How to design a pid controller in matlab manual tuning method. The minor loop is designed to change the open loop poles and open loop transientresponse. Mar, 2012 how to plot the root locus of transfer function in matlab urban school. The transfer fcn lead or lag block implements a discretetime lead or lag compensator of the input. Its objectives includes, among other things, the modeling and simulation study of the use of svc in the nigeria 31bus 330 kv power transmission network, using. Pdf lead and lag compensators with complex poles and zeros. Discretetime or continuoustime leadlag compensator simulink. Examples functions and other reference release notes pdf documentation.
Build the simulink model and once completed, connect to target. Matlab is an interactive program for numerical computation and data visualization. Process parameters time constant and delaylag will be provided. Design via root locus using the systems poles and the pole and zero of the ideal integral compensator, the summation of. Design and comparison of a multipurpose pid controller using. Compensator design for speed control of dc motor by root. This will lead to automatic control of position of the dc motor without manual interference. How to plot the root locus of transfer function in matlab.
By using this method, the designer can predict the effects on the location of the closed loop poles of varying the gain value or adding openloop poles andor open loop zeros. With this design tool, control engineers would be able to rapidly design nonlinear lead andor lag compensators. Three di erent compensators are designed and analyzed based on phase and gain. State space root locus sketching rules negative feedback rule 1. To interactively shape the openloop response using control system designer, use the bode editor. Keywords mathematical model, phase lead and phase lag compensator, desired. Then we present a design technique for the lead compensator by use of the bode diagram. The ball and beam system is laboratory equipment with high nonlinearity in its dynamics. Using these editors, you can interactively tune the gain, poles, and zeros of the compensator, while simultaneously visualizing the effect on the set of plants. A firstorder phase lead compensator can also be designed using a frequency reponse approach. The procedure of lag compensator design is same as lead only the change in procedure is of calculations for poles and zeros. Designs are based on a target gain cross over frequency and a target phase margin.
Lead lag compensators example with design so that dominant closed loop poles are at the sse is 0. Pdf design of a leadlag compensator for position loop. In these editors, interactively modify the gain, poles, and zeros of the compensator. Analyze and interpret stability of the system through root locus, bode plot and nyquist plot. Design via root locus california state university, sacramento. Run the command by entering it in the matlab command window. In this paper compensator is designed by using matlab programming. Design of phase lead and phase lag compensator for pitch. Method design a lead compensator to place the dominant poles at the desired places while neglecting the effects of the lag compensator. Simulink modeling page we generated two different dc motor models in simulink. You can design the compensator by shaping the openloop frequency response in either the bode editor or nichols editor.
The controller design process called controller the mathematical model of a pitch controller is calculated. To satisfy the tracking requirement of zero steadystate error, add an integrator to the compensator. A designer must know how to generate the root loci of the closed loop system both by hand and with a computer e. In the limit as k infinity, the poles of the closedloop system are bs 0 or the zeros of hs. Jun 14, 2015 control system design with control system tuning app. I took one whole day to figure out how to write a program to designa lead compensator with rot locus in matlab. Depending on the effect desired, one or more lead and lag compensators may be used in various combinations. Finally, the result of phase lead and phase led compensator is presented by using matlabgui. A lead compensator in frequency response form is given by the following. First design the minor loop then design the major loop. In the editor, you can adjust the openloop bandwidth and design to gain and phase. Design via root locus elec304alper erdogan 1 1 lecture 1.
Students will have the knowledge on matlab and scilab tools. Pdf computer aided design of lead compensator using root. Phase lag compensator design using bode plotsandphase lead compensator design using bode plots, theses notes will concentrate on the use of those two designs together. As you may have seen in the continuous lead and lag compensator design tutorial, a lead compensator can increase the stability or response speed of a system.
Lead and lag compensators with complex poles and zeros design formulas for modeling and loop shaping. There is nothing you have to do with this simulink model other than build once. Design and implementation of ball and beam system using pid. In the limit as k 0, the poles of the closedloop system are as 0 or the poles of hs. In 11, using matlabsimulink software simulation was done to demonstrate the performance of the system for each of the facts. For a servo plant with an integrator, analytical tuning formulas for phase lead compensators with both gain and phase margin specifications are derived in this paper. Assistant professor of laki reddy balireddy college of engineering, mylavaram. This method can be extended to more complicated design problems, such as two phaselag lead compensators connected in series. Position control of dc motor by compensating strategies. Comparing with other tuning methods, this method is simple with a short tuning time.
Pdf this paper introduce the lead,lag,laglead compensator design of root locus using single composite matlab programme. Run matlab and change your workspace to your folder on the c. Design feedback compensators to achieve a set of desired closed loop system characteristics and design a compensator in the frequency domain to meet specific design requirements using a lead compensator, lag compensator, or lead lag compensator. Lead, one pole and one zero on the negative real axis, with the zero having a. Rlocus analysis design nyu tandon school of engineering. You can add dynamics and modify compensator parameters using the compensator editor or using the graphical bode editor, root locus editor, or nichols editor plots compensator editor. Determine the transfer function of the lead compensator. We will now employ these models within simulink to simulate the system response and design different approaches to control. The main ideas of the paper are to model the ball and beam system considering nonlinear factors and coupling effect and to design proportional integral derivative pid controller to control the ball position. Design compensator for systems represented by frequency. Consider compensation as adding poles and zeros to feedback section for the equivalent system. Lead compensation tutorial resources in control education. Design compensator using automated pid tuning and graphical bode design. The procedure for designing the laglead compensator is presented in section ii.
The reader is referred to those notes for details on the individual design procedures. Design a phase lead compensator which provides a maximum phase angle of 30at 500hz. Laboratory instruction manual jis college of engineering. Unit b involves compensator design for systems with realistic parameters involving practical speci. As the openloop gain, k, of a control system varies over a continuous range of values, the root locus diagram shows the trajectories of the closedloop poles of the feedback system. Execute time response analysis of a second order control system using matlab 2. Compensators design utilizing the frequency response. Design a laglead compensator such that the system will operate. Find range of gain k for stability using root locus plot duration. These results can then be marked authorized by using matlab simulink and manual calculations. Analyze toque speed characteristics of dc and ac servomotors. Control tutorials for matlab and simulink motor speed. Design leadlag compensator using sisotool in matlab.
The purpose of compensator design generally is to satisfy both transient and steadystate speci. Compensator design for a set of plant models matlab. Matlab is a highperformance language for technical computing. The proposed phase lead and phase lag compensator design can be used for any system that the mathematical model have been known to meet desired specifications. Position control using p, pd and lead control print both the root locus and the time trace with a marker at the rst peak labeling them 7. Design via root locus elec304alper erdogan 1 1 lecture.
Bode diagram design is an interactive graphical method of modifying a compensator to achieve a specific openloop response loop shaping. Gain a better understanding of root locus plots using matlab. I am working on position control of a dc motor connected to a pulley and getting position feedback by means of a potentiometer. This has been the most difficult part for me since i started writting this series. Design of compensators for speed control of dc motor by. Control system design using bode plot lead, lag and leadlag. Design and analysis portland state university department of electrical and computer engineering portland, oregon, usa december 30, 2009 abstract this paper discusses the design of a compensator for the buck dc switching converter. The user can simulate the phase lead or phase lag program by clicking these two. Simulation results under two typical cases show that this method is general, too. The root locus plotted by using matlab on the figure window, click edit copy.
It ties the creation of user interfaces called front panel into the development panel cycle. Root locus design is a common control system design technique in which you edit the compensator gain, poles, and zeros in the root locus diagram. Validate your compensator design by simulating the nonlinear simulink model with the tuned controller parameters. The objective of this lab is to introduce to the students the design and implementation of. Phase lead compensator design using bode plots, a slightly di. Design lag, lead, leadlag compensators and verify experimental results using matlab. Then the manual observation and record will be evaluated for 50% of. I deduced the transfer function and designed a pid using the manual method and zn. Prior to carrying out these steps, it is assumed that all transient response speci. The following steps outline the procedure that will be used to design the special lag compensator using root locus methods in order to satisfy steadystate speci. Sumofsquares design method for fourparameter laglead.
Design of lead and lag compensators using frequency domain techniques prof. Pdf this paper introduce the lead,lag,laglead compensator design of root locus using single. Abstractthis paper describes design of phase lead and phase lag compensator for pitch controller of aircraft. Using the systems original poles and assuming a lead compensator zero at 1. Design of a leadlag compensator for position loop control of a gimballed payload. Compensators design utilizing the frequency response methods. Start by evaluating t determine the pole and zero location of the lead compensator. Design feedback compensators to achieve a set of desired closed loop system characteristics and design a compensator in the frequency domain to meet specific design requirements using a lead compensator, lag compensator, or leadlag compensator. Compensator design to improve transient performance using. In matlab a phase lead compensator in root locus form is implemented using the following commands where kc, z, and p are defined. To open the compensator editor dialog box, in control system designer, in an editor plot area, rightclick and select edit compensator. The motor is given a square wave for obtaining a step response.
This method can be extended to more complicated design problems, such as two phaselaglead compensators connected in series. Design singleinput, singleoutput siso controllers matlab. Using control system designer, you can manually edit compensator. Design via root locus elec304alper erdogan 1 35 two approaches for feedback compensation 1. Control system design using bode plot lead, lag and leadlag controllers. Develop a plc program for an automatic control system of a medium degree of complexity. Comment on what you could do to ensure you meet this requirement. This is useful when selecting new phase margins in compensator design. We will start from the frequency domain design using bode plot. A fourparameter laglead compensator is presented, which formulates the design problem into a polynomial function optimization problem solved by using sos techniques. Design and implementation of ball and beam system using. Consider of lead compensator having the following transfer function. Ee302 phase lead compensators depiero compensator networks are typically implemented as electrical circuits in the feedforward path of a control system. Design of lead and lag compensators using frequency.
The leadlag discrete or continuous block implements a leadlag compensator in conformance with ieee 421. Margins 12 mechanistic lead compensation design with matlab. Evaluate the steady state performance of the lead compensated system to. Write a matlab code to design a phaselead compensator for the system. Design three lead compensators for the system to reduce. A known nonlinear compensator design approach is adapted to allow design of nonlinear lead andor lag compensators, and a number of matlab functions are developed that automate the compensator design procedure. In this page, you will learn how to design digital lead and lag compensators using the rootlocus design method. The examples and plots presented here are all done. Lead lag compensator using either root locus or frequency response. Compensator design to improve transient performance using root locus prof. The instantaneous gain of the compensator is 1, and the dc gain is equal to 1z1p, where z is the zero and p is the pole of the compensator. Introduction to matlab lag compensator with bode plot lag compensator with root locus so far we have seen the design of lag compensators, now we move on to lead compensators which help in improving the transient response.
Design leadlag compensator using sisotool in matlab arabic abdo hamdy metwaly. Design lag, lead, lead lag compensators and verify experimental results using matlab. Position control using p, pd and lead control startup. During any system functioning much nonlinearity such as dead zone. No matter what we pick k to be, the closedloop system must always have n poles, where n is the. Shows how matlab tools can be used quickly and efficiently to implement, and illustrate, the mechanistic design procedure for a lead compensator. Use matlab to compare the responses with a simple gain design, a lag design and a lead design and comment on what you find.
For the phaselead compensator the design procedure has the following steps. The lead compensator is an electrical network which produces a sinusoidal output having phase lead when a sinusoidal input is applied. Lead or phaselead compensator using frequency response. Lead or phase lead compensator using frequency response. Then all of design parameters of compensator and design steps are implemented using matlab without. In the root locus design approach presented here, these two tasks are approached separately. In matlab a phaselead compensator in root locus form is implemented using the following commands where kc, z, and p are defined.
You should see on the encoder scopes that the square wave reference signals appear. Compensators, computer aided design, desired response specifications, matlab, root locus. Generate the bode plot of your lead compensator and verify that you have the desired phase margin at the desired frequency. Control system design by frequency response using matlab. Achieve your design goals by manually editing compensator poles, zeros, and gains. Design a phase lead compensator which provides a maximum phase angle of. Position control of dc motor by compensating strategies s prem kumar1 1 1j v pavan chand b pangedaiah 1. The control system designer app lets you design singleinput, singleoutput siso controllers for feedback systems modeled in matlab or simulink requires simulink control design software. Wonhee kim energy system engineering, chungang university.
Now i need to design a phase lead and phase lag compensator. The gain of the controller to be computed by using zn. Using matlab, obtain the partial fraction expansion of fs. The conjugate poles p 1 and p 2 of the complex lead compensator lie at the intersection. Pdf this paper introduce the lead,lag,lag lead compensator design of root locus using single composite matlab programme. A fourparameter lag lead compensator is presented, which formulates the design problem into a polynomial function optimization problem solved by using sos techniques. Leadlag compensator using either root locus or frequency response. For those who have followed my previous posts will know by now what the. The frequencyresponse design method therefore by applying the lead compensator.