JPS59110359A - Brushless rotary electric machine - Google Patents

Abstract

PURPOSE:To enable to precisely measure an accurate electric amount in a high sensitivity by securing a coil to the outer periphery of a rotary unit, and forming a member for forming electrodes of a soft magnetic material having high magnetic permeability and low residual magnetization, thereby preventing the residual magnetization. CONSTITUTION:Detecting windings 9, 10 are mounted by mounting a ring 15 on a rotational shaft 14, clamping a coil 16 in which a winding 16b is mounted on an insulating ring 16a in a recess 16a formed on the ring 15 via a bolt 17, and mounting a core 19 for mounting a detector 18 such as a Hall element on the position opposed to the bolt 17. The bolt 17 for clamping the coil 16 is formed of a soft magnetic material having a low residual magnetization, i.e., low residual magnetic flux density such as 75 permalloy (containing 75% of N and 25% of Fe). In this manner, the influence of the residual magnetism of the member can be eliminated, various electric amounts of the rotor can be measured accurately without contact, thereby enhancing the reliability.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a brushless rotor equipped with a non-contact measuring device for measuring voltage, current, etc. on the rotor side.

[Technical background of the invention and its problems]

In a brushless rotating electric machine, for example, a brushless synchronous machine, there are no brushes, slip rings, etc., so electrical quantities such as voltage and current on the rotor side cannot be directly measured from the fixed side. For this reason, the conventional method of measurement was to separately provide a measuring brush and a slip ring.
The advantages of using a brushless system to eliminate the troublesomeness of the original brush were not fully utilized, and there were problems in that the structure was complicated in addition to being difficult to maintain.

Therefore, there is a tendency to determine the electrical volume of the rotor using a non-contact measuring device without using brushes, slip rings, etc. However, devices using magnetism are crude and common. The present applicant has developed a structure for a non-contact measuring device that has such a tendency.
It has already been proposed as No. 891. In other words, a coil that forms a magnetic pole is installed on the outer periphery of the rotating part, a quantity of electricity to be measured is connected to this coil, and the magnetic flux is determined by a detection unit provided on the fixed part side, thereby determining the electricity of the rotating part. The amount can be measured without contact.

However, in such a structure, the coil that generates the FA magnetic flux is fixed to the rotating part with bolts, and the "mild" is fixed to the magnetic poles of the magnetic circuit to withstand centrifugal force.Generally, the bolts are made of steel and are made of highly transparent material. Although it has a high magnetic rate, it has a high residual magnetization.
Once a current is passed through the coil, the magnetization remains even when the current is turned off.

Therefore, in the detection B5, an electric quantity containing an error due to residual magnetization is detected, which requires replacing the bolt and demagnetizing force, and requires extra correction circuit power to correct the measured value. There were drawbacks such as.

[Purpose of misfire]

The present invention has been made in view of the above-mentioned drawbacks, and an object of the present invention is to provide a bra/less rotating electrical machine equipped with a non-contact measuring device that can accurately and highly sensitively determine IJi without generating residual magnetization.

[Summary of the invention]

That is, (1) the bolt that becomes the magnetic pole is made of a soft magnetic material with high magnetic permeability and low residual magnetization; (2) the outer part of the bolt is covered with a soft magnetic material with high magnetic permeability and low residual magnetization to form the magnetic pole; (3) Making bolts of non-magnetic material.

[Embodiments of the invention]

An embodiment of the present invention shown in the drawings will be described below. FIG. 1 shows the first embodiment, in which (1) is a brushless synchronous machine, (2) is the rotation sound β of the brushless synchronous machine (1), and (4) is a brushless synchronous machine.
) is the armature winding of the AC exciter (3), the output of which is connected to the AC input side of the rotary rectifier (5). (6) is a field winding of the brushless synchronous machine (1), which is connected to the DC output side of the rotary rectifier (5) via a shunt (7) to supply excitation force. (9) is a detection winding connected in series with the shunt (7), and (8) is a voltage dividing resistor connected to the other detection winding (l
I is connected in series with the field winding (6) in parallel. The rotating part (2) is composed of the above (41 to uO1). On the fixed side, each detection part Uυ, U is installed facing the detection winding (91, Connected.

Figures 2 and 3 show the measuring device (within the detection winding)
A ring haze is attached to the rotating shaft I, and a winding (16
1 detecting winding (9) in which the iron core Iil is attached to the fixed part, and the detecting element u8, for example, the Hall element, is attached to the position opposite to the coil αQ wound with b) (fixed with lη, bolt ②). , tll winding (16b) K is connected to take out part of the 'fil quantity to be measured, such as field current or voltage. The magnetic flux generated by the coil 4 can be detected non-contact by the detection part 13 (1 Figure 4 shows the detection winding (9), tll, and the pole that fixes the coil 4) [7] is a soft magnetic material with high magnetic permeability and low residual magnetization, that is, low residual magnetic flux density, such as 75 permalloy (75%N125%Fe), mu metal (5%Cu
, 2%Cr, 77%Ni, 16%Fe), supermalloy (5%Mo, 79%Ni, 0.3%Mn, other Fe)
) etc. are used.

Next, the action will be explained. A current flows through the coil aQ of the detection part m (9), forming a magnetic pole and generating magnetic flux, and the detection -〇υ
is detected by the detection element (11). However, since the pole (17) is made of a soft magnetic material, even if current flows through the coil (161 and the voltage aη becomes high magnetic flux density), when the current is cut off, the magnetic flux density becomes almost zero. Again, a measuring device with good reproducibility without the influence of residual magnetization can be obtained.
If the strength of D is insufficient against centrifugal force, there is no need to replace the bolt, and the head of the bolt may be mechanically reinforced by binding with glass fiber impregnated with epoxy resin.

Figure 5 shows the second embodiment, in which a cylindrical sleeve 1 is passed through the bolt a7) and the coil 4 is fixed via the washer υ. ) (17) is a general steel material. sleeve t2
1 mainly forms a magnetic circuit, and POL) (17) mainly fixes the coil and separates the two functions to reduce the influence of residual magnetization. Since the mechanical strength required for the sleeve tel is smaller than that of the first bolt, it may be made of a powdered soft magnetic material compressed and sintered, such as sendust.

FIG. 6 shows the third implementation ψ1j, in which the head (20a) of the sleeve C21jr made of soft magnetic material is enlarged to form four parts (20b) into which the head of the bolt (17) is inserted, and the bolt (20b) made of general mild steel is enlarged. After tightening the coil (16) in step 17), the recess (2b) is closed with a cap +23 made of soft magnetic material. Pol) Q7J is covered with soft magnetic particles, so the influence of residual magnetization of Pol) uil is small.

FIG. 7 shows a fourth embodiment, in which the shape of the sleeve 121 is the same as that of the third embodiment, but the material is a soft magnetic material having high air resistance, such as ferrite (MO/Fe2).
O3:M is a divalent metal ion) is formed by pressure 621 and then sintered, and the coil 111 is made of general mild steel bolt aD.
After tightening the coil (I6), the fourth part (2b) is made of a soft magnetic material and has a high electrical resistance, so the sleeve (201 side) of the coil (I6) is insulated by using a thin insulating sheet (c). In Example 3, the diameter of the shaft becomes thinner and the winding (
The number of turns of 16b) can be increased to increase the magnetic flux.

FIG. 8 shows a fifth embodiment, in which two coils (
(If 0 is installed in parallel and non-magnetic material is fitted, non-magnetic steel bolt α
'0, and the coils αQ are connected to form different polarities to form a detection winding (9). The detection part 0υ on the fixed side is equipped with an iron core for attaching a detection element, such as a Hall element, to form a magnetic path facing the head of the coil (lη). Since current flows in the opposite direction, if the horizontal axis is time and the vertical axis is output as shown in the output characteristic curve diagram in Figure 9, the output curve (to) will be approximately twice as sensitive as the conventional output curve. Since the bolt 17) is a non-magnetic material, it is less susceptible to the effects of residual magnetization, eliminating measurement errors due to residual magnetization, greatly improving reliability.

Although the detection winding (9) and αl have been described above, it is possible to measure not only voltage and current but also various other quantities of electricity. In addition, the coil may be attached directly to the rotating shaft in place of ring u9, and the bolt +17) may be modified in various ways without changing the gist, such as using a hexagonal bolt with a hexagonal hole. I can do it.

〔Effect of the invention〕

As described above, according to the present invention, a coil is fixed to the outer periphery of the rotating part that constitutes a non-contact measuring device in a brushless rotating electric machine, and the JFIJ material that forms the magnetic poles is made free from residual magnetization. The remaining 1'ff (Iff) is eliminated, there is no need to replace parts or demagnetize as in the past, and the electrical 6171 of the rotor can be measured accurately without contact. It has excellent effects such as increasing sex.

[Brief explanation of drawings]

FIG. 1 shows a first embodiment I of the brushless rotating machine of the present invention.
A circuit configuration diagram showing a non-contact measuring device at /lJ,
Figure 2 is a front view showing the 45 structure of the measuring device shown in Figure 1B1, Figure 3 is a vertical cross-sectional view along A-Aal in Figure 2, Figure 4 is a vertical cross-sectional view showing the main parts of the measuring device, FIG. 5 is a longitudinal sectional view showing the main parts of the second embodiment, FIG. 6 is a longitudinal sectional view showing the main parts of the third embodiment, and FIG. 7 is a longitudinal sectional view showing the main parts of the fourth embodiment. 8 is a longitudinal sectional view showing the main parts of the fifth embodiment, and FIG.
The figure is a characteristic curve diagram showing the output per play. 9.10...Detection winding 11.12...Detection section 14
... Rotating shaft 15 ... Ring 16 ... Coil 17 ... Bolt 18 ..., detection element
19... Iron core 20... Sleeve 21...
・Washer 22... Cap 23... Insulating sheet agent Patent attorney Inoue - Male @1 diagram

Claims (1)

[Claims] 1. A non-contact device comprising a member that fixes a coil to the outer periphery of the rotating part to form a magnetic pole, and a detection part that is disposed on the fixed part opposite to this member and measures the magnetic flux caused by the DiJ coil. A brushless rotating electrical machine equipped with a contact-type measuring device, characterized in that the member is made so as not to generate residual magnetization. 2. The brushless rotating electric machine according to claim 1, wherein the member is a bolt made of a soft magnetic material with high magnetic permeability and low residual magnetization. 3. The member is Q'+ ii'F, which is characterized by covering the outside of the bolt with a soft magnetic material with high magnetic permeability and t residual magnetization.
A brushless rotating electrical machine according to claim 1. 4. A brushless rotating electric machine according to claim 2 or 3, characterized in that the soft magnetic material has high electrical resistance. 5. The branless rotating electric machine according to claim 1, wherein the member is a bolt made of a non-magnetic material. 6. A brushless rotating electric machine according to claim 5, characterized in that two coils are arranged in parallel to have magnetic poles of different polarities, and a detection part is opposed to the magnetic poles to form a magnetic circuit. .