The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Dec. 23, 1997
Filed:
Oct. 27, 1995
Gary E Horst, Manchester, MO (US);
Alan P French, Florissant, MO (US);
Emerson Electric Co., St. Louis, MO (US);
Abstract
A polyphase dynamoelectric machine (10) such as a switched reluctance motor has a stator assembly (12) and a rotor assembly (14). The rotor assembly is movable with respect to the stator assembly. The stator assembly includes a stator (16) having a plurality of stator poles (18). The rotor assembly includes a rotor (20) having a plurality of rotor poles (22). The stator assembly further includes a plurality of separately energizable stator windings (24) associated with the respective machine phases. These stator windings are energized and de-energized in a predetermined sequential manner to sequentially activate and deactivate the machine phases. Energization and de-energization of the respective stator windings is at least partially determined as a function of the machine's instantaneous rotor position. The machine includes a processor (26) for determining the rotor position. The processor monitors the waveform of a circulating current coupled from an energized stator winding for an active machine phase into a de-energized stator winding for an inactive machine phase. Respective energized and de-energized stator windings are interconnected to form a closed circuit path by which the current in the energized stator winding is coupled into the de-energized stator winding. Monitoring the resultant current waveform provides an indication of rotor position, and the processor uses this information to energize and de-energize the stator windings.