Journal article · Ahead of Print article
Voltage stability assessment accounting for non-linearity of Thévenin voltages
This study presents a new method that overcomes the limitations of previous Thévenin equivalent methods used for detecting voltage instability. The new method determines the maximum deliverable power to a load by accounting for the nonlinearity of the Thévenin voltage seen from a load. The developed algorithm computes Thévenin equivalents seen from voltagecontrolled and non-controlled nodes to determine how much load changes influence the contributing generators to a load.
The algorithm computes an active load margin which gives information about the distance to instability. Tests are performed on the modified Nordic32 system, where the on-load tap changer mechanism of transformers was the driving force causing voltage instability that leads to small-signal rotor angle instability.
The results demonstrate that the proposed method accurately detects voltage instability compared to the method based on the Thévenin impedance matching criterion, which first detects instability when the system conditions have crossed the critical boundaries.
| Language: | English |
|---|---|
| Publisher: | IET |
| Year: | 2020 |
| Pages: | 3338-3345 |
| ISSN: | 17518695 and 17518687 |
| Types: | Journal article and Ahead of Print article |
| DOI: | 10.1049/iet-gtd.2019.1774 |
| ORCIDs: | Karatas, Bahtiyar C. , Jóhannsson, Hjortur and Nielsen, Arne Hejde |
Thévenin impedance matching criterion Thévenin voltage active load margin developed algorithm computes Thévenin equivalents load changes maximum deliverable power nonlinearity on load tap changers power system control power system dynamic stability power system security power system stability previous Thévenin equivalent methods rotors small-signal rotor angle instability voltage control voltage instability voltage stability assessment accounting voltage-controlled
