JP3838146B2 - Cylindrical inductor rotating machine - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention is generally applied to a rotating machine, but is particularly suitable for a vehicle AC generator.
[0002]
[Prior art]
Prior art will be described for an AC generator for a vehicle.
[0003]
Along with an increasing electric load and a decreasing tendency of the engine speed, the generator tends to increase in capacity. Along with this, the burden on the engine has become large. Generally, as a general trend, the generator inertia is proportional to the capacity increase of about 1.6. For example, when the output is doubled, the rotor inertia is tripled.
[0004]
Therefore, the impact on the engine cannot be ignored. For example, rotation and torque fluctuations associated with explosions are inherent in an engine, but if the inertia of the generator is large, there is a problem of increasing the torsional burden on the crankshaft in the case of direct drive without a belt. In the case of a drive generator, a large tension vibration is generated in the belt, so that there is a problem that the vibration is transmitted to a belt sound or other, for example, a hydraulic steering pump. In order to solve this problem, the engine control speed has been increased and the generator pulley has a built-in one-way clutch. In the latter case, the increase in cost due to the complexity of the pulley has been a problem.
[0005]
[Problems to be solved by the invention]
The above-mentioned problem originates in the fact that the inertia of the rotor becomes larger with the conventional extension. Therefore, the problem to be solved by the present invention is to reduce the inertia of the rotor.
[0006]
[Means for Solving the Problems]
First, in the configuration shown in claim 1, a stator core having a three-phase armature winding, an inductor rotor that rotates opposite to the core via a first gap, the rotor, and the rotor A rotating magnetic circuit including a magnetic core for magnetically connecting the stator core via a second gap, wherein the rotor has the first gap on the outer periphery and the second gap on the inner periphery. The magnetic induction passage and the non-magnetic induction passage are formed between the inner periphery and the outer periphery. With this configuration, the above problem is solved as follows. In other words, the rotor has only a cylindrical inductor whose inner and outer peripheries are gap surfaces, so that the inertia is minimized.In particular, the inner and outer diameter portions are connected to each other while the inner and outer diameter portions of the rotor are confined. Since it is configured as a rotor, a robust and lightweight rotor, that is, a thin and low inertia rotor can be obtained.
[0007]
The inductor contains a magnet of the same polarity so that the magnetic flux flows from the center of the rotor to the outside in a slot formed at two magnetic pole pitches. With this configuration, the above problem is solved as follows.
[0008]
In other words, the change in magnetic flux is small with the inductor alone, but the amplitude is approximately doubled by attaching a magnet, and the output is increased. Therefore, under the premise that the same output is sufficient, the rotor can be made small and the rotational inertia is greatly reduced. In this case, the magnet only needs to be fitted into the slot, and a new magnetic circuit configuration that increases the rotor inertia is not required to attach the magnet.
[0009]
Moreover, in the structure shown in Claim 2 , the said field winding is arrange | positioned at the internal diameter side of the said inductor.
[0010]
With this configuration, the above problem is solved as follows. That is, since the average winding diameter of the field coil becomes small, the number of windings can be increased with a low resistance, that is, the same resistance. Therefore, the magnetomotive force of the field winding is large and a high output can be generated. If the same output is sufficient, a small rotor is sufficient, and the inertia can be reduced.
[0011]
In the configuration shown in claim 3 , the field winding is connected in series with at least a part of the DC conversion output of the current of the armature winding or the DC input before AC conversion.
[0012]
With this configuration, the above problem is solved as follows. That is, since the field magnetomotive force is further strengthened, the output increases. If the same output is sufficient, a small rotor is sufficient, and the inertia can be reduced. In the case of a motor, when the internal back electromotive force is low, that is, when tracking is delayed, the difference from the power supply voltage is large, and a large excitation current flows and the output increases. Therefore, the inertia is improved as the total system including the electric mechanical system.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
As a first embodiment, an example in which the cylindrical inductor rotating machine of the present invention is applied to an automotive alternator will be described.
[0014]
FIG. 1 shows the basic structure of a first embodiment of the present invention. A stator core 3 having a three-phase armature winding 2 is fitted and fixed to an inner diameter portion of a front frame 1 made of iron casting. An inductor 4 made of a cylindrical laminated core is disposed inside the stator core 3, and the inductor 4 is fixed to the rotating shaft 6 by a retainer plate 5 at the end face. A rear frame 7 made of a non-magnetic material is fitted and combined with the front frame 1 to surround the stator core 3 and the like.
[0015]
The inductor 4 and the rotary shaft 6 to which the inductor 4 is fixed are rotatably supported by bearings 8 and 9 provided on the front frame 1 and the rear frame 7.
[0016]
A part of the inside of the front frame 1 protrudes in the axial direction and protrudes into the inner diameter portion of the cylindrical inductor 4, and the rotating shaft 6 penetrates through the inner diameter of the front frame 1. 10 is wound.
[0017]
Based on the above description of the basic structure, a more detailed structure will be described.
[0018]
A detailed magnetic circuit structure which is a point of the present application will be described with reference to FIGS. The stator core 3 has six teeth facing inward as shown in FIG. 2, and each has an armature winding wound thereon, and the windings are star-connected as shown in FIG. , Connected to the rectifier 11. The DC output rectified by the rectifier 11 is taken out through the output terminal 12 and connected to the field winding 10 through the field regulator 13.
[0019]
Further, as shown in FIG. 2, the rotor inductor 4 is an inductor 4 having a substantially cylindrical surface on the inner and outer periphery and a slot portion 14 formed in a honeycomb shape on the inner side. The outer periphery and inner peripheral portion of the inductor 4 are connected as the remaining portion of the slot punching, and the width of the inner peripheral connecting portion is smaller than the width of the outer peripheral connecting portion which is narrowed so as not to form a magnetic circuit. Is a part of the magnetic circuit. Magnets 15 having the same polarity are fitted in the slot portion of the inductor 4 at a pitch of two magnetic poles with respect to the rotational circumferential direction.
[0020]
Next, the operation will be described.
[0021]
The rotating shaft 6 driven via a crank pulley, a belt, and a pulley of a vehicle engine (not shown) rotates the inductor rotor 4 via a retainer plate 5. The field regulator 13 is energized so that a direct current flows through the field winding 10 via an output terminal 12 connected to an external storage battery (not shown). As shown in FIG. 1, the field winding 10 forms a field magnetic flux that flows through the stator core 3, the front frame 1, and the inductor 4. Since the inductor 4 is formed with a magnetically well connected portion and a shield portion with respect to the rotation direction, the field magnetic flux fluctuates between the inductor 4 and the stator 3 portion. For this reason, an AC voltage is induced in the armature winding 2 provided on the stator core 3. Further, the inductor 4 is provided with magnets 15 at a two-pole pitch, and this polarity is opposite to the well-connected portion so as to face the stator core 3. The fluctuations and the resulting AC voltage are even greater. The voltage induced in the armature winding 2 is rectified to a direct current and output by the rectifier 11 shown in FIG.
[0022]
As described above, the rotor has only the cylindrical inductor 4 whose inner and outer peripheries are the gap surfaces, so that the inertia is minimized. In particular, the inner and outer diameter portions of the rotor are connected to each other while the inner portion of the cylinder is also overcome. Since the rotor has a truss structure, it is a robust and lightweight rotor, that is, a thin and low inertia rotor. Since the inductor 4 contains the same-polarity magnet in a slot formed with a two-pole pitch, the change in magnetic flux is small with the inductor alone, but the addition of the magnet doubles the amplitude, and the output is increased. growing. Therefore, under the premise that the same output is sufficient, the rotor can be made small and the rotational inertia is greatly reduced. In this case, the magnet only needs to be fitted into the slot, and a new magnetic circuit configuration that increases the rotor inertia is not required to attach the magnet.
[0023]
When the rotational moments of the 100 A class vehicle AC generator actually manufactured by the conventional technology and the generator of the same class according to the present technology were compared, about 28 kgcm ² was reduced to about 1/4, 7 kgcm ² . In other words, if the engine is allowed to be stressed by the same rotational inertia, the capacity can be increased by a factor of four.
[0024]
[Second Embodiment]
Next, a second embodiment is shown in FIGS. Although the belt-driven generator is used in the first embodiment, the example shown here is an application example to a generator with an electric function that is driven directly by the engine. In the first embodiment, the field winding is arranged with a diameter equal to or larger than that of the inductor. However, in the present application, the field winding is arranged in the inner back portion with a diameter smaller than the diameter of the inductor. As a result, the magnetomotive force of the field winding is large and a high output can be generated. If the same output is sufficient, a small rotor is sufficient, and the inertia can be reduced. The width λ of the outer peripheral connecting portion of the inductor is as narrow as the thickness of the laminated iron core, so that a substantial magnetic circuit is not formed, but the width ε of the inner peripheral connecting portion is about 1 of the difference between the inner and outer diameters of the inductor, that is, the band width. / 6 and λ are very large, and the reverse polarity of the magnet plays the role of magnetically connecting to the other non-magnet part, that is, the inductor magnetic path part, as in the first embodiment. However, the inductor band width is narrower than the first embodiment with respect to the rotor diameter.
[0025]
In the first embodiment, the field winding has a split winding configuration, but in the second embodiment, a series winding configuration is different. In this case, that is, the field magnetomotive force is further strengthened, so that the output increases. If the same output is sufficient, a small rotor is sufficient, and the inertia can be reduced. In particular, in the case of a motor, when the internal counter electromotive force is low, for example, when used as a starting motor, large excitation is applied when the internal counter electromotive force is low at a low rotation at the initial stage of starting. In other words, when the follow-up is delayed, there is a large difference between the power supply voltage and a large amount of excitation current flows, so that the output increases. Inertia will be improved.
[0026]
[Third Embodiment]
FIG. 7 shows a third embodiment, which is a combination of the two shown in FIG. That is, a front core 1 made of a magnetic material and a rear frame 7 also made of a magnetic material are fitted with a stator core 3 around which a three-phase armature winding 2 is wound, and inside the stator core. A rotor comprising an inductor 4 fixed to a rotating shaft 6 supported by bearings 8 and 9 via a retainer plate 5 and a permanent magnet 15 fitted in an air core portion of the inductor 4 is disposed. Yes. The front frame 1 and the rear frame 7 extend to the inside of the inductor 4, and an outer diameter portion and an inner diameter portion of the inductor have a gap. Field windings 10a and 10b are wound around the extending portion, and both of them are configured to energize so as to cooperate with each other in an opposing direction to provide a magnetomotive force.
[0027]
The basic operation of the above configuration is the same as that of the first embodiment, except that a field magnetic circuit that faces a single stator core and applies a magnetic flux to the stator core is divided into two parts in the front and rear directions, that is, the inductor. Unlike the configuration of the first embodiment, the field magnetic flux supply section made of a magnetic body frame extending to the inner diameter portion is divided into two parts, so that the magnetic circuit cross section of this field magnetic flux supply path can be reduced, and therefore the inductor The inner diameter of the rotor can be made smaller and the outer diameter can be made smaller, so that the inertia of the rotor can be made smaller than that of the first embodiment. However, it goes without saying that there is a cost disadvantage in that an extra magnetic frame and field winding are required. Therefore, depending on the design purpose, it should be selected whether to adopt a single field magnetic circuit configuration as in the first embodiment or a double field magnetic circuit configuration as in the third embodiment. From the standpoint of reducing inertia, the third embodiment is superior.
[0028]
[Other Embodiments]
In each of the above-described embodiments, the inductor is made of an all-magnetic material, but it is of course possible to make the outer peripheral annular connecting portion nonmagnetic. For example, there is a method in which the entirety is formed of a non-magnetic material SUS and a processing strain is partially applied to make it magnetic SUS. There is also a method of improving rigidity by forming an open slot shape and closing it by welding or the like to form a truss structure.
[0029]
In each of the above embodiments, the slot portion is not fitted with anything, or the magnet is fitted, but the air core portion is fitted with a light, high-strength nonmagnetic material such as aluminum. Thus, the mechanical rigidity can be further increased, and a relatively thin and low inertia rotor can be obtained.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view of an essential part of a first embodiment according to the present invention.
FIG. 2 is a main cross-sectional view of the first embodiment shown in FIG.
FIG. 3 is a circuit diagram of the first embodiment.
FIG. 4 is an explanatory diagram of the main structure of a second embodiment.
FIG. 5 is a cross-sectional view of a rotor according to a second embodiment.
FIG. 6 is a circuit diagram of a second embodiment.
FIG. 7 is an explanatory diagram of the main structure of a third embodiment.
[Explanation of symbols]
1 Front frame 2 Three-phase armature winding 3 Stator core 4 Inductor 5 Retainer plate 6 Rotating shaft 10 Field winding 15 Permanent magnet

Claims (3)

A stator core having a three-phase armature winding, an inductor rotor that rotates opposite to the core through a first gap, and a magnet that connects the rotor and the stator core through a second gap. In a rotating magnetic circuit consisting of a field magnetic circuit that is continuously connected,
The rotor has the first gap on the outer periphery and the second gap on the inner periphery, and forms a magnetic induction passage and a non-magnetic induction passage between the inner periphery and the outer periphery. In addition, the inductor has a slot containing a magnet of the same polarity so that the magnetic flux flows outward from the center of the rotor at a two-pole pitch . The field winding is cylindrical inductor rotating machine as in claim 1, wherein said being disposed on the inner diameter side of the inductor. 2. The field winding according to claim 1, wherein at least a part of the DC conversion output of the current of the armature winding or the DC input before AC conversion is connected in series . The cylindrical inductor rotating machine according to item 2 .

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