Sumários
LL and LLG faults
5 novembro 2015, 11:00 • Luis Marcelino Ferreira
Review of LG fault from abc to dih
Circuit arrangement for LL fault (also from abc to dih)
Circuit arrangement for LLG fault (also from abc to dih)
Role of neutral impedances and fault impedances
Choice of which phases to fault
Duality circuitry: phase a to ground and bc clear and bc to ground and a clear
Voltages and currents
Procedures for computation
Summary of the ideas behind symmetrical component analysis and use of three-phase symmetric analysis
Symmetrical components and LG short circuit
3 novembro 2015, 09:30 • Luis Marcelino Ferreira
Symmetrical components and LG short circuit
Review of Symmetrical components (Fortescue transformation)
Basis (d,i,q),
Diagonlization of Zabc
Modelling of a generator in dih
LG short-cricuit Ia=Ea/Za
How to compute Za in dih
Traditional approach to get the series circuit arrangement of dih circuits
The role of Zn, derivation of formulas
Three Thevenin equivalents
Special case of h circuits
Example for a YY transformer