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## Example16_9_pg617.sce
## Effect of phase control
## Theory of Alternating Current Machinery by Alexander Langsdorf
## First Edition 1999, Thirty Second reprint
## Tata McGraw Hill Publishing Company
## Example in Page 617
import math
## Given data
phi = 20.;
alpha1 = 30.;
alpha2 = 0.;
## Calculations
ans1 = (math.cos(phi*math.pi/(180.*2.))*math.cos(phi*math.pi/(180.*2.) + alpha1*math.pi/180.)*100.);
ans2 = round(math.cos(phi*math.pi/(180.*2.))*math.cos(phi*math.pi/(180.*2.) + alpha2*math.pi/180.)*100.);
Effect = (ans1/ans2)*100.;
print'%s %.2f %s'%("\n\nEffect of phase control here is to reduce the dc voltage to ",Effect," of the value it would have in the absence of phase control\n");
## Result
## Effect of phase control here is to reduce the dc voltage to 77.77 % of the value it would have in the absence of phase control
```