A rotary electrical machine includes a switch for supplying power to a field winding and controller. A ratio of an on-time to one switching cycle of the switch is defined as a duty ratio, and a duty ratio which is larger than the duty ratio corresponding to the field current that gives the maximum reduction amount of the inductance of the field winding with respect to an increasing amount of the field current in a range that the current can take and has a value less than 100% is set as a predetermined value. The controller calculates the duty ratio wherein an upper limit of the ratio is the predetermined value and turns on/off the switch based on the calculated duty ratio. Also, a relay and abnormality detection part that detects abnormality in the switch. The relay is switched to off in response to the occurrence of abnormality being detected.

A rotary electrical machine includes a stator, a field core, a rotor, and first and second air gaps. The stator includes an AC coil that generates a rotating magnetic field with an alternating current. The field core includes a field coil excited by a direct current. The rotor is disposed on an outer circumference of a starting apparatus and held rotatably about a rotational axis relative to the stator and the field coil. The first air gap is formed between the stator and the rotor, and allows a magnetic flux to flow therebetween. The second air gap is formed between the field core and the rotor, and allows a magnetic flux to flow therebetween. The second air gap defines an interval extending along a direction that intersects an axial direction of the rotational axis on one end surface of the rotor in the axial direction of the rotational axis.

A claw-pole motor comprising a non-magnetic rotary shaft having a longitudinal axis, a plurality of flux concentrators extending along the longitudinal axis of the rotary shaft, and a plurality of magnetic claw poles extending along the longitudinal axis of the rotary shaft, each of the plurality of flux concentrators alternating with each of the magnetic claw poles about the rotary shaft, and a stator having a plurality of coil assemblies, each coil assembly including a solenoid coil and an enclosure having a upper portion and lower portion, the upper portion and the lower portion of the enclosure having alternating stator teeth about the longitudinal axis.

A rotor for a rotating electric machine includes a field core having a plurality of claw-shaped magnetic pole portions, a field coil wound on the field core, and a hollow cylindrical core member disposed to cover radially outer peripheries of the claw-shaped magnetic pole portions of the field core. The core member is formed of a plurality of soft-magnetic bodies that are laminated in an axial direction of the core member. At least some of the soft-magnetic bodies forming the core member are fixed to one another by at least one staking portion that is formed along the axial direction of the core member.

In a rotor for a rotary electric machine, a claw pole assembly includes first claw poles and second claw poles. An annular cover member covers the outer circumferential surfaces of the first and second claw poles. The pole cover segments and the inter-pole cover segments are alternately arranged in the circumferential direction of the rotor. Each of the pole cover segments has a circular-arc shape around a first center, and each of the inter-pole cover segments has a circular-arc shape around a second center different from the first center. The first circumferential width of each pole cover segment and the second circumferential width of a corresponding one of the inter-pole segment adjacent to the pole cover segment have a predetermined ratio. The predetermined ratio varies in an axial direction of the rotor.

A brushless winding field type rotary electric machine equipped with a stator, a field core having a field coil, and a rotor. The field coil is in parallel with the rotor in the rotary member rotation shaft axial direction. The rotor has first and second magnetic poles respectively having first and second annular sections and first and second pawl sections, and an annular-shaped rotor core having first and second fitting sections into which the first and second pawl sections are respectively fitted, the first and second fitting sections being provided alternately along the circumferential direction, and the rotor core having through hollow sections each disposed between the first and second fitting sections. The first magnetic pole and the second magnetic pole are fixed to the rotor core without making contact with each other and the rotor core is constituted by stacking electromagnetic steel sheets in the axial direction.

A pole piece (106) for a rotor (100) of a rotary electric machine (20) includes a hub portion (104) and a plurality of pole segments (106) distributed evenly about the hub portion (104). The pole segments each have a base (116) that is connected to the hub portion (104) and a tip (118) that is disposed axially opposite the base (116) along an axis (60) of the pole piece (106). Each pole segment (106) defines circumferentially opposite side surfaces (120, 122) that extend between the base (116) and the tip (118). Each pole segment (106) also defines radially opposite outer and inner surfaces (124, 126) that extend between the side surfaces (120, 122). A groove is recessed in the side surfaces (120, 122) of each pole segment (106). A radially innermost portion (136) of the groove (130, 132) is arranged proximate to the radially outer surface.

In a rotating electric machine, a rotor includes a field core, a field coil and permanent magnets. The field core has a boss portion and claw-shaped magnetic pole portions. Each of the permanent magnets is arranged between one circumferentially-adjacent pair of the claw-shaped magnetic pole portions. A d-axis magnetic circuit and a magnet magnetic circuit share a magnetic path in at least parts thereof. Along the d-axis magnetic circuit, magnetic flux generated by the magnetomotive force of the field coil flows through the boss portion, one pair of the claw-shaped magnetic pole portions and a stator core. Along the magnet magnetic circuit, magnetic flux generated by the magnetic force of a corresponding one of the permanent magnets flows. The relationship of Ast>Af is satisfied, where Ast is a magnetic path cross-sectional area of a stator and Af is a magnetic path cross-sectional area of the rotor.

A rotary electric machine is equipped with a stator and a rotor. The rotor has a d-axis magnetic circuit that is produced by a magnetomotive force of a field winding, and magnet magnetic circuits that are produced by a magnetic force of permanent magnets. The d-axis magnetic circuit and a q-axis magnetic circuit have at least a part thereof that is common to both. The permeance of the d-axis magnetic circuit is smaller than the permeance of the q-axis magnetic circuit, when a load is being applied to the rotor. A control apparatus of the rotary electric machine has a switching circuit that controls the field current in the field winding, and a control section that makes the switching frequency of the switching circuit become higher when the field current is above a threshold value than when the field current is less than or equal to the threshold value.

A rotating electrical machine includes a rotor and a magnet unit. The rotating electrical machine also includes a cylindrical stator and a housing. The stator is equipped with a stator winding made up of a plurality of phase windings. The stator is arranged coaxially with the rotor and faces the rotor. The housing has the rotor and the stator disposed therein. The rotor includes a cylindrical magnet retainer to which the magnet unit is secured and an intermediate portion which connects between a rotating shaft of the rotor and the magnet retainer and extends in a radial direction of the rotating shaft. A first region located radially inside an inner peripheral surface of a magnetic circuit component made up of the stator and the rotor is greater in volume than a second region between the inner peripheral surface of the magnetic circuit component and the housing in the radial direction.