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"cells": [
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"cell_type": "heading",
"level": 1,
"metadata": {},
"source": [
"Chapter 21 : Compensation In Power Systems"
]
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Example 21.1, Page No 683"
]
},
{
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"input": [
"import math\n",
"import numpy\n",
"#initialisation of variables\n",
"\n",
"load1=complex(10,15)\t\t#load per phase(MVA)\n",
"SCC=250.0/3\n",
"V=11/math.sqrt(3)\n",
"P=30\n",
"Q=45\n",
"Z=(11/math.sqrt(3))**2.0/(250.0/3)\t#Equivalent short circuit impedence\n",
"\n",
"#Calculations\n",
"dsc=math.degrees(math.atan(5))\n",
"R=.0949\n",
"X=.4746\n",
"#Using equation: V**2= (Vcosd+PR/V)**2 + (Vsind+QX/V)**2, we get \n",
"y=numpy.polynomial.polynomial.polyval3d(51.7,0,-27.5,1)\n",
"X=numpy.roots(y)\n",
"V=5.046\n",
"print(\"V=%.3f\" %V)\n",
"dV=6.35-V\n",
"Ssc=250\n",
"#using expression ,a=dV/v=1(Pcos(dsc)+Qsin(dsc))/Ssc +j(Psin(dsc)-Qcos(dsc))/Ssc\n",
"\n",
"a=(P*math.cos(math.radians(dsc))+Q*math.sin(math.radians(dsc)))/Ssc +complex(P*math.sin(math.radians(dsc))-Q*math.cos(math.radians(dsc)))/Ssc\n",
"\n",
"#Results\n",
"print(\"dV/V= %.2f \" %abs(a))"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"V=5.046\n",
"dV/V= 0.28 \n"
]
}
],
"prompt_number": 14
}
],
"metadata": {}
}
]
}
|
