modelDreal
Electrical real diode of the Modelica bond graph library
Extends from Interfaces.PassiveOnePort (Partial model invoking one bondgraphic connector).
Information
The real diode element is a passive OnePort element. It inherits the effort and flow variables from the passive OnePort. Real diodes are a special class of non-linear resistors.The real diode model consists of the diode itself and an parallel Ohmic resistance R. The diode formula essentially is:
f = Ids*(exp(e/Vt) - 1)
However, if the exponent e/Vt reaches the limit Maxexp, the diode characterisic is linearly continued to avoid overflow.
The causality of the real diode element is free.
Potential variables: e: Bondgraphic effort variable f: Bondgraphic flow variable, normalized positive for flows into the model Parameters: Ids: Saturation current (default value = 1e-6 Amp) Vt: Thermal voltage (default value = 0.04 Volt) Maxexp: Maximum exponent (default value = 15) R: Parallel Ohmic leakage resistance (default value = 1e8 Ohm)
Equations:
f = if (e/Vt > Maxexp) then Ids*(exp(Maxexp)*(1 + e/Vt - Maxexp) - 1) + e/R else Ids*(exp(e/Vt) - 1) + e/R
Parameters
| Type | Name | Default | Description |
|---|---|---|---|
| Modelica.SIunits.Current | Ids | 1.e-6 | Saturation current |
| Modelica.SIunits.Voltage | Vt | 0.04 | Voltage equivalent of temperature (kT/qn) |
| Real | Maxexp | 15 | Max. exponent for linear continuation |
| Modelica.SIunits.Resistance | R | 1.e8 | Parallel Ohmic resistance |
Connectors
| Type | Name | Default | Description |
|---|---|---|---|
| BondLib.Interfaces.BondCon | BondCon1 (from PassiveOnePort) | Bond graph connector |
Components
| Type | Name | Default | Description |
|---|---|---|---|
| Real | e (from PassiveOnePort) | Bondgraphic effort | |
| Real | f (from PassiveOnePort) | Bondgraphic flow |