Analysis of salient-pole permanent magnet linear synchronous motors using a unified integrity analytical method

Salient-pole permanent magnet linear synchronous motors (SP-PMLSMs) offer significant advantages over other permanent magnet linear motor topologies, in terms of force density and high speed operation, for example. However, due to the relative complexity of their salient-pole structure, theoretical research on SP-PMLSM´s has, to date, been very limited. In this paper, both of those new approaches, called salient-pole PM equivalent with double sheet current (SPM-EDSC) and the secondary salient-pole structure equivalent with anisotropic body salient-pole PM equivalent (SPS-EAB), are presented. The actual PMs excitation field sources and salient pole structure can be effectively replaced by SPM-EDSC and SPS-EAB. The 2-D unified integrity analytical model and theory of SP-PMLSM are established here. The key difficult problems in theory and application for SP-PMLSM are solved simply and effectively. There is no longer limit and trouble on d-q axis that often is used in conventional rotary motor. The analytical methods for both the salient pole and the nonsalient pole motor are completely unified. It only takes several seconds for 2D integrity analysis on ordinary P II PC and very simple data input preprocessing. Enormous novel analytical results of electromagnetic field distribution, characteristic, measurement results of SP-PMLSM and important conclusions are obtained for the first time. A wavelet method is adopted very well in postprocessing of analytical and measurement results.