{
 "cells": [
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "# Chapter 16: Power in AC Circuits"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## Example 16.1, Page 329"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 6,
   "metadata": {
    "collapsed": false
   },
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "(a) Apparent power, S = 250 VA\n",
      "(b) Power Factor = 0.866\n",
      "(c) Active Power, P = 216.5\n"
     ]
    }
   ],
   "source": [
    "import math\n",
    "\n",
    "#Initialisation\n",
    "V=50                     #Voltage\n",
    "I=5                     #Current in Ampere r.m.s\n",
    "phase=30                 #in degrees\n",
    "\n",
    "#Calculation \n",
    "S=V*I                            #apparent power\n",
    "pf=math.cos(phase*math.pi/180)    #power factor\n",
    "apf=S*pf                          #active power\n",
    "\n",
    "#Result\n",
    "print'(a) Apparent power, S = %d VA'%S\n",
    "print'(b) Power Factor = %.3f'%pf\n",
    "print'(c) Active Power, P = %.1f'%apf"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## Example 16.2, Page 331"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 16,
   "metadata": {
    "collapsed": false
   },
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      " Apparent Power, P = 2000 W\n",
      " Active Power, P = 1500 W\n",
      " Reactive Power, Q = 1322 var\n",
      " Current I = 8.33 A\n"
     ]
    }
   ],
   "source": [
    "import math\n",
    "\n",
    "#Initialisation\n",
    "pf=0.75                          #power factor\n",
    "S=2000                           #apparent power in VA\n",
    "V=240                             #Voltage in volts\n",
    "\n",
    "#Calculation \n",
    "apf=S*pf                          #active power\n",
    "sin=math.sqrt(1-(pf**2)) \n",
    "Q=S*sin                           #Reactive Power\n",
    "I=S*V**-1                          #Current\n",
    "#Result\n",
    "print' Apparent Power, P = %d W'%S\n",
    "print' Active Power, P = %d W'%apf\n",
    "print' Reactive Power, Q = %d var'%Q\n",
    "print' Current I = %.2f A'%I"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## Example 16.3, Page 333"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 19,
   "metadata": {
    "collapsed": false
   },
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      " Apparent Power, S = 1500 W\n",
      " Active Power, P = 1500 W\n",
      " Reactive Power, Q = 1322 var\n",
      " Current I = 6.25 A\n"
     ]
    }
   ],
   "source": [
    "import math\n",
    "\n",
    "#Initialisation\n",
    "pf=0.75                          #power factor\n",
    "S=1500                           #apparent power in W\n",
    "V=240                             #Voltage in volts\n",
    "P1 = 2000                         #apparent power\n",
    "P2 = 1500                          #active power\n",
    "Q = 1322                           #reactive power\n",
    "I = 8.33                            #current in amp\n",
    "f=50                                #frequency in hertz\n",
    "\n",
    "#Calculation \n",
    "Xc=V**2/Q                        #reactive capacitance\n",
    "C=1/(Xc*2*math.pi*f)             #capacitance\n",
    "I=S*V**-1                             #current\n",
    "\n",
    "#Result\n",
    "print' Apparent Power, S = %d W'%S\n",
    "print' Active Power, P = %d W'%apf\n",
    "print' Reactive Power, Q = %d var'%Q\n",
    "print' Current I = %.2f A'%I"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## Example 16.4, Page 335"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 24,
   "metadata": {
    "collapsed": false
   },
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "Zl = (50+20j)\n"
     ]
    }
   ],
   "source": [
    "import math\n",
    "import numpy as np\n",
    "\n",
    "#Initialisation\n",
    "Zo=complex(50,-20)               #complex form of output impedance\n",
    "\n",
    "#Calculation \n",
    "Zl=np.conjugate(Zo)              #complex form of Load impedance\n",
    "\n",
    "#Result\n",
    "print'Zl = %s'%Zl"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {
    "collapsed": true
   },
   "outputs": [],
   "source": []
  }
 ],
 "metadata": {
  "kernelspec": {
   "display_name": "Python [Root]",
   "language": "python",
   "name": "Python [Root]"
  },
  "language_info": {
   "codemirror_mode": {
    "name": "ipython",
    "version": 2
   },
   "file_extension": ".py",
   "mimetype": "text/x-python",
   "name": "python",
   "nbconvert_exporter": "python",
   "pygments_lexer": "ipython2",
   "version": "2.7.12"
  }
 },
 "nbformat": 4,
 "nbformat_minor": 0
}