed in the gap G used for measurement by the first measuring device 31. For example, if the first measuring device 31 is a laser Doppler vibrometer, the first measuring device 31 can irradiate the surface of the leg portion 11 from the gap G between the winding portions 20 with laser light and measure the displacement of the leg portion 11 in the Z-direction by detecting the reflected light.

[0064] The first measuring device 32 can measure the in-plane (X-direction) vibration of the leg portion 11 from the gap G between the winding portions 20. No jig 50 is placed in the gap G used for measurement by the first measuring device 32. For example, if the first measuring device 32 is a laser Doppler vibrometer, the first measuring device 32 irradiates laser light from the gap G between the winding portions 20 toward the leg portion 11. In this case, it is preferable that a reflector (not shown) made of, for example, plastic is attached to the leg portion 11. The first measuring device 32 can detect the laser light reflected by the reflector and measure the displacement of the leg portion 11 in the X-direction.

[0065] The first measuring device 33 can measure the vibration of the leg portion 11 in the in-plane direction (Y direction). For example, if the first measuring device 33 is a laser Doppler vibrometer, the first measuring device 33 irradiates laser light toward the leg portion 11. In this case, it is preferable that a reflector (not shown) made of, for example, plastic is attached to the leg portion 11. The laser light can pass through the notches 52 and 64 of the jigs 50 and 60 and reach the reflector. The first measuring device 33 can detect the laser light reflected by the reflector and measure the displacement of the leg portion 11 in the Y direction.

[0066] The control device 70 receives vibration information of the leg portion 11 from one or more of the first measuring devices 31, 32, and 33. The vibration information is converted into a digital signal, for example, by an A / D converter and transmitted to the control device 70. The control device 70 stores the input vibration information.

[0067] When the magnetic core 10 is excited and an alternating magnetic field is generated, the control device 70 may acquire measurement information from the second measuring device 80 in addition to vibration information.

[0068] If multiple pre-prepared excitation conditions exist, the evaluation device 100 may change the excitation conditions and repeat the above measurement while maintaining the positions of the first measuring devices 31, 32, and 33 (steps S24, S22, S23). Multiple excitation conditions are stored in advance, for example, in the auxiliary storage device of the control device 70. The CPU of the control device 70 can automatically change the excitation conditions and perform vibration measurement by executing a predetermined program. The excitation conditions include frequency and magnetic flux density. The control device 70 energizes the winding section 20 and the magnetic core 10 according to the pre-set excitation conditions, for example, a combination of frequency and magnetic flux density. One or more of the first measuring devices 31, 32, and 33 measure the vibration of the leg section 11 for each excitation condition and transmit the measured information to the control device 70. The evaluation device 100 can repeat the measurement of the vibration of the leg section 11 while changing the excitation conditions, for example, until all the prepared excitation conditions are exhausted.

[0069] In this embodiment, the magnetic core 10 to be evaluated includes three legs 11, and each leg 11 is fitted with multiple winding sections 20. The evaluator can also change the wiring configuration of the winding sections 20 and perform the measurement step S2. In this embodiment, when excitation coils and detection coils are provided on the winding section 20 at each of the legs 11, the evaluator can switch the wiring configuration for the excitation coils and detection coils, respectively. In the case of a three-phase AC transformer model, the switchable wiring configurations are typically delta connection and star connection. The evaluation device 100 can measure the vibration of the legs 11 regardless of the wiring configuration.

[0070] [effect] Generally, the windings are attached to the legs (main legs) of a magnetic core without any gaps. That is, the windings are usually arranged closely to the legs so that they are not exposed. In contrast, in this embodiment, multiple windings 20 are attached to at least one leg 11 of the magnetic core 10 with gaps G between them. The leg 11 is exposed through the gaps G between the windings 20. By utilizing these gaps G, it becomes possible to measure the vibration of the leg 11 even within the range where the windings 20 are provided.

[0071] In this embodiment, the first measuring device 31 can measure the out-of-plane (Z-direction) vibration of the leg portion 11 from the gap G between the winding portions 20. Furthermore, the first measuring device 32 can measure the in-plane (X-direction) vibration of the leg portion 11 from the gap G between the winding portions 20. In addition, the first measuring device 33 can also measure the in-plane (Y-direction) vibration of the leg portion 11.

[0072] In this embodiment, vibration (displacement) of the leg portion 11 in the XYZ directions can be detected. From the displacement of the leg portion 11 in the XYZ directions, the magnetostriction (displacement per unit length) of the leg portion 11 in the XYZ directions can be calculated, taking into account the size of the leg portion 11. Therefore, the magnetostriction of the leg portion 11 can also be obtained.

[0073] In this embodiment, each of the first measuring devices 31, 32, and 33 is configured to be able to adjust its position relative to the leg portion 11, which is the object to be measured. Therefore, the first measuring devices 31, 32, and 33 can measure and acquire vibrations of the leg portion 11 at various positions.

[0074] In this embodiment, at least one leg portion 11 of the magnetic core 10 contains multiple winding portions 20, each containing an excitation coil. In the leg portion 11, electrically connected series excitation coils are arranged with a gap G between them. In this case, the gap G between the excitation coils can be used to measure vibrations at the location of the group of excitation coils in the leg portion 11 through which a large excitation current flows.

[0075] However, each of the winding sections 20 in the leg portion 11 does not necessarily have to include an excitation coil. Each of the winding sections 20 may include only an excitation coil and only a detection coil. For example, one or more winding sections 20 located on one side in the axial direction of the leg portion 11 may include only excitation coils, and one or more winding sections 20 located on the other side in the axial direction of the leg portion 11 may include only detection coils.

[0076] In this embodiment, a jig 50 may be provided in at least one of the gaps G that expose the leg portion 11. The jig 50 is positioned on the leg portion 11 in the gap G and fixes the leg portion 11 to the evaluation device 100. The jig 50 can apply a compressive force to the leg portion 11 from its surface. This allows the force that is actually applied to the leg portion 11 during use to be reproduced and the vibration of the leg portion 11 to be measured.

[0077] In this embodiment, the jig 50 may have at least one notch 52. Since the notch 52 penetrates the jig 50 in the Y direction, it can, for example, allow laser light irradiated from the first measuring device 33 and its reflected light to pass through. Therefore, even when the jig 50 is positioned in the gap G between the winding sections 20, the first measuring device 33 can measure the vibration of the leg section 11 in the Y direction at a position beyond the jig 50.

[0078] In this embodiment, the magnetic core 10 may be fixed to the evaluation device 100 by a jig 60. This allows the magnetic core 10 to be fixed in place and the vibration of the leg portion 11 to be measured. The jig 60 may have at least one notch 64. Since the notch 64 penetrates the jig 60 in the Y direction, it can pass through the laser light irradiated from the first measuring device 33 and its reflected light, similar to the notch 52 of the jig 50. Therefore, the vibration of the leg portion 11 in the Y direction can be measured by the first measuring device 33 without being obstructed by the jig 60.

[0079] The evaluation device 100 according to this embodiment may be configured to adjust the excitation waveform based on pre-prepared output waveform information and energize the winding section 20 according to the adjusted excitation waveform. The evaluation device 100 can excite the winding section 20 with various desired excitation waveforms, not just sine waves. For example, the excitation waveform applied to the excitation coil of the winding section 20 may be adjusted so that the magnetic flux waveform of the magnetic core 10, or the current or voltage waveform of the detection coil, becomes a sine wave.

[0080] In this embodiment, the second measuring device 80 may measure information about the magnetic core 10 that is different from the information measured by the first measuring devices 31, 32, and 33. This information is stored in, for example, the control device 70. The evaluator can then evaluate the vibration and magnetostriction of the legs 11 of the magnetic core 10, taking into account the measurement information obtained by, for example, the second measuring device 80.

[0081] The evaluation device 100 according to this embodiment may be configured to energize the magnetic core 10 while changing the excitation conditions, and to measure the vibration of the leg portion 11 using one or more of the first measuring devices 31, 32, and 33 for each excitation condition. This information is stored, for example, in the control device 70. The evaluation device 100 can obtain measurement information at the same measurement position but under different excitation conditions by, for example, measuring the vibration of the leg portion 11 while changing the excitation conditions while maintaining the positions of the first measuring devices 31, 32, and 33. The evaluator can then synthesize the vibration information obtained under different excitation conditions to evaluate the vibration and magnetostriction of the leg portion 11 of the magnetic core 10.

[0082] While embodiments relating to this disclosure have been described above, this disclosure is not limited to the embodiments described above, and various modifications are possible as long as they do not deviate from its spirit.

[0083] In the above embodiment, the evaluation device 100 includes a plurality of first measuring devices 31, 32, and 33 to measure the vibration of the leg portion 11 in three directions (X, Y, and Z directions). However, the evaluation device 100 only needs to include at least one of the first measuring devices 31, 32, and 33. For example, if the evaluation device 100 includes only one first measuring device 31, the first measuring device 31 can be used only to measure the vibration of the leg portion 11 in the out-of-plane direction (Z direction), or it can be used to measure vibrations in the in-plane direction (X and Y directions) in addition to the out-of-plane direction. That is, the first measuring device 31 may be moved and used, for example, from the travel platform 312 to the travel platform 321 or 331. The same applies to the first measuring devices 32 and 33. The first measuring devices 32 and 33 can be used for measuring vibrations in any of the X, Y, and Z directions.

[0084] If the evaluation device 100 includes two or more first measuring devices capable of measuring vibration, such as the first measuring devices 31, 32, and 33, the vibration of the leg portion 11 can be measured simultaneously in two or more directions among the XYZ directions. For example, as shown in Figure 5, the vibration of the leg portion 11 at measurement point P may be measured simultaneously by each of the first measuring devices 32 and 33. In Figure 5, the winding portion 20 and jigs 50 and 60 are omitted to avoid complexity in the drawing.

[0085] Referring to Figure 5, the first measuring devices 32 and 33 can irradiate laser light onto the measurement point P of the leg portion 11 from different directions. Specifically, the first measuring device 32 can irradiate laser light onto the measurement point P in the X direction, and the first measuring device 33 can irradiate laser light onto the measurement point P in the Y direction. The measurement point P is located in the leg portion 11, corresponding to the gap G between the winding portions 20 (Figures 1 to 3). A reflector, for example, is attached to the measurement point P of the leg portion 11.

[0086] A light-shielding plate 23 may be provided between the laser beam irradiation path R1 from the first measuring device 32 to the measurement point P and the laser beam irradiation path R2 from the first measuring device 33 to the measurement point P. The light-shielding plate 23 is positioned adjacent to the measurement point P. The light-shielding plate 23 is positioned, for example, next to the reflector on the leg portion 11. In the example of Figure 5, the light-shielding plate 23 has a straight shape when viewed along the direction perpendicular to both the laser beam irradiation paths R1 and R2 of the first measuring devices 32 and 33 (Z direction). However, the light-shielding plate 23 may have a substantially L-shape when viewed along the direction perpendicular to both the irradiation paths R1 and R2, as shown in Figure 6. The light-shielding plate 23 is positioned, for example, inside the bobbin 21 (Figure 3) of the winding portion 20. In the evaluation device 100, a single light-shielding plate 23 may be provided for the measurement point P, or a plurality of light-shielding plates 23 may be provided.

[0087] The light-shielding plate 23 is a plate-shaped member that prevents interference between the laser light emitted from the first measuring device 32 and the laser light emitted from the first measuring device 33. By preventing interference between the laser light beams from the first measuring devices 32 and 33 heading towards the measurement point P, the measurement accuracy of the vibration of the leg portion 11 by each of the first measuring devices 32 and 33 can be improved.

[0088] In the examples shown in Figures 5 and 6, the vibration of the leg portion 11 at measurement point P in the X and Y directions is measured simultaneously by the first measuring devices 32 and 33. However, the vibration of the leg portion 11 at measurement point P in the Z and Y directions may be measured simultaneously by the first measuring devices 31 and 33, or the vibration of the leg portion 11 at measurement point P in the Z and X directions may be measured simultaneously by the first measuring devices 31 and 32. Alternatively, the vibration of the leg portion 11 at measurement point P in the Z, X, and Y directions may be measured simultaneously by the first measuring devices 31, 32, and 33. Even in these cases, a light-shielding plate 23 may be provided between the irradiation paths of the laser beams of the two or more first measuring devices to prevent interference between the lasers irradiated toward measurement point P from the two or more first measuring devices.

[0089] Alternatively, the vibration of the leg portion 11 may be measured at multiple locations in the same direction using multiple first measuring devices. For example, when measuring vibration in the Y direction at multiple locations on the leg portion 11, multiple first measuring devices are prepared, and reflectors are placed at different positions in the Y direction on the surface of the leg portion 11. Then, by irradiating each reflector with, for example, laser light from the corresponding first measuring device, the vibration (displacement) of the leg portion 11 in the Y direction at each position can be measured. For example, by taking the difference in vibration at multiple measurement positions, the elongation of the leg portion 11 between measurement positions can be obtained. Similarly, vibration can also be measured at multiple measurement positions on the leg portion 11 in the X and Z directions.

[0090] In the above embodiment, the configuration of the evaluation device 100 and its usage method were described together, so the evaluation device 100 is equipped with the magnetic core 10 to be evaluated. However, at times when the evaluation of vibrations of the magnetic material is not being performed, such as when the evaluation device 100 is in circulation, the magnetic core 10 does not need to be installed in the evaluation device 100. In other words, the magnetic core 10 to be evaluated does not need to be mounted on the winding section 20 in advance. The evaluation device 100 can be equipped with a plurality of winding sections 20 and at least one of the first measuring devices 31, 32, and 33. In this case, in the evaluation device 100, the plurality of winding sections 20 are arranged with gaps in the axial direction of the winding section 20.

[0091] In the above embodiment, the first measuring devices 31, 32, and 33 are moved in order to adjust the positional relationship between the leg portion 11 to be measured and the first measuring devices 31, 32, and 33. However, it is sufficient to adjust the relative position of the first measuring devices 31, 32, and 33 with respect to the leg portion 11, and for example, it is also possible to move the support frame 40 that supports the magnetic core 10.

[0092] In the evaluation device 100 according to the above embodiment, the winding sections 20 are arranged with a gap G in their axial direction. Therefore, when attaching the winding sections 20 to the legs 11 of the magnetic core 10, the legs 11 may catch on the winding sections 20 at the position of the gap G, which can make it time-consuming to attach the winding sections 20 to the legs 11. To address this, the evaluation device 100 may be equipped with a base plate 24, as shown in Figure 7. The base plate 24 is inserted into the bobbin 21 of each winding section 20 and extends in the direction of the arrangement of the winding sections 20. In this case, the legs 11 (Figure 1) of the magnetic core 10 can be inserted into the winding sections 20 on the base plate 24. This prevents the legs 11 from catching on the winding sections 20 at the position of the gap G, and allows the winding sections 20 to be attached to the legs 11 smoothly. [Explanation of symbols]

[0093] 100: Evaluation device 10:Magnetic core 11: Legs 20: Winding section 22: Coil (excitation coil) 31,32,33: 1st measuring device 50: Jig 52: Notch 80:Second measuring device

Claims

1. An evaluation device for evaluating the vibration of magnetic materials, The aforementioned magnetic material comprises a magnetic core including legs, A plurality of winding sections are arranged with gaps in the axial direction of the leg and are attached to the leg such that the leg is exposed from the gap, and are configured to excite the magnetic core by energization, A first measuring device for measuring the vibration of the leg portion, An evaluation device equipped with the following features.

2. An evaluation device for evaluating the vibration of magnetic materials, Multiple winding sections are arranged with gaps in the axial direction and can be attached to the legs of the magnetic core made of the magnetic material, A first measuring device for measuring the vibration of the leg portion, An evaluation device equipped with the following features.

3. An evaluation apparatus according to claim 1 or 2, The evaluation device comprises a plurality of winding sections, each including an excitation coil through which an excitation current flows.

4. An evaluation apparatus according to claim 1 or 2, further, A jig positioned on the leg portion in the aforementioned gap, which fixes the leg portion to the evaluation device. An evaluation device equipped with the following features.

5. An evaluation apparatus according to claim 4, The jig is an evaluation device having a notch formed on a surface facing the leg portion and penetrating the jig in the axial direction.

6. An evaluation apparatus according to claim 1 or 2, The first measuring device is an evaluation device which is a laser Doppler vibrometer.

7. An evaluation apparatus according to claim 1 or 2, The device comprises multiple of the first measuring devices, Each of the first measuring devices is configured to be adjustable in position relative to the legs, and is an evaluation device.

8. An evaluation apparatus according to claim 1 or 2, An evaluation device configured to adjust the excitation waveform based on pre-prepared output waveform information and to energize the winding section according to the excitation waveform.

9. An evaluation apparatus according to claim 1 or 2, further, A second measuring device that measures information different from the information measured by the first measuring device regarding the magnetic core, An evaluation device equipped with the following features.

10. An evaluation apparatus according to claim 1 or 2, An evaluation device configured to energize the magnetic core while changing the excitation conditions, and to measure the vibration of the leg portion using the first measuring device for each of the excitation conditions.

11. An evaluation apparatus according to claim 1 or 2, The system comprises two of the aforementioned first measuring devices, The first measuring device is capable of irradiating the measurement points of the leg portion with laser light from different directions. An evaluation apparatus in which a light-shielding plate is provided adjacent to the measurement point between the laser beam irradiation path from one of the first measuring devices to the measurement point and the laser beam irradiation path from the other of the first measuring devices to the measurement point, in order to prevent interference between the laser beam irradiated from one of the first measuring devices and the laser beam irradiated from the other of the first measuring devices.

12. An evaluation method for evaluating the vibration of magnetic materials, A step of preparing a magnetic core made of the aforementioned magnetic material and including legs, and a plurality of winding portions arranged with gaps in the axial direction of the legs and attached to the legs such that the legs are exposed from the gaps, The process involves energizing the magnetic core by supplying current to the winding portion and measuring the vibration of the leg portion using a measuring device. An evaluation method comprising the following features.

13. The evaluation method according to claim 12, The evaluation method involves measuring the vibration of the leg portion through the gap using the measuring device in the measurement step.

14. The evaluation method according to claim 12, The magnetic core includes three legs, each of which is attached to the plurality of winding sections. An evaluation method in which the connection method of the winding portion between the legs is changed.

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