Modeling of Synchronous Machine in Phase Domain With Constant Inner Impedance Based on Frequency Shifting Theory

Abstract

As the principal source of the electric energy in power systems, the modeling of the synchronous machine for transient analysis has always been an active topic of research. In this paper, a new synchronous machine model for the simulation of multi-scale transients is developed in the phase domain. Based on the Hilbert transform and the reference frame transformation, the machine equations are reconstructed through the analytic signals. The shift frequency appears as a new simulation parameter in addition to the time-step size. By adding an artificial damper winding, a constant machine admittance matrix is formed. The proposed model provides a direct network-machine interface. Through appropriate selection of time step size, shift frequency, and artificial winding parameters, the proposed model supports accurate and efficient simulations for both the high-frequency and low-frequency transients within a simulation run. The proposed model is compared with traditional electromagnetic transients program (EMTP) type models. Case studies demonstrate the effectiveness of the proposed machine model in terms of accuracy and efficiency.