Method and apparatus for controlling the rotational speed and phase of synchronous motors

US4418307A · kind A · utility

Assignee

• The Braun Corporation · DE

Inventors

• Harald Hoffmann · Much, DE
• Dan-Corneliz Raducanu · Eberbach, DE

Key dates

• Filing date: Sep 16, 1980
• Grant date: Nov 29, 1983
• Expiry date: Sep 16, 2000

Classification

• Technology area (CPC G): Physics
• CPC primary: G04C15/0036
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

A method and apparatus for controlling the rotational speed and phase of a synchronous motor is provided by sensing the motion of the poles with respect to the stator to provide sensor signals. The sensor signals are converted to sensor pulses and compared to constant pulses. Driving pulses are generated so that if the poles run ahead, a braking moment is generated, and if the poles lag behind, an accelerating moment is generated.