A Comprehensive Review on the End Effects of Linear Permanent Magnet Machines

This article presents a literature review of relevant contributions found in the literature concerning the end effects with a focus mainly on linear permanent magnet synchronous machines. Additionally, it presents a classification of the obtained information to classify the end effects and provides essential information for understanding, categorization, modeling, mitigation, and control of the end effects. The causes and consequences of the end effects are also addressed according to the geometrical structure of the linear machine, and the main approaches for end effects modeling are discussed. Also, several existing techniques for mitigation of consequences of end effects are presented, considering changes in the machine geometry or the electromagnetic structure and electronic compensation using control techniques. The control of linear machines accounting for end effects and compensation to achieve better performance to mitigate adverse impacts on machine characteristics are also addressed.