DC power flow can be controlled though N-1 different DC lines/cables in a DC grid having N individual AC/DC converters. A large meshed DC grid can have more DC lines, and since we can not control power in all lines/cables, an overload may result. In this paper, two methods are proposed for DC power flow control through DC lines/cables. The first method involves using extra resistors embedded in series with DC lines/cables and switched by mechanical or semiconductor based DC circuit breakers. The other method includes installing DC/DC converter at one of the DC line/cable ends with the purpose of DC power flow control. It is shown that the first approach suits better for a short transmission line/cable, while the second one is proposed for a long transmission line/cable with high rated current and higher voltage drop. PSCAD simulation results are presented for a half bridge bidirectional DC chopper employed for DC power flow control between two large 370kV DC grids.
|Title of host publication||AC and DC Power Transmission (ACDC 2012), 10th IET International Conference on|
|Number of pages||6|
|Publication status||Published - Dec 2012|
|Event||IET ACDC 2012 Birmingham, December 2012 - , United Kingdom|
Duration: 4 Dec 2012 → 7 Dec 2012
|Conference||IET ACDC 2012 Birmingham, December 2012|
|Period||4/12/12 → 7/12/12|