Hitachi, Ltd.

Yasuomi Yagi

Kenichi Hattori

Takashi Watanabe

Hideaki Mori

Tadashi Sonobe

Atsushi Ishihara

Akitomi Semba

Junji Sato

Shinsaku Hakuta

Eiji Tsuji

Kazumasa Ide

Akiyoshi Komura

Ryoichi Shiobara

Shigeo Amagi

Takeo Nemoto

Kengo Iwashige

Mitsuru Onoda

Keiji Kobashi

Saburo Usami

Tomoya Tsunoda

Kado Miyakawa

Ken Takahashi

Haruo Koharagi

Miyoshi Takahashi

Hisanao Ogata

Shinichi Wakui

Takanobu Mori

Fumio Shibata

Yoshinori Hakuraku

An electric rotating machine capable of lowering the temperature of a rotor disposed, wherein at least one of closed ventilation loops for cooling is formed, one of the loops constituting a ventilation passage communicating with an exhaust side through a heat source of the end of the generator to a cooler, thereby to supply cooling wind to the rotor after it passes through the cooler.

Electric rotating machine

Dynamo-electric machine

A rotating machine having a stator core and coolers for cooling a cooling medium which is circulated inside the machine by the rotation of a fan installed near a rotating axis of the rotating machine. The coolers being installed in a ventilation passage for the cooling medium and including at least one cooler installed in one ventilation passage extending from an exhaust side of the fan to a suction side of the fan via the stator core, and at least another cooler installed in another ventilation passage extending from the exhaust side of the fan in the one ventilation passage to an inside of an inner surface of the stator core.

Rotating machine with plural coolers in plural ventilation passages

An electric rotating machine having a rotor, rotatably disposed in an inner radius side of a stator through a gap, including rotor windings contained in a plurality of slots formed in a rotor core, a slot insulation placed between the rotor winding and the slot, an insulation block placed between a wedge arranged at a peripheral side of the rotor core outward of the rotor winding of the slot and the rotor winding. At least one of the slot insulation and the insulation block is an insulation formed by filling or mixing granular and/or short-fiber insulating materials having a thermal conductivity higher than 5 W/m&middot;K in a resin and a thermal conductivity in a thickness direction higher than 0.35 W/m&middot;K.

A rotating machine having a stator core and being equipped with coolers for cooling a cooling medium which is circulated inside the machine by the rotation of a fan installed near a rotating axis of the rotating machine. The coolers are installed in a ventilation passage for the cooling medium and include a primary cooler installed in a primary ventilation passage extending from an exhaust side of the fan to a suction side of the fan via the stator core, and a secondary cooler installed in a secondary ventilation passage extending from the exhaust side of the fan in the primary ventilation passage to an inside of an inner surface of the stator core via the stator core.

Rotating machine

A rotating machine having a core and being equipped with coolers for cooling a cooling medium which is circulated inside the machine by the rotation of a fan installed near the rotating axis. The coolers are installed in a ventilation passage for the cooling medium and comprise a primary cooler installed in a primary ventilation passage extending from the exhaust side of a fan installed near the rotating axis to the suction side of said fan via the core, and a secondary cooler installed in a secondary passage that is branched from the primary ventilation passage.

A rotating machine having a stator core and being equipped with coolers for cooling a cooling medium which is circulated inside the machine by the rotation of a fan installed near the rotating axis. The coolers are installed in a ventilation passage for the cooling medium and comprise a primary cooler installed in a primary ventilation passage extending from the exhaust side of a fan installed near the rotating axis to the suction side of the fan via the stator core, and a secondary cooler installed in a secondary ventilation passage extending from the exhaust side of the fan in the primary ventilation passage to the inside of the inner surface of the stator core via the stator core.

An the electric rotating machine which is compact and of reduced cost by improving the thermal conductivity of the main insulation in the thickness direction while maintaining the insulation breakdown voltage of the main insulation high. The initial breakdown voltage V in the thickness direction of the main insulator 30 of the stator winding 3 is higher than 20 kV/mm, and the thermal conductivity &lgr; in the thickness direction is within a range of 0.35 to 1 W/m&middot;K, and the product V&lgr; of the initial breakdown voltage V and the thermal conductivity &lgr; satisfies a relationship of 7&lE;V&lgr;&lE;20 (MWA/m,&middot;K). The amount of resin is within a range of 20 to 50 weight % of the main insulation material.

Electric rotating machine with reduced thickness and volume of insulation

In order to provide a rotating machine in which the temperature increase distribution inside the machine can be equalized, not only is a primary cooler installed in the primary ventilation passage that extends from the exhaust side of the fans and installed on the rotating axis to the suction side of the fans and via the core, but a secondary cooler is installed in the secondary ventilation passage that is branched from the primary ventilation passage, thus making it possible to further cool part of the cooling medium, which has once been cooled by the primary cooler, by means of the secondary cooler, that is, to cool the cooling medium by circulating it through the coolers twice.

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

The rotor for a dynamo electric machine serving as a synchronous generator as well as being designed operable as a variable speed motor for starting a prime mover for the synchronous generator, the rotor (1) comprising a rotor core (2), a plurality of slots (4) disposed around the circumference of the rotor core (2) and extending along the axial direction of the rotor core (2), rotor windings (3) being accommodated in the slots (4) and wedges (6) being accommodated in the slots (4) over the rotor windings (3) near at the surface of the rotor core (2) for preventing the rotor windings (3) from being pushed out due to a centrifugal force caused by rotation of the rotor (1), wherein wedges (6) where an eddy current flows are formed by Cu-0.05.about.4 wt % Zr-0.3.about.5 wt % Ni-0.2.about.1.5 wt % Si having a 0.2% proof stress equal to or more than about 20 Kg/mm.sup.2 and an electrical conductivity equal to or more than about 20% IACS (International Annealed Copper Standard), whereby damages of the rotor elements due to electrolytic corrosion are prevented.

Rotor for dynamo electric machine

A shaft torsional vibration monitor for a poly phase turbine generator and its prime mover turbine connected thereto comprises an electrical torque detector detecting electromagnetic torque applied to the turbine generator rotor, a memory unit capable of storing plurality sets of torque variation data due to system disturbances each having an initial torque variation rate more than a predetermined amount, a first processor fetching the sets of torque variation data one by one from the memory unit and determining the corresponding shaft torsional vibration and a second processor determining fatigue and life expectancy of the rotary shaft system for the turbine generator and its turbine by accumulating torsional stresses caused by respective shaft torsional vibrations.

Shaft torsional vibration monitor for a multi-mass rotary shaft system

A superconducting device including a superconducting coil is suitable for use in a nuclear magnetic resonance computer tomography apparatus which requires a highly-uniform, highly-stable magnetostatic field. However, a serious problem arises when a large-sized superconducting coil is to be installed in a small room of a hospital or the like. A superconducting device capable of solving this problem is disclosed in which a very low temperature vessel having the form of a cylinder contains a superconducting coil in a state that the superconducting coil is immersed in a very low temperature coolant, and very low temperature coolant inlet port communicating the very low temperature vessel for introducing the very low temperature coolant into the very low temperature vessel is provided along a radial direction perpendicular to the horizontal center axis of the superconducting device and inclined at a desired angle with a vertical direction. The above superconducting device can be installed in a small room of a hospital, and makes easy a very low temperature coolant introducing operation.

Superconducting device

A cryostat including a horizontal hollow space section of room temperature in which a liquid helium vessel is supported by a plurality of support structures each having a multiple cylinder of small thickness and a liquid nitrogen vessel is supported by a plurality of tension rods.

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Hitachi, Japan

Yasuomi Yagi