Recent Developments of Electrical Drives - Part 3. The book stating the recent developments of electrical drives, can be useful for engineers and researchers investigating and designing electrical and electronic devices as well as for students and young researchers dealing with electrical and electronic engineering, computer sciences (advanced computer modelling, sophisticated control systems with artificial intelligence tools applied, optimal design bye use of classical and genetic algorithms employed), applied mathematics and all the topics where electromagnetic, thermal, mechanical phenomena occur | I-1. CORE LOSS IN TURBINE GENERATORS ANALYSIS OF NO-LOAD CORE LOSS BY 3D MAGNETIC FIELD CALCULATION A. Nakahara1 K. Takahashi1 K. Ide1 J. Kaneda1 K. Hattori2 T. Watanabe2 H. Mogi3 C. Kaido3 E. Minematsu4 and K. Hanzawa5 Hitachi Research Laboratory Hitachi Ltd. 7-1-1 Omikacho Hitachi Ibaraki 319-1292 Japan anakaha@ takahiko@ 2Hitachi Works Power Systems Hitachi Ltd. 3-1-1 Saiwaicho Hitachi Ibaraki 317-8511 Japan kenichi_hattori@ isao@ 3Steel Research Laboratories Nippon Steel Corp. 20-1 Shintomi Futtsu Chiba 293-8511 Japan mogi@ 4Flat Products Division Nippon Steel Corp. 6-3 Otemachi 2-chome Chiyoda-ku Tokyo 100-8071 Japan 5Yawata Works Nippon Steel Corp. 1-1 Tobihatacho Tobata-ku Kitakyusyu Fukuoka 804-8501 Japan Abstract. Magnetic field analysis of no-load core loss in turbine generators is described. The losses in laminated steel sheets are calculated from the results of finite element magnetic field analysis. The additional losses in metal portions other than the steel sheets are also calculated. The sums of these losses were compared with the measured values for two generators and found to be 88 and 96 of the measured values. The results revealed that the additional losses made up a considerable part of the core losses. Introduction Turbine generators have been developed by using various design technologies to meet the needs of customers. Reliable estimation of losses is essential in designing highly efficient turbine generators 1-3 . Among various losses core loss is one of the most difficult to estimate for two reasons 1. The cataloged data of electrical steel sheets are measured for a rectangular shape in a uniform magnetic field. Electrical steel sheets in an actual machine however are processed into complex shapes and the induced field is not uniform. 2. The measured core loss of a turbine generator seems to include additional losses. One of them is eddy current .
