Chapter 11 : Neutral Grounding

Example 11.1, Page No 251

In [1]:
import math
#initialisation of variables
C1=2*math.pi*(10**-9)/(36*math.pi*math.log((4*4*8)**(1.0/3)/(10*(10**-3))))

#Calculations
C=C1*192*(10**9)     #capacitance per phase (micro farad)
L=(10)**6.0/(3*314*314*C)
V=132.0        #voltage (kV)
MVA=V*V/(3.0*314*L)

#Results
print("inductance ,L=%.2f H" %L)
print("MVA rating of suppressor  coil =%.3f MVA per coil" %MVA)

inductance ,L=1.97 H
MVA rating of suppressor  coil =9.379 MVA per coil

Example 11.2, Page No 252

In [2]:
import math
#initialisation of variables
wL=1.0/(3*314*(10)**-6)

#Calculations
print("(i)inductive reactance for 100 percent of the length of line=%.1f ohms" %wL)
wL=10.0**6/(3*314*.9)

#Results
print("(ii)inductive reactance for 90percent of the length of line=%.1f ohms" %wL)
wL=1.0/(3*314*(10)**-6)/.8
print("(iii)inductive reactance for 80 percent of the length of line=%.1f ohms" %wL)

(i)inductive reactance for 100 percent of the length of line=1061.6 ohms
(ii)inductive reactance for 90percent of the length of line=1179.5 ohms
(iii)inductive reactance for 80 percent of the length of line=1327.0 ohms