Lab 3 - Integral Control and Response Measures

24-451 Feedback Controls

Fall 2000

Introduction

In this lab, you will be using integral control to regulate the speed of the motor-tach system used in Labs 1 and 2. A block diagram showing the closed-loop setup is shown below.

figure50

The controller in this diagram consists of two parts: the integrator/summer and a variable gain. This will require the use of two op-amps rather than just one. The integrator will be used to eliminate steady-state error to a step input and to improve disturbance rejection. The controller gain, Ki will be chosen in lab to meet particular design requirements. Response measures such as settling time, percent overshoot, and steady-state error to both step and ramp inputs will be obtained at each of three gains, as well as disturbance rejection characteristics. Qualitative comparisons will be made between integral control and proportional control over ranges of gains.

Next-Plant Identification

Plant Identification ] Controller Circuit ] Calculate Gains ] Closed Loop Response ] Writeup ]