Recent Developments of Electrical Drives - Part 36. 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 | . RECENT ADVANCES IN DEVELOPMENT OF THE DIE-CAST COPPER ROTOR MOTOR . Brush . Peters2 . Cowie2 M. Doppelbauer3 and R. Kimmich3 1BBF Associates 68 Gun Club Lane Weston MA 02493 USA ebrush@ 2Copper Development Association Inc. 260 Madison Avenue New York NY 10016 USA dtpeters@ jcowie@ 3SEW Eurodrive GmbH Co KG Ernst-Blickle Str. 42 D-76646 Bruchsal Germany Abstract. Performance of several motors where copper has been substituted for aluminum in the rotor squirrel cage is reported. Copper rotor motors die cast in India for agri-pumping were dynamometer and field tested. Copper rotors resulted in higher electrical energy efficiency slightly higher rotational speed lower operating temperature and higher pumping rates and volume pumped per unit of input energy. SEW-Eurodrive motors with copper rotors are also described. A kW motor with copper simply substituted and a kW motor with redesigned rotor and stator are described. The copper rotor reduced losses in all major categories. Full-load efficiency was increased and percentage points respectively. Finally a study to minimize formation of large pores in die-cast rotors is summarized. Introduction At ICEM 2002 we reported on the performance of motors with die-cast copper rotors. Rotor I2R losses were reduced by 29 to 40 and motor total losses were reduced by 11 to 19 resulting in increased motor efficiencies of no less than percentage points. In this paper motor test data for another group of motors where copper has been directly substituted for the aluminum in the rotor are reported. These copper rotors were die cast in India and motors built and tested by several motor manufacturers there. In the two years since the last ICEM conference important advances have been made in designing and optimizing the rotor and the entire motor to properly utilize the higher electrical .