US 2013/0093284 A1Published application

Rotor of electric rotating machine

AssigneeDenso Corporation

InventorRyosuke Utaka

Life of this patent

Estimating the term…

Loading patent…

Abstract

The waveform of a magnetomotive force generated by a rotor is comprised of a plurality of sections that respectively correspond to a plurality of magnetic poles of the rotor. When viewed along the axial direction of a rotor core, each of the sections of the waveform includes two oblique lines and a connection line. Each of the oblique lines extends from a 0 reference line, which is defined by an outer peripheral surface of the rotor core, obliquely with respect to a radial direction of the rotor core. The connection line connects the two oblique lines in the circumferential direction of the rotor core. Moreover, representing the circumferential width of the connection line by 2π·Duty, the circumferential width of the oblique lines by 2π·Slope, the radial height of the oblique lines by B, the order of a harmonic component of the magnetomotive force by n, and the amplitude of the nth harmonic component by Amp1, then the following relationship is satisfied: Slope=k/n (here, k is an arbitrary natural number). The amplitude of the nth harmonic component is determined by: Amp1 (n)=(4B/nπ)×{sin (nπ·Slope)/nπ·Slope}×sin {nπ(Duty+Slope)} . . . Equation (1).

Claims9

Dependent claims

A rotor of an electric rotating machine, the rotor comprising an annular rotor core and a plurality of permanent magnets embedded in the rotor core,

wherein
a plurality of magnetic poles are formed in the vicinity of an outer periphery of the rotor core by the permanent magnets,
the magnetic poles are arranged in a circumferential direction of the rotor core at predetermined intervals so that polarities thereof alternate between N and S in the circumferential direction,
a waveform of a magnetomotive force generated by the rotor is comprised of a plurality of sections that respectively correspond to the magnetic poles,
when viewed along an axial direction of the rotor core, the sections of the waveform either protrude radially outward from a 0 reference line, which is defined by an outer peripheral surface of the rotor core, or are recessed radially inward from the 0 reference line,
among the sections of the waveform, those sections which protrude radially outward are alternately arranged in the circumferential direction of the rotor core with those sections which are recessed radially inward,
each of the sections of the waveform includes two oblique lines, each of which extends from the 0 reference line obliquely with respect to a radial direction of the rotor core, and a connection line that connects the two oblique lines in the circumferential direction of the rotor core, and
representing a circumferential width of the connection line by 2π·Duty, a circumferential width of the oblique lines by 2π·Slope, a radial height of the oblique lines by B, the order of a harmonic component of the magnetomotive force by n, and an amplitude of the nth harmonic component by Amp1, then the following relationship is satisfied:
Slope=k/n (here, k is an arbitrary natural number),
the amplitude of the nth harmonic component being determined by the following Equation (1):
Amp
1

(
n
)
=
4


B
n


π
·
sin

(
n


π
·
Slope
)
n


π
·
Slope
·
sin

{
n


π

(
Duty
+
Slope
)
}
.
(
1
)

58 more elements

A rotor of an electric rotating machine, the rotor comprising an annular rotor core and a plurality of permanent magnets embedded in the rotor core,

wherein
a plurality of magnetic poles are formed in the vicinity of an outer periphery of the rotor core by the permanent magnets,
the magnetic poles are arranged in a circumferential direction of the rotor core at predetermined intervals so that polarities thereof alternate between N and S in the circumferential direction,
a waveform of a magnetomotive force generated by the rotor is comprised of a plurality of sections that respectively correspond to the magnetic poles,
when viewed along an axial direction of the rotor core, the sections of the waveform either protrude radially outward from a 0 reference line, which is defined by an outer peripheral surface of the rotor core, or are recessed radially inward from the 0 reference line,
among the sections of the waveform, those sections which protrude radially outward are alternately arranged in the circumferential direction of the rotor core with those sections which are recessed radially inward,
each of the sections of the waveform includes two oblique lines, each of which extends from the 0 reference line obliquely with respect to a radial direction of the rotor core, and a connection line that connects the two oblique lines in the circumferential direction of the rotor core, and
representing a circumferential width of the connection line by 2π·Duty, a circumferential width of the oblique lines by 2π·Slope, a radial height of the oblique lines by B, the order of a harmonic component of the magnetomotive force by n, and an amplitude of the nth harmonic component by Amp1, then the following relationship is satisfied:
Duty+Slope=k/n (here, k is an arbitrary natural number),
the amplitude of the nth harmonic component being determined by the following Equation (1):
Amp
1

(
n
)
=
4


B
n


π
·
sin

(
n


π
·
Slope
)
n


π
·
Slope
·
sin

{
n


π

(
Duty
+
Slope
)
}
.
(
1
)

58 more elements

A rotor of an electric rotating machine, the rotor comprising an annular rotor core and a plurality of permanent magnets embedded in the rotor core,

wherein
a plurality of magnetic poles are formed in the vicinity of an outer periphery of the rotor core by the permanent magnets,
the magnetic poles are arranged in a circumferential direction of the rotor core at predetermined intervals so that polarities thereof alternate between N and S in the circumferential direction,
in an outer peripheral surface of the rotor core, there is provided, at a circumferential center of each of the magnetic poles, either a groove that is recessed radially inward and extends in an axial direction of rotation or a protrusion that protrudes radially outward and extends in the axial direction of rotation,
a waveform of a magnetomotive force generated by the rotor is comprised of a plurality of sections that respectively correspond to the magnetic poles,
when viewed along an axial direction of the rotor core, the sections of the waveform either protrude radially outward from a 0 reference line, which is defined by the outer peripheral surface of the rotor core, or are recessed radially inward from the 0 reference line,
among the sections of the waveform, those sections which protrude radially outward are alternately arranged in the circumferential direction of the rotor core with those sections which are recessed radially inward,
each of the sections of the waveform includes two first oblique lines, each of which extends from the 0 reference line obliquely with respect to a radial direction of the rotor core, and a first connection line that connects the first oblique lines in the circumferential direction of the rotor core,
the first connection line includes two second oblique lines, each of which extends obliquely with respect to a radial direction of the rotor core, and a second connection line that connects the second oblique lines in the circumferential direction of the rotor core, and
representing a circumferential width of the first connection line by 2π·Duty1, a circumferential width of the first oblique lines by 2π·Slope1, a radial height of the first oblique lines by B1, a circumferential width of the second connection line by 2π·Duty2, a circumferential width of the second oblique lines by 2π·Slope2, a radial height of the second oblique lines by B2, the order of a harmonic component of the magnetomotive force by n, and an amplitude of the nth harmonic component by Amp2, which is determined by the following Equation (2), then B2 satisfies the flowing Equation (3):
Amp
2

(
n
)
=
4


B
1
n


π
·
sin

(
n


π
·
Slope
1
)
n


π
·
Slope
1
·
sin

{
n


π

(
Duty
1
+
Slope
1
)
}
+
4


B
2
n


π
·
sin

(
n


π
·
Slope
2
)
n


π
·
Slope
2
·
sin

{
n


π

(
Duty
2
+
Slope
2
)
}
,
(
2
)
B
2
=
-
Slope
2
Slope
1
·
sin

(
n


π
·
Slope
1
)
sin

(
n


π
·
Slope
2
)
·
sin

{
n


π

(
Duty
1
+
Slope
1
)
}
sin

{
n


π

(
Duty
2
+
Slope
2
)
}
·
B
1
.
(
3
)

180 more elements

Dependencies are inferred from the claim text.