Rotating Power Electronics for Electrical Machines and Drives - Design Considerations and Examples

The industrial shift towards rotating power electronics (RPE) promotes brushless flexible rotor excitation, as well as battery-less rotor instrumentation and measurement devices for electrical machines. Recently, the high-power thyristor converter has been proven to be excellent for rotating applications. Moreover, MOSFET components have been successful for low-power rotating applications. However, the question arises whether IGBT's, capacitors and related components are able to withstand the centrifugal forces that are generated due to shaft rotation. In fact, the manufacturers do not conventionally test their power electronic components against cyclic accelerational forces. Moreover, the insulation material in some types of semiconductor modules are viscous and will be affected by rotational forces. This paper addresses the current design challenges and presents new design criteria for RPE systems and applications. Finally, this paper reviews the current technology status for RPE concepts.