Chapter 7
LQG Synthesis
©
National Instruments Corporation
7-3
Xmath Interactive Control Design Module
If the decay rate is enabled, it is shown as a vertical line that can
be dragged.
–
A plot showing the poles and zeros of the output weight transfer
function. If weight zero editing is enabled, the zeros can be edited
graphically.
–
A plot showing the magnitude of the output weight transfer
function.
Synthesis Modes
In addition to standard LQG synthesis, the LQG Synthesis
window
supports any combination of three optional features:
•
Integral action
•
Exponential time weighting (guaranteed decay rate)
•
Output weight editing
The synthesis mode is reported in the text at the top of the window. The
toggle
Int Time
(integral action time) button enables and disables integral
action. The
Decay Rate
toggle button controls exponential time weighting.
The
Weight Zero Edit
toggle button enables and disables output weight
editing.
Opening the LQG Synthesis Window
The LQG
window can only accept LQG controllers. If the current
controller is of type LQG (perhaps, from the History
window) and the LQG
window is opened, the current controller is read into the LQG window.
That is, the push buttons and parameters are set to the appropriate values.
If the current controller is not of type LQG, and the user attempts to open
the LQG Synthesis
window, a dialog box appears and warns the user that
proceeding with opening the LQG Synthesis
window will overwrite the
current controller with the LQG controller.
The LQG window remembers its parameter settings. When it is opened, the
parameters will be exactly as they were when the LQG
window was last
closed, or it will be set to default values if the LQG
window has not been
opened in this ICDM session.