modelSmoothStep
Extends from Modelica.Icons.Example (Icon for runnable examples).
Information
This example shows a comparison of a multi-segment OLine model with the distributed-parameter line model TLine.
If resistances and conductances are negligible, with OLine the results should become closer and closer as the number of segments increases.
Suggested tests:
Steep step
Use the model as it is (it has firstOrder.T=1e-9 s) and compare R1.v, R5.v, R50.v, Rdistr.v: Rdistr.v is the ideal voltage of the receiving-end resistor for a lossless line, while the others are approximations with 1, 5, 50 cascaded segment models.
The step in this case is nearly ideal, and therefore is a very tough test for cascaded segments, and in fact they are not very good in approximating the real line behaviour.
Smoother step
Repeat the simulation using firstOrder.T=20e-6 s. You will see that the OLine compliance with the reference result given by TLine is much better, and 50 segments are probably adequate for several applications; in comparison with, they add the option of evaluating losses.
Parameters
| Type | Name | Default | Description |
|---|---|---|---|
| SI.Resistance | Rload | 1000 | Load resistance |
| Real | r1 | 1e-6 | Resistance per meter |
| Real | g1 | 1e-12 | Conductance per meter |
| Real | l1 | 1e-6 | Inductance per meter |
| Real | c1 | 1e-11 | Capacitance per meter |
| SI.Length | len | 100e3 | Length of line |
| Integer | N1 | 1 | Number of lumped segments of oline1 |
| Integer | N5 | 5 | Number of lumped segments of oline5 |
| Integer | N50 | 50 | Number of lumped segments of oline50 |
| SI.Velocity | c | 1/sqrt(l1*c1) | Speed of EM wave |
| SI.Time | td | len/c | Transmission delay |
| SI.Impedance | z0 | sqrt(l1/c1) | Characteristic impedance for very high frequency |
Components
Revisions
- May, 2021 implemented by Massimo Ceraolo, University of Pisa