In [1]:

```
#Variable declaration
#Given Torque-Speed relations shown in Fig.11-3b page no-371 for a dc servomotor
#Calculation
#Case(a)
S = 800.0 #Motor speed at point x(rpm). Extrapolating to load line point x
V = 60.0 #Armature voltage at point x(V)
#Case(b)
T = 4.5 #At standstill, 60 V yields 4.5 lb-ft of starting torque
#Case(c)
P_c = T*S/5252 #Power delivered to the load(hp). From case(a)
P_c_watt = P_c*746 #Power delivered to the load(W)
#Case(d)
T_d = 1.1 #Torque for continuous duty without cooling fan(lb-ft). At point o
S_d = 410.0 #Maximum load speed(rpm)
#Case(e)
T_e = 2.4 #Torque for continuous duty with cooling fan(lb-ft). At point w
S_e = 900.0 #Maximum load speed(rpm)
#Case(f)
P_d = T_d*S_d/5252 #Power delivered to the load(hp). From case(d)
P_d_watt = P_d*746 #Power delivered to the load(W)
#Case(g)
P_e = T_e*S_e/5252 #Power delivered to the load(hp). From case(e)
P_e_watt = P_e*746 #Power delivered to the load(W)
#Case(h)
A = 65.0 #Upper limit of power range A(W)
B = 305.0 #Upper limit of power range B(W)
#Result
print('Case(a): Motor speed when load torque is 2.1 lb-ft at point x , S = %.f rpm' %S)
print(' Armature voltage when load torque is 2.1 lb-ft at point x , V = %.f V' %V)
print('Case(b): Motor starting torque using the voltage found in part(a) , T_st = %.1f lb-ft' %T)
print('Case(c): Power delivered to the load under conditions given in part(a) , P = %.3f hp = %.f W' %(P_c,P_c_watt))
print('Case(d): Maximum load speed for continuous duty without cooling fan , S = %.f rpm' %S_d)
print(' Torque for continuous duty without cooling fan , T = %.1f lb-ft' %T_d)
print('Case(e): Maximum load speed for continuous duty with cooling fan , S = %.f rpm' %S_e)
print(' Torque for continuous duty with cooling fan , T = %.1f lb-ft' %T_e)
print('Case(f): Power delivered to load in part(d) , P = %.4f hp = %.1f W' %(P_d,P_d_watt))
print('Case(g): Power delivered to load in part(e) , P = %.3f hp = %.f W' %(P_e,P_e_watt))
print('Case(h): Upper limit of power range , A = %.f W' %A)
print(' Upper limit of power range , B = %.f W' %B)
```

In [1]:

```
#Variable declaration
n = 3.0 #Number of stacks or phases
P_a = 16.0 #Number of rotor teeth
P_b = 24.0 #Number of rotor poles
#Calculation
alpha_a = 360/(n*P_a) #Stepping angle(degree/step)
alpha_b = 360/(n*P_b) #Stepping angle(degree/step)
#Result
print('Case(a): Stepping angle , α = %.1f°/step' %alpha_a)
print('Case(b): Stepping angle , α = %.1f°/step' %alpha_b)
```

In [1]:

```
#Variable declaration
P = 50.0 #Number of rotor teeth
#Calculation
alpha = 90/P #Stepping length(degrees)
#Result
print('α = %.1f° ' %alpha)
```

In [1]:

```
#Variable declaration
tou = 0.1 #Pole pitch of a double-sided primary LIM(m)
f = 60.0 #Frequency applied to the primary LIM(Hz)
#Calculation
v_s = 2*f*tou #Synchronous velocity(m/s)
#Result
print('Synchronous velocity , v_s = %.f m/s' %v_s)
```

In [1]:

```
#Variable declaration
v_s = 12.0 #Synchronous velocity(m/s)
v = 10.0 #Linear velocity of secondary sheet(m/s)
#Calculation
s = (v_s-v)/v_s #Slip of the DSLIM
#Result
print('Slip of the DSLIM , s = %.3f' %s)
```