Power control system with improved phase control
US5268631A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 6, 1991 |
| Grant date | Dec 7, 1993 |
| Priority date | — |
| Expiry date | Nov 6, 2011 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S323/905
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
An improved phase-controlled power control apparatus includes a semiconductor switching element for varying the effective power delivered to a load from the power lines. The conduction angle of the semiconductor power switch element is varied from a nominal angle to compensate for changes in power line voltage and for changes in load current. The amount of load current flow is continuously compared to the power line voltage to detect any overcurrent condition, even very close to the zero-crossing of the power line voltage. The shape of the transition from load current on to load current off (or vice versa) in controlled to minimize audible noise from the load. The load current can be shared between a plurality of compatible power control sections.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.