Three-phase distribution transformer connections modeling based on matrix operation method by phase-coordinates

Abstract This paper proposes a matrix operation method for modeling the three-phase transformer by phase-coordinates. Based on decoupling theory, 12 × dimension primitive admittance is obtained at first employing coupling configuration of windings. Under condition asymmetric magnetic circuits, according to boundary conditions connections, transformers in different connections enable be from matrix. Another purpose this explain differences phase-coordinates and positive sequence parameters impedances transformers. The numerical testing results IEEE-4 system show that proposed valid efficient.