Question

NIE 2294 exam 2019.20 Aman Attya NIE 220 m Altya Question 3 NE A 100 MVA, 12.5 kV, 50-Hz, two-pole, Y-connected synchronous generator has a per-unit synchronous reactance of 1.1 and a per-unit armature resistance NIE 2296 Gram 2010-20 Ayman Allys of 0.012. The machine baseline voltage is 12.5 kV. y Altya NIE 294 2019-20 yman AltyaNEm 2012 An Atty (a) Calculate the synchronous reactance and armature resistance in ohms and sketch the NIE equivalent circuit NIE 2017 many (5 marks) If the machine is delivering its rated power at 0.85 lagging power factor, calculate: 20 Ayman Altya (b) The internal voltage NIEWYSam 2019 20 yen Atty NIE cam 2015 (8 marks) NIE22 am2010- NE2220 Aman Ally NE(C) The power angle. NIE 20 NE2204, 2010 2011 (2 marks) NIE (d) The applied prime mover torque. cxam 2010-20 Ayu Arya (5 marks) NE220 cm 2012 An Atly (e) Calculate the voltage regulation of this machine. Altya NIE2290 Alya NIE 2010-20A(5 marks) NIE 224 am 2019-20 Ayman Ally NIE229 2010-20Aman Ally NIE2290 ram 2010-20 Ayar Altya NESA 2020 [25 marks) NIE220 Exam 2018-20 Ayan Ally NIE 22 An Ally NIE 220 cm 2013-20 Aman Ally NIEC2 2012 An Ally NIE2290 cam 2018-20 Aman Altya NE229 2012 An Allya NIE 2010 All NIE 2010 NIE 2012 NIE.com 2012 Ayman Atty NIEZ2 2010 Ally NIE229 20120 A A NIE

Answer 1

Terminal Given that, Thermal voltage 4 = 12 ob k V Powere Factor, PF = 0.85 lagging Freequency fe = 50 Hz Syncheondus seactånce o X opu hol per unit Armature Resistanco. =Rph 0.012 per unit Spase s TOOMVA Synchronous reactance and armatwie resistance i The base phase voltage of this generaton is Vo, base = Vr = 12.6k = 7217 V 3 J3 la The base impedance of the generator is 3 Ver base 30721772 1056 2 100 M S 2 base - base generator The impedance in otions are Ra Rpu XZ base = 0.012) (156) = 0.01872 Xs= Xeux Zbase = (1.1) (-1.56 ) = 5o 7.16 R. A jxs RA=0.0187 N plotis IK LE =72170 Figure - Perphase equivalent cricult

(6) Internal voltage en The interenal voltage EA EA: Vo thATA tj X, IA Vo=721720° (calculated above) RA=0.01872 Scalculated above) xs = 1.796R (calculated above) IA can be calculated as below: IA = I=s Joom = 46 19 A FK 3x (125k) G= -cos IPF -cost (0.85) =-31.790 2. IA 46392-31.29°A Now, A. Vo trattatjX; TA En = 7217 20°+ (0.0192) 46194-31290) ; (1.74646191-3179 En = 13275 230° 3° v (C) Power angle a Forom above, Magnitude of internal voltage EA = 1275V and angle is de 3 B. Pewexe angle $330.3°

The applied prime mover torque: Ignoscung losses, the input po were would be equal to the output power Pin = Pout - PF XS =(0.85) (100 M) 2 Tapp = Pin and 120fc 120 (50) = 3000 elmina P 8. Applied prime mover torque, 85 M (3000 / min) (2 Teadle) (I min / 60s) ?app 270563 Nom Voltage regulation VR = EA - Vo, base 100% [Magnitude of Ex Varanasi Ves 13275-7217 x 100% 7217 VR= 83.gut le