Analysis of Conditions for Low Voltage Regulation of Interior-Type Permanent Magnet Alternator

According to phasor analysis of the interior-type permanent magnet alternator with resistive load, the conditions for zero and negative voltage regulation are derived including stator resistance. In the meantime, the range of the corresponding resistive load is obtained. The variation of the voltage regulation with the machine parameters is summarized. A low voltage regulation PM alternator is designed by finite element method combined with magnetic-equivalent-circuit method. The saturated armature reactance and the voltage regulation are determined by using loading magnetic fields. The computation and measurement show that the theoretical analyses are correct, which offers the foundation and effective method for the design of the PM alternator with zero or negative voltage regulation at rated load.