Starting winding optimization in single-phase induction motor design

This paper presents algorithms for the optimal design of the starting winding and/or the starting capacitor for split-phase motors and capacitor start motors by optimizing the starting performance. By means of the circle diagram, the two-dimensional optimization problem becomes a one-dimensional problem. For capacitor start and run motors, two strategies are introduced for the design of the auxiliary winding, the running capacitor, and the starting capacitor. Strategy A designs the auxiliary winding and the running capacitor at the rated operation first, and then optimizes the starting capacitor to achieve the best starting performance. Strategy B optimizes the auxiliary winding and the starting capacitor to achieve the best starting performance first, and then optimizes the running capacitor to get the best rated performance. As an illustration example, the optimal designs of a 400V, 4-pole, 40kW capacitor start and run motor based on these two strategies are provided and compared. The conclusion is that strategy B brings a better design.