Why do we need it?
To evaluate a sampled function between
sampling points.
Insert a delay Td < T before the sampler.
The Modified z-transform
yd(t)
y( t )
M. Sami Fadali
Professor of Electrical Engineering
University of Nevada
T
yd(kT)
Delay Td
y (t Td
Outline
Time Response of a
Discrete-Time System
Response of linear system.
Convolution theorem.
Impulse response.
z-transfer function.
M. S. Fadali
Professor of EE
UNR
1
Convolution Summation
2
Principle of Superposition
Write input as a weighted sum of
Z-transform Definition
Definition 2.1 Given the causal sequence
then its z-transform is
defined as
The Z-transform
M. Sami Fadali
Professor of Electrical Engineering
UNR
=time delay operator
1
2
Example
Z-transform Definition
Obtain the z-transform of th
Outline
Difference equations as models of
physical systems: example.
Types of difference equations
Difference Equations
Linear.
Nonlinear.
M. Sami Fadali
Professor of Electrical Engineering
UNR
1
2
Example: Tank Control System
DT Model for Digital Con
Outline
Why digital control?
Structure of a typical digital control
system.
Examples of digital control systems.
Digital Control
M. Sami Fadali
Professor of Electrical Engineering
UNR
1
Why Digital Control?
2
Accuracy
Digital control systems are far m