Identification of three-phase grid impedance in the presence of parallel converters
Luhtala, Roni; Messo, Tuomas; Roinila, Tomi; Alenius, Henrik; Jong, Erik De; Burstein, Andrew; Fabian, Alejandra (2019)
Luhtala, Roni
Messo, Tuomas
Roinila, Tomi
Alenius, Henrik
Jong, Erik De
Burstein, Andrew
Fabian, Alejandra
2019
2674
Julkaisun pysyvä osoite on
https://urn.fi/URN:NBN:fi:tty-201909022052
https://urn.fi/URN:NBN:fi:tty-201909022052
Kuvaus
Peer reviewed
Tiivistelmä
Grid impedance is an important parameter which affects the control performance of grid-connected power converters. Several methods already exist for optimizing the converter control system based on knowledge of grid impedance value. Grid impedance may change rapidly due to fault or disconnection of a transmission line. Therefore, online grid identification methods have been recently proposed to have up-to-date information about the grid impedance value. This is usually done by perturbing the converter output current and measuring the response in output voltage. However, any parallel converters connected to the same interface point will cause errors, since the measured current differs from the current that is flowing through the grid interface point. This paper points out challenges and errors in grid impedance identification, caused by parallel converters and their internal control functions, such as grid-voltage support. Experimental grid-impedance measurements are shown from the power hardware-in-the-loop setup developed at DNV-GL Flexible Power Grid Lab.
Kokoelmat
- TUNICRIS-julkaisut [19020]