TY - JOUR
T1 - Overvoltage Protection of Large Power Transformers - A Real-Life Study Case
AU - Bak, Claus Leth
AU - Einarsdottir, K. E.
AU - Andresson, E.
AU - Rasmussen, J. M.
AU - Lykkegaard, J.
AU - Wiechowski, Wojciech Tomasz
PY - 2008
Y1 - 2008
N2 - This paper demonstrates the results from a detailed study of the overvoltage protection of a particular 400/150-kV 400-MVA power transformer. The work presented here is based on a real-life power system substation design and data and initiated by Danish TSO Energinet.dk as a consequence of serious transformer overvoltage damage. A simulation model for the entire system consisting of overhead line, transformer, surge arrester, and earth grid has been created in PSCAD/EMTDC. The main focus has been put on the earth grid, which has been submodeled in detail in MATLAB using an electromagnetic transient approach based on the thin-wire program made by J. H. Richmond for NASA in 1974. The earth grid model is verified with excellent agreement compared to already published results. The overvoltage performance of the particular case is analyzed, and it shows that the transformers LIWL have probably been exceeded. It is clearly illustrated that the transient performance of the earth grid plays an important role in the overall overvoltage protection system design.
AB - This paper demonstrates the results from a detailed study of the overvoltage protection of a particular 400/150-kV 400-MVA power transformer. The work presented here is based on a real-life power system substation design and data and initiated by Danish TSO Energinet.dk as a consequence of serious transformer overvoltage damage. A simulation model for the entire system consisting of overhead line, transformer, surge arrester, and earth grid has been created in PSCAD/EMTDC. The main focus has been put on the earth grid, which has been submodeled in detail in MATLAB using an electromagnetic transient approach based on the thin-wire program made by J. H. Richmond for NASA in 1974. The earth grid model is verified with excellent agreement compared to already published results. The overvoltage performance of the particular case is analyzed, and it shows that the transformers LIWL have probably been exceeded. It is clearly illustrated that the transient performance of the earth grid plays an important role in the overall overvoltage protection system design.
U2 - 10.1109/TPWRD.2007.905793
DO - 10.1109/TPWRD.2007.905793
M3 - Journal article
SN - 0885-8977
VL - 23
SP - 657
EP - 666
JO - IEEE Transactions on Power Delivery
JF - IEEE Transactions on Power Delivery
IS - 2
ER -