The iron core is used to maximize the coupling between the coils (formed by conductors) placed on the stator and rotor, to increase the flux density in the machine and to decrease the size of machine.

铁芯用于使放置在转子和定子中的线圈（由导体构成）之间的耦合最大，以增加电机的磁通密度以及减小电机尺寸。

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