National Instruments 371685C-01 Contents

Contents

About This Manual

Conventions...................................................................................................................vii

Related Documentation..................................................................................................vii

Chapter 1

Overview of the PID Control Toolkit

System Requirements....................................................................................................1-1

Installation Instructions..................................................................................................1-1

Activation Instructions...................................................................................................1-2

PID Control Toolkit Applications..................................................................................1-2

PID Control....................................................................................................................1-3

Chapter 2

PID Algorithms

The PID Algorithm........................................................................................................2-1

Implementing the PID Algorithm with the PID Functions .............................2-2

Gain Scheduling..............................................................................................2-3

The Precise PID Algorithm............................................................................................2-4

Error Calculation.............................................................................................2-4

Proportional Action.........................................................................................2-4

Trapezoidal Integration...................................................................................2-5

The Autotuning Algorithm............................................................................................2-5

Tuning Formulas.............................................................................................2-6

Chapter 3

Using the PID Control Toolkit

Designing a Control Strategy.........................................................................................3-1

Setting Timing.................................................................................................3-1

Tuning Controllers Manually..........................................................................3-2

Using the PID Library....................................................................................................3-4

PID Controller.................................................................................................3-4

Using PID with Autotuning.............................................................................3-6

Using PID with Gain Scheduling....................................................................3-7

Using PID with Lead-Lag...............................................................................3-8

Using PID with Setpoint Profiling..................................................................3-8

Using Ramp Generators..................................................................................3-9