Current differential protection method for self-adaptive half-wavelength line based on time-difference method
US10985547B2 · kind B2 · utility
Assignees
Inventors
Key dates
| Filing date | Jul 11, 2016 |
| Grant date | Apr 20, 2021 |
| Priority date | — |
| Expiry date | Apr 10, 2037 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02H3/305
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A current differential protection method for a self-adaptive half-wavelength line based on a time-difference method. Since an electrical distance of half-wavelength power transmission is long, after a fault occurs, there is an obvious time difference between the actuation times for protecting starting elements at two sides of a line. According to the principles of wave propagation, the position of a fault point can be determined by means of a difference between the actuation times for protecting the starting elements at the two sides of the line. By means of taking the fault point as a differential point, a current value at the differential point can be obtained according to a long line equation by means of the voltage and current at protection-mounted positions at the two sides of the line, and a differential current is then calculated.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.