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National Instruments Corporation
8-1
Xmath Interactive Control Design Module
8
H-Infinity Synthesis
This chapter describes the H
∞
Synthesis
window used for SISO plants.
The H
∞
Synthesis
window is used to synthesize a central controller. Such
controllers are sometimes called linear exponential quadratic Gaussian
(LEQG) or minimum entropy controllers. For a description of the MIMO
Synthesis window, refer to Chapter 12,
.
H-Infinity Synthesis Window Anatomy
The H
∞
Synthesis
window is shown in Figure 8-1. From top to bottom,
it consists of:
•
A menu bar with entries
Special
,
Edit
,
View
, and
Help
.
•
A control panel for changing the three design parameters:
–
H
∞
performance level (
γ
)
–
Control cost parameter (
ρ
)
–
Sensor noise parameter (
ν
)
These parameters are described in greater detail later in this chapter.
•
A control panel used to edit the output weight transfer function
(described in the
section).
•
A plotting area that contains four plots:
–
A singular value plot of the normalized closed-loop transfer
matrix along with the parameter
γ
, which can be grabbed and
dragged to a new value. If a lower bound on the minimal value
of
γ
is known, it also is displayed.
–
A plot that shows the closed-loop poles.
–
A plot that shows the poles and zeros of the output weight transfer
function. When
Weight Zero Edit
is enabled, the user can grab
and drag the zeros to new locations.
–
A plot that shows the magnitude of the output weight transfer
function.