JPS61224308A - Gapped core type reactor - Google Patents

Abstract

PURPOSE:To prevent the generation of leakage flux running at right angle to the directivity of a magnetic shield as well as to contrive reduction in loss of a magnetic shield by a method wherein a horseshoe-shaped magnetic shield is provided at the end of a winding on the outside of the core window only. CONSTITUTION:Outside the core window 8 formed by a core leg 3, side legs 4a and 4b, yoke cores 5a and 5b and the like, the horseshoe-shaped magnetic shield 9a, 9b and the like, the on which a grain-oriented silicon steel plate is radially laminated in such a manner that they have the directivity between the cores 5a and 5b, and clamping plates 7a and 7b in radial direction of a winding 6, are provided in such a manner that they are laminated on the upper and the lower parts of the winding 6 on the side (on the side of the winding 6) inner than the cores 5a and 5b. By having the constitution above-mentioned, the leakage flux phi directly flows into the cores 5a and 5b in the core window 8, and therefore, the leakage flux does not flow in the direction at right angle to the enabling to sharply reduce the loss of the shields of 9a, 9b and the like.

Description

[Detailed Description of the Invention] [Technical Field of the Invention J] The present invention relates to an iron-core reactor with a gap,
In particular, the present invention relates to improvements in magnetic shields that are placed on the windings and at their lower ends to prevent magnetic flux leakage.

[Technical Background of the Invention and its Problems] Conventionally, gapped iron core reactors have been generally used as reactors for shunt reactors and the like. This gapped iron core type reactor consists of a plurality of block iron cores formed by laminating silicon steel strips, which are stacked together via a plurality of magnetic gaps to form the iron core legs. A yoke core formed by laminating strips is placed,
It is constructed by winding a winding around the core leg. A gap member made of an insulator is generally interposed in the gap portion.

In such a gapped core type reactor, in order to reduce leakage magnetic flux from the winding ends, twists that are not necessary for air insulation are placed on the upper and lower ends of the windings, and a ring-shaped magnetic field that passes through the core window is placed. A shield is provided. Conventional magnetic shielding uses a radial core-shaped ring in which grain-oriented silicon steel strips are laminated radially so that it has directionality in the radial direction. It is placed through the. When a magnetic shield is provided in this way, the leakage magnetic flux at the end of the winding is effectively collected by the magnetic shield and returned to the core legs, which reduces winding eddy current loss due to fringing magnetic flux, and reduces the loss of winding eddy currents in structural materials such as links. Stray losses that occur can also be reduced. However, with such a ring-shaped magnetic shield that penetrates the core window, the leakage magnetic flux flows radially along the directionality of the magnetic shield outside the core window, and is not effective without causing large losses. Demonstrates the effect of reducing leakage magnetic flux. However, since the yoke core and the magnetic shield are close to each other within the core window, much of the leakage magnetic flux passes through the magnetic shield and flows into the yoke core.

Since this direction is perpendicular to the directionality of the magnetic shield, a large loss occurs in this portion, which has the drawback of reducing the loss reduction effect of the magnetic shield.

[Object of the invention] The present invention provides an iron core reactor with a gap that eliminates the above-mentioned drawbacks, reduces the loss of the magnetic shield itself, and further reduces the melting current and stray loss due to leakage magnetic flux. With the goal.

[Summary of the Invention] In order to achieve the above object, the present invention provides a horseshoe-shaped magnetic shield at the end of the winding only outside the core window, and does not provide a magnetic shield inside the core window. This eliminates the leakage magnetic flux that flows through the magnetic shield at right angles to its directionality, reducing the loss of the magnetic shield itself.

[Embodiment of the Invention] An embodiment of the present invention will be described below with reference to the drawings. 1st
In the figures to FIG. 4, a plurality of block cores 1 are stacked with magnetic gaps 2 in between to form a core leg 3, and this core leg 3 is connected to a yoke from above and below together with left and right side legs 4a and 4b. It is sandwiched between iron cores 5a and 5b. A winding 6 is wound around the core leg 3, and above and below the winding 6 are clamping plates 7a made of an insulator.

7b is arranged, and the winding 6 is tightened by a tightening device (not shown). Furthermore, iron core legs 3, side 1fl14a, 4b.

Outside the core window 8 formed by the yoke cores 5a, 5b, etc., the yoke cores 5a, 5b and the clamping plate 7
a.

Horseshoe-shaped magnetic shields 9a, 9b as shown in FIG. 4 are made of grain-oriented silicon steel plates laminated radially between the wires 7b and 7b so as to have directionality in the radial direction of the winding 6.

9c and 9d are provided. This magnetic shield 9a
, 9b, 9G, and 9d are inside the yoke cores 5a and 5b (
They are arranged so as to overlap the upper and lower ends of the winding 6 on the winding 6 side).

With such a configuration, the leakage magnetic flux φ outside the iron core window 8 is caused by the magnetic shield 9 as shown in FIG.
a, 9b,, 9C, 9d 1. :・Flows along the direction and flows into the core leg 3, and within the core window 8, flows directly into the yoke cores 5a and 5b as shown in FIG. As can be seen from the flow of this leakage magnetic flux φ, even in the configuration using such a horseshoe-shaped magnetic shield, the leakage magnetic flux φ effectively flows to the core leg 3 or the yoke cores 5a and 5b, so that the fringe of the winding 61' portion It can significantly reduce winding eddy current due to magnetic flux and stray loss generated in tanks, etc.

Furthermore, within the core window 8, the leakage magnetic flux φ is directly transmitted to the yoke core 5a.

5b, so magnetic shields 9a, 9b, 9C.

It does not flow in a direction perpendicular to the directionality of 9d. For this reason, magnetic shields 9a, 911, 9C.

The loss of 9a itself can also be significantly reduced.

Further, since the winding 8 is tightened by the tightening plates 7a, 7b, magnetic shields 9a, 9b, 9c are provided.

9d does not need to have a large mechanical strength, so its thickness can be reduced to the necessary minimum and it can be made compact.

[Effects of the Invention] As described above, according to the present invention, outside the window of the iron core, a horseshoe-shaped magnetic field having directionality in the radial direction of the winding is formed so as to overlap the end of the winding on the winding side of the yoke core. Since the shield is provided, the loss of the magnetic shield itself is reduced, and it is possible to obtain an iron core reactor with a gap that further reduces the wax current and stray loss due to leakage magnetic flux.

[Brief explanation of the drawing]

FIG. 1 is a front view showing one embodiment of the present invention, FIG. 2 is a side view of the same, FIG. 3 is a plan view of the same, and FIG. 4 is a plan view showing a magnetic shield. 1...Block core, 2...Gap, 3...
Core legs, 4a, 4b... Side legs, 5a, 5b... Yoke core, 6... Winding wire, 8... Core window, 9a, 9
b, 9c, 9d...magnetic shield. Applicant's agent Patent attorney Takehiko Suzue District 1 D Figure 2

Claims (1)

[Claims] A core leg is formed by stacking multiple block cores through magnetic gaps, winding is wound around this core leg, and this core leg is sandwiched between upper and lower yoke cores along with side legs. In the core type reactor, a horseshoe-shaped magnetic shield having directionality in the radial direction of the winding is provided outside the window of the iron core on the winding side of the yoke core so as to overlap the end of the winding. An iron core reactor with a gap.