JP2002233119A - Alternator for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an alternator for a vehicle which can reduce the number of conductors used for a stator coil and the number of rectifying elements forming a rectifier. SOLUTION: The alternator 1 for a vehicle comprises a stator 2, in which two sets of stator coils 23, 24 are wound on a stator iron core 22, a rotor 3 provided with a field coil 31, and a rectifier 6 connected to the stator 2. The rectifier 6 includes first rectifying element groups D11, D12, and D13, of which each one end is connected to a positive terminal, second rectifying element groups D14, D15, and D16 of which each one end is connected o a negative terminal and third rectifying element groups Dxu, Dyu, and Dzw connected between these element groups. The stator coils 23 and 24 are connected in series via these third element groups.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle alternator mounted on a passenger car, a truck and the like.

[0002]

2. Description of the Related Art In recent years, there has been a remarkable trend toward higher output and lower noise of automotive alternators, and various technologies have been adopted. In particular, as a technique that is becoming mainstream, a rectangular conductor is used as a stator winding to eliminate mutual interference between coil ends, and two sets of three-phase windings are used for half a wavelength (30 °) of magnetic noise pulsation. Some are wound with a phase difference, and each is connected to a three-phase rectifier. FIG. 13 is a connection diagram of a conventional automotive alternator using two sets of three-phase windings.
For example, Japanese Patent Publication No. 2927288 discloses a vehicle alternator having such a structure. By adopting this technology, it has been confirmed that the high output effect of the close winding of the stator winding and the magnetic sound canceling effect of the double three-phase phase difference winding exhibit unparalleled superior characteristics. I have.

[0003]

By the way, in the above-mentioned conventional AC generator for a vehicle, a large number of rectangular conductors are formed after being superimposed and assembled in a double doping manner. These complicated assembling steps are required, and this is a constraint on cost reduction in terms of the number of parts and the assembling steps.

For this reason, the number of rectangular conductors per slot of the stator can be reduced, the output voltage can be increased with a small number of rectangular conductors, and two independent three-phase windings with less than 12 rectifying elements can be used. There is a demand for a vehicle alternator that can rectify the induced voltage of the vehicle.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has as its object to reduce the number of conductors used for a stator winding and the number of rectifying elements constituting a rectifying device for a vehicle. An alternator is provided.

[0006]

In order to solve the above-mentioned problems, an automotive alternator according to the present invention comprises a rotor having a field winding and a plurality of fixed three-phase winding sets. The stator includes a stator in which a stator winding is wound around a single stator core, and a rectifier for rectifying voltages induced in the plurality of stator windings. They are connected in series. Since the plurality of stator windings are connected in series, it is possible to reduce the electromotive voltage of each stator winding required for generating a predetermined output voltage. Thereby, the number of turns of each stator winding can be reduced, and the number of conductors constituting the stator winding can be reduced.

More specifically, the current flowing through one set of three-phase windings included in the stator winding flows through another set of three-phase windings included in the stator winding. It is desirable that the connection be made in the rectifier. Since the entire output voltage is obtained by combining the electromotive voltages of the three-phase winding sets connected in series, the electromotive voltage generated by each stator winding can be reduced in order to obtain a constant output voltage. .

The rectifying device may further include a first rectifying element group connected to the positive terminal side, a second rectifying element group connected to the negative terminal side, and a first rectifying element group. A plurality of stator windings connected in series, the plurality of stator windings connected in series have a phase difference of 30 ° or 150 ° in electrical angle, and the plurality of stator windings are connected to each other. It is desirable to connect via a third rectifying element group. The phase difference between a plurality of stator windings is set to 30 ° or 1
By setting the angle to 50 °, it is possible to reduce the ineffective component when the voltages are combined in consideration of the phase. Further, by forming a plurality of stator windings with a phase difference corresponding to a half wavelength of magnetic noise pulsation, magnetic noise can be reduced. Further, since the plurality of stator windings are connected to each other via the third rectifier element group, the direction of the current flowing from one stator winding to the other stator winding can be made unidirectional. In addition, it is possible to prevent a current from flowing back between the stator windings.

Further, the plurality of stator windings have an electrical angle of 15
While having a phase difference of 0 °, the third rectifying element group
It is composed of rectifying elements equal in number to the phases of the three-phase winding sets constituting the stator windings, and the corresponding three-phase winding sets of the plurality of stator windings are connected via a single rectifying element. It is desirable to connect. In order to connect a plurality of stator windings, it is only necessary to add rectifying elements for the number of phases of the stator windings, compared to a case where a rectifier corresponding to each of the stator windings is provided. It is possible to reduce the number of rectifying elements used in the vehicle alternator as a whole.

[0010] Further, it is desirable that the above-described stator winding is formed using a plurality of rectangular conductors. By using the rectangular conductor, the space factor in each slot of the stator core can be increased. In addition, when a stator winding is configured using a plurality of rectangular conductors, a forming operation or welding operation for joining the rectangular conductors or drawing out the ends is required. Since the number of turns, that is, the number of rectangular conductors, can be reduced, the labor required for these forming operations, welding operations, and the like can be significantly reduced.

It is preferable that two flat conductors are accommodated in each slot of the stator core. As described above, by connecting a plurality of stator windings in series, the number of turns of each stator winding can be reduced,
Even in the case of using a stator winding in which two rectangular conductors are accommodated per slot, the conventional four-square conductor is used.
An output voltage equivalent to that of an automotive alternator using the rectangular conductor can be obtained.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A vehicle AC generator according to an embodiment of the present invention will be described below in detail with reference to the drawings. [First Embodiment] FIG. 1 is a sectional view showing the overall configuration of an automotive alternator according to a first embodiment. The automotive alternator 1 shown in FIG. 1 includes a stator 2, a rotor 3, frames 4, 5, a rectifier 6, a brush 7, a voltage controller 8,
It is configured to include a rear cover 9 and the like.

The stator 2 includes a stator core 22 and two types of three-phase stator windings 23 and 24 wound at different electrical angles of 30 ° from each other. Details of the stator 2 will be described later. The rotor 3 has a structure in which a field winding 31 in which an insulated copper wire is wound cylindrically and concentrically is sandwiched from both sides through a rotating shaft 33 by pole cores 32 each having a plurality of claws. Have.
Further, a cooling fan 35 for discharging the cooling air sucked from the front side in the axial direction and the radial direction is attached to an end face of the pole core 32 on the front side by welding or the like. Similarly, a cooling fan 36 for discharging the cooling air sucked from the rear side in the radial direction is attached to an end face of the pole core 32 on the rear side by welding or the like. In the vicinity of the rear end of the rotating shaft 33, two slip rings 37, 38 electrically connected to both ends of the field winding 31 are formed. Thus, power is supplied from the brush device 7 to the field winding 31.

The frames 4 and 5 accommodate the stator 2 and the rotor 3. The rotor 3 is supported so as to be rotatable about a rotation shaft 33, and the pole core 32 of the rotor 3 is A stator 2 arranged at a predetermined interval on the outer peripheral side is fixed. These frames 4, 5
Stator winding 2 protruding from the axial end face of stator core 22
Cooling air discharge windows 41, 5
1 and have suction windows 42 and 52 on the axial end surface.

The rectifier 6 includes three-phase stator windings 23, 2
4 for rectifying the three-phase AC voltage generated by the DC motor 4 and generating a DC voltage.
3, 24 are connected in series. Details of the rectifier 6 will be described later. The rear cover 9 is attached so as to cover the rectifying device 6, the brush device 7, and the voltage control device 8 attached to the outside of the frame 5, and protects them from foreign substances.

Vehicle alternator 1 having the above structure
When a rotational force from an engine (not shown) is transmitted to the pulley 20 via a belt or the like, the rotor 3 rotates in a predetermined direction. In this state, by applying an excitation voltage to the field winding 31 of the rotor 3 from the outside, each claw portion of the pole core 32 is excited, and a three-phase AC voltage is generated in the stator windings 23 and 24. A predetermined DC power is taken out from the output terminal 60 of the rectifier 6.

Next, details of the stator 2 and the rectifier 6 will be described. FIG. 2 is a partial cross-sectional view of the stator 2. FIG. 3 is a perspective view of the conductor segment 220 constituting the stator windings 23 and 24. FIG. 4 is a partial perspective view of the stator 2. FIG. 5 is a connection diagram of the vehicle alternator 1 of the present embodiment.

As shown in FIG.
Is an approximately U-shaped rectangular conductor formed by folding a rod-shaped or plate-shaped metal material (for example, copper) at a turn portion 220c, and is an inner layer conductor disposed on the inner peripheral side in the slot 25 from the turn portion 220c. Part 220a and turn part 220
c and an outer conductor portion 220b disposed on the outer peripheral side in the slot 25. Stator winding 23,
As shown in FIG. 4, each of the conductors 24 is formed by inserting the above-described conductor segment 220 into the slot 25 of the stator core 22, and welding and joining the other conductor segment 220 and the end 220d.

By the way, in the vehicle alternator 1 of the present embodiment, as shown in FIG.
And a second stator winding 24 having U, V, and W phases are arranged so as to have a phase difference of 30 ° in electrical angle. The phase difference of 30 electrical degrees corresponds to a slot interval when the slots 25 formed in the stator 22 are viewed in the circumferential direction, as shown in FIG. That is, focusing on two adjacent slots 25, one is used to form the first stator winding 23 and the other is used to form the second stator winding 24. The set of such slots 25 is arranged so as to make a round in the circumferential direction.

Attention is paid to the inner conductor 220a accommodated in one slot 25.
The outer conductor 220b connected to the outer conductor 220b through the turn portion 220c is inserted into the slot 25 separated by one magnetic pole pitch (six slots), and the end 2 on the outer conductor 220b side is inserted.
20d and the end 220d of the other conductor segment 220 on the side of the inner layer conductor portion 220a, which is drawn out of the slot 25 separated therefrom by one pole pitch, are joined. By repeating such joining, an X1-phase partial winding that makes one turn around the stator core 22 is formed. In addition, the outer conductor portion 220b accommodated in the one slot 25 described above.
In the same manner, the X around the stator core 22
A two-phase partial winding is formed. These X1 phase and X2
The two partial windings of the phase are 180 ° out of phase with each other,
The X-phase winding is formed as a whole by connecting the one ends of these partial windings in series with each other with their polarities inverted. The same applies to the other Y, Z, U, V, and W phases.

Further, as shown in FIG. 5, the rectifier 6 of the present embodiment has nine rectifier elements D11 to D11.
16, Dxu, Dyv and Dzw. Three diodes D11, Dxu and D14 are connected in series in this order. In the first series circuit, the output terminal 60 is connected to the cathode of the diode D11, and the anode of the diode D14 is connected to the ground terminal. The diode D
The anode side of 11 and the cathode side of the diode Dxu are connected, and one end of the U-phase winding of the stator winding 24 is connected to this connection point. The anode side of the diode Dxu and the cathode side of the diode D14 are connected,
Further, one end of the X-phase winding of the stator winding 23 is connected to this connection point.

Similarly, three diodes D12, Dyv, D
15 are connected in series in this order. In this second series circuit, the output terminal 6 is connected to the cathode side of the diode D12.
0 is connected, and the anode side of the diode D15 is connected to the ground terminal. The anode side of the diode D12 and the cathode side of the diode Dyv are connected, and one end of the V-phase winding of the stator winding 24 is connected to this connection point. The anode side of the diode Dyv and the cathode side of the diode D15 are connected, and one end of the Y-phase winding of the stator winding 23 is connected to this connection point.

The three diodes D13, Dzw and D16 are connected in series in this order. In the third series circuit, the output terminal 60 is connected to the cathode of the diode D13, and the anode of the diode D16 is connected to the ground terminal. Further, the anode side of the diode D13 and the cathode side of the diode Dzw are connected, and one end of the W-phase winding of the stator winding 24 is connected to this connection point. The anode side of the diode Dzw and the cathode side of the diode D16 are connected, and one end of the Z-phase winding of the stator winding 23 is connected to this connection point.

A first rectifying element group is formed by three diodes D11, D12 and D13 whose one ends are connected to an output terminal 60 as a positive terminal. In addition, three diodes D each having one end connected to a ground terminal as a negative electrode terminal
A second rectifying element group is formed by 14, D15 and D16. Further, a third rectifying element group is formed by three diodes Dxu, Dyv, and Dzw interposed between the first and second rectifying element groups.

The stator winding 23 is Y-connected, and the other ends of the X-phase winding, Y-phase winding, and Z-phase winding are commonly connected to form a neutral point. Similarly, the stator winding 24 is also Y-connected, and has a U-phase winding, a V-phase winding,
The other ends of the Z-phase windings are commonly connected to form a neutral point.

A first stator winding 23 composed of X, Y, and Z phases and a second stator winding 24 composed of U, V, and W phases have an electrical angle of 30 °. The wires are arranged so as to have a phase difference, and the wires are connected in a state where the polarity is inverted. As a result, the X-phase winding and the U-phase winding wound using the adjacent slots 25 have a phase difference of 150 ° in electrical angle. Similarly, each of the Y-phase winding and the V-phase winding and the Z-phase winding and the W-phase winding have a phase difference of 150 ° in electrical angle.

FIG. 6 is a diagram showing the state of the current at the timing when the maximum electromotive voltage is generated in the X-phase winding of the stator winding 23. In FIG. 6, the path through which the current flows is indicated by a dotted line. Rotor 3 is located at the position where the maximum electromotive voltage is generated in the X-phase winding.
The following magnitude of electromotive force is generated in the U-phase winding and V-phase winding when the claw portion is present, and the next smaller electromotive voltage is generated in the Z-phase winding and Y-phase winding. However, it is clear from the vector drawing of the electrical angle distribution of each phase winding that no electromotive voltage is generated in the W phase winding. Therefore, as shown by the dotted line in FIG. 6, the current flows from the X-phase winding to (diode Dxu
U-phase winding → V-phase winding → (external load) → (via diode D15) Y-phase winding or (via diode D16)
It flows in a loop of Z-phase winding → X-phase winding. That is, at this moment, one stator winding 23 composed of the X, Y, and Z phase windings and the other stator winding 24 composed of the U, V, and Z phase windings are connected in series. Power is generated in this state.

Therefore, in the conventional configuration in which two stator windings are connected in parallel as shown in FIG. 13, if the output voltage does not reach the appropriate battery voltage unless four conductors are used per slot, AC generator 1 for vehicle of embodiment
Therefore, even when two conductors are used per slot, an equivalent output voltage can be obtained.

Although the example shown in FIG. 6 focuses on the moment when the maximum electromotive voltage is generated in the X-phase winding, the current flows in series through the two stator windings 23 and 24 at any moment. It is clear that the operation takes place. In such a series operation, the X-phase winding and the U-phase winding are connected so as to have a phase difference of 150 ° close to the opposite phase in electrical angle, a diode Dxu is interposed therebetween, and This is realized only by connecting the cathode side and the anode side of Dxu to a diode D11 corresponding to a positive diode and a diode D14 corresponding to a negative diode of a normal three-phase full-wave rectifier circuit.

FIG. 7 shows a vehicle alternator 1 according to this embodiment.
It is a figure showing the effect at the time of using. In FIG.
“The number of rectangular conductor pieces of the stator” is the number of conductor segments 220 used to configure the stator windings 23 and 24.
The “number of rectifying elements” indicates the number of diodes included in the rectifying device 6, respectively. In the column of “Conventional”, the number of conductor segments and the number of diodes required to configure the automotive alternator shown in FIG. 13 are shown.

As shown in FIG. 7, in the automotive alternator 1 of the present embodiment, the number of conductor segments and the number of diodes can be reduced by 50% and 25%, respectively, as compared with the conventional product, and the number of parts can be reduced. Can be greatly reduced. Also, the stator windings 23 and 24 are arranged so as to have a phase difference of 30 ° in electrical angle, and this angle corresponds to a half wavelength of the magnetic noise pulsation. And magnetic noise can be reduced.

[Second Embodiment] In the above-described first embodiment, the stator 2 is constituted by using the two sets of stator windings 23 and 24 connected in Y. However, the stator connected in Y The winding and the stator winding Δ-connected may be used in combination.

FIG. 8 is a connection diagram of the vehicle alternator according to the second embodiment. FIG. 9 is a perspective view of a conductor segment constituting a stator winding. FIG. 10 is a partial perspective view of the stator of the present embodiment. FIG. 11 is a partial cross-sectional view of the stator of the present embodiment.

As shown in FIG. 11, also in the vehicle alternator 1A of the present embodiment, an X-phase winding included in one stator winding 23A and a U-phase winding included in the other stator winding 24A. The phase windings are accommodated in slots 25 adjacent to each other. However, in the present embodiment, one slot 25 accommodates four conductor segments 230 as rectangular conductors constituting an X-phase winding or the like.

As shown in FIG. 9, the inner end layer conductor 231a in one slot 25 is separated from the outer end layer conductor 231b in the other slot 25 by one magnetic pole pitch in the clockwise direction of the stator core 22. Is paired with. Similarly, the inner middle conductor 232a in one slot 25 is connected to the other slot 2 which is one pole pitch away from the stator core 22 in the clockwise direction.
5 and a pair with the outer middle layer conductor 232b. And
The two conductors forming the pair are connected by using a continuous line on one end face side of the stator core 22 in the axial direction, and passing through the turn portions 231c and 232c.

Therefore, on one end face side of the stator core 22, the outer middle conductor 232b and the inner middle conductor 232
a and the outer end layer conductor 231b and the inner end layer conductor 231a are connected to the continuous line connecting the
A continuous line connected via 31c is included. Thus, on one end face side of the stator core 22, the turn portion 23 as a connection portion of the pair of rectangular conductors is provided.
2c is surrounded by a turn portion 231c as a connection portion of another pair of rectangular conductors housed in the same slot 25.

On the other hand, the inner middle layer conductor 2 in one slot 25
32a is an inner end layer conductor 231 in another slot 25 separated by one magnetic pole pitch in the clockwise direction of the stator core 22.
a is also paired. Similarly, the outer end layer conductor 231b in one slot 25 is also paired with the outer middle layer conductor 232b in the other slot 25 separated by one pole pitch in the clockwise direction of the stator core 22. As shown in FIG. 10, these rectangular conductors are connected by joining on the other end face side in the axial direction of the stator core 22.

In the vehicle alternator 1A of the present embodiment,
X-phase winding and stator winding 24 included in stator winding 23A
A U-phase winding included in A is formed using adjacent slots 25 so as to have a phase difference of 30 ° in electrical angle,
The W-phase winding is connected to the other V-phase winding and the W-phase winding included in the stator winding 24A in a state where the polarity is inverted. The same applies to the other phase windings constituting the stator windings 23A and 24A, and these phase relationships are determined by the respective phases included in the two sets of stator windings 23 and 24 of the first embodiment described above. It becomes the same as the phase relationship of the winding. Therefore, three diodes Dxu, which constitute the second rectifying element group in the rectifying device 6,
By connecting two sets of stator windings 23A and 24A in series via Dyv and Dzw, these two sets of stator windings 2A and 24A are connected in series.
It becomes possible to combine the electromotive voltages of 3A and 24A and take out as an output voltage.

Therefore, similarly to the automotive alternator 1 of the first embodiment, the number of conductor segments constituting the stator windings 23A and 24A and the number of diodes constituting the rectifier 6 are greatly reduced. Can be reduced. Third Embodiment FIG. 12 is a connection diagram of a vehicle alternator 1B according to a third embodiment. The vehicle alternator 1B of the present embodiment is different from the vehicle alternator 1 of the first embodiment.
On the other hand, the stator windings 23 and 24 are
4B in that the rectifier 6 is replaced with a rectifier 6B.

The stator windings 23B and 24B have a phase difference of 30 ° in electrical angle from each other. The two sets of stator windings 23 and 24 used in the first embodiment are physically arranged so as to have a phase difference of 30 ° in electrical angle with each other, and are mutually connected by polarity-inverted connection. 15 in electrical angle
Although formed so as to have a phase difference of 0 °, the two sets of stator windings 23B and 24B of the present embodiment have the same physical arrangement, but are not connected in a polarity-reversed manner. .
Therefore, the electrical angle generated by the physical arrangement is 30 °.
Is directly represented as the entire phase difference.

The rectifier 6B has a configuration in which two sets of full-wave rectifier circuits 61 and 62 are connected in series. The positive terminal side of one full-wave rectifier circuit 61 is connected to the output terminal 60 of the automotive alternator 1B. The other full-wave rectifier circuit 62 has a negative terminal connected to the ground terminal.
Further, the negative terminal side of one full-wave rectifier circuit 61 and the positive terminal side of the other full-wave rectifier circuit 62 are commonly connected. In this way, by separately configuring the two full-wave rectifier circuits 61 and 62 and connecting them in series, it is possible to connect the two sets of stator windings 23B and 24B in series. Therefore, the electromotive voltage of each of the stator windings 23B and 24B required to obtain a constant output voltage can be reduced, and the stator windings 2B and 24B can be reduced as in the case of the first embodiment.
3B, 24B (the conductor segment 23)
0) can be greatly reduced.

It should be noted that the present invention is not limited to the above embodiment, and various modifications can be made within the scope of the present invention. For example, in the above-described third embodiment, the Y-connected 2 having a phase difference of 30 ° in electrical angle is used.
Although the two stator windings 23B and 24B and the rectifier 6B are combined, two sets of the stator windings 23 and 24 used in the first embodiment and two sets of the fixed windings used in the second embodiment are used. The sub windings 23A, 24A and the rectifier 6B may be combined.

Further, in each of the above-described embodiments, the stator winding 23 and the like are formed using a U-shaped rectangular conductor. However, a substantially linear rectangular conductor having no turn portion may be used, The continuous wire used may be wound.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating an overall configuration of a vehicle alternator according to a first embodiment.

FIG. 2 is a partial sectional view of a stator.

FIG. 3 is a perspective view of a conductor segment constituting a stator winding.

FIG. 4 is a partial perspective view of a stator.

FIG. 5 is a connection diagram of the vehicle alternator of the embodiment.

FIG. 6 is a diagram showing a state of a current at a timing when a maximum electromotive voltage is generated in an X-phase winding of a stator winding.

FIG. 7 is a diagram showing an effect when the vehicle alternator of the present embodiment is used.

FIG. 8 is a connection diagram of a vehicle alternator according to a second embodiment.

FIG. 9 is a perspective view of a conductor segment constituting a stator winding.

FIG. 10 is a partial perspective view of the stator according to the embodiment.

FIG. 11 is a partial cross-sectional view of the stator of the present embodiment.

FIG. 12 is a connection diagram of an automotive alternator according to a third embodiment.

FIG. 13 is a connection diagram of a conventional vehicle alternator.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 vehicle alternator 2 stator 3 rotor 4, 5 frame 6 rectifier 7 brush device 22 stator core 23, 24 stator winding

 ──────────────────────────────────────────────────続 き Continued on the front page F-term (reference)

Claims (6)

[Claims] A rotor having a field winding; a stator having a plurality of three-phase winding sets wound around a single stator core; A rectifier for rectifying a voltage induced in the child winding; and a plurality of the stator windings connected in series in the rectifier. 2. The three-phase winding according to claim 1, wherein a current flowing through one set of the three-phase windings included in the stator winding includes another set of the three-phase windings included in the stator winding. An alternator for a vehicle, wherein a connection is made in the rectifier so as to flow to a set. 3. The rectifier according to claim 1, wherein the rectifier includes: a first rectifier element group connected to a positive terminal side; a second rectifier element group connected to a negative terminal side;
A third rectifying element group connected between the first and second rectifying element groups;
The plurality of stator windings connected in series have a phase difference of 30 ° or 150 ° in electrical angle, and the plurality of stator windings are connected to each other by the third winding. An AC generator for a vehicle, wherein the AC generator is connected through a rectifying element group. 4. The stator winding according to claim 3, wherein the plurality of stator windings have a phase difference of 150 ° in electrical angle, and the third rectifying element group includes the three stator windings. It comprises rectifying elements equal in number to the phases of a phase winding set, and the three-phase winding sets corresponding to a plurality of the stator windings are connected via a single rectifying element. AC generator for vehicles. 5. The automotive alternator according to claim 1, wherein the stator winding is configured using a plurality of rectangular conductors. 6. The automotive alternator according to claim 5, wherein two of the rectangular conductors are accommodated in each slot of the stator core.