Design of Disturbance Rejection Controllers for a Magnetic Suspension System By: Jon Dunlap Advisor: Dr. Winfred K.N. Anakwa Bradley University December 6, 2005

Summary  Multiple Controllers for Multiple Disturbances  Created In Simulink  xPC Target Box Serving as “Controller Container”  Minimize Steady- State Error, Overshoot and Setting Time  Develop Controller Switching Method

Summary  Goals  Functional Description  Block Diagram  Datasheet  Preliminary Lab Work  Schedule of Tasks  Additional Goals

Goals  Previous Work Classical Controller Without Rejection Works With Step  To Do Multiple Controllers For Various Inputs Use Internal Model Principle Automatic Controller Selection

Functional Description  Host PC using Simulink and xPC software  xPC Target Box with Controllers  Magnetic Suspension System

Block Diagram  Magnetic Suspension System  xPC Target Box

Magnetic Suspension System  Control and Disturbance Drives Current  Current Induces Magnetic Field  Field Suspends Ball  Sensor Translates Location into Voltage

xPC Target Box and Host PC  Using ±10 V ADC and DAC  Download Controllers, Upload Commands  Process Position Data and Passes Control

Datasheet  Disturbance Classes Step Ramp Sinusoidal Square – Triangular  Steady-State Error 50mv  % Overshoot 18%  Settling Time 60ms Previous Work Shows “Useable” Values

Preliminary Lab Work  Disturbance Classes with Plant SS Equations Using Controller Canonical Form DisturbanceState Space Equation k*Cos(a*T) k*Sin(a*T) k-unit step k-unit ramp

Preliminary Lab Work  Tested Classical Controller With Disturbance  Researched Internal Model Principle with Disturbance Rejection Focus

Major Tasks List  Utilize Internal Model Principle To Design Controllers  Implement Controllers In Simulink  Process Simulink Controllers On xPC Target Box  Fine Tune Controllers To Optimize Stability Specifications

Schedule Of Tasks 12/8/ /15/2006  Develop Paper Controllers  Implement Controllers In Simulink 1/19/ /9/2006  Research xPC Implementation  Test Controllers on MSS  Fine Tune Controllers 2/16/ /9/2006  Continue Development of Additional Controllers  Documentation of Controller Methods  Research Disturbance Detection Methods 3/11/ /19/2006  Spring Break  Begin Final Presentation

Additional Goals  Design Disturbance Detection Hardware/Software For Automation Of Controller Usage  Simulink using FFT  Determine Maximum Time Delay Allowable for Stability  Implement on xPC?

Questions?