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diff --git a/backup/Fundamentals_of_Electrical_Drives_version_backup/Chapter10.ipynb b/backup/Fundamentals_of_Electrical_Drives_version_backup/Chapter10.ipynb new file mode 100755 index 00000000..5857660c --- /dev/null +++ b/backup/Fundamentals_of_Electrical_Drives_version_backup/Chapter10.ipynb @@ -0,0 +1,472 @@ +{ + "metadata": { + "name": "" + }, + "nbformat": 3, + "nbformat_minor": 0, + "worksheets": [ + { + "cells": [ + { + "cell_type": "heading", + "level": 1, + "metadata": {}, + "source": [ + "Chapter 10:Traction Drives" + ] + }, + { + "cell_type": "heading", + "level": 2, + "metadata": {}, + "source": [ + "Example No:10.1,Page No:320" + ] + }, + { + "cell_type": "code", + "collapsed": false, + "input": [ + "import math\n", + "from __future__ import division\n", + "\n", + "#variable declaration\n", + "Ma=480 #mass of each motor armature in kg 0.48tonne=480kg\n", + "Da=0.5 #average diameter of each motor in m\n", + "m=450 #mass of each wheel in kg\n", + "R=0.54 #radius of each wheel tread in m\n", + "M=40 #combine wight of one motor and one trailer coach in ton\n", + "alpha=5 #accelaration\n", + "N=4 #number of DC motors \n", + "a=0.4 #gear ratio\n", + "r=20 #train resistance\n", + "\n", + "#calculation\n", + "Jw=1/2*m*R**2 #inertia of the each wheel\n", + "nw=2*(N*2) #total number of wheels\n", + "J1=nw*Jw #total inertia of all the wheels\n", + "\n", + "Jm=N*(1/2*Ma*(Da/2)**2) #approximate inertia of all the motors\n", + "J2=Jm/a**2 #approximate innertia of the motor referred to the wheels\n", + "\n", + "Fa2=(J1+J2)*alpha*1000/3600/R #Tractive efforts for driving rorating parts\n", + "Fa1=277.8*M*alpha #tractive efforts to accelerate the train mass horizontally\n", + "Fr=r*M #Tractive efforts required to overcome train resistance\n", + "Ft=Fa1+Fa2+Fr #Tractive efforts required to move the train\n", + "Tm=a*R*Ft/N #torque per motor\n", + "\n", + "#results\n", + "print\"\\nTorque per motor:Tm=\",round(Tm,1),\"N-m\"" + ], + "language": "python", + "metadata": {}, + "outputs": [ + { + "output_type": "stream", + "stream": "stdout", + "text": [ + "\n", + "Torque per motor:Tm= 3241.3 N-m\n" + ] + } + ], + "prompt_number": 5 + }, + { + "cell_type": "heading", + "level": 2, + "metadata": {}, + "source": [ + "Example No:10.2,Page No:321" + ] + }, + { + "cell_type": "code", + "collapsed": false, + "input": [ + "import math\n", + "from __future__ import division\n", + "\n", + "#variable declaration\n", + "M=100 #mass of each motor armature in tonne\n", + "Me=100\n", + "Tm=5000 #torque of each motor in N-m\n", + "Da=0.5 #average diameter of each motor in m\n", + "m=450 #mass of each wheel in kg\n", + "R=0.54 #radius of each wheel tread in m\n", + "N=4 #number of DC motors \n", + "r=25 #train resistance N/tonne\n", + "a=0.25 #gear ratio \n", + "nt=0.98 #gear transmission efficiency\n", + "G=50 #up gradient\n", + "Vm=100 #speed in kmph\n", + "\n", + "#calculation \n", + "Ft=nt*Tm*N/a/R #Tractive efforts required to move the train\n", + "alpha=(Ft-(9.81*M*G+M*r))/(277.8*1.1*Me) #accelaration\n", + "t=Vm/alpha #time taken to attain speed of Vm\n", + "\n", + "#results\n", + "print\"\\n time taken to reach a speed of 100kmph is :t=\",round(t,1),\"sec\"" + ], + "language": "python", + "metadata": {}, + "outputs": [ + { + "output_type": "stream", + "stream": "stdout", + "text": [ + "\n", + " time taken to reach a speed of 100kmph is :t= 32.6 sec\n" + ] + } + ], + "prompt_number": 6 + }, + { + "cell_type": "heading", + "level": 2, + "metadata": {}, + "source": [ + "Example No:10.3,Page No:321" + ] + }, + { + "cell_type": "code", + "collapsed": false, + "input": [ + "import math\n", + "from __future__ import division\n", + "\n", + "#variable declaration\n", + "G=8 #up gradient\n", + "r=25 #train resistance N/tonne\n", + "M=500 #mass of the electric train in tonne\n", + "n=0.8 #combine effiency of transmission and motor\n", + "#speed time curve characteristics\n", + "t1=60 #characteristic for uniform accelaration at v1 in sec\n", + "alpha=2.5 #given accelaration in km/hr/sec at t1\n", + "t2=5*60 #characteristic for constant speed in sec \n", + "t3=3*60 #characteristic for coasting in sec\n", + "B=3 #dynamic braking deceleration in km/hr/sec\n", + "\n", + "#calculation\n", + "Vm=alpha*t1 #peak voltage\n", + "Fg=9.81*M*G #tractive effort required to overcome the force of gravity\n", + "Fr=M*r #tractive effort required to overcome the train resistance\n", + "F_bc=Fg+Fr #retarding force during coasting\n", + "\n", + "Me=1.1*M\n", + "B_c=F_bc/(277.8*Me) #deceleration during coasting\n", + "V=Vm-B_c*t3 #speed after coasting\n", + "t4=V/B #characteristic for a dynamic braking of 3km/hr/sec\n", + "\n", + "d1=1/2*Vm*t1/3600 #distance covered during accelaration \n", + "d2=Vm*t2/3600 #distance covered during constant speed\n", + "d3=1/2*(Vm+V)*t3/3600 #distance covered coasting\n", + "d4=1/2*V*t4/3600 #distance covered during braking\n", + "D=d1+d2+d3+d4 #distance during stops\n", + "D1=d1+d2\n", + "x=D1/D\n", + "y=1-x\n", + "E=(0.01072*Vm**2/D)*(Me/M)+2.725*G*x+0.2778*r*x #specific energy output\n", + "Eo=E/n #specific energy consumption\n", + "\n", + "#results\n", + "print\"\\n Specific energy consumption is :Eo=\",round(Eo,1),\"Whptpkm\" " + ], + "language": "python", + "metadata": {}, + "outputs": [ + { + "output_type": "stream", + "stream": "stdout", + "text": [ + "\n", + " Specific energy consumption is :Eo= 41.1 Whptpkm\n" + ] + } + ], + "prompt_number": 12 + }, + { + "cell_type": "heading", + "level": 2, + "metadata": {}, + "source": [ + "Example No:10.4,Page No:323" + ] + }, + { + "cell_type": "code", + "collapsed": false, + "input": [ + "import math\n", + "from __future__ import division\n", + "\n", + "#variable declaration\n", + "G=20 #up gradient\n", + "r=25 #train resistance N/tonne\n", + "M=500 #mass of the electric train in tonne\n", + "n=0.8 #combine effiency of transmission and motor\n", + "#speed time curve characteristics\n", + "t1=50 #characteristic for uniform accelaration at v1 in sec\n", + "alpha=3 #given accelaration in km/hr/sec at t1\n", + "t2=10*60 #characteristic for constant speed in sec \n", + "B=2.5 #uniform braking deceleration in kmphs to rest\n", + "\n", + "\n", + "#calculation \n", + "Vm=alpha*t1 #peak voltage\n", + "t3=Vm/B #characteristic for a uniform braking of B=2.5 kmphs\n", + "\n", + "#(i)during accelaration total tractive effort \n", + "Me=1.1*M\n", + "Fta=277.8*Me*alpha-9.81*M*G+M*r #total tractive effort during accelaration\n", + "Da=1/2*Vm*t1/3600 #distance covered during accelaration ,and t1 is in seconds\n", + "Ea=Fta*Da*1000/3600 #energy output during accleration in Wh\n", + "\n", + "#(ii)during uniform speed net tractive effort\n", + "Ftu=-9.81*M*G+M*r #total tractive effort during uniform speed\n", + "#the answer for Ftu in the book is -105220 N which is wrong which leads to the other incorrect answers in the book\n", + "\n", + "Du=Vm*t2/3600 #distance traveled,and t2 is in seconds\n", + "Eu=Ftu*Du*1000/3600 #energy output in Wh\n", + "\n", + "#(iii)during braking net tractive effort\n", + "Ftb=-277.8*Me*B-9.81*M*G+M*r #total tractive effort for the net braking\n", + "Db=1/2*Vm*t3/3600 #distance covered during braking\n", + "Eb=Ftb*Db*1000/3600 #energy output during braking in Wh\n", + "\n", + "E=Ea/n+n*(Eu+Eb) #net energy consumption\n", + "D=Da+Du+Db #total distance traveled\n", + "Eo=E/(M*D) #specific energy consumption\n", + "\n", + "#results \n", + "print\"(i)Energy consumption during accelaration is :Ea :\",round(Ea),\"Wh\"\n", + "print\" There is a slight difference in the answer due to the number of decimal place\"\n", + "print\"\\n(ii)Energy consumption during uniform speed is :Eu :\",round(Eu),\"Wh\" \n", + "print\"\\n(iii)Energy consumption during braking is :Eb :\",round(Eb,1),\"Wh\" \n", + "print\"\\n Net Energy consumption is E :\",round(E,1),\"Wh\" \n", + "print\"\\n Total Distance traveled is D :\",round(D,4),\"km\"\n", + "print\"\\n Specific Energy consumption is Eo :\",round(Eo,2),\"Whptpkm\"\n", + "#answers in the book are incorrect\n" + ], + "language": "python", + "metadata": {}, + "outputs": [ + { + "output_type": "stream", + "stream": "stdout", + "text": [ + "(i)Energy consumption during accelaration is :Ea : 107862.0 Wh\n", + " There is a slight difference in the answer due to the number of decimal place\n", + "\n", + "(ii)Energy consumption during uniform speed is :Eu : -594444.0 Wh\n", + "\n", + "(iii)Energy consumption during braking is :Eb : -162352.4 Wh\n", + "\n", + " Net Energy consumption is E : -470610.4 Wh\n", + "\n", + " Total Distance traveled is D : 27.2917 km\n", + "\n", + " Specific Energy consumption is Eo : -34.49 Whptpkm\n" + ] + } + ], + "prompt_number": 11 + }, + { + "cell_type": "heading", + "level": 2, + "metadata": {}, + "source": [ + "Example No:10.5,Page No:325" + ] + }, + { + "cell_type": "code", + "collapsed": false, + "input": [ + "import math\n", + "from __future__ import division\n", + "\n", + "#variable declaration\n", + "Mm=40 #weight of the motor coach in tonne\n", + "Mt=35 #weight of the trailer in tonne\n", + "u=0.2 #co-efficient of adhesion\n", + "r=30 #train resistance N/tonne\n", + "\n", + "#calculation\n", + "#(a)when the motor to trailer ratio is 1:2\n", + "M=Mm+2*Mt #weight of one unit\n", + "Me=1.1*M\n", + "Md=40 #weight on the driving wheels\n", + "Fm=9810*u*Md #total tractive effort without the wheel\n", + "Ft=Fm #at maximum accelaration \n", + "alpha=(Ft-M*r)/(277.8*Me) #required accelaration since Ft=277.8*u*alpha*M*r\n", + "\n", + "#(b)when the motor to trailer ratio is 1:1\n", + "M=Mm+Mt #weight of one unit\n", + "Me=1.1*M\n", + "Md=40 #weight on the driving wheels\n", + "Fm=9810*u*Md #total tractive effort wihout the wheel\n", + "Ft=Fm #at maximum accelaration \n", + "alpha1=(Ft-M*r)/(277.8*Me) #required accelaration since Ft=277.8*u*alpha*M*r\n", + "\n", + "\n", + "#results\n", + "print\"(a)maximum accelaration on a level track is alpha :\",round(alpha,4),\"kmphps\"\n", + "print\"\\n(b)maximum accelaration when motor to trailer coaches ratio is 1:1 is alpha :\",round(alpha1,3),\"kmphps\"" + ], + "language": "python", + "metadata": {}, + "outputs": [ + { + "output_type": "stream", + "stream": "stdout", + "text": [ + "(a)maximum accelaration on a level track is alpha : 2.2366 kmphps\n", + "\n", + "(b)maximum accelaration when motor to trailer coaches ratio is 1:1 is alpha : 3.326 kmphps\n" + ] + } + ], + "prompt_number": 3 + }, + { + "cell_type": "heading", + "level": 2, + "metadata": {}, + "source": [ + "Example No:10.6,Page No:326" + ] + }, + { + "cell_type": "code", + "collapsed": false, + "input": [ + "import math\n", + "from __future__ import division\n", + "\n", + "#variable declaration\n", + "G=10 #up gradient of the locomotive\n", + "Ml=110 #weight of the locomotive coach in tonne\n", + "Mt=500 #weight of the train in tonne\n", + "r=35 #train resistance N/tonne\n", + "n=0.8 #80% of the locomotive weight is carried by the driving wheels\n", + "alpha=1 #acelaration in kmphps\n", + "\n", + "#calculation\n", + "#when only the 110 tonne locomotive is present\n", + "Md=Ml*n #weight of the motor\n", + "M=Mt+Ml #total mass of the train\n", + "Me=1.1*M\n", + "Ft=277.8*Me*alpha+9.81*M*G+M*r #total tractive effort required to move the train\n", + "Fm=Ft\n", + "u=Fm/(9810*Md) #co-efficient of adhesion ,since Fm=9810*u*Md\n", + "\n", + "#when another locomotive of 70 is added together\n", + "Md=Ml*n+70 # mass of the motor\n", + "M_=Mt+Ml+70 # mass of the train\n", + "Fm=9810*u*Md\n", + "Ft=Fm\n", + "M=Ft/(277.8*1.1*alpha+9.81*G+r) #total mass of the train, since Ft=277.8*Me*alpha+9.81*M*G+M*r\n", + "W=M-M_ #weight of additional bogies to be attached\n", + "\n", + "\n", + "#results\n", + "print\"\\n Given co-efficient of adhesion is:\",round(u,2)\n", + "print\"\\n Weight of additional bogies to be attached is:\",round(W,1),\"T\"" + ], + "language": "python", + "metadata": {}, + "outputs": [ + { + "output_type": "stream", + "stream": "stdout", + "text": [ + "\n", + " Given co-efficient of adhesion is: 0.31\n", + "\n", + " Weight of additional bogies to be attached is: 415.2 T\n" + ] + } + ], + "prompt_number": 16 + }, + { + "cell_type": "heading", + "level": 2, + "metadata": {}, + "source": [ + "Example No:10.7,Page No:327" + ] + }, + { + "cell_type": "code", + "collapsed": false, + "input": [ + "import math\n", + "from __future__ import division\n", + "\n", + "#variable declaration\n", + "Ml=1000 #weight of the empty train in tonne\n", + "Mt=5000 #weight of the fully loaded train in tonne\n", + "G=15 #gradient of the track\n", + "V=30 #maximum speed of the train \n", + "r=40 #train resistance in N/tonne\n", + "u=0.25 #co-efficient of adhesion\n", + "alpha=0.3 #acelaration in kmphps\n", + "\n", + "W=100 #weight of each locomotive\n", + "\n", + "#calculation\n", + "Md=W*n\n", + "Fm=9810*u*Md #total tractive without wheel\n", + "Fb=9.81*(Mt+W*n)*G-(Mt+W*n)*r \n", + "print\"\\nFm=\",Fm\n", + "print\"\\nFb=\",Fb\n", + "print\"\\nequating Fb and Fm we get\"\n", + "n=535750/(245250-10715) #number of locomotive required\n", + "\n", + "#results\n", + "if (n>2) : \n", + " n=3\n", + "print\"\\nThe number of locomotives is n:\",n \n", + "Md=W*n\n", + "M=Ml+W*n\n", + "Ft=277.8*1.1*M*alpha+9.81*M*G+M*r #tractive effore required to move the train\n", + "Fm=9810*0.3*Md\n", + "if (Fm>Ft) :\n", + " print\"\\nThe train can be accelarated with \",n,\"locomotives\"" + ], + "language": "python", + "metadata": {}, + "outputs": [ + { + "ename": "NameError", + "evalue": "name 'n' is not defined", + "output_type": "pyerr", + "traceback": [ + "\u001b[0;31m---------------------------------------------------------------------------\u001b[0m\n\u001b[0;31mNameError\u001b[0m Traceback (most recent call last)", + "\u001b[0;32m<ipython-input-4-e0b827f6bbd9>\u001b[0m in \u001b[0;36m<module>\u001b[0;34m()\u001b[0m\n\u001b[1;32m 14\u001b[0m \u001b[0;34m\u001b[0m\u001b[0m\n\u001b[1;32m 15\u001b[0m \u001b[0;31m#calculation\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0;32m---> 16\u001b[0;31m \u001b[0mMd\u001b[0m\u001b[0;34m=\u001b[0m\u001b[0mW\u001b[0m\u001b[0;34m*\u001b[0m\u001b[0mn\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0m\u001b[1;32m 17\u001b[0m \u001b[0mFm\u001b[0m\u001b[0;34m=\u001b[0m\u001b[0;36m9810\u001b[0m\u001b[0;34m*\u001b[0m\u001b[0mu\u001b[0m\u001b[0;34m*\u001b[0m\u001b[0mMd\u001b[0m \u001b[0;31m#total tractive without wheel\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[1;32m 18\u001b[0m \u001b[0mFb\u001b[0m\u001b[0;34m=\u001b[0m\u001b[0;36m9.81\u001b[0m\u001b[0;34m*\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0mMt\u001b[0m\u001b[0;34m+\u001b[0m\u001b[0mW\u001b[0m\u001b[0;34m*\u001b[0m\u001b[0mn\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m*\u001b[0m\u001b[0mG\u001b[0m\u001b[0;34m-\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0mMt\u001b[0m\u001b[0;34m+\u001b[0m\u001b[0mW\u001b[0m\u001b[0;34m*\u001b[0m\u001b[0mn\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m*\u001b[0m\u001b[0mr\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n", + "\u001b[0;31mNameError\u001b[0m: name 'n' is not defined" + ] + } + ], + "prompt_number": 4 + }, + { + "cell_type": "code", + "collapsed": false, + "input": [], + "language": "python", + "metadata": {}, + "outputs": [] + } + ], + "metadata": {} + } + ] +}
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