In [2]:

    

#importing all required modules
#important otherwise pop-up window may not work
%matplotlib inline 
import numpy as np
import scipy as sp
import matplotlib as mpl
import matplotlib.pyplot as plt
from math import *


    

In [3]:

    

# RMS value of voltage
u = 230 

#time vector
t = np.linspace(0,0.08, 100)

#frequency & angular frequency
f = 50
omega = 2 * pi * f

#closing angle [rad]
alpha = 0

#Resitance
R = 5

#Inductance
L = 0.1
XL = 2*pi*f*L

#Phase angle
phi=atan(XL/R)


    

In [4]:

    

print "Reactance value:", XL 
print "Phase angle value:", phi


    

    




Reactance value: 31.4159265359
Phase angle value: 1.41296513651

In [5]:

    

ua = [sqrt(2)*u*sin(omega*k + alpha) for k in t]
ub = [sqrt(2)*u*sin(omega*k + 2*pi/3 + alpha) for k in t]
uc = [sqrt(2)*u*sin(omega*k - 2*pi/3 +alpha) for k in t]


    

In [13]:

    

plt.plot(t,ua,t,ub,t,uc)
plt.title("Three phase voltages")
plt.xlabel("Time [s]")
plt.ylabel("Voltage [V]")
plt.axis([0, 0.02, -400, 400])
plt.grid(True)


    

In [10]:

    

#Phase A
#Current response
ia = [(sqrt(2)*u/(sqrt(R**2+XL**2))*(sin(omega*k+alpha-phi)-sin(alpha-phi)*exp(-R/L*k))) for k in t]

#DC component of the current
iadc = [(sqrt(2)*u/(sqrt(R**2+XL**2))*-sin(alpha-phi)*(exp(-R/L*k))) for k in t]

#AC steady state current
iau = [(sqrt(2)*u/(sqrt(R**2+XL**2))*sin(omega*k+alpha-phi)) for k in t]

#Phase B
#Current response
ib = [(sqrt(2)*u/(sqrt(R**2+XL**2))*(sin(omega*k+alpha-phi+4*pi/3)-sin(alpha-phi+4*pi/3)*exp(-R/L*k))) for k in t]

#DC component of the current
ibdc = [(sqrt(2)*u/(sqrt(R**2+XL**2))*-sin(alpha-phi+4*pi/3)*(exp(-R/L*k))) for k in t]

#AC steady state current
ibu = [(sqrt(2)*u/(sqrt(R**2+XL**2))*sin(omega*k+alpha-phi+4*pi/3)) for k in t]

#Phase C
#Current response
ic = [(sqrt(2)*u/(sqrt(R**2+XL**2))*(sin(omega*k+alpha-phi+2*pi/3)-sin(alpha-phi+2*pi/3)*exp(-R/L*k))) for k in t]

#DC component of the current
icdc = [(sqrt(2)*u/(sqrt(R**2+XL**2))*-sin(alpha-phi+2*pi/3)*(exp(-R/L*k))) for k in t]

#AC steady state current
icu = [(sqrt(2)*u/(sqrt(R**2+XL**2))*sin(omega*k+alpha-phi+2*pi/3)) for k in t]


    

In [23]:

    

plt.figure(1)
plt.subplot(111)
plt.plot(t,ia,t, iadc, t, iau)
plt.title("Currents in Phase A")
plt.xlabel("Time [s]")
plt.ylabel("Current [A]")
plt.grid(True)

plt.figure(2)
plt.subplot(111)
plt.plot(t,ib,t, ibdc, t, ibu)
plt.title("Currents in Phase B")
plt.xlabel("Time [s]")
plt.ylabel("Current [A]")
plt.grid(True)

plt.figure(3)
plt.subplot(111)
plt.plot(t,ic,t, icdc, t, icu)
plt.title("Currents in Phase C")
plt.xlabel("Time [s]")
plt.ylabel("Current [A]")
plt.grid(True)


    

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