CHAPTER II 

 DETAILED STUDY OF OPERATION WITH NORMAL LOAD 



I. PRINCIPLES OF THE ELEMENTARY THEORY 



Notation. Let 



R = the resistance of the total circuit of the motor (including the motor, 

 the line, and the armature of the generator, in the case of an 

 electric transmission system. (The armature resistance of the 

 alternators is supposed to be increased from 50 to 100 per cent 

 in such a way as to take into consideration the eddy currents 

 produced by the armature in the pole-pieces); 



L=the mean inductance of the motor; 

 /=that of the external circuit (including line and generator); 



27T 



r=the period; o> = =the velocity of pulsation; 



X=the reactance of the total circuit, including the motor; X =uj(L+l); 

 Z=the impedance of the total circuit, including the motor: 



E\=^ the effective external E.M.F., i.e., the E.M.F. obtained from the 

 line (or induced in the generator, in the case of an ordinary 

 simple transmission system). This E.M.F. is supposed constant, 

 unless otherwise stated, in all that follows; 



2=the effective internal E.M.F. induced in the synchronous motor, 

 such as it would be measured on open circuit with the same 

 excitation. (E 2 should not be confounded with the resultant 

 induced or effective E.M.F. produced by the resultant field of 

 the field ampere-turns and of the armature-reaction. The 

 latter will be designated, later, by the symbol 2-) 

 e = the resultant E.M.F. of the two E.M.F's. EI and E 2 ; 

 7=the current in the armature of the motor; 

 Pi=the electric power produced by the E.M.F. E\; 



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