I2′=(Rs+SRr)+j(Xis+Xir)vpn=(0.15+0.040.12)+j(0.45+0.45)230.94∠0=70.494∠−15.950
Im=jXmVpm=j28.5230.94∠0A=8.103∠−900
a. State current, Is=Im+Is′=73.137∠−22.060
b. Synchronuos speed Ns=P120f=4120∗50=1500rpm
Nr=Ns(1−s)=1500(1−0.04)=1440rpm
c. Air gap power, =3I2′2∗sRr⟹Pg=3(70.414)2∗(0.040.12)=44.7246kW
Rotor power developed =(1-s)Pg =(1-0.04)(44.7246)kW=42.936 kW
Rotational loss =400 W = 0.4 kW
Shaft power = 42.936 -0.4 =42.536 kW
Output torque, Tsh=2πNs60∗Shaftpoweroutput=2π∗144060∗42.536∗1000=282.07Nm
d. Total power output = 42.536 kW
Total power input = 3vpmIscosϕs=3(230.94)(73.137)cos22.06W=46.961kW
Efficiency=46.96142.536∗100=90.577%
Comments
Leave a comment