JPS6278809A - Reactor - Google Patents

Abstract

PURPOSE:To prevent changes in inductance of windings in operation even when a certain winding is suspended by a method wherein an auxiliary leg core, with which the gap to be used to cope with the state that the current of winding is interrupted, is magnetically shunted, are provided on the iron core equipped with a plurality of windings and gaps opposed to respective windings. CONSTITUTION:A plurality of windings 9 and 9 are wound on the leg 21a of an iron core, and gaps 22 and 22 are provided opposing to respective windings. An auxiliary leg core 23 is provided between the windings 9 and 9 of a leg 21a and also between outer legs 21b and 21b. Accordingly, no magnetic flux is applied to the auxiliary leg core 23 when a current equal to that on both windings is running, and the auxiliary leg core 23 is operated as a reactor in the same manner as conventional. When one of the windings is interrupted, magnetic flux is applied to the auxiliary leg core 23, and almost no magnetic flux is applied to the gap opposing to the interrupted winding. As a result, even when one of windings is interrupted, the inductance of the other windings can be maintained without making almost no reduction.

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention has a plurality of windings and an air gap in the iron core, and even when at least one of the windings is stopped, the inductance of the remaining windings remains constant. Reactor μ where there is very little decrease in
It is related to the structure of

[Conventional technology]

FIG. 9 is a diagram showing a conventional reactor μ disclosed in, for example, Japanese Patent Publication No. 46-87182, and FIG. 11 is a diagram showing an example of the circuit of an electric vehicle using this reactor p. As shown in the figure, the pantograph (2) is moved from the overhead wire (1).
, voltage is applied to the transformer (4) via the circuit breaker (3). A rectifier bridge (
5) The output voltage section of the motor (6)
, and a cutout switch (8).

In addition, in FIG. 9, Qυ is a leg iron (lla) having a plurality of gaps (2) and an outer leg iron (11b) connected to this.
), the magnetic circuit is made up of the iron core, and (9) is this iron core Q.
It is a winding wire wound opposite to the gap (2) of η, and a plurality of wires are used.

Conventional Noriaku)/I/(7) is configured as above,
A voltage is applied to the winding (9) and it is used.

What the reactor core Qυ has in common with the winding (9) is -
The aim is to reduce the number of turns due to an increase in the mutual inductance of 8M (9), as well as to reduce dimensions and weight due to commonality itself.

Here, the number of turns of each winding (9) is N turns, and the iron core is 01.
), the total dimension of each gap (2) is Ig, and the cross-sectional area of the iron core Ql) is 8, then the inductance L0 of each winding (7) can be expressed by the following formula:

Here, μ0: vacuum magnetic permeability.

Actually, due to the magnetic saturation characteristics of the iron core αυ, the inductance Lo decreases as the current increases, and exhibits a characteristic as shown in the curve in FIG. 10(a).

By the way, in the case of this iron core aυ configuration, one of the windings (9) on one side of the winding (9) may fail due to a failure of the electric motor (6).
) is separated from the circuit by the cut-out switch (8), the effective number of turns decreases from 2N turns to N turns, so the inductance L in this case becomes from equation (1), and as shown in Figure 10, (b ) changes into a curve-like characteristic. That is, (1) l (From the comparison of Equation 21, the inductance L with the winding (9) on one side separated is approximately 1/2 of the original inductance Lo (L-#Lo/2)
becomes.

[Problem that the invention seeks to solve]

Since the conventional reactor μ is configured as described above, when at least one of the windings (9) is disconnected,
The inductance of the reactor μ on the current-carrying side decreases, and as a result, the ripple current rate of the circuit current increases, so the electric motor (6
), there were problems such as the possibility of deterioration of rectification.

This invention was made to solve the above-mentioned problems, and aims to provide a reactor in which the inductance of the remaining windings hardly decreases even when at least one of the windings (9) is disconnected. shall be.

[Means for solving problems]

The reactor μ according to the present invention is a supplement that forms a magnetic circuit so that when at least one of the windings in which a magnetic circuit is formed with an iron core having an air gap is electrically cut off, the inductance of the remaining windings does not decrease. A leg iron core is provided on the above iron core.

[Effect]

In this invention, when at least one of the windings is electrically disconnected, the magnetic circuit is changed by the auxiliary core so that the core makes the gap size smaller than the original gap size, thereby reducing the inductance. Reduce crowding.

[Embodiments of the invention]

Examples of the present invention will be described below. FIG. 1 is a block diagram showing an embodiment of the present invention, and (9) is the same as the conventional device. 21) is a geared gear consisting of a leg iron (21a) having a plurality of leg irons and an outer leg iron (21b) connected to both ends of this leg iron (21a) and arranged outside the winding (9). The iron core (to) is an auxiliary leg iron core that connects between the windings (9) of the leg iron (21a) and the outer leg iron (21b).

In the reactor configured as above, during normal operation, the magnetic flux (c) is
is generated by the winding (9) with the same electrical characteristics, and this magnetic flux (
In the auxiliary leg core (E), the polarities of the upper and lower windings (9) are opposite to each other, so they cancel each other out and flow only through the core Qυ. In this case, the inductance is exactly the same as the conventional adhesive (zLz), and is expressed by equation (1), and its characteristics are as shown in the curve in FIG. 2, (a).

Figure 4 is an operational diagram when the lower winding (9) is electrically disconnected. In this case, the magnetic flux (C) is transferred from the leg iron (21a) to the reinforced iron core and the outer leg iron (21b). , flows to the leg iron (21a), and hardly flows to the lower half iron core (al).

This is because the magnetic path resistance is much higher.

Therefore, the inductance L1 in this case becomes L
, =Lo. Therefore, in the case of the above embodiment, even if one side is electrically cut off, there is no reduction in inductance.
FIG. 2 shows characteristics like the curve in (a).

Furthermore, the magnetomotive force (ampere turns) at this time is the winding (
9) is less than V2 when energized, and the cross-sectional area of the supplementary leg core device may be less than 1/2 of the core. Therefore, the increase in weight and dimensions due to the installation of the auxiliary leg iron core can be kept small. In addition, when a plurality of windings (9) are used in this way, and considering that the windings will be electrically cut off due to a failure, etc., the inductance recovery may be reduced by about 10 inches, for example. In some cases, the cross-sectional area of the auxiliary leg core can be further reduced.

FIG. 5 is a diagram showing another embodiment of the present invention, in which the windings (9) are arranged horizontally in parallel. This embodiment also operates in the same way as the above embodiment, and the same effects can be obtained.

FIG. 6 is a diagram showing a still different third embodiment of the present invention, in which four windings (9) are arranged in FIG. Windings arranged in two rows in the horizontal direction, Q]) are two windings arranged in two stages (9
), and consists of a yoke (21a) at a position opposite to the winding (9) and a yoke (21b) connected to both ends of this leg iron (21a) so as to straddle each leg iron (21a). Iron core,■
A two-stage winding (9) is connected between the leg irons (21a) of this iron core (C).
) is connected between supplementary leg core A (28a) and two rows of windings (
9) Connect the yoke on both sides (
This is a cross-shaped auxiliary leg core consisting of auxiliary leg core B (28b) connected to 21b). In this embodiment, during normal operation, the magnetic flux (c) generated in each winding (9) works in an increasing direction and flows to the iron core as in the above embodiment. Next, when one of the windings (9) is electrically shut off, the magnetic flux (C) does not flow into the air gap working part facing that winding (9), but instead flows to the auxiliary leg core ■, so the winding (
9) Operation can be continued without reducing the inductance.

FIG. 7 is a diagram showing a still different fourth embodiment according to the present invention. In FIG. 0, where the arrangement of the windings (9) is concentric with the arrangement of FIG. Line (9
), the yoke as an iron core is placed above and below the winding (9), and (g) is the yoke a! The auxiliary leg core A (Ha) is parallel to D and is located between two rows of windings (9), and is arranged so as to straddle the windings (9) provided in two rows. The auxiliary leg core B (28b) is connected to each yoke Q]) through the auxiliary leg core A (28a) between the windings (9).
This is an auxiliary leg iron core made up of. In this case, the gap) is the yoke Q
1) and auxiliary leg iron core A (28a). This embodiment also functions in the same way as the above embodiment and can bring about the same effects.

FIG. 3 is a configuration diagram showing a further different fifth embodiment of the present invention, in which (9) is a winding wire provided in two stages orthogonally to this, and 21) is a leg surrounding this winding wire (9). An iron core consisting of iron and a yoke, (2) passes through the 0th winding (9), which is an auxiliary leg core located between the windings (9) and connected at both ends to the leg irons of the core (2). There is a gap (2) between Q]) and the foot core).
Under normal operating conditions, the magnetic flux (c) generated in the winding (9) branches to the left and right at the upper yoke of the iron core (2), passes through the left and right leg irons, and is transferred from the lower yoke to the winding (9). Return to However, when the lower side of the winding (9) is electrically cut off, the magnetic flux passes through the leg iron, the auxiliary leg iron core, returns to the winding (9), and flows into the lower half of the leg iron and the lower yoke. This means that the magnetic flux (c) will not flow.

Accordingly, in this embodiment as well, if any of the windings (9) is disconnected, an inductance similar to that in the normal case can be obtained.

In the present invention, although the windings (9) are stacked in two stages as in the above embodiment, the third embodiment, and the fourth and fifth embodiments, the number of stages is A similar effect can be obtained by increasing .

In addition, in this invention, the cross-sectional area S of the auxiliary leg core (E). can be made small with respect to the cross-sectional area S of the iron core (goods). In addition, the inductance recovery rate may be somewhat poor due to winding suspension due to a failure, etc. In such cases, the cross-sectional area So of the auxiliary leg core (E) may be further reduced to make it lighter and more compact. I can do it.

In the above embodiment, a motor circuit has been described, but it goes without saying that the same effect can be obtained even if the circuit is used in other circuits using a plurality of reactors μ.

〔Effect of the invention〕

As explained above, the present invention has the effect that even when at least one of the windings is stopped, the inductance of the remaining windings hardly decreases by providing the auxiliary core in the core having a gap.

[Brief explanation of drawings]

Fig. 1 is a configuration diagram showing one embodiment of the reactor according to the present invention, Fig. 2 is a diagram showing the electrical characteristics of the above embodiment, and Figs. 3 and 4 show normal operation and one winding of the above embodiment. FIG. 5 is a block diagram showing another embodiment of the present invention, FIG. 6 is a block diagram showing a third different embodiment of the present invention, and FIG. 7 is a block diagram showing a third embodiment of the present invention. A further different fourth
Fig. 3 is a block diagram showing a fifth embodiment of the present invention, Fig. 9 is a block diagram showing a conventional reactor, and Fig. 10 shows the electrical characteristics of the conventional reactor. FIG. 11 is a circuit diagram of an electric vehicle as an example of the use of the beam. In the figure, (7) is the reactor μ, (9) is the winding, and 0. (2) is the iron core, 4, @ is the gap, and slope is the auxiliary leg iron core. Note that the same reference numerals in each figure indicate the same or similar parts.

Claims (6)

[Claims] (1) A plurality of windings arranged in a direction in which the magnetic flux generated increases, an iron core having an air gap at a position facing each of the windings and forming a magnetic circuit with the plurality of windings, and the plurality of windings described above. When at least one of the windings is electrically cut off, the inductance of the remaining energized winding is approximately the same as when the plurality of windings are energized. A reactor characterized by comprising an auxiliary leg iron core provided on the iron core so as to do so. (2) The reactor according to claim 1, wherein the iron core has leg irons orthogonal to each winding. (3) The reactor according to claim 1 or 2, wherein all the gaps have the same width. (4) The reactor according to claim 3, wherein all the windings have the same electrical characteristics. (5) The reactor according to claim 1, wherein the iron core is a yoke that is parallel to the winding and provided on both sides of the winding. (6) A reactor according to claim 1, characterized in that a plurality of windings are arranged in a straight line and an iron core is disposed to surround the plurality of windings.