Simulink Control Design™ - MathWorks

Linearization of Models with Delays

This example shows how to linearize a Simulink model with delays in it.

Linearization of Models with Continuous Delays

You can linearize a Simulink model with continuous time delays blocks such as the

Transport Delay, Variable Transport Delay, and Variable Time Delay using one of the

following options:

• Use a Pade approximations of the delays to get a rational linear system through
  linearizations.


• Compute a linearization where the delay is exactly represented. Use this option when
  you need accurate simulation and frequency responses from a linearized model and
  when assessing the accuracy of Pade approximation.

By default, Simulink Control Design uses Pade approximations of the delay blocks in a

Simulink model.

To open the engine speed model used in this example, type

model = 'scdspeed';

open_system(model);

The engine speed model contains a Variable Transport Delay block named dM/dt in the

subsystem Induction to Power Stroke Delay. For convenience you can store the path to the

block in a MATLAB variable by typing

2 Linearization