CONTROL SYSTEM LABORATORY

Objectives:
The objective of Control system laboratory is to identify and understand the different terminology in control engineering along with ability to design a suitable controller for a case specific application.
Outcomes:
Upon the completion of Control System practical course, the student will be able to:
1. Gain strong knowledge of MATLAB software
2. Do various engineering projects.
3. Formulate transfer function for given control system problems.
4. Ability to find time response of given control system model.
5. Plot Root Locus and Bode plots for given control system model
6. Design Lead, Lag, Lead-Lag systems in control systems
7. Ability to design PID controllers for given control system model
Major Facilities available in this laboratory:
1. Computer Setup for simulation.-25nos. ( Matlab, PSPICE, PSIM).
Course covered in this Laboratory:
1. Control System Lab-I (EE-593)
2. Control System Lab-II (EE-693)
Experiments performed in this Laboratory:
1. Familiarization with MAT-Lab control system tool box, MAT-Lab- simulink tool box & PSPICE
2. Determination of Step response for first order & Second order system with unity feedback on CRO & calculation of control system specification like Time constant, % peak overshoot, settling time etc. from the response.
3. Simulation of Step response & Impulse response for type-0, type-1 & Type-2 system with unity feedback using MATLAB & PSPICE.
4. Determination of Root locus, Bode plot, Nyquist plot using MATLAB control system tool box for 2nd order system & determination of different control system specification from the plot.
5. Determination of PI, PD and PID controller action of first order simulated process.
6. Determination of approximate transfer functions experimentally from Bode plot.
7. Evaluation of steady state error, setting time , percentage peak overshoot, gain margin, phase margin with addition of Lead.
8. Study of a practical position control system obtaining closed step responses for gain setting corresponding to over-damped and under-damped responses. Determination of rise time and peak time using individualized components by simulation. Determination of un-damped natural frequency and damping ration from experimental data.
9. Tuning of P, PI and PID controller for first order plant with dead time using Z-N method. Process parameters (time constant and delay/lag) will be provided. The gain of the controller to be computed by using Z-N method. Steady state and transient performance of the closed loop plant to be noted with and without steady disturbances. The theoretical phase margin and gain margin to be calculated manually for each gain setting.
10. Design of Lead, Lag and Lead-Lag compensation circuit for the given plant transfer function. Analyze step response of the system by simulation.
11. Obtain Transfer Function of a given system from State Variable model and vice versa. State variable analysis of a physical system – obtain step response for the system by simulation.
12. State variable analysis using simulation tools. To obtain step response and initial condition response for a single input, two-output system in SV form by simulation.
13. Performance analysis of a discrete time system using simulation tools. Study of closed response of a continuous system with a digital controller and sample and hold circuit by simulation.
14. Study of the effects of nonlinearity in a feedback controlled system using time response. Determination of step response with a limiter nonlinearity introduced into the forward path of 2nd order unity feedback control systems. The open loop plant will have one pole at the origin and other pole will be in LHP or RHP. To verify that
(i) with open loop stable pole, the response is slowed down for larger amplitude input.
(ii) for unstable plant, the closed loop system may become oscillatory with large input amplitude by simulation.
15. Study of effect of nonlinearity in a feedback controlled system using phase plane plots. Determination of phase plane trajectory and possibility of limit cycle of common nonlinearities.