Matching overcurrent characteristic curves
US5856903A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Nov 12, 1997 |
| Grant date | Jan 5, 1999 |
| Priority date | — |
| Expiry date | Nov 12, 2017 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02H3/0935
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A method for configuring a digital overcurrent relay to provide a plurality of selectable time overcurrent characteristic responses corresponding to a plurality of target curves. According to one embodiment, a template curve is selected from the plurality of target curves, and a scaling factor is generated for each remaining target curve, wherein the relay comprises means for generating approximated curves from a given template curve and a given scaling factor. It is determined whether each approximated curve is within a threshold amount of total error with respect to its corresponding target curve. If any approximated curves are above the threshold amount, then a further template is selected from the plurality of target curves, and scaling factors are again generated and adjusted for the further template curve, until no approximated curves are above the threshold amount.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.