Feng, F. and Pal, D., "Power Density of Multi-Purpose Motor Controllers - Challenge Beyond Switches," SAE Technical Paper 2016-01-2012, 2016, doi:10.4271/2016-01-2012.
There are many identical large solid-state switching Multi-Purpose Motor Controllers on board of one of the More Electric Aircrafts (MEA). The controllers drive over twice as many different machines with wide torque and speed ranges. The common motor controllers are installed in a central location. The machines are located at diverse and distant positions. Power is delivered and routed from the controllers to machines via a large network comprising of unshielded feeders and multiplexing units. The controllers are required to produce sine wave voltage output to machines, and draw clean power from the source to meet Power Quality (PQ) and Electromagnetic Interference (EMI) requirements. There are significant aircraft level weight savings with that concept. However, designing such a clean motor controller was a major power density challenge beyond switches, accounting for high torque main propulsion engine start and high speed Cabin Air Compressors.