JP2002033224A - Stationary inductor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve the problem that conventionally electromagnetic steel sheets 12 of a central leg 2 and yoke 5 lapped by vibration energy caused by magnetostriction are mutually rugged and turn into noises since the central leg 2 and the yoke 5 are mutually lapped in a bonding part 30 formed between the central leg 2 and the yoke 5 for linking the central leg 2 and a side leg 4. SOLUTION: A wedge part 9 is located between a bonding part 30 and a tank 8, a resonant void part 34 is provided in this wedge part 9, an opening part 35 of this resonant void part 34 is located, while facing the bonding part 30 and noises are reduced by resonating the resonant void part 34 and the opening part 35 with noises caused by the magnetic vibrations of the bonding part 30.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a stationary inductor, and more particularly to a stationary inductor suitable for use in a vehicle.

[0002]

2. Description of the Related Art A conventional stationary inductor mounted on a vehicle is configured such that a coil of a transformer for a vehicle wound around an iron core is housed in a tank. The tank usually has a box-shaped structure and includes an iron core storage part and coil storage parts extending to both ends from the iron core. The tank also serves as an electrical ground. The iron core is configured as follows. Place the side legs on both sides of the center leg, connect the center leg and the side legs with the upper yoke and the lower yoke, and between the center leg and the upper yoke and the lower yoke, each yoke and the side A joint for joining between the legs is provided.
The center leg, the side legs, and the yoke are configured by laminating a plurality of electromagnetic steel plates. The coil wound around the center leg is housed in a tank, and the tank is filled with an insulating medium.

[0003] An iron core magnetic path is formed, for example, on the left side by a path between the center leg and the upper yoke and between the upper yoke and the side leg and between the side leg and the lower yoke and the center leg. A similar iron core magnetic path is also formed on the right side. Magnetic flux flows through these iron core magnetic paths.

In general, the magnetic flux differs in magnitude between the apex of the sine wave curve of the AC voltage and the zero point, and the alternation of the magnetic flux may cause the electromagnetic steel sheet to extend in the direction of the magnetic flux flowing through the electromagnetic steel sheet forming the iron core magnetic path. Vibration and noise are generated by vibration energy caused by contraction or so-called magnetostriction.

This noise is particularly significant at the joint between the center leg and each yoke and at the joint between each yoke and the side leg. In these joints, for example, the center leg and the upper yoke wrap each other at the joints, so that magnetostriction is concentrated at the cut portion of the lap, and the magnetic attraction force generated when passing from iron plate to iron plate causes the central portion to overlap. The legs and the upper yoke rub against each other, resulting in noise.

[0006]

Generally, in a stationary inductor for a vehicle, an iron core, a joint, and a coil vibrate due to an electromagnetic induction action during operation of the stationary inductor, and the vibration is transmitted to a tank via an insulating structure. The two main routes are solid propagation through the air or air through a cooling insulating oil and a tank. For this reason, most of the noise of the stationary stationary inductor for the vehicle felt by the vehicle body is transmitted to the vehicle body through the tank through air, or the vibration of the tank is directly transmitted to the mounting legs of the stationary stationary inductor for the vehicle and solidified on the vehicle body. Probable propagation.

In particular, in recent years, the main converter, which is a device mounted on a vehicle, has been driven at a higher frequency in accordance with the advancement of advanced power electronics elements for the purpose of energy saving, and has been operated in a frequency range such as several kilohertz, which has not particularly existed until now. It has come to be used. In particular, since noise in the frequency range of several kHz is considered to be unpleasant to human hearing, it has been demanded to reduce the noise.
As a measure to reduce noise, Japanese Utility Model Application Laid-Open No. 58-12962
No. 5 can be mentioned. This publication does not consider the noise at the joint.

[0008] It is an object of the present invention to provide a stationary inductor with reduced noise.

[0009]

SUMMARY OF THE INVENTION A feature of the present invention is that a wedge portion is arranged between a tank and a joint for joining each leg and the yoke, and a resonance cavity is provided in the wedge portion. An object of the present invention is to reduce noise by arranging an opening provided in the resonance-type cavity so as to face the joint, so that noise caused by magnetic vibration of the joint and the resonance-type cavity and the opening resonate.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings shown in FIGS.

The three-phase iron core 1 is formed by connecting a center leg 2 and left and right side legs 3 and 4 with an upper yoke 5 and a lower yoke 6. A coil 7 is mounted on the center leg 2. The iron core 1 and the coil 7 are housed in a tank 8.
A wedge 9 is inserted between the side surface of the iron core 1 and the tank 8. A wedge 10 is provided between the iron core 1 and the tank 8 and the coil 7.
Is inserted. Insulation material 1 between coil 7 and tank 8
1 is inserted. The tank 8 is filled with insulating oil 33.

The center leg 2 and the left and right side legs 3, 4 and the upper yoke 5 and the lower yoke 6 are formed by laminating a plurality of electromagnetic steel plates 12 cut into shapes as shown in FIGS. are doing. Between the center leg 2 and the upper yoke 5 and the lower yoke 6, each yoke 5, 6
Joints 30 and 31 are formed between and the side legs 3 and 4, respectively.

In this embodiment, as shown in FIG. 3, the left side leg 3 and the center leg 2 are connected by an upper yoke 5 and a lower yoke 6 to form an iron core magnetic path 20. . The right side leg 4 and the center leg 2 are connected by an upper yoke 5 and a lower yoke 6 to form an iron core magnetic path 21. These core magnetic paths 2
A magnetic flux Φ flows through 0 and 21 in the direction of the arrow.

In general, the magnitude of the magnetic flux differs between the vertex of the sine wave curve of the alternating current and the zero point, and the magnitude of the magnetic flux causes the electromagnetic steel sheet to expand (Y1) or shrink in the direction of the magnetic flux flowing through the electromagnetic steel sheet 12. (Y2) Vibration and noise are generated by vibration energy due to so-called magnetostriction.

In the joint portion 30, the central leg 2 and the magnetic steel plates of the upper yoke 5 and the lower yoke 6 are wrapped and joined to each other. The wrap 32 is not shown except in FIGS. 3 to 7, but is wrapped at the joint in the same manner as in FIGS. The wedge 9 is arranged between the joints 30 and 31 and the tank 8.

The wedge 9 has the structure shown in FIG. On the opposing surfaces 9A and 9B of the wedge 9 facing the iron core 1 and the tank 8, the width W between the opposing surfaces is changed from the upper surface 9c of the wedge 9 to the lower surface 9c.
An inclined surface 9E gradually narrows toward D. A round resonance cavity 34 is formed penetrating from the upper surface 9c to the lower surface 9D of the wedge portion 9, and the resonance cavity 3 is formed.
4 has an opening 35 cut out on an opposing surface 9 </ b> A opposing the iron core 1. The opening 35 is arranged to face the joints 30 and 31.

Next, the operation of the resonant cavity 34 will be described. The direction of the magnetic flux flowing through the magnetic steel sheet 12 is
Vibration is generated by vibration energy due to so-called magnetostriction in which 2 expands (Y1) or contracts (Y2). For example, as shown in FIG. 6, the vibration causes the electromagnetic steel plates 12 to rub against each other at 32 laps of the joint portion 30 to generate noise.
When noise enters the opening 35 and the resonance-type cavity 34,
Resonance occurs with the resonance-type cavity 34 and the opening 35, so that noise is absorbed and reduced by the resonance-type cavity 34, and vibrations in the resonance-type cavity 34 propagate through the wedge 9 and the insulating oil 33. In the meantime, the noise in the tank can be reduced.
As a result, noise transmitted directly from the tank to the vehicle can be reduced. In particular, the resonance type cavity 34 can absorb noise of several kHz in a high frequency region.

If the resonance cavity 34 is formed in an arc shape such as a round shape or an elliptical shape, the resonance cavity 3 is formed.
The vibration of 4 hardly causes crack damage. Further, the opposing surfaces 9A, 9
Since the thickness 9F of B is thinner than the thickness 9G in the perpendicular direction,
It is easy to vibrate to cancel noise, and it is easier to absorb noise and reduce noise.

The resonant cavity 34 is designed to have the same natural vibration frequency as the excitation vibration frequency of the joint 30. As the material of the wedge portion 9, wood, FRP
For example, a somewhat flexible press board, polyamide, or the like is used as the adjusting member 39, and these members are used in combination. 7, the joint 31 is formed between the upper and lower yokes 5, 6 and the side legs 3, 4, and the wedge 9 is disposed between the joint 31 and the tank 8. The wedge portion 9 is provided with a resonance-type cavity portion 34, and an opening 35 of the resonance-type cavity portion 34 is arranged to face the joint portion 31. Even with such a configuration, the same operation and effect as described above can be achieved, and thus detailed description is omitted.

Further, the joints 30 and 31 form a substantially triangular projection 37 by the electromagnetic steel plate 12. For example, since the projections 37 of the center leg 2 are arranged so as to face the openings 35, when the electromagnetic steel plates 12 rub against each other at the lap 32 of the joint 30, the projections 3 are formed by the openings 35.
The wedge portion 9 and the wedge portion 9 are prevented from sliding directly to reduce noise and prevent damage to both.

Next, another embodiment of the present invention will be described with reference to FIG. 8 to FIG.
Only 0 is described, and the description of the joint 31 is omitted. The shape of the resonance-type cavity 34 in FIGS. 8 and 9 is formed in a rectangular shape, and the resonance-type cavity 34 and the joint 30 are arranged to face each other. A slit 36 is formed between the resonance cavity 34 shown in FIG. The functions and effects of these resonance-type cavities 34 are the same as those described above. Further, as shown in FIGS. 8 and 10, the opening 35 and the resonance-type cavity 34 may be arranged to face the iron core 1.

[0022]

As described above, according to the present invention, it is possible to reduce the vibration and noise generated at the joint.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view of a stationary inductor shown as an embodiment of the present invention.

FIG. 2 is a perspective view of an iron core used in FIG.

FIG. 3 is a plan view showing an iron core magnetic path used in FIG. 1;

FIG. 4 is a sectional view taken along line AA of FIG. 1;

FIG. 5 is a perspective view of a wedge used in FIG. 4;

FIG. 6 is a plan view showing a main part near a joint in FIG. 4;

FIG. 7 is a plan view of a main part near a joint formed between the yoke and the side leg in FIG. 4;

FIG. 8 is a plan view of an iron core of a stationary inductor shown as another embodiment of the present invention.

FIG. 9 is a plan view of an iron core of a stationary inductor shown as another embodiment of the present invention.

FIG. 10 is a plan view of an iron core of a stationary inductor shown as another embodiment of the present invention.

[Explanation of symbols]

1 ... iron core, 2 ... center leg, 3, 4 ... side leg, 5 ... tank, 6
... lower yoke, 7 ... coil, 8 ... tank, 9 ... wedge part, 12
... Electromagnetic steel plate, 13 ... Laminated iron plate, 30, 31 ... Junction, 3
2 ... wrap, 33 ... insulating oil, 34 ... resonant cavity, 35
... Opening, 36, slit, 37, protrusion, 38, scissors, 39, adjusting material.

Claims (4)

[Claims] 1. A side leg disposed on both sides of a center leg, a yoke connected between the center leg and the side leg, and a joint portion connecting the center leg and the side leg with the yoke. In a stationary inductor including an iron core, a coil wound around the center leg, and a tank that stores the iron core and the coil, a wedge portion is disposed between the joint and the tank. A stationary portion provided with a resonance-type cavity portion that resonates with a frequency of noise caused by magnetic vibration of the joining portion to muffle the noise, and an opening of the resonance-type cavity portion is arranged to face the joining portion. Inductor. 2. The vehicle according to claim 1, further comprising a side leg disposed on both sides of the center leg, a yoke connecting the center leg and the side leg, and a joint for connecting the center leg and the side leg to the yoke. In a stationary inductor including an iron core, a coil wound around the center leg, and a tank that stores the iron core and the coil, a wedge portion is disposed between the joint and the tank. A resonance-type cavity that resonates with the frequency of noise due to magnetic vibration of the joint to muffle the noise, forms an opening in the resonance-type cavity, and the opening is formed in the joint. A stationary inductor which is disposed so as to face a triangular protrusion. 3. A side leg disposed on both sides of the center leg, a yoke connecting the center leg and the side leg, and a joint for connecting the center leg and the side leg to the yoke. In a stationary inductor including an iron core, a coil wound around the central leg, and a tank that stores the iron core and the coil, a wedge portion is disposed between the joint and the tank, A stationary inductor comprising: a resonance-type cavity that resonates with a frequency of noise caused by magnetic vibration to muffle noise; and an opening of the resonance-type cavity is disposed to face the iron core. 4. The stationary inductor according to claim 1, wherein a flexible adjusting member is disposed between the wedge portion and the iron core.