Motor and control unit thereof

• US 20090236930A1
• Filed: 04/27/2006
• Published: 09/24/2009
• Est. Priority Date: 04/28/2005
• Status: Active Grant

• Current Assignee: DENSO Corporation
• Original Assignee: DENSO Corporation
• Inventors: Nashiki, Masayuki
• Granted Patent: US 7,816,822 B2
• Time in Patent Office: Days
• US Class Current: 310/257
• CPC Class Codes: H02K 1/145 having an annular coil, e.g. of the claw-pole type
• CPC Class Codes: H02K 1/246 Variable reluctance rotors
• CPC Class Codes: H02K 1/2766 having a flux concentration effect
• CPC Class Codes: H02K 1/2773 consisting of tangentially magnetized radial magnets
• CPC Class Codes: H02K 21/145 having an annular armature coil with homopolar co-operation H02K21/20
• CPC Class Codes: H02K 21/16 having annular armature cores with salient poles with homopolar co-operation H02K21/20
• CPC Class Codes: H02K 21/227 having an annular armature coil
• CPC Class Codes: H02K 21/24 with magnets axially facing the armatures, e.g. hub-type cycle dynamos
• CPC Class Codes: H02K 3/28 Layout of windings or of connections between windings windings for pole-changing H02K17/06, H02K17/14, H02K19/12, H02K19/32

Abstract

A motor includes: a rotor having permanent magnets in which N-poles and S-poles are alternately arranged in the circumferential direction; seven stator pole groups, each of which has a plurality of stator poles arranged in the circumferential direction, the stator pole groups being arranged with the circumferential and axial positions of the stator poles in one stator pole group being offset from those of other stator pole groups; and a plurality of loop windings formed in the circumferential direction and arranged at positions adjacent to the plurality of stator pole groups in the rotor shaft direction.

Claims

1. A motor, comprising:

a rotor having rotor pole groups, in which N-poles and S-poles are alternately arranged in the circumferential direction and;

an (N+1) number of stator pole groups, in which a plurality of stator poles are arranged for each phase along or around the circumference so as to be positioned at substantially the same rotational phase position in terms of electrical angle; and

a 2N number of loop windings axially arranged between the stator pole groups of individual phases, with the same phase loop windings being arranged at axial ends.

2. The motor according to claim 1, wherein:

the (N+1) number of stator pole groups are arranged so that an electrical angular position is sequentially changed.

3. The motor according to claim 1, wherein:

the (N+1) number of stator pole groups are arranged so that the stator pole groups corresponding to two phases having an electrical angle difference of about 180°

are adjacent to each other.

4. The motor according to claim 3, wherein:

with the stator pole groups corresponding to two phases having an electrical angle difference of about 180°

as being one set, the (N+1) number of stator pole groups are arranged so that adjacently positioned stator pole groups, each of which belongs to one of two adjacent sets, have a minimum phase difference in electrical angle.

5. The motor according to claim 1, wherein:

the (N+1) number of stator poles are arranged so that a sum of widths of the two stator poles positioned at both ends in the rotor shaft direction in a plane opposed to the rotor, is equal to a width of each of other stator poles in the rotor shaft direction in the plane opposed to the rotor.

9. The motor according to claim 1, wherein:

areas of the stator poles in a plane opposed to the rotor are in a sinusoidal distribution or analogous to sinusoidal distribution in the circumferential direction of the rotor.

10. The motor according to claim 1, wherein:

a width of the stator poles in the rotor shaft direction in the plane opposed to the rotor is larger than an interval between the stator poles adjacently positioned in the rotor shaft direction.

11. The motor according to claim 1, wherein:

where, for a group of optional X-phase stator poles, a sum total of magnetic fluxes that pass through the stator poles is Φ

x, a rotation change rate of each magnetic flux Φ

x is dΦ

x/dθ

, a magnetomotive force or a winding current that works on an air gap portion between each stator pole and each rotor pole is Ix, a number of turns of a winding is WTx, and a generated torque component that is a product calculated from dΦ

x/dθ

×

Ix×

WTx is Tx; and

where, for another group of optional Y-phase stator poles, a sum total of magnetic fluxes that pass through the stator poles is Φ

y, a rotation change rate of each magnetic flux Φ

y is dΦ

y/dθ

, a magnetomotive force or a winding current that works on an air gap portion between each stator pole and each rotor pole is Iy, a number of turns of a winding is WTy, and a generated torque component that is a product calculated from dΦ

y/dθ

×

Iy×

WTy is Ty,

two or more among the magnetic fluxes Φ

x and Φ

y, the winding currents Ix and Iy, and the numbers of turns of winding WTx and WTy, which are determined by a mutually facing area between the stator poles and the rotor poles, have different values between the X-phase stator poles and the Y-phase stator poles, and the generated torque components Tx and Ty of the respective stator poles are equal.

12. The motor according to claim 1, wherein:

the stator poles of each phase are divided into K number of stator poles in the rotor shaft direction; and

the K number of stator poles of individual phases are provided with K number of loop windings in the rotor shaft direction so that the loop windings of the same phase are disposed on one side or both sides of each of the K number of stator poles.

13. The motor according to claim 1, wherein:

a plurality of loop windings for passing different phase currents are wound about a slot formed between the stator poles adjacently positioned in the rotor shaft direction to obtain a combined current; and

the number of turns of each of the plurality of loop windings wound about the slot is determined so that a sum total of products, each of which is obtained by multiplying a current vector passing through each winding with the number of turns of each winding, equals to a vector of the combined current.

14. The motor according to claim 1, wherein:

in a wire connection between the loop windings, the loop windings having the same phase in terms of electrical angle are connected in series and the loop windings having different phases of about 180°

in terms of electrical angle are oppositely connected in series.

19. The motor according to claim 1, wherein:

the loop windings, each of which the same current is passed through, are connected in series, with the directions of the currents being matched with each other, to obtain a star connection with the individual serially connected windings or with single windings.

24. The motor according to claim 1, wherein the motor comprises:

a rotor having rotor pole groups, in which N-poles and S-poles are alternately arranged in the circumferential direction; and

an N number of stator pole groups, in which a plurality of stator poles are arranged for each phase along or around the circumference so as to be positioned at substantially the same rotational phase position in terms of electrical angle, where N is an even number, wherein;

an N/2 number of stator pole groups are arranged in a phase of an integral multiple of 360°

/N in electrical angle; and

another N/2 number of stator pole groups are arranged in a phase different from the phase of an integral multiple of 360°

/N in electrical angle.

27. The motor according to claim 3, wherein:

among the stator pole groups, those for two phases having an electrical angle difference of about 180°

are arranged so as to be adjacent to each other;

back yoke portions of the stator pole groups for two phases, which are mutually different by about 180°

, are electromagnetically connected through a soft magnetic material;

back yoke portions of rotor pole groups opposed to the stator pole groups for two phases having an electrical angle difference of about 180°

, are also mutually electromagnetically connected through a soft magnetic material; and

at least one of a space made between a pair of the stator pole groups for two phases having a difference by 180°

, and another adjacent pair of the stator poles, and a space made between two pairs of rotor pole groups which are opposed to these stator pole groups, is vacant or provided with a nonmagnetic material for electromagnetic separation.

28. The motor according to claim 27, wherein:

the space between the two pairs of the rotor pole groups opposed to the pair of the stator pole groups for two phases having a difference of 180° and

another adjacent pair of the stator poles, is vacant or provided with a nonmagnetic material for electromagnetic separation; and

among the four stator pole groups constituting of the two pairs, each of which has a mutual phase difference of 180°

, magnetic paths extending from individual tooth ends of central two stator pole groups to the back yoke portions are partially closely overlapped with each other or shared.

32. The motor according to any of claim 1, wherein:

the stator poles and the windings of the individual phases are replaced in the rotor shaft direction, or the order of the phases in the rotor shaft direction is sequentially shifted in the rotor shaft direction according to a rotation angle.

33. The motor according to claim 1, wherein:

as a concrete configuration of the loop windings, the loop windings are arranged in an irregular manner reflecting a shape of each stator pole.

34. The motor according to claim 1, wherein:

each winding is made up of a flat wire.

35. The motor according to claim 1, wherein:

where a length of an N-phased motor core in the rotor shaft direction is MT, a length of a magnetic path in the rotor shaft direction, extending from a tip end of each stator pole to the back yoke of the stator is made larger than MT/N.

36. The motor according to claim 1, wherein:

the rotor is partially provided with permanent magnets at a surface or an inside thereof, with at least a portion of the surface being made of a soft magnetic material.

37. A motor according to claim 1, wherein:

the rotor is provided with a plurality of narrow gaps or nonmagnetic materials or permanent magnets, each of which extends from one rotor pole to another rotor pole.

38. The motor according to claim 1, wherein the motor comprises:

a rotor where each rotor pole is structured by a stack of electromagnetic steel plates, each of which is bent toward poles of the rotor, the rotor pole being arranged substantially parallel to the rotor shaft.

39. The motor according to claim 37, wherein:

each electromagnetic steel plate arranged substantially parallel to the rotor shaft is provided with a permanent magnet on one side or on both sides thereof.

40. The motor according to claim 1, wherein:

the rotor is circumferentially provided with salient poles made of magnetically soft magnetic material.

41. The motor according to claim 1, wherein:

the rotor is provided with windings to which induced currents can be supplied.

43. The motor according to claim 1, wherein:

the stator poles are arranged on an inner-diameter side and the rotor is arranged on an outer-diameter side.

44. The motor according to claim 1, wherein:

the stator poles and the rotor are relatively axially arranged.

45. A motor wherein the motor is configured by incorporating and combining two or more motors including the motors recited in claim 1.

46. The motor according to claim 1, wherein:

at least a portion of the rotor in the plane opposed to the stator poles is made of a soft magnetic material, with the rotor being provided, at a surface or an inside thereof, with permeable magnetic paths of soft magnetic material, for guiding magnetic fluxes in the rotor shaft direction or in the radial direction.

47. The motor according to claim 1, wherein:

at least a portion of the rotor in the plane opposed to the stator poles is made of a soft magnetic material, with the rotor being provided inside thereof with gap portions or nonmagnetic material portions for limiting rotation direction freedom of magnetic fluxes.

48. The motor according to claim 1, wherein:

a portion of the regularly arranged stator poles or a portion of the regularly arranged rotor poles is removed.

49. The motor according to claim 1, wherein:

the number of the phases is set as being Sn, the number of pairs of the poles is set as being Pn, and the number of the poles is set as being 2×

Pn; and

a portion of the stator poles are removed from a configuration where the number of the stator poles is Sn×

Pn.

50. The motor according to claim 1, wherein:

a plurality of the stator poles of each of the N number of stator pole groups in the stator are divided into “

n”

sets, while circumferential positions of the stator poles belonging to each set are relatively displaced by an integral multiple of 360°

/(m×

n) in electrical angle, where “

m”

is an order of torque ripple to be reduced.

51. The motor according to claim 1, wherein:

a plurality of the rotor poles are divided into “

n”

sets, while circumferential positions of the rotor poles belonging to each set are relatively displaced by an integral multiple of 360°

/(m×

n) in electrical angle, where “

m”

is an order of torque ripple to be reduced.

52. The motor according to claim 1, wherein:

each of the salient stator poles and each of the salient rotor poles, which are closely opposed to each other, have a concavo-convex shape to provide a configuration having a large facing area.

53. The motor according to claim 1, characterized in that the motor has a structure in which:

the stator and the rotor are arranged being opposed to each other, the rotor being provided with recessed and projected portions in the rotor shaft direction, all or portion of the windings of the stator being located in the recessed portions of the rotor.

54. The motor according to claim 1, wherein:

a portion or all of the windings of the motor are made up of metal pipes; and

the metal pipes serving as conductors are provided with a cooling mechanism with a structure for passing liquid or gas.

6. A motor, comprising:

a rotor having rotor pole groups, in which N-poles and S-poles are alternately arranged in the circumferential direction;

an N number of stator pole groups, in which a plurality of stator poles are arranged for each phase along or around the circumference so as to be positioned at substantially the same rotational phase position in terms of electrical angle; and

a 2N number of loop windings axially arranged at both sides of each of the stator pole groups of individual phases, with the same phase loop windings being arranged at axial ends.

7. The motor according to claim 6, wherein:

a plurality of the loop windings arranged in a slot formed by the two stator poles adjacent to each other in the rotor shaft direction are combined into a single loop winding.

8. The motor according to claim 6, wherein:

the loop winding which is arranged outside the two stator poles at both ends along the rotor shaft direction is removed.

15. A motor, comprising:

a rotor having rotor pole groups, in which N-poles and S-poles are alternately arranged in the circumferential direction;

a P number of stator pole groups, in which a plurality of stator poles are arranged for each phase along or around the circumference so as to be positioned at substantially the same rotational phase position in terms of electrical angle; and

a Q number of loop windings axially arranged between the stator pole groups of individual phases, wherein;

input lines for motor are provided so that currents can be individually supplied to each of the Q number of loop windings (provided that Q=2n for P=(N+1), Q=2(N−

1) for P=N, Q=N for P=(N+1), or Q=(N−

1) for P=N, where N is a positive integer of “

3”

or more).

42. The motor according to claim 15, wherein:

areas of the stator poles in a plane opposed to the rotor are in a sinusoidal distribution or analogous to sinusoidal distribution in the circumferential direction, with a relationship Nss=3×

Pn, where Pn is the number of pole pairs and Nss is the number of the stator poles, being satisfied in case the stator poles of three phases are provided.

16. A motor, comprising:

a rotor having rotor pole groups, in which N-poles and S-poles are alternately arranged in the circumferential direction;

a P number of stator pole groups, in which a plurality of stator poles are arranged for each phase along or around the circumference so as to be positioned at substantially the same rotational phase position in terms of electrical angle; and

a Q number of loop windings axially arranged between the stator pole groups of individual phases, wherein;

the same currents are reversely passed through two windings of the Q number of loop windings, the two windings being arranged sandwiching two or more stator pole groups (provided that Q=2N for P=(N+1), or Q=2(N−

1) for P=N, where N is a positive inter of “

3”

or more).

17. The motor according to claim 16 wherein:

the two windings, in which the same currents are reversely passed through, are oppositely connected in series.

55. A motor and a control unit therefor, wherein:

the control unit comprises;

an N-phased motor recited in claim 16; and

an N number of voltage-variable units VVU, in each of which two electrical power elements TR capable of on-off control of current are directly or indirectly connected in series to power source terminals VP and VN,

an N number of terminals of star-connected windings, or an N number of terminals at connecting portions of delta-connected windings in the N-phased motor, are connected to the N number of voltage-variable units VVU to control voltages and currents.

18. A motor, comprising:

a rotor having rotor pole groups, in which N-poles and S-poles are alternately arranged in the circumferential direction;

a P number of stator pole groups, in which a plurality of stator poles are arranged for each phase along or around the circumference so as to be positioned at substantially the same rotational phase position in terms of electrical angle; and

a Q number of loop windings axially arranged between the stator pole groups of individual phases (provided that Q=N for P=(N+1), or Q=(N−

1) for P=N, where N is a positive inter of “

3”

or more).

56. A motor and a control unit therefor wherein:

the control unit comprises;

an N-phased motor recited in claim 18; and

an N number of voltage-variable units VVU, in each of which two electrical power elements TR capable of on-off control of current are directly or indirectly connected in series to power source terminals VP and VN,

an N number of terminals of star-connected windings, or an N number of terminals at connecting portions of delta-connected windings in the N-phased motor, are connected to the N number of voltage-variable units VVU to control voltages and currents.

57. A motor and a control unit therefor, wherein:

the control unit comprises;

an N-phased motor recited in claim 18; and

an N number of voltage-variable units VVU, in each of which two electrical power elements TR capable of on-off control of current are directly or indirectly connected in series to power source terminals VP and VN,

an N number of terminals of star-connected windings, which number is a sum of an (N−

1) number of terminals of the star-connected windings and a center point NN of the star-connected windings, or an N number of terminals of delta-connected windings, which number is a sum of an (N−

2) number of terminals at connecting portions of an (N−

1) number of delta-connected windings and two terminals of a portion at which an N^th winding is to be arranged in the N-phased motor, are connected to the N number of voltage-variable units VVU to control voltages and currents.

20. A motor, comprising:

a rotor having rotor pole groups, in which N-poles and S-poles are alternately arranged in the circumferential direction;

an (N+1) number of stator pole groups, in which a plurality of stator poles are arranged for each phase along or around the circumference so as to be positioned at substantially the same rotational phase position in terms of electrical angle; and

an N number of loop windings axially arranged between the stator pole groups of individual phases, wherein;

the N number of windings are in star connection.

21. A motor, comprising:

a rotor having rotor pole groups, in which N-poles and S-poles are alternately arranged in the circumferential direction;

an N number of stator pole groups, in which a plurality of stator poles are arranged for each phase along or around the circumference so as to be positioned at substantially the same rotational phase position in terms of electrical angle; and

an (N−

1) number of loop windings axially arranged between the stator pole groups of individual phases, wherein;

the (N−

1) number of windings are in star connection; and

an N number of input lines are provided, the N number of lines including a center connection portion of the star connection, which portion serves as a motor input.

22. A motor, comprising:

a rotor having rotor pole groups, in which N-poles and S-poles are alternately arranged in the circumferential direction; and

four stator pole groups, in which a plurality of stator poles are arranged for each phase along or around the circumference so as to be positioned at substantially the same rotational phase position in terms of electrical angle, wherein;

a loop winding having an Nw number of turns is arranged at an inner side of each of stator pole groups arranged at both ends;

two loop windings, each of which has an Nw/2 number of turns, are arranged between two central stator pole groups; and

the four windings are in star connection.

23. A motor, comprising:

a rotor having rotor pole groups, in which N-poles and S-poles are alternately arranged in the circumferential direction; and

four stator pole groups, in which a plurality of stator poles are arranged for each phase along or around the circumference so as to be positioned at substantially the same rotational phase position in terms of electrical angle, wherein;

a loop winding having an Nw number of turns is arranged at an inner side of each of stator pole groups arranged at both ends;

a loop winding having an Nw/2 number of turns is arranged between two central stator pole groups; and

the three windings are in star connection.

25. A motor, comprising:

a rotor having rotor pole groups, in which N-poles and S-poles are alternately arranged in the circumferential direction; and

an (N+1) number of stator pole groups, in which a plurality of stator poles are arranged for each phase along or around the circumference so as to be positioned at substantially the same rotational phase position in terms of electrical angle, wherein;

among the stator pole groups, those which correspond to two phases having an electrical angle difference of about 180°

are arranged so as to be adjacent to each other; and

an N number of loop windings are arranged between the stator pole groups of individual phases.

26. The motor according to claim 25, wherein:

two stator pole groups at both ends in the rotor shaft direction are arranged on one side being adjacent to each other to provide a single stator pole group.

29. A motor, comprising:

a rotor having rotor pole groups, in which N-poles and S-poles are alternately arranged in the circumferential direction; and

an N number of stator pole groups, in which a plurality of stator poles are arranged for each phase along or around the circumference so as to be positioned at substantially the same rotational phase position in terms of electrical angle, wherein;

the N number of stator pole groups are alternately arranged in the order of phases in terms of electrical angle; and

loop windings are arranged in respective spaces between the stator pole groups of individual phases.

30. A motor having six stator pole groups, the motor, comprising:

a first configuration made up of stator pole groups of first, third and fifth phases in terms of electrical angle, and a second configuration made up of stator pole groups of a second, fourth and sixth phases in terms of electrical angle, are arrange in the rotor shaft direction;

loop windings are arranged between the stator pole groups of the first, third and fifth phases;

loop windings are arranged between the stator pole groups of the second, sixth and fourth phases;

rotor poles are arranged opposed to the stator pole groups; and

at least one of a space between the first configuration and the second configuration, or a space between the two pairs of rotor pole groups opposed to the stator pole groups, is vacant or provided with a nonmagnetic material for electromagnetic separation.

31. A motor, comprising:

a rotor having rotor pole groups, in which N-poles and S-poles are alternately arranged in the circumferential direction; and

an N number of stator pole groups, in which a plurality of stator poles are arranged for each phase along or around the circumference so as to be positioned at substantially the same rotational phase position in terms of electrical angle, wherein;

the N number of stator pole groups are arranged in the order of phases in terms of electrical angle with two phases being skipped inbetween; and

loop windings are arranged in respective spaces between the stator pole groups of individual phases.

58. A motor and a control unit therefor, wherein:

the control unit comprises;

a motor, comprising;

a rotor having rotor pole groups, in which N-poles and S-poles are alternately arranged in the circumferential direction;

three stator pole groups, in which a plurality of stator poles are arranged for each phase along or around the circumference so as to be positioned at substantially the same rotational phase position in terms of electrical angle; and

two loop windings axially arranged between the stator pole groups of individual phases; and

a voltage-variable unit VVU, in which three electrical power elements TR capable of on-off control of current are directly or indirectly connected in series to power source terminals VP and VN,

the motor is controlled by supplying three-phase voltages and currents to the three connecting terminals.