Phase-Domain Synchronous Machine Model with Main Flux Saturation for EMTP-type Solution

Representing magnetic saturation in the AC synchronous machine models increases the accuracy of computer studies. Common approaches include considering the saturation along the d-axis only, along the qd axes separately, and along the main flux path. The last approach generally has a better consistency with the experimental results. This paper proposes a new saturable phase-domain (PD) synchronous machine model for the EMTP-type solution utilizing the single-saturation factor to represent the main flux saturation. The proposed PD model incorporates a piecewise-linear function for a numerically-efficient representation of the nonlinear saturation characteristic. Computer studies carried out in PSCAD demonstrate the effectiveness and high accuracy of the new proposed PD model with respect to other existing state-of-the-art saturable synchronous machine models.