04912378 is referenced by 66 patents and cites 2 patents.

A system for determining rotor position information from the back emf of a permanent magnet motor includes extracting the third harmonic from the back emf of the motor by summing the terminal voltages of the motor. The phase angle of the third harmonic of the back emf is a function of the position of the rotor, and a signal is produced when the phase angle of the third harmonic (measured with respect to the voltage on the neutral conductor of the motor) reaches a predetermined angle. Electronically controlled switches selectively apply power to the phase windings of the motor in response to the detection of predetermined phase angles of the third harmonic.

Title
Third harmonic commutation control system and method
Application Number
7/222556
Publication Number
4912378
Application Date
July 21, 1988
Publication Date
March 27, 1990
Inventor
Slobodan N Vukosavic
Beograd
YU
Agent
Polster Polster and Lucchesi
Assignee
Emerson Electric Co
MO, US
IPC
H02K 29/06
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