Method and apparatus for detecting islanding conditions of a distributed grid
US9331486B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 5, 2012 |
| Grant date | May 3, 2016 |
| Priority date | — |
| Expiry date | Dec 29, 2034 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02J3/388
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
An exemplary method and apparatus for detecting islanding conditions of a distributed grid are disclosed, wherein transfer of power through a power electrical unit is controlled on the basis of a control reference. The apparatus includes a first stage and a second stage performing a respective portion of the method. The first stage injects a reactive component to the control reference, and, for at least one electrical quantity of the grid, determines a change in the quantity induced by the injected component, and determines, on the basis of the change in the electrical quantity, whether to move to the second stage of the method. The second stage, for at least one electrical quantity of the grid, determines a value of the electrical quantity, forms a positive feedback term using at the determined value adding a positive feedback term to the control reference, determines a change in an electrical quantity induced by the feedback term, and determines islanding condition on the basis of the change in the quantity induced by the feedback term.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.