Constant-Parameter Discretized State-Space Model of Saturable Induction Machines for Fixed Time-step Simulations

Design and analysis of today's power systems are highly dependent on various simulation programs and platforms (including real-time FPGA-based hardware-in-the-loop simulators), that require accurate and numerically efficient models of all power system components. Induction machines are widely used in power systems and have numerous well-documented qd-models in the literature that also include magnetic saturation. However, such models are nonlinear and generally, when discretized, will have variable parameters, which makes their use costly in transient simulation studies of large-scale power systems. This paper proposes a constant-parameter discretized qd state-space model for induction machines including the main flux saturation. The presented formulation achieves constant-parameters, and therefore, the proposed model is shown to have superior numerical efficiency with minimal compromise in numerical accuracy. It is envisioned that the presented model may be a suitable for large-scale power systems studies in simulators with small time steps.