Home For the forces analysis let us consider the case when electric roller contacts by its pole with some point of the stator where the stator pole is located. In general the contact point is not the stator pole. Let us call this point the beginning point on the stator. Let us denote the distance between the beginning point and the nearest stator pole, measures along the stator arch as Ubeg . ===> This picture ===> hows the graphs of horizontal forces Fbeg of the magnets attraction Ubeg . In the first five windows the graphs of these forces are shown for Ubeg={0.01,0.005,0,0.005,0.01}. One can see that the force changes its sign, but the integral along the stator surface as a rule is not equal to zero. The exception is in the case when Ubeg=0. But this integral is equal to the work A(Ubeg) of the force Fbeg(U). This force is directed around the stator, and, due to the above said, performs work when the roller moves (as a rule). In the sixth window a graph is built of the dependence of work A(Ubeg) on Ubeg. Apparently, this work mat have any sign. Let us consider also the work Ar(Ubeg), performed by the attractive forces of all poles of one roller to the given stator pole and also the work As(Ubeg), performed by the attractive forces of all poles of one roller to all stator poles. ===>

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