JPH04116812A - Reactor using iron core with gap - Google Patents

Abstract

PURPOSE:To reduce the iron loss due to the fringing magnetic flux thereby further reducing the iron loss by a method wherein the grain orientation of the silicon steel plates on the outermost side and the innermost side of the block iron core formed of the blanks made of the grain oriented silicon steel plates radially laminated is specified to be rectangular to the direction of the main magnetic flux. CONSTITUTION:A leg 1 of iron core with gaps is composed of a plurality of laminated block iron cores 1a circular in section formed of grain oriented silicon steel plates made blanks radially laminated through the intermediary of a magnetic gap 2 comprising magnetic gap member made of insulator. On the other hand, the grain direction of the blanks on the outermost side 1b and the innermost side 1c in a block iron core 1a is specified to be rectangular to the direction of the main magnetic flux 11.

Description

[Detailed description of the invention] [Object of the invention] (Industrial application field) The present invention relates to an iron core reactor with a gap,
In particular, it relates to improvements in iron core structure for suppressing the occurrence of iron loss due to fringing of the main magnetic flux and reducing loss.

(Prior Art) As a reactor used for a shunt reactor or the like, an iron core reactor with a gap is generally used. This gapped core reactor consists of a plurality of block cores with circular cross-sections, which are formed by stacking punched grain-oriented silicon steel plates radially so that the direction of the main magnetic flux and its directionality match.
By inserting a magnetic gap member made of an insulator between the block cores, the block cores are stacked up via a plurality of magnetic gaps to form gapped core legs, and the same magnetic gap members are placed above and below the block cores. A yoke core with a rectangular cross section formed by laminating raw steel plates is arranged, and a winding is wound around the gapped core legs.

(Problem to be Solved by the Invention) By the way, in the gapped iron core reactor configured in this way, a so-called fringing phenomenon occurs in which the main magnetic flux in the iron core leaks to the outside at the gap portion without passing through the gap. Therefore, loss occurs in the outer or inner core, and reducing the loss in the silicon steel plate in that area has been a major problem. The causes of this loss can be roughly divided into eddy current loss that occurs when the fringing magnetic flux is incident on the silicon steel plate, and iron loss that occurs along the flow of the magnetic flux after the incidence. Eddy current loss increases approximately in proportion to the square of the thickness of a silicon steel sheet. Generally, the thickness of a silicon steel sheet is about 0.3+n, so eddy current loss is not a particular problem, but iron loss Since the flow direction of the fringing magnetic flux deviates from the directionality of the silicon steel plate, a large loss occurs, which poses a problem.

In view of the above points, an object of the present invention is to provide an iron-core reactor with a gap that further reduces loss by reducing loss, particularly iron loss, occurring in the silicon steel plate at the gap portion. .

[Structure of the invention]

(Means for Solving the Problems) The gapped core reactor of the present invention has a block core formed by stacking punched grain-oriented silicon steel plates in a radial manner. It is characterized in that it is made perpendicular to the direction in which the main magnetic flux flows, and is aligned with the incident direction of the fringing magnetic flux generated in the gap portion.

(Function) In this way, the flow of the fringing magnetic flux matches the directionality of the silicon steel plate at the outermost and innermost portions of the iron core, making it easier to flow, thereby reducing iron loss in those portions.

(Example) Hereinafter, an example of the present invention will be described with reference to the drawings in the case of a single-phase three-leg core reactor with a gap.

In FIG. 1, a plurality of block iron cores 1a each having a circular cross section formed by laminating radially cut grain-oriented silicon steel sheets are connected through a magnetic gap 2 made of a magnetic gap member made of an insulator. They are stacked to form a gapped core leg 1, and a winding 3 is wound around the gapped core leg 1. Upper and lower yoke cores 4.5, which have a rectangular cross section and are constructed by laminating silicon steel plates, are arranged above and below the gapped core leg 1, and the upper and lower yoke cores 4.5 are Board 6
The upper and lower yoke cores 4 and 5, and the gapped core leg 1 are integrally tightened by a tightening stud 7 and a tightening nut 8. 9 is the side leg.

In the present invention, as shown in the enlarged plan view of the block iron core in FIG. There is. In other words, the direction of incidence is the same as that of the fringing magnetic flux 12 leaking from the block core 1a, so that the fringing magnetic flux flows and the iron loss in that portion is reduced.

〔Effect of the invention〕

As described above, according to the present invention, the directionality of the outermost and innermost silicon steel plates of a block core formed by laminating radially stacked grain-oriented silicon steel plates is set at right angles to the direction of the main magnetic flux. Since the fringing magnetic flux is made to flow easily and enter the fringing magnetic flux without difficulty, it is possible to reduce iron loss due to the fringing magnetic flux and obtain an iron core reactor with a gap that achieves even lower loss.

[Brief explanation of the drawing]

FIG. 1 is a front view showing an embodiment of the present invention, and FIG. 2 is an enlarged plan view of the main parts. 1... Core leg with gap, 1a... Block core,
2... Gap, 3... Winding wire, 4.5... Yoke core, 6... Tightening plate, 7... Stud, 8... Tightening nut, 9... Side leg , 11...main magnetic flux, 12...
・Fringing magnetic flux. Applicant's agent Patent attorney Takehiko Suzue

Claims (1)

[Claims] A gapped core leg is constructed by stacking a plurality of block cores with a circular cross section formed by laminating radially cut grain-oriented silicon steel plates through a magnetic gap, and a gapped core leg is constructed by A yoke core with a rectangular cross section formed by laminating silicon steel plates is placed above and below the gapped core legs, and the yoke core and gapped core legs are integrated with a tightening stud. A gap iron core reactor designed to be tightened, characterized in that the direction of punching of the outermost and innermost parts of the block core is perpendicular to the direction in which the main magnetic flux flows.