{ "cells": [ { "cell_type": "markdown", "metadata": {}, "source": [ "# Chapter 7: Speciality Machines" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "## Example 7.1: Determine_Torque_load_on_the_shaft_and_Torque_angle_if_the_voltage_drops_to_224V.sce" ] }, { "cell_type": "code", "execution_count": null, "metadata": { "collapsed": true }, "outputs": [], "source": [ "// Example 7.1\n", "// Determine (a) Torque load on the shaft (b) Torque angle if the voltage \n", "// drops to 224V (c) Will the rotor pull out of synchronism?\n", "// Page No. 282\n", "\n", "clc;\n", "clear;\n", "close;\n", "\n", "// Given data\n", "f=60; // Frequency\n", "P=4; // Number of poles\n", "Pshaft=10; // Shaft power in hp\n", "V1=240; // Rated voltage\n", "V2=224; // New voltage\n", "phirel1=30; // Torque angle\n", "\n", "\n", "// (a) Torque load on the shaft\n", "ns=120*f/P; // speed of machine\n", "Trel=Pshaft*5252/ns;\n", "\n", "\n", "// (b) Torque angle if the voltage drops to 224V\n", "phirel2=asind((V1^2/V2^2)*sind(2*phirel1))/2\n", "\n", "// Display result on command window\n", "printf('\n Torque load on the shaft = %0.2f lb-ft ',Trel);\n", "printf('\n Torque angle if the voltage drops to 224V = %0.2f deg ',phirel2);\n", "printf('\n Because torque angle is less than 45 degree, \n the rotor will not pull out of synchronism ')\n", "" ] } , { "cell_type": "markdown", "metadata": {}, "source": [ "## Example 7.2: Determine_Resolution_and_Number_of_steps_required_for_the_rotor_and_Shaft_speed.sce" ] }, { "cell_type": "code", "execution_count": null, "metadata": { "collapsed": true }, "outputs": [], "source": [ "// Example 7.2\n", "// Determine (a) Resolution (b) Number of steps required for the rotor to make \n", "// 20.6 revolutions (c) Shaft speed if the stepping frequency is 1800 pulses/s\n", "// Page No. 287\n", "\n", "clc;\n", "clear;\n", "close;\n", "\n", "// Given data\n", "betaa=2; // Step angle\n", "theta=20.6; // Number of revolutions\n", "fp=1800; // Stepping frequency\n", "\n", "\n", "// (a) Resolution\n", "stepsperrev=360/betaa; // Speed of machine\n", "\n", "\n", "// (b) Number of steps required for the rotor to make 20.6 revolutions\n", "steps=theta*360/betaa;\n", "\n", "\n", "// (c) Shaft speed if the stepping frequency is 1800 pulses/s.\n", "n=betaa*fp/360;\n", "\n", "\n", "// Display result on command window\n", "printf('\n Resolution = %0.0f ',stepsperrev);\n", "printf('\n Number of steps required for the rotor to make 20.6 revolutions = %0.0f ',steps);\n", "printf('\n Shaft speed if the stepping frequency is 1800 pulses/s = %0.0f r/s ',n);\n", "" ] } , { "cell_type": "markdown", "metadata": {}, "source": [ "## Example 7.3: Determine_Synchronous_speed_and_Rail_speed.sce" ] }, { "cell_type": "code", "execution_count": null, "metadata": { "collapsed": true }, "outputs": [], "source": [ "// Example 7.3\n", "// Determine (a) Synchronous speed (b) Rail speed assuming slip of 16.7%\n", "// Page No. 299\n", "\n", "clc;\n", "clear;\n", "close;\n", "\n", "// Given data\n", "f=50; // Frequency of machine\n", "tau=0.24; // Pole pitch\n", "s=0.167; // Slip\n", "\n", "// (a) The synchronous speed \n", "Us=2*tau*f;\n", "\n", "// (b) Rail speed assuming slip of 16.7 percent\n", "U=Us*(1-s);\n", "\n", "\n", "// Display result on command window\n", "printf('\n The synchronous speed = %0.0f m/s ',Us);\n", "printf('\n Rail speed assuming slip of 16.7 percent = %0.1f m/s ',U);\n", "" ] } ], "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 }