VOLTAGE RATIO IN SYNCHRONOUS CONVERTERS 227 

 and that for the fundamental 



sin 



P' 



2Nsp X 



sin 



(5) 



The ratio kdm+kai is the relative reduction of the wth harmonic 

 by belt-differential action; it may conveniently be called the belt- 

 reduction factor, and is 



sn 



2Ns 



sin sm 

 P 



(6) 



sin 



The first part of km, namely, 





, is independent of Nsp and is 



equal to i, except for m=T >) 9 or 15, when it is zero for p'=$, 

 2 for p' = 6. 



The following table gives the value of the second part of 

 which is equal to k m except for the cases above cited. 



TABLE II 



TABLE OF sin -J-sin-^ 



2Nsp 2Nsp 



As krm is in most cases much less than one, it appears that the 

 harmonics are much more reduced by the belt-differential action than 

 is the fundamental. 



