04162435 is referenced by 73 patents and cites 38 patents.

Method and apparatus for electronically commutating a direct current motor is disclosed not requiring position sensors but rather sampling induced voltage across an unenergized motor winding to derive control signals therefrom. One motor winding is energized while the voltage across another winding is sampled and integrated to provide a flux indication. The integrated voltage sample is compared to a reference and when that integrated value exceeds the reference, the next winding of the motor is enabled and the voltage integral returned to an initial value. A ring counter maintains an indication of the currently energized winding and may also be employed to cause the sampling circuit to sample the induced voltage on the winding next in the motor sequence to be energized.

Title
Method and apparatus for electronically commutating a direct current motor without position sensors
Application Number
5/729804
Publication Number
4162435
Application Date
October 5, 1976
Publication Date
July 24, 1979
Inventor
Floyd H Wright
Fort Wayne
IN, US
Agent
A Burgess Lowe
Ralph E Krisher Jr
Assignee
General Electric Company
IN, US
IPC
H02P 7/00
H02K 29/00
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