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In this paper, the detent force caused by the end effect in a flux-switching permanent magnet linear motor (FSPMLM) with 6 slots and 5 poles is investigated and reduced by two different methods. Firstly, the detent force is diminished by adjusting the position of end teeth of primary side and injecting compensation current into compensation windings wound around the end teeth. Based on the linear relationship between compensation current and compensation force, the proper compensation current is derived and analyzed. Then, to avoid the magnetic coupling between compensation windings and phase windings, a novel compensation module with independent magnet circuit is presented and attached to the primary side of FSPMLM. Thirdly, the two detent force reduction methods are compared with each other, and the compensation module is proved to be more effective. Finally, a prototype of FSPMLM with compensation modules is manufactured and tested to validate the proposed compensation method. Index Terms-Flux-switching linear permanent magnet motor (FSPMLM), detent force, compensation coil, compensation module. I. INTRODUCTIONINEAR MOTORS possess several advantages such as rapid dynamic response, high precision, excellent reliability and quiet operation. Therefore, this kind of motor is greatly required in the occasions where linear motion is needed, such as rail transit, ropeless elevator, and electromagnetic launch [1][2][3][4][5]. However, for the applications demanding extremely long secondary, such as rail transit and ropeless elevator, the conventional permanent magnet linear synchronous motor (PMLSM) is inappropriate, because large amount of expensive permanent magnets or copper windings are indispensable. Flux-switching linear permanent magnet motor (FSPMLM) is more appropriate for the long secondary occasions, because its permanent magnets and windings are all installed in the primary side. Its secondary side only consists Manuscript

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Since the fair value has been used, it has always been paid more attention to, after the financial crisis, it has caused widespread denunciation of the academic session. In the new accounting standards issued in 2014, the attention of fair value has always been very high, which can reflect the influence of enterprises on earnings management through the measurement of fair value. By describing the application of fair value under the new criteria to pave the way for the following description. The back illustrates the impact of fair value on earnings management under the new guidelines. At the end of the paper, some policies and constructive suggestions are put forward to improve earnings management in Chinese enterprises.

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