JPS58182807A - Rotary transformer - Google Patents

Abstract

PURPOSE:To raise the efficiency of a rotary transformer equipped with a pole core and a yoke core connecting the pole core by shortening the length of its winding and lessening the resistance of its winding by such an arrangement wherein stator winding is wound around the outer circumference of the yoke core and the length of the outer circumference of the yoke core is made smaller than the outer diameter of a rotor core. CONSTITUTION:A stator is functionally divided into two parts and such a part which is magnetically connected to a rotor core 31 with a small gap provided between them is divided into a core 12 and a core 13 which magnetically connects 2 cores 12 in the axial direction. The pole core 12 is opposed to the rotor core 31 with a gap maintained between them. To make the gap smaller, the outer circumference of the rotor core 31 is circular and the internal surface of the pole core 12 of the stator is circular in construction. Further, the length of the outer circumference of a yoke core 13 connecting pole cores 12 is made smaller than the circumferential length of the outer diameter of the rotor core 31 at least. When an AC current is caused to flow through the winding wound around the outer circumference of the yoke core 13, a magnetic flux flows through a passage like 41 and an AC magnetic flux flows inside the winding of the rotor, and by this, a voltage is induced in the winding of the rotor and electric power is sent to the side of rotor from the stator side.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a rotary transformer, and particularly to a rotary transformer structure suitable for reducing -order loss.

Figure 1 shows the conventional radial gap? It has a rotating transformer structure. In a rotary transformer with a conventional structure,
When using the inner circumferential side as a rotor and the outer circumferential side as a stator, there are the following drawbacks. That is, in the conventional structure, the diameter of the winding frame of the winding wire wound around the outer core must necessarily be larger than the outer diameter of the inner core.

For this reason, the winding wire needs to be long and the winding resistance is high. Therefore, there is a drawback that the efficiency of the rotary transformer is reduced.

The aim of the invention is to eliminate the above-mentioned drawbacks. That is, the aim is to shorten the winding length of the rotary transformer to reduce the winding resistance. The objective is to realize a highly efficient rotating transformer.

The present invention has a structure in which the core of the stator is functionally divided and the diameter of the winding can be reduced.

The present invention will be described below. The rotary transformer to which the present invention is directed is used as shown in the examples shown in FIGS. 2 and 3. Fig. 2 shows an example in which a rotary transformer is used to transmit the excitation power of a generator with claw-shaped magnetic poles. A rotor core 31 of a rotating transformer is attached to the outer periphery of the shaft 5. and rotor winding 32 are attached. This rotating transformer has claw-shaped magnetic poles 7
Rotate to 1 and - body. The voltage induced in the rotor of the rotating transformer is rectified by a commutator attached to the claw-shaped magnetic poles, converted to direct current, and then shunted into a field winding 81 provided on the inner circumference of the claw-shaped magnetic poles 71. . A generator stator (not shown) is provided on the outer periphery of the rotor as shown in FIG.
Generate Seal F:E in the generator.

The frequency of the power supply applied to this rotary transformer is several ten times higher than the commercial frequency by 1'-J, and if a frequency higher than that is used, a small and practical rotary transformer can be obtained. For example, as shown in FIG. 3, a frequency converter 3 converts a DC power source into a high frequency of several KHz or higher. The electric current (E) converted to a higher frequency is
It is added to the stator winding 21 of the rotating transformer. When the stator core 11 of the rotating transformer and the rotor core 31 of the rotating transformer are magnetically coupled, the rotor winding 3 of the rotating transformer
A voltage is induced in 2. In other words, just as power can be sent from the primary side to the secondary side of a transformer, electric power can be sent to the rotor. Primary side of rotating transformer (stator 0IIIl)
By providing a magnetic gap between the power source and the secondary side, power can be transmitted without contact, making it possible to realize a brushless generator as in the case of the generator described above.

Rotating transformers for such applications employ a radial magnetic gap. Therefore, as shown in FIG. 1, the stator coil necessarily has a winding diameter larger than the outer diameter of the rotor core. For this reason, the length of the stator winding becomes particularly long, and the winding resistance becomes large, causing a decrease in the efficiency of the rotary transformer.

In view of the point E mentioned above, the present invention can provide a rotary transformer with low winding resistance.

FIG. 4 shows the entire rotary transformer of the present invention.

The features of the present invention will be explained below.

In FIG. 4, the stator of the present invention is functionally divided into two parts, and a structure suitable for each function is adopted. First, the core 12 of the part to be magnetically coupled to the rotor core 31 through a slight magnetic gap, and the two cores 1
2 and a core 13 that is magnetically coupled in the tube axis direction. Here, the former will be referred to as a magnetic pole core, and the latter will be referred to as a yoke core. That is, the 12 magnetic pole cores face the rotor core 31 with a gap between them. It is necessary to make the magnetic resistance of the magnetic circuit of a rotating transformer as small as possible.
However, it is preferable that the area facing the gap is large. Therefore, in the present invention, gears? In order to have a structure that can be made small, the outer periphery of the rotor core 31 is circular. The magnetic pole core 12 of the stator opposite to the first stator has a circular structure on the inside. Further, the yoke core 13 connecting the magnetic pole cores 12i is dimensioned such that the length of its outer circumference is shorter than at least the outer diameter of the rotor core 31. For example, with respect to D=φ20+on, the outer diameter of the yoke core 13 is set as small as 7tran.

In this core shape, the stator winding is wound around the outer periphery of the yoke core in the present invention. That is, in FIG. 4, the yoke core 13 and the stator winding 21 are connected to the magnetic pole core 12.
However, there are 6 pieces in it.

In such a configuration, when an alternating current is passed through the winding wound around the outer periphery of the yoke core 13, magnetic flux flows through a path 41. That is, the magnetic flux emitted from the yoke core 13 passes through the entire magnetic pole core 12 and enters the rotor core 31 through the gangway. The magnetic flux passing through the inner circumference of the rotor core 31 is
Enter 2 and return to the original York Core VC. At this time, direct pressure is induced in the rotor winding due to alternating current magnetic flux flowing inside the rotor winding, and electric power is sent from the stator inu to the rotor side.

The materials used for the core used in the present invention include a sintered material called a ferrite core, a powdered iron core, a silicon steel plate full S layer core, or an amorphous magnetic material.The winding wire is molded from plastic. Alternatively, the core itself may be coated with an insulating material, such as FBC resin, and then directly wound on the surface of the core itself.

The present invention is characterized in that the stator core is fully functionally divided into two parts, and the stator winding is wound around the outer periphery of the yoke core. Further, the outer circumferential length of the yoke core is selected to be at least shorter than the outer circumferential length of the rotor core. This allows the stator winding to be much shorter than before. Therefore, the winding resistance of the stator winding is small.
This has the effect of reducing the total loss generated in the stator winding.

FIG. 7 shows an example of a wiring diagram when the stator winding is configured with a plurality of stator windings as shown in FIG. 4. In the embodiment shown in FIG. 7, the stator windings wound around the outer periphery of the yoke core 13 are connected in parallel.

Furthermore, as can be seen from the above description, the present invention does not necessarily require the use of six yoke cores as shown in FIG. As an extreme example, it is also possible to configure it with one yoke core as shown in FIG. The dimensions and dimensions of the yoke core are selected arbitrarily within the entire rotating transformer.

Further, the shape of the magnetic pole core can also be made rectangular as shown in FIG. In the case of a rectangular shape, by attaching a yoke core to the corner of the magnetic pole core, a relatively small-sized rotating transformer can be realized.

8 and 9 are modified examples of FIG. 5, in which the magnetic poles are fan-shaped. In the case shown in the figure, there is an advantage that the stator core of the rotary transformer can be assembled from a radial position.

As described above, in the present invention, the stator core? It is functionally divided into two parts, each shaped to suit its purpose. One of them is the rotor core and a slight magnetic gigang?
Is this a magnetic pole core with a slightly larger diameter than the rotor core in order to reduce the magnetic resistance of the whole car? A core 12i having a curved surface is used, and this core is divided into a yoke core 13 that is coupled in the axial direction. The outer circumference of the core 13 is configured to be shorter than the circumference of the outer diameter portion of the rotor core 31. This has the effect of shortening the length of the winding and reducing the winding resistance.

This has the effect of reducing loss and realizing a highly efficient rotating transformer.

[Brief explanation of drawings]

FIG. 1 is a sketch of a conventional rotary transformer, and FIG. 2 is a longitudinal sectional view of a generator with claw-shaped magnetic poles. FIG. 3 is a circuit diagram of a circuit that fully utilizes a rotating transformer. FIG. 4 is a longitudinal section and a front view of the rotary transformer of the present invention. FIG. 5 is a 9th diagram of a modified example of the rotary transformer of the present invention. Figure 6 is a sketch of the magnetic pole core. FIG. 7 is a wiring diagram when the stator winding is composed of a plurality of stator windings. Figure 8 is a sketch of a rotating transformer with a fan-shaped magnetic pole core. FIG. 9 is a front view and a longitudinal sectional view of a rotary transformer having fan-shaped magnetic poles. DESCRIPTION OF SYMBOLS 1... Rotating transformer, 2... Power supply, 3... High frequency converter, 4... Rectifier, 5... Load, 11... Conventional stator core, 12... Magnetic pole core, 13... Yoke core, 21... Stator winding, 22... Winding frame for stator winding, 31... Rotor core, 32... Rotor winding, 33... Rotor Winding errands / Ro Figure 2, 32 Figure 3 Ma Figure 4 Ro Figure S Figure 6 Country $7

Claims (1)

[Claims] 1. A stator core and a stator winding having a rotor core and a rotor winding wound around the rotor, and supplying all of the magnetic flux to the rotor core through gear distribution 1. A rotary transformer with a radial gap that sends electric current from the stator winding to the rotor winding, the inner periphery of which has a circular or semicircular curved surface, and a diameter slightly larger than the rotor core. A magnetic pole core having an inner circumferential curved surface and a yoke core connecting the magnetic pole cores, an identifier winding is wound around the outer periphery of the yoke core, and the outer circumference length of the yoke core is at least smaller than the outer diameter of the rotor core. Rotating transformer with all features.