Question

A 25 Ω load is connected to the terminals of a 400 V terminal voltage parallel excited DC generator. The resistance of the field circuit is 200 Ω, the resistance of the armature is 0,4 Ω, the efficiency is 82%, the speed is 1000 r/min. Draw the equivalent circuit of the generator. Calculate the induced emf, the torque and the magnetic losses if the mechanical losses is 200 W.

Answer 1

252 Load, terminal voltage (4) - 4000 Resistance of field circuit IRA) = 2002 Resistance of armature circuit (Ra)= 0142 m%= 82% speed = 1ooorton -) () - 2010 - 20181000 104,72rague & Retour mechanical a losses (Pmech) = goone Equivalent A IF {Ra=0.42 1-400 L la le Eg 400 I = VE - 252 25 Ia = Izt IP = 16+2=18 Amp = 16 Amp is Its W7 - 400 goor 200 = 2 Amp Induced emf = Vt+ Tara 40 V7 18 %0.4 404. 2 volt Torque Egla 40 7.2 X 18 - tonime Now & output = VEIL m/= 0182= output som outpult Lossy - 900x 16 = 6400 wat Lossy = InRat I ² RF+ Pmecht Imagnetic Peore 6400 0.823 CHM + losses ) Losses =1404.84 watt

Lossy=1404 - 87 watt = 18 2x x 2 + 2 ФЕРТПат сhic 2) P magnetic = 245024 watt so magnetic losses = 257.24 watt