Patent · US Expired

Method and apparatus for controlling a motor

US4743824A · kind A · utility

7Cited by
4References
18Claims
0Family size

Assignee

Inventor

Key dates

Filing dateFeb 6, 1987
Grant dateMay 10, 1988
Priority date
Expiry dateFeb 6, 2007

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH02P8/22
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

The invention relates to a method and apparatus for controlling the current (I1, I2) through a stator winding (L1, L2) of a motor (M) which is supplied with energy from a voltage source (V) via a drive circuit (DL1, DL2). The drive circuit is controllable such as to provide at least three different operational states, of which a first normally signifies increasing or maintained magnitude of the current, a second normally signifies shutting down or decreasing the current comparatively slowly and a third operational state normally signifies shutting down or reducing the current comparatively rapidly or at least quicker than in the second operational state. In a method and apparatus in accordance with the invention the desired value time sequence is sensed, and at least the possibility of control so that entry into the third operational state is limited in time in response to the result of sensing the desired value time sequence. The method and apparatus are primarily intended for micro-stepping of a two-phase stepping motor with permanently magnetized rotor.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.