# Variables
P = 4; #no. of poles
c = 2; #no. of parallel paths
p = 4./2; #no. of pair of poles
S = 51; #no. of slots
C = 12; #conductors per slot
N = 900; #rpm(speed)
fi = 25./1000; #Wb
# Calculations
Z = S*C; #total no. of conductors
E = 2*Z/c*N*p/60*fi; #V
# Results
print "Generated emf(V): %.2f"%E
# Variables
P = 8.; #no. of poles
c = 8.; #no. of parallel paths
p = 8./2; #no. of pair of poles
E = 260.; #V(generated emf)
fi = 0.05; #Wb
S = 120; #no. of slots
N = 350; #rpm(speed)
# Calculations
Z = E/(2./c*N*p/60*fi); #V
# Results
print "No. of conductors per slot",int(Z)
# Variables
Ra = 0.1; #ohm(Armature Resistance)
Vs = 250; #V(supply voltage)
# Calculations and Results
#part(a)
I = 80; #A
Vdrop = Ra*I; #V
emf = Vs+Vdrop; #V(Generated emf)
print "Part(a) Generated emf(V) : %.2f"%emf
#part(b)
I = 60; #A(current taken by Motor)
Vdrop = Ra*I; #V
emf = Vs-Vdrop; #V(Generated emf)
print "Part(b) Generated emf(V) : %.2f"%emf
# Variables
P = 4; #no. of poles
Vs = 440; #V
c = 2; #no. of parallel paths
p = 4./2; #no. of pair of poles
Ia = 50; #A
Ra = 0.28; #ohm
Z = 888; #conductors
fi = 0.023; #Wb
# Calculations
emf = Vs-Ia*Ra; #V
N = emf/(2*Z/c*p/60*fi); #rpm
# Results
print "Speed in rpm",round(N)
import math
# Variables
N = 900; #rpm
Vs = 460.; #V
Vs_new = 200; #V
fi_ratio = 0.7; #ratio of new flux to original flux
# Calculations
kfi = Vs/N; #for original flux
Nnew = Vs_new/kfi/fi_ratio; #rpm(new speed)
# Results
print "Speed in rpm",round(Nnew)
import math
# Variables
Ia = 110; #A
Vs = 480; #V
Ra = 0.2; #ohm
P = 6.; #no. of poles
c = 6.; #no. of parallel paths
p = P/2; #no. of pair of poles
Z = 864; #no. of conductors
fi = 0.05; #Wb
# Calculations and Results
emf = Vs-Ia*Ra; #V
N = emf/(2*Z/c*p/60*fi); #rpm
print "(a) Speed in rpm",round(N)
Pm = Ia*emf; #W(Mechanical power developed)
M = Pm/(N/60)/(2*math.pi); #Nm(Torque)
print "(b) Gross torque developed(Nm) : %.f"%M
import math
# Variables
N = 15; #rps
M = 2*1000; #Nm(Torque required)
Loss = 8*1000; #W
# Calculations
P = 2*math.pi*M*N; #W(Power required)
Pa = P-Loss; #W(Power generated in armature)
# Results
print "Power generated in armature(kW) : %.2f"%(Pa/1000)