Dynamic phasor modeling of doubly-fed induction machines including saturation effects of main flux linkage

Power system simulation has become an integral part of power system planning, design and study today. Due to the vast array of power system disturbances that occur and the speed of their respective dynamics, simulation tools have traditionally been split into two types; Transient Stability type programs (TSP) and Electromagnetic Transient type programs (EMTP). Several papers have been written and solutions have been proposed to come up with a solution that would combine these two different types of programs into one simulation tool that can be used to simulate both the slow electromechanical transients and fast electromagnetic transients that occur on power systems. One such method that has been proposed and is showing promising potential for unified power system simulation is the concept of dynamic phasors. The dynamic phasor concept extends the traditional concept of steady state phasor representation used extensively in TSP programs by allowing these phasor quantities to change with time during transient events. This thesis focuses on the modeling of induction machines using the dynamic phasor concept. Several induction machine models have already been proposed using the dynamic phasor concept however none of which take into account the effects of saturation that often occurs during induction machine operation. This thesis therefore focuses specifically on modeling the effects of main flux linkage saturation in induction machines using the concept of dynamic phasors. The proposed model is based on the flux correction method and extends this concept to representation in dynamic phasor quantities. This is done by first verifying the consistency of the unsaturated dynamic phasor induction machine model against well known conventional models and then implementing the proposed dynamic phasor saturation model and again verifying it’s consistency with conventional saturation model of the induction machine. The results obtained in this thesis show that the proposed saturation model using the dynamic phasor concept is consistent with conventional saturation models with reasonable accuracy and efficiency and therefore provides a good starting point for further research in machine saturation modeling using the dynamic phasor concept.Applied Science, Faculty ofElectrical and Computer Engineering, Department ofGraduat