AC drive with optimized torque

Year	Description
1991	Invention patented by Eric J. Stacey on May 31th, 1991. Abstract: Apparatus to extend the speed range and maximize torque of an ac drive by optimizing the torque angle as a function of speed. Using the back-emf of the machine, or the voltage from a permanent magnet generator mounted on the mtor shaft for reference, a novel analog biasing arrangement of a fast tracking multi-phase phase locked loop generates a set of stator current reference signals having a phase angle which is programmed to provide the optimum torque angle at any speed.
Source: selected by the editor from original sources.

Invention: AC drive with optimized torque