{ "cells": [ { "cell_type": "markdown", "metadata": {}, "source": [ "# Chapter 9: INSULATED CABLES" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "## Example 9.1: To_determine_the_economic_overall_diameter_of_a_1core_cable_metal_sheathead.sce" ] }, { "cell_type": "code", "execution_count": null, "metadata": { "collapsed": true }, "outputs": [], "source": [ "// To determine the economic overall diameter of a 1- core cable metal sheathead.\n", "clear\n", "clc;\n", "V=85;// working voltage (kV)\n", "gmax=65;// dielectric strength of insulating material (kV/cm)\n", "r=V/gmax;\n", "d=2*r;\n", "D=2.6*%e;\n", "mprintf('Diameter of the sheath =%.2f cm\n',D);" ] } , { "cell_type": "markdown", "metadata": {}, "source": [ "## Example 9.2: To_determine_the_minimum_internal_diameter_of_the_lead_sheath.sce" ] }, { "cell_type": "code", "execution_count": null, "metadata": { "collapsed": true }, "outputs": [], "source": [ "// To determine the minimum internal diameter of the lead sheath\n", "clear\n", "clc;\n", "e1=4;\n", "e2=4;\n", "e3=2.5;\n", "g1max=50;\n", "g2max=40;\n", "g3max=30;\n", "r=.5;// radius (cm)\n", "r1=r*e1*g1max/(e2*g2max);\n", "r2=r1*e2*g2max/(e3*g3max);\n", "V=66;\n", "lnc=(V-((r*g1max*log(r1/r))+(r1*g2max*log(r2/r1))));\n", "m=lnc/(r2*g3max);\n", "R=r2*(%e^m);\n", "D=2*R;\n", "mprintf('minimum internal diameter of the lead sheath,D=%.2f cms\n',D);" ] } , { "cell_type": "markdown", "metadata": {}, "source": [ "## Example 9.3: To_determine_the_maximum_safe_working_voltage.sce" ] }, { "cell_type": "code", "execution_count": null, "metadata": { "collapsed": true }, "outputs": [], "source": [ "// To determine the maximum safe working voltage\n", "clear\n", "clc;\n", "r=.5;//radius of conductor(cm)\n", "g1max=34;\n", "er=5;\n", "r1=1;\n", "R=7/2;//external dia(cm)\n", "g2max=(r*g1max)/(er*r1);\n", "V=((r*g1max*log(r1/r))+(r1*g2max*log(R/r1)));\n", "V=V/(sqrt(2));\n", "mprintf('Maximum safe working volltage ,V =%.2f kV r.m.s\n',V);" ] } , { "cell_type": "markdown", "metadata": {}, "source": [ "## Example 9.4: To_determine_the_maximum_stresses_in_each_of_the_three_layers.sce" ] }, { "cell_type": "code", "execution_count": null, "metadata": { "collapsed": true }, "outputs": [], "source": [ "//To determine the maximum stresses in each of the three layers .\n", "clear\n", "clc;\n", "r=.9;\n", "r1=1.25\n", "r2=r1+.35;\n", "r3=r2+.35;// radius of outermost layer\n", "Vd=20;// voltage difference (kV)\n", "g1max=Vd/(r*log(r1/r));\n", "g2max=Vd/(r1*log(r2/r1));\n", "g3max=(66-40)/(r2*log(r3/r2));\n", "mprintf('g1max =%.1f kV/cm\n',g1max);\n", "mprintf('g2max =%.2f kV/cm\n',g2max);\n", "mprintf('g3max =%.0f kV/cm\n',g3max);" ] } , { "cell_type": "markdown", "metadata": {}, "source": [ "## Example 9.5: o_dtermine_the_equivalent_star_connected_capacity_and_the_kVA_required.sce" ] }, { "cell_type": "code", "execution_count": null, "metadata": { "collapsed": true }, "outputs": [], "source": [ "//To dtermine the equivalent star connected capacity and the kVA required.\n", "clear\n", "clc;\n", "V=20;//voltage (kV)\n", "w=314;\n", "C=2*3.04*10^-6;//capacitance per phase(micro-farad)\n", "KVA=V*V*w*C*1000;\n", "mprintf('3-phase kVA required =%.0f kVA',KVA); //Answer don't match due to difference in rounding off of digits" ] } , { "cell_type": "markdown", "metadata": {}, "source": [ "## Example 9.6: EX9_6.sce" ] }, { "cell_type": "code", "execution_count": null, "metadata": { "collapsed": true }, "outputs": [], "source": [ "// Determine the capacitance (a)between any two conductors (b)between any two bunched conductors and the third conductor (c)Also calculate the charging current per phase per km\n", "clear\n", "clc;\n", "C1=.208;\n", "C2=.096;\n", "Cx=3*C1;\n", "w=314;\n", "V=10;\n", "Cy=(C1+ 2*C2);\n", "Co=((1.5*Cy)-(Cx/6));\n", "C=Co/2;\n", "mprintf('(i)Capacitance between any two conductors=%.3f micro-Farad/km\n',C);\n", "c=((2*C2 + ((2/3)*C1)));\n", "mprintf('(ii)Capacitance between any two bunched conductors and the third conductor=%.2f micro-Farad/km\n',c);\n", "I=V*w*Co*1000*(10^-6)/sqrt(3);\n", "mprintf('(iii)the charging current per phase per km =%.3f A\n',I);" ] } , { "cell_type": "markdown", "metadata": {}, "source": [ "## Example 9.7: To_calculate_the_induced_emf_in_each_sheath.sce" ] }, { "cell_type": "code", "execution_count": null, "metadata": { "collapsed": true }, "outputs": [], "source": [ "// To calculate the induced emf in each sheath .\n", "clear\n", "clc;\n", "rm=(2.28/2)-(.152/2);// mean radius of sheath (cm)\n", "d=5.08;\n", "a=d/rm;\n", "w=314;\n", "Xm=2*(10^-7)*log(a);// mutual inductance (H/m)\n", "Xm2=2000*Xm;\n", "V=w*Xm2*400;\n", "mprintf('Voltage induced =%.2f volts \n',V);//Answer don't match exactly due to difference in rounding off of digits i between calculations" ] } , { "cell_type": "markdown", "metadata": {}, "source": [ "## Example 9.8: To_determine_the_ratio_of_sheath_loss_to_core_loss_of_the_cable.sce" ] }, { "cell_type": "code", "execution_count": null, "metadata": { "collapsed": true }, "outputs": [], "source": [ "//To determine the ratio of sheath loss to core loss of the cable\n", "clear\n", "clc;\n", "R=2*.1625;\n", "Rs=2*2.14;\n", "M=314;\n", "w=6.268*10^-4;\n", "r=Rs*M*M*w*w/(R*((Rs^2)+(M*M*w*w)));\n", "mprintf('ratio=%.4f \n',r);" ] } ], "metadata": { "kernelspec": { "display_name": "Scilab", "language": "scilab", "name": "scilab" }, "language_info": { "file_extension": ".sce", "help_links": [ { "text": "MetaKernel Magics", "url": "https://github.com/calysto/metakernel/blob/master/metakernel/magics/README.md" } ], "mimetype": "text/x-octave", "name": "scilab", "version": "0.7.1" } }, "nbformat": 4, "nbformat_minor": 0 }