JPH01107508A - Transformer - Google Patents

Abstract

PURPOSE: To prevent the generation of a balanced current in a parallel circuit by shifting plural partial windings of both winding parts mutually in reverse directions about the radial direction of a transformer core so that the levels of voltage induced in both the winding parts by a magnetic field are mutually equal. CONSTITUTION: The windings of a transformer connected between terminals A, B are constituted of the 1st winding part having partial widings 1a, 1b and the 2nd winding part having partial windings 2a, 2b. Both the winding parts 1a, 1b and 2a, 2b are connected in parallel and the partial windings 1a, 2b have a large interval from the core K and the partial windings 2a, 1b have a small interval. Halves of the whole number of times of winding of one winding part are respectively distributed to both the partial windings. Namely both the winding parts or wire materials connected in parallel are equivalent about positions in the magnetic field applied by the transformer and voltage levels induced in both the winding parts are made equal. Consequently a balanced current is not allowed to flow into the parallel circuit and a loss due to the balanced current is not generated.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a transformer for, for example, a switching power supply.

Conventional technology A switching power supply mainly used in television receivers, video recorders, etc. isolates the receiver circuit from the power supply in a direct current manner, and on the secondary side, operates voltages of different voltage values and waveforms through a rectifier circuit. Requires a transformer to be supplied. It is known to synchronize switching power supplies with the horizontal frequency of a television receiver. In this case, this switching power supply operates at a frequency of approximately 16 KHz.

When moving to a high-definition television system, there are three
Horizontal frequencies on the order of 2 KHz are used. When switching power supplies operate at this increased frequency, the skin effect becomes more pronounced as a disturbance in the form of higher losses.

This loss must be reduced with higher costs for copper. It is known to use Lindt wire as wire material for windings in order to avoid skin effects. However, slit wires present considerable difficulties in the production of windings by automatic equipment. This is because Lindt wire is less rigid than solid copper wire and is therefore difficult to handle.

Additionally, a larger winding space is required.

In order to avoid skin effects, it is known to form each winding of a plurality of wires connected in parallel, for example as two winding sections or a pie filer winding. In solutions of this type, the two windings or wires necessarily do not have an equal position with respect to the magnetic field of the transformer. This means that the voltages induced in both windings are not completely equal. This induced voltage difference causes a balancing current to flow in the parallel connection of both windings, which results in undesired power losses.

Problems to be Solved by the Invention An object of the present invention is to balance the aforementioned parallel circuit when the winding is composed of a plurality of winding parts or wires connected in parallel in order to eliminate the skin effect. The goal is to prevent current from occurring.

Means for Solving the Problem This problem has been solved by the present invention as set forth in claim 1. ADVANTAGES OF THE INVENTION The solution according to the invention provides the following advantages: both windings or wires connected in parallel are of equal size with respect to their position with respect to the acting magnetic field of the transformer. , so the voltages induced in both windings become equal. When these voltages are equal, no balancing current flows in both windings or in the parallel circuit of the wires, and therefore the voltage induced in both windings becomes equal. The optimum arrangement of the partial windings can be determined empirically, for example, as follows: This parallel circuit is divided into sections, and for a given magnetic field of the transformer, the optimal arrangement of the partial windings is determined empirically. It is determined so that the voltages induced in both are equal.

The invention is particularly advantageous when combined with a single-chamber coil body. In this case, partial windings successive in the axial direction of the coil body are accommodated in individual chambers of the private coil body.

DESCRIPTION OF THE EMBODIMENTS In FIG. 1, the windings of the transformer provided between terminals A and B are divided into a first winding portion having partial windings 1a and 1b, and a first winding portion having partial windings 2a and 2b. It has two winding parts. Both windings 1a, 1b and 2a, 2
1:+ are connected in parallel. Partial windings 1a and 2
b has a large spacing from the core K, and the partial windings 2a and 1b have a small spacing. The total number of turns of a winding section is distributed in half to the two partial windings. As shown, both windings 1a, 1b and 2a, 2b are equivalent with respect to their core K and position relative to the magnetic field. Each winding has one half proximate to the core and the other half remote from the core. Due to their isometric geometrical position relative to the core K, the voltages induced in both windings are also equal. As a result, winding 1 at 1 b,
No balancing current flows in the closed circuit formed by 2 b + 2 a.

In Fig. 2, the first winding section has three partial windings Ia and 1b.
tlC, and the second winding part also has three partial windings 2a,
2b, 2C. The partial windings of both winding sections are also
Since they are staggered with respect to the core as in the figure, they are equivalent with respect to their position with respect to the magnetic field.

One half of the winding 1, namely the partial winding 1b, is located close to the core, and the other half, namely the partial windings 1a and 1c, are arranged far from the core K. Similarly, in the second winding section 2, one half, namely the partial windings 2a and 2c, are provided close to the core, and one half, namely the partial winding 2b, is provided far from the core K.

FIG. 3 shows a corresponding arrangement with five partial windings for each winding section. Winding part 1 has partial windings, wires 1a, lc and 1e, each having one-sixth of the total number of turns of this winding part, i.e. half of the total number of turns is provided far from the core, and in addition each of four of the total number of turns. 1b and 1d with a quarter, ie a quarter of the total number of turns, ie likewise a half, are arranged tightly on the core. Similarly, the partial windings 2b and 2d each have a quarter of the number of turns, i.e. half of the turns are located far from the core, and the partial windings 2a, 2C and 2e each have a sixth of the total number of turns. That is, half of the total number of turns is densely provided on the core. Therefore, both winding sections la, lb.

lc, 1'd, ie and 2a, 2b, 2c.

2d and 2e have equivalent positions relative to the core and the magnetic field.

FIG. 4 shows an embodiment of the private coil body for the primary winding P and the secondary winding S. A total of 11 successive compartments alternately each have a subwinding P of the primary winding and a subwinding S of the secondary winding.

All subwindings P and S are arranged as in FIGS. 1 to 6, ie all subwindings are alternately spaced far and near the core. The primary winding P, which is formed from two winding sections each with six partial windings, has connection terminals A and B. The secondary winding S, which is formed from two winding parts each with five partial windings, has connection terminals C and D. A separate arrangement of primary and secondary windings of this kind in the form of a single-chamber coil body for switching power supplies is known, and is described in German Patent Application No. 312 of the Federal Republic of Germany.
It is detailed in the 9381 publication.

For example, the entire winding is provided in the form of a single-chamber coil, as shown in FIG. This means that axially successive partial windings of the primary winding P and the secondary winding S are accommodated in a plurality of compartments of the compartment coil body. Therefore, in FIG. 4, the vertical lines between the partial turns Hp and S each indicate the partitions forming the cells of the cell coil body.

As mentioned above, a plurality of winding sections 1, 2 connected in parallel each have a plurality of partial windings connected in series.
In a transformer having a winding with On the other hand, in order to implement an arrangement in which the windings are arranged in mutually opposite directions in the radial direction, the axially successive partial windings la, ib of the first coil part are alternately connected to the transformer core. a second radial distance from one to a second radial distance, and further complementary to the partial winding.
It can be provided that the partial windings 2a, 2b of the coil part have the aforementioned second radial distance or first radial distance to the transformer core.

Furthermore, three partial windings 1 are successively arranged in the axial direction of the transformer core.
a-c, 1a-c, for each winding section, both partial windings ia, 1c; 2a, 2c on the terminal side each have a quarter of the total number of turns of one winding section; , furthermore, the intermediate partial windings 1b, 2b can each have a half.

Furthermore, it is possible for partial windings of the winding section that follow each other in the axial direction to be arranged in the individual chambers of the individual chamber coil body.

Effects of the Invention According to the present invention, in a transformer for a switching power supply operated at an increased frequency, in parallel connection of several winding sections in order to reduce the disturbing skin effect, the balance which causes power loss can be improved. A configuration is provided in which no current flows.

[Brief explanation of the drawing]

1 shows the basic construction of the solution according to the invention with two winding sections each having two partial windings; FIG. A configuration diagram of a modified example of the device shown in the figure, Figure 3 is a configuration diagram in which each winding section has five partial windings, and Figure 4 shows the primary winding and secondary winding as private windings. A configuration diagram of the configured winding is shown. 1a, 1b, 1c, ld, le, 2a, 2b. 2C, 2d, 2e... partial winding, P... primary winding,
S... Secondary winding, A, B, C, D... terminal, K...
·core

Claims (1)

[Claims] 1. In a transformer having a winding comprising a plurality of winding parts (1, 2) connected in parallel, each of which has a plurality of partial windings connected in series, the plurality of parts of both winding parts The windings are radially shifted from each other in opposite directions with respect to the transformer core (K) so that the voltages induced in both windings by the magnetic field are substantially equal. Trance.