JPH0817647A - Transformer - Google Patents

Abstract

PURPOSE:To widen the band area by constituting of a series-coupling comprising a ferrite core part and a silicon steel sheet part. CONSTITUTION:A core 1 fitted with a coil 2 is a series-coupled one half part 11 formed of a ferrite with the other half part 2 formed of a silicon steel sheet by butt jointing method. At this time, a proper magnetic gap is made if necessary on the abutted surface through the intermediary of a thin insulating material. In such a constitution, in the application to a high-frequency choke transformer, the ferrite part of the core 1 is compatible with the high frequency to exhibit the proper performances of the high-frequency choke transformer while the silicon sheet part of the core 1 including much of the absolute quantity of the iron part compatible with the low frequency as well as excellently adaptive to a DC component for increasing the apparent capacity as the whole core 1 thereby increasing the saturated current for suppressing the heating in the DC component. Accordingly, the title transformer can be applied to a wide band transformer, thereby enabling the characteristics, design manufacturing performance, etc., to be enhanced.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to reduction of heat generation, expansion of high frequency band, and capacity (usable power) with the same volume.
The present invention relates to a high frequency or industrial / audio frequency wideband transformer capable of increasing the saturation current and the accompanying increase in saturation current.

[0002]

2. Description of the Related Art Conventional high frequency transformers, in particular, high frequency choke transformers include those for smoothing, resonance, noise filters, etc. In all cases, ferrite cores are generally used. Further, the broadband transformer uses a core made of either a silicon steel plate or ferrite, and relies on winding technology to improve the performance.

[0003]

However, the following problems still remain in these high frequency choke transformers and wide band transformers. In the case of a high frequency choke transformer for smoothing, the current flowing through the coil contains ripples in the DC component, but the core is a ferrite core and is not suitable for the DC component (low frequency where the frequency is close to 0). Thing causes an apparent lack of capacity, and therefore
Since it is difficult to increase the saturation current, when the peak value of the ripple current becomes high, its inductance will be lost promptly, and the core is made of a ferrite core, that is, a mixture of iron powder and ceramics. for,
Since the absolute amount of iron powder is small (one of the causes of capacity shortage) and good heat dissipation cannot be obtained, there is a drawback that a considerable amount of heat is generated. In the case of a high frequency choke transformer for resonance and a noise filter, the one using a ferrite core has a drawback that it tends to become unusable due to an abnormal resonance phenomenon in a relatively low high frequency band because of its low self resonance frequency. In the case of a wideband transformer, the winding technology alone cannot provide a sufficient wideband. The present invention is intended to solve these problems.

[0004]

In order to achieve the above-mentioned object, the present invention is a transformer in which a required coil is wound around a core, wherein the core is composed of a ferrite part and a silicon steel plate part connected in series. It is characterized by

[0005]

With the above-described structure, in the application to the high frequency choke transformer, the ferrite portion of the core is suitable for high frequency due to its property, and exhibits the original performance of the high frequency choke transformer, and the core silicon. Due to the nature of the steel plate, the iron part has a large absolute amount, is suitable for low frequencies, and responds well to DC components, increasing the apparent capacity of the core as a whole and increasing the saturation current. Suppresses heating with DC components. Further, the portion made of the silicon steel plate has a high thermal conductivity, and the generated heat is quickly exhausted.
Further, the portion made of the silicon steel plate raises the self-resonance point of the entire core, making it difficult for abnormal resonance to occur in the high frequency band. This characteristic improves the performance of the high frequency choke transformer in particular, but it can also be applied to a wide band transformer. By combining a plurality of cores made of different materials, only a single core material and winding method can be used. We will improve the design of the wideband transformer that was particular about it. That is, a wider band can be realized than using a single core.

[0006]

The drawings show a high frequency choke transformer according to an embodiment of the present invention. In the figure, 1 is a core, 2
Is a coil attached to the core. The core 1 has one half 11 made of ferrite and the other half 12 made of silicon steel plate.
They are made by butting and connecting in series. In addition, an appropriate magnetic gap is formed on the abutting surface by interposing a thin insulating material as required. The dimensions of the core in this case are, for example, about 50 mm in width a, 15 mm in depth b, and 45 mm in height c. When this size was compared with a conventional ferrite core of the same size, the following good results were obtained.

[0007]

[Table 1]

[0008]

[Table 2]

[0009]

[Table 3]

That is, since the capacity is increased, it is possible to extend the saturation range to 160 μH and 45 A, for example, which is conventionally saturated at 160 μH and 20 A, and is stable even with a large peak current. Inductance can be obtained. Further, it can be used for a bridge rectification of a square wave of 20 kHz and 20 A, and it can be operated at a relatively low temperature of about 60 deg, which used to have a temperature increase of 75 deg or more.

[0011]

According to the present invention, since the core is composed of the series connection of the part made of ferrite and the part made of silicon steel plate, even a high frequency choke transformer is suitable for a low frequency by the silicon steel plate and has a DC component. With good parts,
It is possible to increase the apparent capacity of the core as a whole, suppress the heating by the DC component, increase the saturation current, and obtain stable inductance with respect to the peak current. Moreover, since the portion made of the silicon steel plate having a high thermal conductivity can quickly dissipate the generated heat, it is possible to suppress the temperature rise with the same shape as the conventional one even for smoothing. , The efficiency can be improved. Furthermore, even in a high-frequency choke transformer, the self-resonance point of the entire core can be raised by the portion made of the silicon steel plate, and abnormal resonance in the high-frequency band can be made difficult to occur. Even for a filter, its performance can be improved. Other,
Even in the case of a high frequency choke transformer, the reactance value and the extension of its frequency characteristics can be secured in the same volume as that of only the ferrite core, and a ferrite core alone requires a large amount of ferrite cores to increase the capacity. It has excellent effects such as reduction in cost and volume. Also,
Not only high-frequency choke transformers, but as mentioned above, it can be applied to wide-band transformers and can achieve wider bandwidths.
The characteristics, design / manufacturing performance, etc. can be improved.

[Brief description of drawings]

FIG. 1 is a perspective view showing an embodiment of a high frequency choke transformer according to the present invention.

[Explanation of symbols]

1 ... Core 2 ... Coil 11 ... One half made of ferrite 12 ... Another half made of silicon steel plate

Claims (1)

[Claims] 1. A transformer formed by winding a required coil around a core, wherein the core comprises a series connection of a ferrite portion and a silicon steel sheet portion.