Semiconductor electric motor having a rotary transformer to excite a rotor
US4698563A · kind A · utility
Inventor
Key dates
| Filing date | Dec 16, 1986 |
| Grant date | Oct 6, 1987 |
| Priority date | — |
| Expiry date | Dec 16, 2006 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02P6/14
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A m-phase semiconductor electric motor comprises an rotary transformer to excite a rotor; a shaft and a bearing for rotatably supporting the rotor; an exciting coil for exciting the rotor magnetic poles; the rotary transformer includes a first and a second soft-ferrite core having magnetic paths and arranged to rotate relative to each other, the first core is coupled to the rotor shaft, the second core is fixed to the motor housing, a primary and a secondary coil are mounted on the second and first cores, respectively; the motor further comprises an oscillator for supplying the primary coil with a high frequency current; an electric circuit for rectifying the output of the secondary coil to energize the exciting coil; a fixed armature having m-phase coils; position detecting means for generating rotor position signals, each of the rotor position signals having positive and negative portions alternating every 180 degrees electrical angle; means for providing a reference voltage for commanding output torque; a multiplier circuit for multiplying the position detecting signal; an armature current detecting circuit for detecting armature current; an armature current control circuit for …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.