JPS63265409A - Interphase reactor - Google Patents

Abstract

PURPOSE:To lighten and miniaturize a reactor core without damaging the function of an interphase reactor by bringing the direction of rolling of grain oriented silicon steel plates laminated at a certain angle with the direction of magnetic flux in the reactor core. CONSTITUTION:In a reactor core 1, grain oriented silicon steel plates are used as one part of the core such as an upper yoke 2 in legs 3 and upper and lower yokes 2, 4 shaped by laminating silicon steel plates, the direction Y of the rolling of the grain oriented silicon steel plates is directed at approximately 90 deg. to the direction of magnetic flux phi in the core, and the legs 3 and a lower yoke 4 in the other core component are composed of non-oriented silicon steel plates. The direction of rolling and the direction of magnetic flux do not coincide in the grain oriented silicon steel plates constituting the core 1, and magnetic flux density is reduced extremely in the same magnetizing force in magnetic characteristics at the time of an angle such as 90 deg.. Since DC magnetic flux density by the unbalance section IDX of DC currents penetrating in a window for the reactor core 1 and mutually flowing in the opposite direction is diminished owing to the magnetic characteristics, AC section magnetic flux density can be increased. Accordingly, the sectional area of the reactor core 1 can be minimized, thus miniaturizing and lightening the reactor core.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to an interphase reactor used in a double star rectifier transformer in which the reactor core is made smaller and lighter.

(Prior Art) Examples of conventional interphase reactors are shown in FIGS. 2 and 3. In the case of FIG. 2, for example, two iron core legs 31 and a yoke 21 magnetically connect the legs. A reactor core 10 is used, and its core legs 31 and yoke 21 are formed by stacking blanks of the same type, for example, non-oriented silicon steel plates. Reactor windings 51 and 52 pass through the window of the reactor core 10, and are used so that direct current IDz*IDs flows in opposite directions. In the case of Figure 3.

A gap 7 is provided in the core leg 31 of the reactor core 11 or a part of the yoke to prevent the reactor core 11 from being magnetically saturated.

(Problems to be Solved by the Invention) FIG. 4 is a diagram of a double star rectifier circuit. Interphase reactor 10
A six-phase rectifier circuit is formed by connecting two three-phase sets of TR, TR, and TR in parallel. This phase reactor 10
An alternating current voltage E having a frequency three times the power supply frequency is applied between the terminals 0, the reactor core 10 is excited by alternating current, and an alternating current magnetic flux Φ^C flows. In addition, although direct current IDm e IDs flows in mutually opposite directions within the window of the interphase reactor core 10, the reactor difference or thyristor element in the two sets of three-phase star connections of the first group TR1 and the second group TR is When used, it is completely 1. due to variations in the firing angle. Yu=ID
*, and the difference IDX = IDt - IO2 causes direct current magnetization, and a direct current magnetic flux Φoc flows in the iron core 10. Note that the DC component magnetic flux density BDC due to the DC magnetic flux ΦDc is determined from the magnetizing force proportional to the DC current ID, depending on the magnetic properties of the iron core.

Therefore, although the composite magnetic flux Φ=Φ^C+ΦDC flows in the iron core, it is necessary to determine the core cross-sectional area (S) so that the reactor core 1o is not magnetically saturated. However, in rectifier transformers generally used for electrochemical industries such as aluminum smelting, since the DC current is large, a large proportion of DC magnetic flux is due to the DC unbalanced current IDX, which is an alternating current magnetic flux density DAC that can be passed through the iron core. can be expressed as BAC = (BS-5DC Todan (here, 83 is the saturation magnetic flux density of the iron core), but this is because the DC component magnetic flux density BDC is large.

It is necessary to reduce the exchange magnetic flux density BAC.

Therefore, there is a drawback that the cross-sectional area S of the reactor core becomes large. For this purpose, the reactor core lO in the rectifier transformer
This has the disadvantage that the total weight and dimensions of the transformer become larger. Also, in order to reduce the above-mentioned noc, there is a method of creating a gap in a part of the iron core as shown in FIG. 3, but this has the disadvantage that the gap deteriorates the rigidity and causes very large vibrations and noise.

An object of the present invention is to provide an interphase reactor in which the reactor core is made smaller and lighter without impairing the function of the interphase reactor.

[Structure of the invention]

(Means for Solving the Problems) The interphase reactor of the present invention uses grain-oriented silicon steel plates for part or all of the core legs or yoke made of laminated silicon steel plates for the reactor core. It is characterized in that the rolling direction of the grain-oriented silicon steel sheet is configured to have an angle that is the direction of magnetic flux within the reactor core.

(Function) In the present invention, since the rolling direction of the grain-oriented silicon steel sheet has an angle with the direction in which magnetic flux flows in the reactor core,
The magnetic permeability in this region becomes extremely small, and the DC magnetic flux generated due to the unbalance of the DC currents flowing in opposite directions can be reduced. Moreover, since there are no gaps in the iron core, rigidity is not compromised.

(Example) The present invention will be explained below with reference to an example shown in FIG.
In the reactor core 1 of the interphase reactor of the present invention,
The core legs 3 and upper and lower yokes 2 and 4 are formed by laminating silicon steel plates, and a grain-oriented silicon steel plate is used for a part of the core, for example, the upper yoke 2, so that the rolling direction Y is equal to the magnetic flux Φ in the core. The other core components, the core legs 3 and the lower yoke 4, are made of non-oriented silicon steel plates.

However, in the grain-oriented silicon steel sheet constituting the reactor core 1 of the interphase reactor of the present invention, when the rolling direction and the magnetic flux direction do not match and have an angle of 9 G'', for example, the magnetic properties are such that the magnetic flux density is Due to this magnetic property, the DC magnetic flux density due to the unbalanced current IDX passing through the window of the reactor core 1 and flowing in mutually opposite directions becomes small, so the AC Therefore, the cross-sectional area of the reactor core 1 can be reduced, making it possible to make the reactor core smaller and lighter.Also, according to the configuration of the present invention, it is not necessary to provide a gap in the reactor core. Since there is no noise, it is also advantageous in terms of vibration and noise characteristics.

In the embodiment shown in FIG. 1, the core leg 3 and the yoke 2 are joined at 45 degrees, but they may be formed by punched plates cut at 90 degrees or at any angle.

〔Effect of the invention〕

As described above, according to the present invention, the DC magnetic flux density component due to the DC unbalanced current in the reactor core becomes smaller and the AC magnetic flux density component can be increased, so the reactor core can be made smaller and lighter. As a result, an economical interphase reactor and a rectifier transformer with an interphase reactor can be obtained.

[Brief explanation of the drawing]

Fig. 1 is a perspective view showing one embodiment of the reactor core of the interphase reactor of the present invention, Figs. 2 and 3 are perspective views of a conventional correlation reactor, and Fig. 4 is a double star rectifier circuit with interphase reactor. FIG. 100...Interphase reactor 1.10.11...Reactor core 2.21...Upper yoke 3.31...Iron core leg 4...Lower yoke 51.52...Reactor winding 6 ... Rectifying element 7 ... Gap Fig. 1 Fig. 2

Claims (2)

[Claims] (1) It is equipped with two reactor windings through which direct current flows in opposite directions, and a reactor core through which these two reactor windings are inserted, and one of the group of laminated silicon steel plates constituting the reactor core. An interphase reactor characterized in that part or all of the grain-oriented silicon steel plates are laminated, and the rolling direction of the grain-oriented silicon steel plates is at a certain angle with the direction of magnetic flux in the reactor core. (2) A grain-oriented silicon steel plate is used for the upper yoke of the frame-shaped reactor core, and the rolling direction thereof is at an angle of about 90° with the direction of the magnetic flux in the core. Interphase reactor according to item 1.