Protective relay system provided with difference and addition filters
US5796630A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 19, 1996 |
| Grant date | Aug 18, 1998 |
| Priority date | — |
| Expiry date | Jul 19, 2016 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02H3/44
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A protective relay system detects a first electric variable and a second electric variable of a power system to discriminate in a time series whether or not a fault portion of a line or equipment included in the power system exists within a predetermined range, so as to determine whether protection of the power system should be carried out. The system includes a digital filter for outputting a first difference electric variable data indicative of a difference between at least two sample data of plural sampling data of the first electric variable and a difference between at least two sample data of plural sample data of the second electric variable at plural sampling times of the time series. The system also includes an addition filter for outputting first and second additive electric variable data indicative of orthogonal vector data with respect to the first and second difference electric variable data. The system further includes a relay control unit for calculating controlled variables of a relay operation in the power system on the basis of the first and second difference electric variable data at a certain sampling time, so as to judge whether or not protection of the power sy…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.