JPS627355A - Field-pole structure of dc machine - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a field pole of a DC machine, particularly to a field pole structure for canceling biased magnetomotive force due to armature reaction.

[Conventional technology]

The field pole structure of a conventional DC machine consists of a field pole iron core part 1a and a field pole piece part 1b, as shown in FIG.
It is usually formed by punching thin silicon steel plates into a shape with two integral parts, stacking them together, and tightening them with rivets.

2 indicates a field winding wound around the field pole iron core 1a. FIG. 5 is a diagram of polarization of magnetic flux due to armature reaction in the case of the field pole structure shown in FIG. 4, where ▪ in the figure indicates the magnetization side of the bias, and ▪ indicates the demagnetization side. In the figure,
IN and Is are the pair of N of the field pole 1 structure shown in FIG.
The field poles of the pole and S pole are shown, and this pair of field poles (N pole) I
Armature winding 7 facing between N and field pole (S pole) Is
When the armature current is passed in the direction shown in the figure, the field pole IN, the yoke 5. In the closed magnetic path formed by the armature core 6, the armature winding 7 causes magnetization or demagnetization, and the magnetization occurs in the counter-armature rotation direction on the magnetic pole surface. In addition, 8 is a commutating pole, 9 shown by a dotted line is a pair of field poles IN, 18. It represents the magnetic flux whose magnetic path is the yoke 5 and the armature core 6.

In order to cancel the biased magnetomotive force caused by such armature reaction, the compensation winding 11 is placed in the slot IO provided in the field pole piece 1b, as shown in FIG. There is also a structure that partially cancels out the magnetomotive force caused by the i-mechanism reaction.

Such a structure requires complicated processing and assembly, and is not generally used, but it is used when the voltage between the commutator pieces is high, when the speed and voltage need to be adjusted over a wide range, when the overload capacity is large, etc. Used in DC machines where armature reaction has a large effect.

[Problem that the invention seeks to solve]

Recent trends in DC machines require smaller size, higher speed, wider speed control, increased overload capacity, etc., and problems include reduced output due to armature reaction and worsened rectification.

As a measure to alleviate this problem, compensation windings and commutating poles as described above are provided, but these structures are complicated and processing and assembly are troublesome.

The present invention was conceived in view of the above-mentioned points,
The purpose is to prevent a decrease in the output of the DC machine due to armature reaction, reduce the number of assembly steps per process, and obtain a highly efficient field pole structure. As a means to solve the problem, the present invention provides a field pole structure with a simple biased magnetic winding, which is different from the conventional compensation winding structure. In order to avoid the influence of magnetism, a hole is made in the center of each of the magnetic pole pieces of a pair of field poles, or a slit is provided to magnetically separate the magnetized side and the demagnetized side due to armature reaction. A technical measure is taken in which a biased magnet winding is wound inside the hole or slit and around the field pole, and the compensation rate for bias magnetization is made variable depending on the number of windings. This structure is designed to cancel out the biased magnetization caused by the winding, thereby preventing an increase in the shape of the field pole, and eliminating the conventional process of processing nine windings into slots for compensating windings.

〔Example〕

Hereinafter, the present invention will be explained based on the embodiment drawings of FIGS. 1 to 3. In the figure, the same or equivalent parts as in FIGS. 4 to 6 are denoted by the same reference numerals. FIG. 1 is a block diagram of one embodiment of the field pole structure of a DC machine according to the present invention, where 3 is a slit and 41° and 42 are biased magnetic windings. 1st
In the figure, a slit 3 that magnetically divides the magnetization side (2) and the demagnetization side (2) of biased magnetization due to armature reaction is provided from the center of the pole piece 1b to the inside of the iron core 1a.
Biased magnetic windings 41 and 42 are provided around the slit 3 and the outer surface of the field pole 1 as shown.

FIG. 2 is a configuration diagram showing another embodiment of the present invention, in which a hole 31 is provided in the center of the pole piece portion 1b through which the biased magnetic windings 41 and 42 are passed. .

In this way, in the present invention, in order to avoid the influence of biased magnetization of the magnetic pole surface due to armature reaction, as shown in FIG. Either a slit 3 is provided to divide the
As shown in the figure, a hole 31 is made in the center of the pole piece of the field pole 1, and biased windings 41 and 42 are wound around the slit 3 or hole 31 and the outer surface of the field pole 1. In addition, the number of turns is 1 turn.

By changing the number of turns, such as two or three turns, it is possible to change the compensation rate for biased magnetism, and the rectifying band can be moved by changing the number of turns depending on the load conditions.

By setting the winding direction on the magnetization side in the demagnetization direction and on the demagnetization side in the magnetization direction, the magnetic flux distribution on the magnetic pole surface of field pole 1 can be obtained close to the conventional compensation winding. .

FIG. 3 is a main magnetic flux diagram of a DC machine having biased magnetic windings according to the present invention, and the figure shows an example of the field pole structure of FIG. 1. As shown in the figure, the magnetic flux 9 whose magnetic path is the pair of field poles IN, Ig, the yoke 5, and the armature core 6 is connected to the biased magnetic winding 41.
, 42, the magnetic flux passes through the magnetic flux path determined by the winding direction of the biased windings 41 and 42, so that the demagnetized side (■) is magnetized and the magnetized side (■) is demagnetized. , the magnetic flux distribution is greatly improved as shown in the figure.

Furthermore, in the biased windings 41 and 42, the winding 41 on the magnetization side (■) and the winding 42 on the demagnetization side (■) are electrically distinguished, and the armature current is applied only to the winding 42 on the demagnetization side (■). If you connect the wires in series, compensation can be made only on the demagnetized side.
It is also possible to prevent a decrease in speed fluctuation rate due to armature reaction, and torque linearity can also be obtained.

Also, although not shown, a biased magnetic winding is wound so that the demagnetized side is on the magnetized side.1. If the wires are connected so that the direction of the armature current flowing through the biased magnetic windings is in a direction in which compensation is possible, compensation can be made only on the demagnetized side.

〔Effect of the invention〕

As described above, according to the present invention, the magnetic flux distribution on the magnetic pole surface is close to that of a conventional compensation winding, and the assembly and processing steps are greatly shortened.

Furthermore, by magnetizing only the winding on the demagnetized side of the biased winding, the magnetic flux density over the entire magnetic pole surface increases, and speed fluctuations and torque fluctuations due to armature reaction are improved.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing one embodiment of the field structure of a DC machine according to the present invention, FIG. 2 is a block diagram showing another embodiment of the present invention,
Figure 3 is a main magnetic flux diagram of a DC machine having a biased magnetic winding according to the present invention, Figure 4 is a diagram showing the field pole structure without a conventional compensation winding, and Figure 5 is the field pole of Figure 4. FIG. 6 is a diagram illustrating a field pole structure with a conventional compensation winding. 1, IN, 18... Field pole, Ia...
Field pole iron core part, 1b... Field pole piece part, 2...
... Field winding, 3... Slit for passing the biased magnetic winding through, 31... Hole for passing the biased magnetic winding through, 41.42... Unbalanced magnetic winding, 5...Yoke, 6...Armature core, 7...Armature winding, 8...Commuting pole, 9... ...Magnetic flux, 10
...Slot, 11...Compensation winding.

Claims (1)

[Claims] 1. A hole is provided in the center of the magnetic pole piece of a pair of field poles, or a slit is provided so as to magnetically divide the magnetized side and the demagnetized side due to armature reaction, and the inside of the hole or slit is 1. A field pole structure for a DC machine, characterized in that a field pole is wound with a biased magnetic winding, and the compensation rate for biased magnetism is made variable depending on the number of turns of the biased magnetic winding. 2. Electrically distinguish the magnetizing side winding and the demagnetizing side winding of the biased winding, and pass the armature current in series only to the demagnetizing side winding determined by the rotation direction of the DC machine. Claim 1 in which compensation is possible only on the demagnetization side.
Field pole structure of the DC machine described in section.