Seminar 2 - Selective Fault Detection Methods for MTDC Grids

Abstract:

The increased demand for renewable energy generation requires higher flexibility of transmission systems. This requirement together with technical progress in high-voltage direct-current (HVDC) technology have resulted in the ambition to build large-scale multi-terminal DC (MTDC) grids. These large-scale MTDC grids are expected to require fast DC breakers which allow for selective fault clearing. Selective fault clearing strategies avoid decreased availability during faults because only the faulted part can be isolated whereas the healthy part continues operation. For successful operation of a MTDC grid with multiple breakers, a protection system with selective fault detection is thus required such that the DC breakers achieve correct fault isolation in the event of a fault. Selective fault detection in MTDC grids is however not trivial because of low impedance characteristics and short required isolation times. In this seminar, previously suggested selective fault detection methods for protection of a MTDC transmission system using DC breakers are summarized and their implementation in a physical, RTDS-compatible, HVDC protection IED is presented.

Bio:

Ilka Jahn is a PhD student at Power Electronics research group, KTH. She received the M.Sc. degree in electrical engineering from RWTH Aachen University, Germany, in 2015. Her current research interests include HVDC protection.