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Chapter 6
Optimizing Design Parameters
Figure 6-7 shows the Problem Specification parameter of the
SIM Optimal Design VI.
Figure 6-7. Specifying the Problem this Example Solves
The System response type parameter in Figure 6-7 shows this example
optimizes parameters for the controller C. The Inequality constraints type
parameter shows this example uses the default calculations for the
inequality constraint envelopes. The Cost type parameter shows this
example minimizes the linear quadratic (LQ) cost function. The following
equation shows this cost function.
T
J LQ =
∫
T
N
e ( t )Wu ( t ) dt ≅
0
∑ ∆t ⋅ e ( n )Wu ( n )
T
n=0
The Weights for cost function parameter in Figure 6-7 shows this example
uses the following weight matrix W:
W = 100 0
0 1
This weight matrix penalizes the control action but emphasizes that this
example minimizes the position error. W also reflects the difference in scale
between the control action range and the output range.
© National Instruments Corporation
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LabVIEW Simulation Module User Manual