Measurement of Unified Admittance Model for Three-Phase System by Two-Phase Excitation

This paper proposes a unified admittance measurement method for a three-phase system which is described in the stationary or in the synchronous domain only by two-phase excitation with sinusoidal waveforms in positive and negative frequency components. There are frequency couplings in the two components when the system is asymmetric. A measurement method that scans for a desired frequency range is proposed. It is based on two-phase voltage application and response current measurement processes at coupling frequencies. Two applications examples, a resistive-inductive (RL) circuit and an IPM motor in a respective domain, are investigated to validate the proposed measurement method for unified admittances.