Hitachi, Ltd.

Hitachi Appliances, Inc

Adv Antest Corporation

Hitachi Industrial Equipment Systems Co., Ltd.

Hiroyuki Mikami

Mamoru Kimura

Satoshi Kikuchi

Daisuke Kori

Kenichi Hattori

Kazumasa Ide

Motonobu Iizuka

Tetsuo Fujigaki

Akihito Nakahara

Tsukasa Taniguchi

Seikichi Masuda

Hideyuki Harada

Haruo Koharagi

Tadahiro Shimozono

Tomio Yoshikawa

Masayasu Fujieda

Hideyuki Kumakura

Keiji Tanaka

Atsushi Abe

Kazuhiko Takahashi

Fumio Jyoraku

Kazuo Nishihama

Miyoshi Takahashi

Yasushi Iwai

Baiying Huang

Keiichiro Kaihatsu

Shuji Aizawa

Kenji Tojo

Masanori Sawahata

Masashi Miyake

Masaru Ohtahara

Yasutaka Tsuruki

Akeshi Takahashi

Shuji Mizutani

An object of the present invention is to provide a squirrel-cage induction motor with high efficiency. In a squirrel-cage induction motor including a stator in which stator windings are wound in a number of stator slots arranged at intervals in the vicinity of the inner periphery of a stator core and a rotor in which rotor conductors are embedded in a number of rotor slots arranged at intervals in the vicinity of the outer periphery of a rotor core and end rings are provided at both ends of the rotor core, the rotor core is formed of a plurality of blocks, an annular short-circuit ring is provided between respective blocks of the rotor core to short-circuit the rotor conductors, and laminated thickness of the rotor core is made larger than laminated thickness of the stator core.

Squirrel-cage induction motor

A squirrel cage induction motor includes: a stator core (); a plurality of stator slots () radially disposed in a circumferential direction of the stator core () with predetermined intervals; a plurality of stator windings () housed in the stator slots respectively; a rotor core (); a plurality of rotor slots () radially disposed in a circumferential direction of the rotor core () with predetermined intervals; a plurality of rotor conductors () housed in the rotor slots () respectively. The stator windings () and the rotor conductors () includes electrically conductive materials mainly composed of copper. An area ratio of a total area of the stator slots () to a total area of the rotor slots () is not smaller than 2.7 and not greater than 8.0 to provide compatibility between the starting characteristic (starting torque) and the steady characteristic (for a high efficiency) can be provided.

Squirrel cage induction motor and squirrel cage induction motor driving system

A rotating electrical machine includes: a rotor comprising a rotor core and a field winding wound round the rotor core; and a stator comprising a stator core and a stator winding wound round the stator core. The stator is arranged in opposition to the rotor with a predetermined spacing therebetween. the stator core is formed by punching a split piece, which comprises teeth for insertion of the stator winding thereinto and a core back on an outer periphery thereof, from a magnetic steel sheet, and laminating a plurality of those circular configurations in an axial direction, in which a plurality of the split pieces are arranged in a circle in a circumferential direction. The stator core has magnetic steel sheets, which are different in magnetic permeability in a diametrical direction, laminated at an axial end region of and in an axial central region of the stator core.

Rotating electrical machine

A synchronous generatorincluding a rotor having a field winding placed in the slots thereof and a stator having an armature winding placed in the slots thereof, wherein the value of the number of slots per two poles in stator minus the number of slots per two poles in rotor is equal to or greater than +9, or equal to or smaller than &#x2212;9.

Synchronous generator and synchronous generator system for reducing distortion of current waveform

There is provided a self-starting permanent magnet synchronous motor in which a center axis of magnetic poles of a rotor is assumed to be a d axis, an axis deviated from the magnetic pole center axis by an electric angle of 90 degrees is assumed to be a q axis, at least two or more starting bars which are arranged near the d axis are arranged on a bore side of the bars near the q axis and are arranged in parallel with the q axis, so that a stable starting torque can be generated irrespective of a generating position of a stator magnetic flux which changes due to applying timing of a power source and a phase of a voltage, and a vibration/noises at the time of a stationary operation can be reduced.

Self-starting permanent magnet synchronous motor and compressor and refrigeration cycle using the same

A permanent magnet type rotary electric machine has a rotor having a rotor core and permanent magnets buried into the rotor core by being incorporated into respective permanent magnet slots. The permanent magnet slot per one pole is divided at least into four slots along an outer circumferential direction in the rotor core, and in respective rest core-portions between adjacent divided permanent magnet slots in the rotor core, a width of a first rest core-portion at the middle of each pole and a width of a second rest core-portion between adjacent poles of different polarities are formed larger than that of the others.

Permanent magnet type rotary electric machine

Rotating electrical machine with different lamination steel kinds and spacing

Movement of magnets due to centrifugal force is restricted. In a permanent magnet rotating electrical machinehaving a statorand a rotor coreprovided with a plurality of permanent magnetsinserted in an outer circumferential portion of the rotor, each permanent magnethas inclined surfaces on the outer circumferential side of the rotorand the thinnest portions of the inclined surfaces are adjacent to permanent magnets of the opposite polarity. Further, each magnethas a convex-shaped cross section and is divided into two magnet segments. A magnetic pole bridgeis formed at the boundary of the permanent magnet segments. Thus, movement of the permanent magnet segmentsdue to centrifugal force is firmly restricted, and the peeling off of the rotor coreand the permanent magnet segmentsfrom each other is prevented.

Permanent magnet rotating electrical machine and permanent magnet rotating electrical machine system

A permanent magnet electrical rotating machine having a permanent magnet rotor and a stator, wherein:

Permanent magnet electrical rotating machine, wind power generating system, and a method of magnetizing a permanent magnet

A rotor is deployed such that the rotor becomes coaxially rotatable with a stator. A shaft is fixed onto the axis of a rotor iron-core. 1-pole constituting magnet slots are deployed into V-character pattern along an outer circumference portion of the rotor iron-core. Permanent magnets are embedded into the magnet slots. For the 1 pole, the 2 pieces of same-polarity permanent magnets are embedded into the V-character pattern. The configuration of each embedded permanent magnet is designed as follows: From the thickness of the permanent-magnet edge portion on the inner-diameter side of the rotor iron-core, which becomes the center of the V-character pattern, the thickness of the permanent magnet gradually increases toward the outer-diameter side of the rotor iron-core, which become the right and left edge portions of the V-character pattern. Simultaneously, curved lines are provided on both edge portions of the permanent magnet.

Permanent-magnet type electric rotating machine and permanent-magnet type electric rotating machine system for automobile or train

A self-starting type permanent magnet synchronous motor comprises a stator and a rotor. The rotor comprises a rotor core having a plurality of slots provided in an outer periphery thereof and a cage winding comprising conductive bars embedded in the slots and conductive end rings that short-circuit the conductive bars on both end faces of the bars in an axial direction thereof. The rotor core comprises at least one magnet insertion hole arranged on an inner peripheral side from the slots, and at least one permanent magnet embedded in the at least one magnet insertion hole. When a pole center axis is denoted as a d-axis and an axis deviating from the pole center axis by an electrical angle 90&#xb0; is denoted as a q-axis, a flux content generated by the cage winding during start-up becomes maximal in the vicinity of and on one of the d-axis and the q-axis.

Self-starting type permanent magnet synchronous motor and a compressor using the same

A permanent magnet rotating electric machine has a stator provided with a plurality of windings, and a rotor in which magnets are disposed in slots formed in a rotor core along an outer circumference thereof. The rotor core is fixed on a rotary shaft rotating inside the stator, and one magnetic pole is constituted by each group of three or more of the magnets. A total angle occupied by the group of magnets constituting one magnetic pole is in the range of 150 to 165 degrees in terms of an electrical angle.

Rotor of permanent magnet rotating electric machine

A permanent magnet electrical rotating machine having a permanent magnet rotor and a stator, wherein: a plurality of permanent magnets are disposed in a rotor iron core of the permanent magnet rotor along a periphery of the rotor iron core, polarities thereof being alternately changed; a cooling airflow channel is formed between each pair of adjacent opposite poles on the rotor iron core; and the cooling airflow channel has an approximately trapezoidal shape on an outer periphery side of the rotor iron core; and extends from an end on a central side in a radial direction of the approximately trapezoidal shape to a radial center.

Growing community of inventors

Hitachinaka, Japan

Hiroyuki Mikami