System for reducing harmonics by harmonic current injection
US5499178A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Feb 10, 1994 |
| Grant date | Mar 12, 1996 |
| Priority date | — |
| Expiry date | Feb 10, 2014 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02P90/40
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A circuit is provided for generating a current that is a harmonic of the frequency of the utility system and which is of a selected amplitude and phase to reduce the total harmonic distortion of a system that converts alternating current to direct current, or vice versa. The DC signal is sampled and by controlling switches, a sinusoidal current at the desired harmonic is generated, and is provided to a neutral of a transformer that injects this current into the multiphase AC system used by the utility in a very low cost, easily controlled, and highly effective manner. In a second embodiment, the injection current is provided to a common junction of a magnetic device.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.