| Kenichi Hattori | Power Electric Machine Design Dept., Power & Industrial Systems Div., |
| Kazumasa Ide, Dr. Eng. | Fifth Dept., Systems Research, Hitachi Research Lab., |
| Fumihiko Goto | Consulting Engineering Dept., Hitachi Engineering Co., Ltd. |
| Akitomi Semba | Generator Design Engineering Sec., Power Electric Machine Design Dept., Generator Systems Div., Power and Industrial Systems, |
| Takashi Watanabe, Dr. Eng. | Generator Systems Div., |
Hitachi, Ltd. has developed a 250-MVA (50/60 Hz) large-capacity, air-cooled generator. This is a high-efficiency air-cooled generator that makes maximum use of an ICVS (inner cooler ventilation system). Its performance has been evaluated by embedding ventilation, temperature, and stress sensors at more than 1,000 points in the machine for taking measurements, and the data so obtained has been applied to the construction of a database for designing future hydrogen-cooled and air-cooled generators. The developed generator was found to satisfy class-B temperature-rise standards of the American National Standards Institute (ANSI) for stator and rotor temperature and to achieve a level of efficiency in excess of 98.8%. In the design of this 250-MVA generator, a number of tools for analyzing large-scale loss, ventilation, temperature, and vibration intensity were prepared, and an appropriate generator structure was determined after conducting a survey of several hundred parameters. The suitability of these tools was also evaluated by actual measurements on this generator.
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The Hitachi Hyoron (Japanese Only) |
turbo-generator, armature, air, circulating-current, cooling
