US 2018/0019628 A1Published application

Reluctance motor and manufacturing method for rotor core used in reluctance motor

AssigneeMitsubishi Electric Corporation

InventorsKazumasa ITO, Shinichi YAMAGUCHI, Haruyuki KOMETANI, Masatsugu NAKANO, Norihiro ACHIWA, Yoshiki MAEDA, Masaya HARAKAWA

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Abstract

With regard to an end portion shape of a slit formed in a rotor core in which flux barriers are formed in a circumferential direction in an identical number to the number of poles by arranging one or more slits and core layers alternately in a radial direction, an end portion of a slit is shaped such that, when mg is set as the number of slit end portions, ni is set as a natural number no smaller than 1, α and β are set as numbers within a range of −¼ to ¼, q is set as a natural number no smaller than 1, and Ns is set as the number of slots, intervals δgi and εgi from a first slit end to an ith slit end of a slit wall on an identical circumferential direction side satisfy specific mathematical formulae.

Claims9

Dependent claims

A reluctance motor comprising:

a rotor configured by fixing a rotor core to a shaft;
and
a stator having slots in which windings are housed,
the rotor and the stator being disposed to be free to rotate via a magnetic gap,
wherein the number of the slots is set as Ns,
the rotor core includes flux barriers formed in a circumferential direction in an identical number to the number of poles by arranging one or more slits and core layers alternately in a radial direction,
slit end portions close to a rotor outer periphery, of the slits provided for each pole, are divided into at least one group,
the number of slit end portions included in one group having a group number g is set as mg, and numbers from first to mgth are allocated to the slit end portions sequentially from a right side of the circumferential direction, and
the flux barriers are respectively configured such that, with respect to slit walls extending from the rotor outer periphery toward an inner periphery in each slit end portion, when an interval from a first slit end to an ith slit end of a right side slit wall, as seen in the circumferential direction, is set as δgi, n1 is set as a natural number no smaller than 1, α is set as a number within a range no smaller than −¼ and no larger than ¼, and q is set as a natural number no smaller than 1, δgi satisfies Equation (1) shown below
δ
i
g
=
2


π
qN
s

(
i
-
1
m
g
+
n
i
+
α
)

[
rad
]
(
1
)
and when an interval from a first slit end to an ith slit end of a left side slit wall, as seen in the circumferential direction, is set as εgi, l1 is set as a natural number no smaller than 1, β is set as a number within a range no smaller than −¼ and no larger than ¼, and q is set as a natural number no smaller than 1, εgi satisfies Equation (2) shown below
ɛ
i
g
=
2


π
qN
s

(
i
-
1
m
g
+
l
i
+
β
)

[
rad
]
.
(
2
)

68 more elements

A manufacturing method for a rotor core used in a reluctance motor, the reluctance motor having a rotor configured by fixing a rotor core to a shaft, and a stator having slots in which windings are housed, the rotor and the stator being disposed to be free to rotate via a magnetic gap,

wherein, in a case where the number of the slots is set as Ns,
the rotor core includes flux barriers formed in a circumferential direction in an identical number to the number of poles by arranging one or more slits and core layers alternately in a radial direction,
slit end portions close to a rotor outer periphery, of the slits provided for each pole, are divided into at least one group,
the number of slit end portions included in one group having a group number g is set as mg, and
numbers from first to mgth are allocated to the slit end portions sequentially from a right side of the circumferential direction,
the manufacturing method comprises a step of forming the slits by implementing punching processing on a thin steel plate such that, with respect to slit walls extending from the rotor outer periphery toward an inner periphery in each slit end portion, when an interval from a first slit end to an ith slit end of a right side slit wall, as seen in the circumferential direction, is set as δgi, n1 is set as a natural number no smaller than 1, α is set as a number within a range no smaller than −¼ and no larger than ¼, and q is set as a natural number no smaller than 1, δgi satisfies Equation (5) shown below
δ
i
g
=
2


π
qN
s

(
i
-
1
m
g
+
n
i
+
α
)

[
rad
]
(
5
)
and when an interval from a first slit end to an ith slit end of a left side slit wall, as seen in the circumferential direction, is set as εgi, l1 is set as a natural number no smaller than 1, β is set as a number within a range no smaller than −¼ and no larger than ¼, and q is set as a natural number no smaller than 1, εgi satisfies Equation (6) shown below
ɛ
i
g
=
2


π
qN
s

(
i
-
1
m
g
+
l
i
+
β
)

[
rad
]
.
(
6
)

65 more elements

Dependencies are inferred from the claim text.

Facts

Application: 15/548,444Filed 28 Jan 2016
Priority: JP 2015-0411223 Mar 2015
Published: 18 Jan 2018
Term ends: Not estimatedThe source records don’t support an estimate.

Classification7 codes

H02K 1/246
Rotor cores with salient poles ; Variable reluctance rotors: variable reluctance rotors
H02K 1/22
Characterised by the shape, form or construction: rotating parts of the magnetic circuit
H02K 1/24
Rotating parts of the magnetic circuit: rotor cores with salient poles ; Variable reluctance rotors
H02K 1/276
The rotor consisting of magnets or groups of magnets arranged with alternating polarity: magnets embedded in the magnetic core, e.g. interior…