User`s guide

System Interconnections
1-19
System Interconnections
You ca n derive LTI models for various system interconnections ranging from
simple series connections to more complex block diagrams; see “Model
Interconnection Functions” on pa ge 3-16 for more information. Related
commands include
append(sys1,sys2,...) % appends systems inputs and outputs
parallel(sys1,sys2) % general parallel connection
series(sys1,sys2) % general series connection
feedback(sys1,sys2) % feedback loop
lft(sys1,sys2) % LFT interconnection (star product)
connect(sys,q) % state-space model of block diagram
Note that simple parallel and series interconnections can be performed by
direct addition and multiplication, respectively.
When combining LTI models of different types (for example, state-space
sys1
and transfer function sys2), the type of the resultant model is determined by
thesame precedencerulesas forarithmetic operations.See “PrecedenceRules”
on page 2-5 for more information. Specifically, the ranking of the different
types of LTI models from highest to lowest precedence is FRD, SS, ZPK, and
TF.