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documentation minor glitch

Open max-privato opened this issue 1 year ago • 4 comments

In the information of Diode2Exp the diode formula does not contain the ideality factor m, which is indeed included (and has a significant impact) in the equation section. I would recommend to include it.

I take the opportunity of this ticket to recommend changing the name "Bv" into "Vb", so that it becomes consistent with Vt: thermal voltage and Breakthrough voltage.

max-privato avatar Aug 22 '22 16:08 max-privato

In the information of Diode2Exp the diode formula does not contain the ideality factor m, which is indeed included (and has a significant impact) in the equation section. I would recommend to include it.

In the PV models, e.g., PhotoVoltaics.Components.SimplePhotoVoltaics.SimpleCell, the parameters m and IsdRef are iteration variables in two initial equations and cannot be set independently by the user. The iteration is used to consistently parameterize the PV model.

  final parameter Real m(start = 2, fixed = false) "Ideality factor of diode";
  final parameter Modelica.Units.SI.Current IsdRef(start=1E-4, fixed=false)
    "Reference saturation current of cell";
initial equation 
  IphRef = IsdRef * (exp(moduleData.VocCellRef / m / moduleData.VtCellRef) - 1);
  IphRef = IsdRef * (exp(moduleData.VmpCellRef / m / moduleData.VtCellRef) - 1) + moduleData.ImpRef;

christiankral avatar Oct 17 '22 07:10 christiankral

I take the opportunity of this ticket to recommend changing the name "Bv" into "Vb", so that it becomes consistent with Vt: thermal voltage and Breakthrough voltage.

In the MSL the diode model Modelica.Electrical.Analog.Semiconductors.Diode2 uses the same parameter name Bv. In the PhotoVoltaics library the same name was chosen by intention to keep the connection.

If you propose to change Bv to Vb we should start at the MSL:

  • However, changing the parameter name of a model breaks the compatibility and thus needs a conversion script. So this is a big change and can only be performed in a major release of the MSL.
  • For the same reason I am reluctant to change the parameter name whithout a major release.
  • If you consider the parameter name change important enough you are free to file a ticket at he MSL issue tracker. The implementation will, however, not be done any time soon.

One more comment: Please create two different GitHub tickets for two different requests. Otherwise they cannot be handled independently.

christiankral avatar Oct 17 '22 08:10 christiankral

Thank you for your answers. Regarding the question of m, I mentioned in my comment the information box , where the ideality factor is missing: image

So, I complained that the info box does not correspond to the actual equation. I know that it is not a parameter under the user's control.

Regarding the parameter name, I did not realise that also MSL has Bv. For me it is a bad choice, and I personally would have broken compliancy with MSL in favour of internal coherency between Vt and Vb,... , but that's all, I can live with it.

max-privato avatar Oct 17 '22 17:10 max-privato

The change affects two models:

image

image

christiankral avatar Oct 18 '22 05:10 christiankral