Design of 400 Hz saturistor motors with improved starting performance

A method is presented for predicting, from physical design data, the performance of saturistor induction motors having idle bars of permanent magnet material in the rotor slots. It is shown how the analysis may be used to synthesise the physical design of a motor in order to achieve a specified starting performance. The procedure is applied to the design of a 400 Hz aircraft motor to obtain reduced starting current compared with an original cage motor, without significant detriment to its normal running performance. Measured B-H loop data is presented for Alcomax III, Hycomax III and Hycomax IV materials. Test results demonstrate the validity of the treatment and the success of an experimental design incorporating bars of Hycomax III.