Difference between revisions of "Scilab/C4/Control-systems/English-timed"

|Dear Friends,  

 

| Welcome to the spoken tutorial on ''' “Advanced Control of Continuous Time systems” '''

| At the end of this tutorial, you will learn how to

|Define a continuous time system: second and higher order  

 

|Plot response to '''step''' and sine inputs  

 

|Do a '''Bode plot'''  

|Study '''numer''' and ''' denom Scilab functions'''  

 

|Plot ''' poles''' and '''zeros''' of a system  

| To record this tutorial, I am using  

|'''Ubuntu 12.04''' as the operating system with

|'''Scilab 5.3.3''' version  

| Before practising this tutorial, a learner should have basic knowledge of '''Scilab''' and '''control systems.'''   

 

|Let us switch to the ''' Scilab console window. '''

|Here type ''' s equal to poly open paranthesis zero comma open single quote s close single quote close paranthesis''' , press '''Enter.'''  

 

 

 

|The output is ''' 's'. '''   

 

|There is another way to define ''' 's' ''' as '''continuous time complex variable. '''

 

| ''' s equal to percentage s''', press '''Enter.'''  

 

 

|Let us study the ''' syslin Scilab command.'''  

 

|Use the '''Scilab''' function ''' ’syslin’ ''' to define the continuous time system.  

 

 

||''' G of s is equal to 2 over 9 plus 2 s plus s square'''

 

 

|Use ''' csim''' with '''step''' option, to obtain ''' the step response''' and then plot the step response.  

 

 

||Here type:''' sys capital G equal to syslin open paranthesis open single quote c close single quote comma two divide by open paranthesis s square plus two asterik s plus nine close paranthesis close paranthesis '''

 

| Here '''c''' is used as we are defining a continuous time system.  

 

| Press '''Enter'''

|'''2 over 9 plus 2 s plus s square'''  

 

| Then type ''' t equal to zero colon zero point one colon ten semicolon'''  

 

 

|Then type  ''' y one is equal to c sim open paranthesis open single quote step close single quote comma t comma sys capital G close the paranthesis semicolon'''  

|Press '''Enter. '''

 

 

|Then type ''' plot open paranthesis t comma y one close paranthesis semicolon'''  

|Press ''' Enter.'''

|The output will display the ''' step response of the given second order system.'''

|Let us study the ''' Second Order system response for sine input.'''  

 

 

|''' Sine inputs''' can easily be given as inputs to a  ''' second order system to a continuous time system.'''  

 

|| Type ''' U two is equal to sine open paranthesis t close paranthesis semicolon'''  

| Press ''' Enter. '''

 

 

 

|Then type ''' y two is equal to c sim open paranthesis u two comma t comma sys capital G close the bracket semicolon '''

 

 

 

| Press ''' Enter'''

 

||Here we are using ''' sysG, the continuous time second order system''' we had defined earlier.  

 

 

|'Then type '''plot open paranthesis t comma open square bracket u two semicolon y two close square bracket close paranthesis '''

 

 

|'Press '''Enter.'''  

 

 

| This plot shows the '''response of the system''' to a '''step input''' and '''sine input.''' It is called the '''response plot. '''

 

|As expected, the output is also a ''' sine wave,''' and  

 

 

|there is a '''phase lag''' between the input and output

 

|'''Amplitude''' is different for the input and the output, as it is being passed through a '''transfer''' function.  

 

 

 

|Let us plot ''' bode plot of 2 over 9 plus 2 s plus s square'''

 

|Please note command ''''f r e q'''' is a '''Scilab''' command for '''frequency response.'''

 

| Do not use '''f r e q as a variable !!'''  

 

 

|''' f r is equal to open square bracket zero point zero one colon zero point one colon ten close square bracket semicolon. '''

 

| Press '''Enter. '''

 

|Then type '''bode open paranthesis sys capital G comma fr close paranthesis '''

 

 

 

| and press ''Enter.'''  

 

 

 

| The '''bode plot''' is shown  

 

|We have an ''' over-damped system p equal to s square plus nine s plus nine '''

 

 

|Type this on your ''' console.'''  

 

|''' p is equal to s square plus nine asterik s plus nine'''

 

|and then press ''' Enter. '''

 

|Then type this on your ''' console.'''  

 

|''' sys two is equal to syslin open paranthesis open single quote c close single quote comma nine divided by p close paranthesis '''

 

|Then type '''t equal to zero colon zero point one colon ten semicolon '''

 

|Press ''' Enter.'''  

 

 

|''' y is equal to c sim open paranthesis open single quote step close single quote comma t comma sys two close the paranthesis semicolon'''

 

|Then type ''' plot open paranthesis t comma y close paranthesis'''

 

|Press ''' Enter.'''

 

|The ''' response plot for over damped system is shown.'''  

 

|To find the ''' roots of p''' type this on your '''console - '''

 

|''' Roots of p''' and press '''Enter.'''  

 

 

|These '''roots''' are the poles of the system '''sys two'''

 

|Please plot '''Step response''' for this system along similar lines, as for '''over damped system. '''

 

|Switch to ''' Scilab console. ;'''

 

|Type on  '''console'''

 

|''' sys three is equal to syslin open paranthesis open single quote c close single quote comma s plus six comma s square plus six asterik s plus nineteen close paranthesis'''

 

|Press '''Enter'''  

 

 

|Another way of defining a system, is to type  

 

|'''g is equal to open paranthesis s plus six close paranthesis divided by open paranthesis s square plus six asterik s plus nineteen close paranthesis'''

 

 

|Then type this on your '''console'''

 

|'''sys four is equal to syslin open paranthesis open single quote c close single quote comma g close paranthesis '''

 

|'''six plus s over 19 plus six s plus s square '''

 

 

|The variable '''’sys’ is of type ’rational’. '''

 

|'''Sys of two , numer of sys or numer of g''' gives the numerator.  

 

 

|The denominator can be calculated using '''sys(3) or denom of sys functions. '''

 

 

|The poles and zeros of the system can be plotted using p l z r function.  

 

|The syntax is p l z r of sys  

 

 

|The plot shows x for poles and circles for zeros.  

 

 

|Type this on your Scilab console.

 

|sys three open paranthesis two close paranthesis

 

 

|Press Enter.

 

|Otherwise, you can type  

 

 

|numer open paranthesis sys three close paranthesis.

 

|Press Enter

 

|The numerator of system three is shown.  

 

|To get the denominator, type  

 

|sys three open paranthesis three close paranthesis. Press Enter.  

 

 

|You can also type denom open paranthesis sys three close paranthesis.

 

|Then type p l z r open paranthesis sys three close paranthesis.

 

|The output graph plots the poles and zeros.  

 

|It shows cross and circle' for poles and zeros of the system respectively.  

 

 

|Plot step and sinusoidal responses.  

 

|Extract poles and zeros of a transfer function.  

 

| Watch the video available at the following link

 

| It summarises the Spoken Tutorial project  

 

 

 

||If you do not have good bandwidth, you can download and watch it  

 

||The spoken tutorial project Team

 

||Conducts workshops using spoken tutorials  

 

 

||Gives certificates to those who pass an online test  

 

 

||For more details, please write to contact@spoken-tutorial.org  

 

 

|Spoken Tutorial Project is a part of the Talk to a Teacher project  

 

 

 

|More information on this mission is available at spoken-tutorial.org/NMEICT-Intro

 

|This is Ashwini Patil signing off.

 

| Thank you for joining Good Bye.