Donald Wayne Novotny
Donald W. Novotny’s insight into the complex behavior of alternating current (ac) machines enabled the motor drive technology revolution. By developing a basic understanding of the unexpected nature of machine dynamics over a range of frequencies, he clarified the nature of these responses, showing they were inherent in all induction machines. This resulted in the ability to evaluate individual machines to determine the global influence of specific machine parameters and to predict general trends over an entire range of machine ratings. This work was the first to demonstrate the strong influence of magnetic saturation on dynamic response as well as on self-excitation in induction machines.
He published one of the first papers on hysteresis control of current in an ac motor drive, now a standard technique for current control. Another of his papers was on the impact of bearing currents in inverter drives and a proposed method for analyzing the phenomenon. More recently he introduced and analyzed the coaxial winding transformer as a means of drastically reducing leakage inductance, thus extending the frequency range of many power electronic circuits.
An IEEE Life Fellow, Dr. Novotny is an emeritus professor at the University of Wisconsin, Madison.