Hitachi, Ltd.

Hitachi Haramachi Electronics Co., Ltd.

Other

Yutaka Higashimura

Akira Tanaka

Ryuichi Saito

Kazuji Yamada

Keiji Suzuki

Kazuhiro Suzuki

Nobuya Koike

Masahiro Koizumi

Jin Onuki

Yoshihiko Koike

Isao Kobayashi

Yasutoshi Kurihara

Mamoru Sawahata

Tadao Kushima

Takashi Haramaki

Shigeki Sekine

Takashi Hosokawa

Hideo Shimizu

Hideya Kokubun

Koji Obata

Mitsuru Onoda

Hiroshi Miyao

Keiji Fukushi

Takanori Satoo

Hiroyuki Kamiya

Makoto Takamura

Shinei Huzioka

Kenzo Kadotani

Syuzou Iwaasa

Yoshimi Kurahara

With a rotating electric machine testing method for applying a test voltage to an armature winding of the rotating electric machine to thereby test insulation performance of the armature winding, in the case where a rated voltage of the armature winding of the rotating electric machine is E, and an insulation test voltage of an armature winding of a sine wave voltage drive rotating electric machine at the rated voltage E is E/&#x221a;{square root over (3)} or E, a test voltage Vapplied to an armature winding of the inverter drive rotating electric machine is set to V=&#x3b1;&#xb7;E/&#x221a;{square root over (3)} or V'=&#x3b1;&#xb7;E, respectively, provided that &#x3b1;(=t/t), if the insulation thicknesses of the sine wave drive rotating electric machine is tand of the inverter drive rotating electric machine is t, thereby conducting a test on any of the AC voltage-current characteristic, AC tan &#x3b4;, and AC partial-discharge characteristics.

Method for testing an inverter drive rotating electric machine

In a rotating electrical machine, a conductive foil or conductive rubber is applied to the surface of insulation layer of a conductor series connection area or to the surface of insulation layer of a turn conductor of coils of rotating electrical machine winding, waveforms of grounding voltages of the individual turn conductor portions are measured through the medium of an electrostatic capacitance of the insulation layer of coil conductor series connection area or through the medium of the insulation layer of coil turn conductor, and a partial discharge is measured while measuring a voltage developing in the coil or across a winding turn in the coil from a difference between the waveforms of grounding voltages.

Method of testing partial discharge of rotating electrical machine driven by inverter

When a rotating electrical machine winding is inserted into a slot with a protective insulation intervening between them, a semiconductive insulating layer is lap-wound between an interlayer insulating layer of the rotating electrical machine winding and the protective insulation, the semiconductive insulating layer being formed by center-folding a continuous semiconductive sheet in the longitudinal direction. A thermal stress relaxation layer is provided inside the center-folded continuous semiconductive sheet so that thermal stress exerted in thickness direction of the insulating layers is absorbed.

Rotating electrical machine winding, rotating electrical machine, and semiconductive insulating component used therein

A semiconductor device in which electrodes of a plurality of semiconductor elements are bonded onto at least one of a plurality of electrode patterns on an insulator substrate, the other surface of the insulator substrate being bonded to a heat dissipating base. The upper surface of the heat dissipating base is covered with a member for cutting off the semiconductor elements from the outer environment. Terminals electrically connect the electrodes on said insulator substrate and the electrode placed outside the cutoff member. The material of the heat dissipating base has a linear expanding coefficient larger than that of the semiconductor element and smaller than three times that of the semiconductor element, and a thermal conductivity larger than 100 W/mK. The semiconductor elements are arranged on at least one electrode surface and in at least two regions divided by the other electrode surface on the insulator substrate.

Circuit board

A semiconductor device in which a plurality of semiconductor elements are bonded onto at least one electrode pattern on an insulator substrate formed a plurality of electrode patterns on the main surface, each of the electrodes of the semiconductor element being electrically connected to the electrode pattern, the other surface of the insulator substrate being bonded to a heat dissipating base, the upper surface of the heat dissipating base being covered with a member for cutting off the semiconductor elements from the outer environment, terminals electrically connecting the electrodes on said insulator substrate and the electrode placed outside the cutoff member being provided, wherein the material of the heat dissipating base has a linear expanding coefficient larger than the linear expansion coefficient of the semiconductor element and smaller than three times of the linear expansion coefficient of the semiconductor element, and a thermal conductivity larger than 100 W/mK, the semiconductor elements being arranged on at least one electrode surface and in at least two regions divided by the other electrode surface on the insulator substrate.

Semiconductor device

Semiconductor device having power semiconductor elements

An electrically insulated coil, characterized in that an electrical insulation layer wound around an electrical conductor is formed by laminating layers of glass flakes having a thickness of 0.2-1 .mu.m and a diameter of 40-250 .mu.m on a backing member of a sheet-like electrical insulation material and by impregnating with a semi-cured thermosetting resin. An electrically insulated coil is provided, having an excellent partial discharge resistance as well as having a high dielectric break down strength even when subjected to a large mechanical distortion.

Sheet material for electrical insulation, prepreg and electrically

A stator of a submerged motor is provided with cylinders formed of carbon fiber reinforced plastics of superhigh precision. To obtain flawless joints between the cylinders of carbon fiber reinforced plastics and the end covers increased wall thickness portions are provided at opposite axial end portions of an inner cylinder near joints of the inner cylinder with the end covers, one increased wall thickness portion being located at one axial end portion on an outer side surface thereof and the other increased wall thickness portion being located at the other axial end portion on an inner side surface thereof. Thus, the inner cylinder has a small wall thickness at an axial central portion to reduce an eddy current loss while its wall thickness is increased at the opposite axial end portions to improve mechanical strength and facilitate joining of the end covers to the inner cylinder.

Stator of submerged motor

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Hitachi, Japan

Yutaka Higashimura