Saturable analysis of reversing shaded-pole motors
This thesis is concerned with the analysis of reversing shaded pole motors. Chapter two develops a saturable finite-element analysis for induction machines which includes the effects of rotor harmonics and rotor skew. The analysis consists of two iterative schemes. Firstly, the Newton-Raphson algorithm is used to provide the solution of the nonlinear field problem in which the current sources and potentials are complex. A second minimisation process ensures that the terminal conditions are satisfied and provides, therefore, the output characteristics of the motor. Finally, some technical details concerning computer implementation of the method are discussed.In chapter three, the analysis is applied to a shaded-pole motor operating, in the first instance, with reduced rotor end-rings, in the second, with full end-rings. The predicted performance characteristics of the machine are compared with those determined experimentally, to indicate the validity of the method.Chapter four represents a discussion on some practical aspects of the application of the analysis.Chapter five provides some suggestions for further improvement of the technique and also indicates the scope for future work.