# Proportional-Derivative-Integral (PID) Control

100 %
0 %

Published on September 23, 2007

Author: guest9006ab

Source: slideshare.net

## Description

A simple, widely used control method. This presentation will provide an introduction to PID controllers, including demonstrations, and practise tuning a controller for a simple system.

From the Un-Distinguished Lecture Series (http://ws.cs.ubc.ca/~udls/). The talk was given Mar. 30, 2007.

Proportional-Integral-Derivative Controller Presented by: Sancho McCann

Simple Control Loop Control Plant Feedback

Examples Control Plant Feedback Throttle Auto-engine Wheel speed Air temp Room temp Thermostat temp Steering direction Car Distance from path Voltage Electric motor Fan speed Fan speed CPU temp CPU temp sensor

Speed control: lookup table 10 kph 3% Throttle 20 kph 6% Throttle 40 kph 20% Throttle 80 kph 50% Throttle 140 kph 100% Throttle

What to do? Goal (set-point): 21 kph How much should you change your throttle?

What to do? Set-point: 80 kph How much should you change your throttle?

Proportional Controller • Far from set point? Change throttle more • Close to set point? Change throttle less quot;control = (setpoint # currentState) • pGain

Example

Proportional-Derivative Control • Approaching set point quickly? Ease off throttle. pTerm = (setPoint quot; currState) • pGain dTerm = (prevState quot; currState) • dGain #control = pTerm + dTerm !

Example

Problem with Derivative Term Enhances noise

Integral Term • Helps state average around the set point • Accumulate historic error • Allow this integral to inform the control decision

Examples

Extremes • What if – P term is too low? – P term is too high? – D term is too low? – D term is too high? – I term is too low? – I term is too high?

Tuning (one manual method) • Start with low pGain (< 1) • Set dGain ~ 100x pGain • Increase dGain until oscillation – Halve until no oscillation reduced • Increase pGain until oscillation – Halve that value • Set iGain very low and increase until a small overshoot is noticeable

Can be complex: Autopilot Heading Roll Aileron

## #control presentations

#### 9 simple ways to change your life forever

 User name: Comment:

## Related pages

### Proportional-Integral-Derivative PID Controls

Proportional Integral Derivative PID Controls Keywords: pid controls, pid controller, pid temperature controller Created Date: 10/14/1999 8:46:00 PM ...

### Basics of PID Control (Proportional+Integral+Derivative ...

PID control represents a significant advancement in the controls industry. It is a very effective technique for providing precise control.

### Proportional-integral-derivative explained | EE Times

Proportional-integral-derivative (PID) control is the most common control algorithm used in industry today. The popularity of PID controllers can be ...

### PID Tuning Tutorial - Metso ExperTune|PlantTriage|Process ...

These settings are rough, assume proper control loop design, ideal or series algorithm and do not apply to all controllers. Use ExperTune's PID Loop ...

### PID Theory Explained - National Instruments: Test ...

PID Theory Explained. ... Classical PID Control by Graham C. Goodwin, Stefan F. Graebe, Mario E. Salgado. Control System Design, Prentice Hall PTR 2.

### PID Control - National Instruments: Test, Measurement, and ...

PID Control. Publish Date: ... Figure 2: Effect of PID Controllers on Closed-Loop System. Note that these correlations may not be exactly accurate, ...

### PID Controllers - General PIDs

PID Controllers - General PIDs ... PID controllers are widely used for control of many kinds of systems. Your goals for this lesson are as follows: