Hitachi, Ltd.

Hitachi Industrial Equipment Systems Co., Ltd.

Keiji Noma

Satoshi Kikuchi

Haruo Koharagi

Miyoshi Takahashi

Masaharu Senoh

Ryoichi Takahata

Shinichi Wakui

Kazuo Sato

Kouki Yamamoto

Kohei Ishii

Hiroshi Hirayama

Masaharu Senoo

Shigeya Kawaminami

Takashi Seshimo

Tadashi Fukushima

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

An air conditioner comprising a compressor including a compression unit and a permanent magnet rotating electric machine, wherein the permanent magnet rotating electric machine includes a stator, into which concentratively wound armature windings are inserted in such a way as to surround a plurality of teeth formed in a stator core, and a rotor having permanent magnets accommodated into a plurality of permanent magnet inserting holes formed in a rotor core. Each pair of adjacent ones of said permanent magnets is arranged generally in one of a convex V-shaped configuration and a convex U-shaped configuration with respect to a rotor axis, and a substantially V-shaped recess portion is formed between adjacent poles in outer circumferential surface portions of the rotor core.

Air conditioner having permanent magnet rotating electric machine

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 magnet rotating electric machine that comprises a stator, into which concentratively wound armature windings are inserted in such a way as to surround a plurality of teeth formed in a stator core, and a rotor having permanent magnets accommodated into a plurality of permanent magnet inserting holes formed in a rotor core. In this rotating electric machine, the permanent magnets are convex V-shaped or U-shaped with respect to a rotor axis. Moreover, nearly V-shaped recess portions, each of which is placed between adjacent poles, are formed in outer circumferential surface portions of the rotor core. Thus, torque caused by magnetic flux due to the magnets is increased, while armature reaction magnetic flux generated by an armature current is reduced. Consequently, q-axis inductance is reduced, so that armature current commutation is quickly achieved. Thus, the permanent magnet rotating electric machine using the stator employing concentrated windings and also using the magnet-embedded rotor is stably driven even when driven by a position sensorless inverter in the case of 120 degree energization.

Permanent magnet rotating electric machine

The present invention provides a permanent magnet rotating electric machine that comprises a stator, into which concentrated wound armature windings are inserted in such a way as to surround a plurality of teeth formed in a stator core, and a rotor having rare earth permanent magnets inserted into a plurality of permanent magnet holes, which are formed in a rotor core and used for accommodating permanent magnets. In this permanent magnet rotating electric machine, the permanent magnets are each shaped like a convex &ldquo;V&rdquo; or &ldquo;U&rdquo; with respect to the shaft of the rotor. Moreover, a ratio of the width W of an interpole core between the permanent magnets to the width Xg of the gap between the stator core and the rotor core is set in such a manner as to satisfy the following condition: 0.8&lE;W /Xg&lE;13.2. Thus, even when this rotating electric machine is driven by a position sensorless inverter in the case of 120 degree energization, the system efficiency is enhanced.

Growing community of inventors

Shisui, Japan

Keiji Noma