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3.12 Nonlinear Simplification Techniques 407
The simulation function must return a list of the AC solutions in the same format as ACAnalysis
returns the result (with the option setting InterpolateResult −> False).
Similarly, you can define your own AC error function instead of the default error function and
specify it as ErrorFunction in the AC mode settings for NonlinearSetup. During the simplification
routines this function is used to calculate the error with the following arguments:
errfct[newval_List, oldval_List, outputsymbols_List]
Pattern for a user-defined AC error function.
Here, newval and oldval are the numerical solutions of the simplified and the original dae system,
outputsymbols is a list of all output symbols.
The error function must return a list of rules {symb
−> err , † † † } which specifies the numerical error
for each output symbol. The default AC error function calculates the maximum relative error.
Instead of specifying the maximum allowed error for output variables for each call to the nonlinear
simplifications routines separately, you can specify global maximum errors for output variables using
the MaxError argument. These values are used if no error value is given in the call to the nonlinear
simplification routine. The value of this argument has to be a list of rules of the form outvar −> error.
Examples
Load Analog Insydes.
Read PSpice netlist.
Set up DAE system.
Get all valid symbols that
can be used as inputs for
NonlinearSetup.
In[1]:= DC, ElementValues −> Symbolic]
Out[3]= DAEDC, 27 27
In[4]:= GetParameters[dae]
Out[4]=
AREA$Q1, AREA$Q2, AREA$Q3, AREA$Q4, BF$Q1, BF$Q2,
BF$Q3, BF$Q4, BR$Q1, BR$Q2, BR$Q3, BR$Q4, GMIN, IB, II,
IS$Q1, IS$Q2, IS$Q3, IS$Q4, TEMP, TNOM, VDC, VLOAD, $k, $q
Get all valid symbols that
can be used as outputs for
NonlinearSetup.
In[5]:= GetVariables[dae]
Out[5]=
V$1, V$3, V$4, V$5, V$OUT, I$BS$Q1, I$CS$Q1,
I$ES$Q1, ib$Q1, ic$Q1, I$BS$Q2, I$CS$Q2, I$ES$Q2,
ib$Q2, ic$Q2, I$BS$Q3, I$CS$Q3, I$ES$Q3, ib$Q3, ic$Q3,
I$BS$Q4, I$CS$Q4, I$ES$Q4, ib$Q4, ic$Q4, I$VLOAD, I$VDC
In the following we choose VLOAD and II as inputs and V$5 and I$VLOAD as outputs, treating dae as
a multi-input/multi-output system. We want to control the DC behavior sweeping VLOAD between