INDUCTION MOTOR 349 



The following equations show the relations between the various 

 e.m.f.'s and currents at slip s. 

 Rotor current 



= E' (a,- ja 2 ). (319) 



Stator load current 



!' =h = E'(a 1 -jaz) ...... (320) 



Stator exciting current 



I. = E'y = E'(g-jb) ...... (321) 



Total stator current 



/! = l f + I e = E f } (ai + g) - j (a 2 + 6) } = E' (b, - J6 2 ). (322) 



E.m.f. impressed on the stator 



! = E' + J 1?1 = E' + E' (6i - J6 2 ) ( 

 = E' I (1 + 6^1 + tei) + j (61X1 - 6 2 rO J 



.......... (323) 



its absolute value which remains constant is 



E l = E' V Cl 2 + c 2 2 . (324) 



Thus the e.m.f. generated in the stator is 



E' = 2 El = . ...... (325) 



Substituting this value for E' in the equations above the abso- 

 lute values of the various quantities at slip s can be obtained. 



Rotor current 



J 2 = I f = E' Vai 2 + a 2 2 = E l ^ + ' Q ~. . . (326) 



Exciting current 



I e = E' Vg 2 -f- b 2 = EI JLJ (327) 



Stator current 



T rj/ ^ /r~9 i r~9" TJ v 61 



2 -4- /i 2 



"... . . (328) 



V + c, 2 



