This record defines the transfer function between the input signal u and the output signal y by the coefficients of the numerator and denominator polynomials n(s) and d(s) respectively:
n(s) y = ------ * u d(s)
The order of the numerator polynomial can be larger as the order of the denominator polynomial (in such a case, the transfer function can not be transformed to a StateSpace system, but other operations are possible).
Example: The transfer function
2*s+3 y = ----------------- * u 4*s^2 + 5*s + 6
is transformed in the following way in a TransferFunction record:
import Modelica_LinearSystems2.TransferFunction; import Modelica.Utilities.Streams; TransferFunction tf(n={2,3}, d={4,5,6}); print("y = " + TransferFunction.'String'(tf) + " * u"); // prints the following string to the output window: // y = (2*s + 3) / (4*s^2 + 5*s + 6) * u
Name | Description |
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Collection of operators to construct a TransferFunction data record | |
Collection of operators for subtraction of transfer functions | |
Parallel connection of two transfer functions (= inputs are the same, outputs of the two systems are added) | |
Multiply two TransferFunctions (tf1 * tf2) | |
Divide two transfer functions (tf1 / tf2) | |
Integer power of TransferFunction (tf1^k) | |
Check whether two transfer functions are identical | |
Transform TransferFunction into a String representation | |
Generate the transfer function s | |
Package of functions to analyse transfer function represented by a TransferFunction record | |
Package of functions to design transfer function controllers and observers | |
Package of functions to plot transfer function responses | |
Package of functions for conversion of TransferFunction data record | |
Package of functions to generate a TransferFunction data record from imported data | |
Package of internal material of record TransferFunction (for advanced users only) |