An efficient and accurate method of representing magnetic saturation in physical-variable models of synchronous machines

When analyzing machine/converter systems it is convenient to represent the stator variables in physical (abc) form. It has been shown that a physical-variable voltage-behind-reactance form of the synchronous machine model can be derived which is numerically more efficient than existing physical-variable models. In this research, a new voltage-behind-reactance model is derived which incorporates the effects of magnetic saturation. This model is shown to have the same numerical efficiency of the unsaturated model and is readily implemented in either circuit-based or differential-equation based simulation languages. An example system is provided which demonstrates the accuracy and efficiency of this model for a wide-range in operating conditions.