04712050 is referenced by 94 patents and cites 8 patents.

A control system for brushless DC motors detects counter electromotive force voltages induced in motor windings and produces rotor position detection signals from the counter electromotive force voltages. The maximum value of an input DC current to a motor drive circuit is held and the phase of the rotor position detection signals is changed in accordance with the held value of the input DC current to prevent the phase of the position detection signals from varying with the load on the brushless DC motor.

Title
Control system for brushless DC motor
Application Number
7/9290
Publication Number
4712050
Application Date
January 30, 1987
Publication Date
December 8, 1987
Inventor
Susumu Kashiwazaki
Utsunomiya
JP
Toru Inoue
Tochigi
JP
Kiyoshi Nagasawa
Tochigi
JP
Agent
Antonelli Terry & Wands
Assignee
Hitachi
JP
IPC
H02K 29/06
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