Resonant commutation system for exciting a three-phase alternator
US8773080B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Dec 16, 2010 |
| Grant date | Jul 8, 2014 |
| Priority date | — |
| Expiry date | Aug 18, 2032 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02P9/302
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
An alternator has a field coil that produces a magnetic field which induces electricity in an coil arrangement. A field coil excitation system includes a generator with an output coil assembly for producing alternating electricity. A rectifier converts the alternating electricity into voltage and direct current at two nodes. A capacitor, between the nodes, has capacitance that forms a resonant circuit with inductance of the output coil assembly. Due to that resonant circuit, the voltage and direct current oscillate in a predefined phase relationship. A switch and the field coil are connected in series between the nodes. A controller renders the switch conductive for a time period specified by a received control signal. The switch is rendered non-conductive at the first occurrence of a minimum current level after the time period ends. The predefined phase relationship enables the minimum current level to be detected by sensing the voltage.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.