Investigations into Performance Aspects of Field Aligned Starting

Three-phase cage induction motors can be started on single-phase supply lines by field aligned starting (FAS) with minimal inrush currents. FAS is a technique that generates a high impulse-like torque to start a motor independent of the mains supply, before connecting the already spinning motor to the mains to operate in a standard Steinmetz connection. A dynamic model and parameter estimation method for FAS have previously been presented and experimentally validated. As the starting performance of FAS is largely governed by the values of a small number of key variables, this paper utilizes the dynamic model to investigate both the functionality and the impact of these variables on the starting performance. The results of the investigation suggest that the proper choice variable values is critical to a successful FAS design, and that the FAS model could effectively be used as a design aid to achieve improved FAS starting performance.