Title :
Simplified three-phase transformer model for electromagnetic transient studies
Author :
Chimklai, S. ; Marti, J.R.
Author_Institution :
British Columbia Univ., Vancouver, BC, Canada
fDate :
7/1/1995 12:00:00 AM
Abstract :
This paper presents a simplified high-frequency model for three-phase, twoand three-winding transformers. The model is based on the classical 60 Hz equivalent circuit, extended to high frequencies by the addition of the winding capacitances and the synthesis of the frequency-dependent short-circuit branch by an RLC equivalent network. By retaining the T-form of the classical model, it is possible to separate the frequency-dependent series branch from the constant-valued shunt capacitances. Since the short-circuit branch can be synthesized by a minimum-phase-shift rational approximation, the mathematical complications of fitting mutual impedance or admittance functions are avoided and the model is guaranteed to be numerically absolutely stable. Experimental tests were performed on actual power transformers to determine the parameters of the model. EMTP simulation results are also presented
Keywords :
digital simulation; equivalent circuits; numerical stability; power engineering computing; power system transients; power transformers; software packages; transformer windings; 60 Hz; EMTP; RLC equivalent network; T-form; computer simulation; electromagnetic transient studies; equivalent circuit; frequency-dependent short-circuit branch; high-frequency model; minimum-phase-shift rational approximation; numerical stability; power transformers; three-phase transformer model; winding capacitances; Admittance; Capacitance; Circuit synthesis; Electromagnetic modeling; Equivalent circuits; Frequency synthesizers; Impedance; Mathematical model; Network synthesis; Phase transformers;
Journal_Title :
Power Delivery, IEEE Transactions on