Prediction of steady state: Performance of a linear induction motor from static tests

A testing procedure that yields the parameters of a linear induction motor (LIM) equivalent circuit has been developed. A test facility was designed and constructed to carry out the experiments. Both 60 Hz sinusoidal and variable frequency PWM experiments were performed. Equations were developed to determine parameters of the LIM equivalent circuit from the instantaneous voltage and current waveforms measured at the terminals of the machine during the tests. The referred secondary leakage reactance X{dollar}sb2spprime{dollar}, is found to affect thrust prediction significantly. A theoretical derivation of this parameter was implemented. Experimentally, it was found that the parameter values of the equivalent circuit vary with operating condition. A LIM simulation model was developed which uses an equivalent circuit whose parameters are functions of frequency using linear regression. A longitudinal end effect factor proposed by Duncan (23) was implemented in the equivalent circuit model, and the thrust degradation due to the longitudinal end effect was quantified. The thrust and normal force predictions of the equivalent circuit model were close to the analytical results obtained from an electromagnetic layer model and the finite element method. This thesis shows that a series of static tests on a LIM can provide useful information about the steady state performance of the machine.