Conference paper
Estimating the short-circuit impedance
Electric Power Engineering, Department of Electrical Engineering, Technical University of Denmark1
Department of Electrical Engineering, Technical University of Denmark2
Mathematical Statistics, Department of Informatics and Mathematical Modeling, Technical University of Denmark3
Department of Informatics and Mathematical Modeling, Technical University of Denmark4
A method for establishing a complex value of the short-circuit impedance from naturally occurring variations in voltage and current is discussed. It is the symmetrical three phase impedance at the fundamental grid frequency there is looked for. The positive sequence components in voltage and current are derived each period, and the short-circuit impedance is estimated from variations in these components created by load changes in the grid.
Due to the noisy and dynamic grid with high harmonic distortion it is necessary to threat the calculated values statistical. This is done recursively through a RLS-algorithm. The algorithms have been tested and implemented on a PC at a 132 kV substation supplying a rolling mill. Knowing the short-circuit impedance gives the rolling mill an opportunity to adjust the arc furnace operation to keep flicker below a certain level.
Therefore, the PC performs a simultaneously measurement of impedance and flicker.
| Language: | English |
|---|---|
| Publisher: | UMIST |
| Year: | 1997 |
| Pages: | 453-457 |
| Proceedings: | 32'nd Universities Power Engineering Conference, UPEC'97 |
| Types: | Conference paper |
| ORCIDs: | Nielsen, Arne Hejde and Poulsen, Niels Kjølstad |
