MGVCL Exam Paper (30-07-2021 Shift 1)
The necessary equation to be solved during the load flow analysis using Fast-Decoupled methid is given below: where B' and B'' are formed using the imaginary part of the bus admittance matrix Ybus, n is the total number of buses in the system, m is the number of voltage regulated buses. The size of matrix B' is ∆P/|Vi|= -B' ∆δ ∆Q/|Vi| = -B'' ∆|Vi|
In FDLF method, B' corresponds to susceptance of unknown of PQ and PV bus Order of B' matrix is = (n -1)*(n - 1) Where n is total no. of buses. Order of B'' = (n - m - 1)*(n - m - 1)
The ratio of full load current to short circuit current = 1/5 Xsc = j/(1/5) External reactance required = j*((1/5) - 0.05)) = j*0.15 pu Full load current = (30*1000)/(√3*11) = 1574.6 A Per unit reactance = j*0.15 = (I*Xr)/V j*0.15 = (1574.6*Xb)/((11/√3)*1000)) = 0.60 ohm
Tank - Name of power station - capacity 1 - Vindhyachal Thermal Power Station - 4,760MW. 2 - Mundra Thermal Power Station - 4620 MW 3 - The Sasan Ultra Mega power plant - 3960 MW 4 - The Tiroda thermal power plant - 3300 MW
Let, E→EMF in volt φ→Flux in weber A→Parallel path (for wave winding = 2) Z→No. of armature conductors N→speed in rpm P = Number of poles E = PφNZ/(60A) E = 8*0.020*625/(60*2) E = 500 V
EXAMIANS