Hitachi, Ltd.

Hitachi Industrial Equipment Systems Co., Ltd.

Shinichi Wakui

Miyoshi Takahashi

Satoshi Kikuchi

Haruo Koharagi

Ryoichi Takahata

Keiji Noma

Hiroshi Hirayama

Kazumasa Ide

Masaharu Senoh

Shigeya Kawaminami

Masaharu Senoo

Takashi Seshimo

Haruo Miura

Yasuo Fukushima

Akitomi Semba

Naohiko Takahashi

Ryoichi Shiobara

Akeshi Takahashi

Yasuomi Yagi

Junji Sato

Tsukasa Taniguchi

Kado Miyakawa

Hidenari Otani

To provide a permanent magnet synchronous machine capable of expanding a high-speed operation range without reducing torque, and a pressing machine or an extrusion machine using the permanent magnet synchronous machine. In order to achieve the object described above, the present invention provides a permanent magnet synchronous electric machine having at least one permanent magnet on a radial surface of a rotor core, the permanent magnet having a rotor constituting a field pole, wherein a plurality of slits constituted by nonmagnetic material is provided on a core part between adjacent permanent magnets with opposite magnetic polarities of the rotor. According to the present invention, expansion of a high-speed operation range can be achieved without reducing torque.

Permanent magnet synchronous machine, and pressing or extrusion machine including permanent magnet synchronous machine

A permanent magnet type electric rotary machine includes a stator including a stator core having teeth and slots, and a rotor provided with permanent magnets as magnet poles in a rotor core. A pole core portion which between each of the permanent magnets and an outer surface of the rotor core is provided with a plurality of pole slits. A region of the pole core portion is defined by concave portions provided on q-axes to be interpolars on both sides of the pole core portion, and thereby configured that a gap between the outer surface on the q-axis of the rotor core and an inner surface of the stator core is larger than a gap between the outer surface on the d-axis of the pole core portion and the inner surface of the stator, so that magnetic fluxes from the permanent magnet pass through the pole core portion concentrately.

Permanent magnet type electric rotary machine and compressor using the same

In a permanent magnet type rotating electric machine comprising a stator of which concentratedly wound armature windings are disposed in a plurality of slots formed in a stator core so as to surround teeth and a rotor accommodating permanent magnets in a plurality of permanent magnet insertion holes formed in a rotor core, a part of outer circumferential faces of slots is formed to extend substantially in parallel with a part of inner circumferential faces of the teeth, thereby, a permanent magnet type rotating electric machine with limited noises can be realized.

Permanent magnet type rotating electric machine

A permanent magnetic type electric rotating machine includes: a stator having armature winding arranged in several slots formed in a stator core; and a rotor having permanent magnets held in several permanent magnetic insertion holes formed in a rotor core, in which a peripheral surface of the rotor core is configured to be a combination of arcs around two points different from a center of the rotor core for each magnetic pole in such a manner that when an axis extending in a central direction of a magnetic pole of the rotor is a d axis, and an axis extending in a direction between magnetic poles that is offset from the central direction of the magnetic pole by 90 electrical degrees is a q axis, a radial distance from a center of the rotor core to a periphery of the rotor is reduced gradually from the d axis to the q axis.

Permanent magnet type electric rotating machine

In an ultra-permanent-magnet-type electric rotating machine including a stator in which a winding of armatures is wound in each of a plurality of slots of a stator core, and a rotor having permanent magnets respectively inserted into permanent-magnet-inserting holes in a magnetic steel sheet ring provided at an outer periphery of a conductive and magnetic shaft, the thickness of the stator core is 0.1 to 0.2 mm, and the magnetic steel sheet ring is made of a high-tensile-strength magnetic steel sheet had tensile strength of 80 kg/mm or more.

Permanent-magnet-type electric rotating machine and air compressor and generator using the same

In order to make any voltage imbalance between the winding circuits of each phase small and to simplify the edge structure of the armature winding, in a rotating electric machine of four poles, having slots of 9n (1&lE;n&lE;7) pieces provided for the stator core with a double-layer winding per each slot, and an armature winding of three-phase star connection being constituted with three winding circuits connected in parallel in each phase, two of the four poles of each phase are constituted with only one of the three winding circuits.

Armature winding and rotating electric machine using the same

The rotor 2 of a rotating field type turbine generator is provided with slots 3 for accommodating the field windings, wedges 4 positioned at the portions of the magnetic poles on the rotor 2 for holding the field windings and wedges 5 positioned between the magnetic poles on the rotor. These wedges 4 and 5 are constituted by metal bars without joints to enhance damper effect thereby. Magnetomotive forces due to higher harmonics, which causes temperature rise of the rotor 2 and torque ripple during starting with thyristors, induces an elliptic rotating magnetic field having the longer diameter on d axis extending in the direction of magnetomotive force induced by the field windings and the shorter diameter on q axis perpendicular to d axis, and thus a larger eddy current is induced flowing along q axis on the rotor 2 than that flowing along d axis. Therefore the thickness d' in radial direction of the wedges 5 positioned between the magnetic poles on the rotor 2 is determined larger than the thickness d in radial direction of the wedges 4 positioned at the portions of the magnetic poles on the rotor 2 to reduce the resistance of the wedges 5 and to easily lead the eddy current flowing in the axial direction of the rotor 2, thereby a good thermal balance over the entire portions on the rotor 2 is achieved. Drawings to Be Selected FIG. 1

Turbine generator

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Hitachi, Japan

Shinichi Wakui