Question

State the relationship between total rotor power, mechanical power generated by the rotor of an relationship in terms of slip 's' rotor losses and the induction motor. Give this

Answer 1

Slip 's' = N_s - N_r/N_s Let's Look at table In induction motor as shown above, rotor power is the power obtained from stator ouput rightarrow because of losses, some power is lost which is copper loses and iron loss. rightarrow here rotor iron loss is less than cu losses because frequency f_r = sf f_r < < f, & sigma ddy current, hystressing loss depends on frequency, Then iron losses is neglected Then rotor losses = rotor capper losses \r\n rotor losses = rotor i/p - rotor o/p = 2 pi tau g/60(N_s - N_r) rightarrow rotor losses/ rotor i/p = 2 pi tau_g/60(N_s - N_r)/2 pi/60 tau_gN_s = N_s - N_r/N_s = s rightarrow rotor o/p/rotor i/p = 2 pi T_gN_r/co/2 pi T_gN_s/co = N_r/N_s = n_s(1 - s)/N_s = 1 - s rightarrow Then relation between them is rightarrow i/p: rotor losses: rotor o/p rightarrow 2 pi tau_gN_s/60: s times rotor i/p: (1 - s) rotor i/p 1