unilhexio

Ok. Thererfore, I understand that it is a more accurate calculation to do the simulation by constructing the 3-D scene instead by defining the "Orientation" dialog. In my opinion, the text from PVsyst help that I have quoted before (Near shadings: Backtracking strategy), may be improved taking this into account. Thanks a lot for your reply!

Thanks a lot for your reply, André.

In the following picture, the near shading for single axis tracker N-S with backtracking is shown. There are not any other shading object, as can be seen in the diagram below: http://sia1.subirimagenes.net/img/2013/09/26/130926104851235384.jpg In the following picture, the loss diagram is shown: http://sia1.subirimagenes.net/img/2013/09/26/130926104850599410.jpg I know that it is not necessary to draw the scene. As it is mentioned in PVsyst help "As there are no shadings (except when the sun is behind the plane), the 3D construction is not really necessary. The "Orientation" dialog is sufficient for fully defining a Backtracking system for the simulation. "... but the result is different if I define only the orientation dialog: http://sia1.subirimagenes.net/img/2013/09/26/13092610542830347.jpg In PVsyst v5 both simulations lead to the same results. This is an inconvenience if the 3-D must be done if we have any other shading object in our scene.

This is the parameter I am talking about: http://sia1.subirimagenes.net/img/2013/09/25/130925062938735518.jpg I have tried to reinstall the software, but the problem persists and whatever introduced value is not taken into account. Finally, I have observed that if I change the value, exit PVsyst and open PVsyst again, the value is saved and everything it's ok. :shock:

Hi, I have found a possible bug in PVsyst v6: editing the Hidden PVsyst parameter, I have changed the value of "Limit overload loss for design" to a 5% value (default value for this parameter is 3%), as I did before in PVsyst v5. When I'm trying to simulate with an overload value over 3%, the following message is shown: "The inverter power is strongly undersized". The bug is that if I close PVsyst and run it again, the value of "Limit overload loss for design" has come back to 3% again, and other values are never taken into account, so I can not simulate my PV plant if this value is exceeded. Kind regards.

Hi, I'm simulating a single axis tracker system wih backtracking in PVsyst 6. The scene only contains the trackers: no buildings or shading objects. When PVsyst is computing the shadings diagram, the ressult is no shadings, as expected. But in the final report, a 2% of near shadings losses is shown. It never happened to me in the previous PVsyst v5 version. In fact, I have been simulating this project in v5 correctly. What can be the problem? Thanks in advance.

Hi, May be that in your case the global tilted irradiation is higher for 10º tilt.

For a large number of objects defined in "Near shading definition", if we want to print a report of our 3-D scene there is a limitation of only one page and the only thing that will be printed is an uncomplete list of objects, without the prespective model. Also, I can say that the option "keep this view for report" does not work properly; for large PV Plants the result is that no image appears in the final report or it appears mismatched. It would be nice to remove theses restrictions. Kind regards!

Thanks for you reply, André.

Hi! I have detected the following possible bug: when exporting to a file the Energy injected into Grid (hourly data) I obtain these values (for example): 30/11/1990 4:00 0 30/11/1990 5:00 0 30/11/1990 6:00 0 30/11/1990 7:00 137965 30/11/1990 8:00 441761 30/11/1990 9:00 683361 30/11/1990 10:00 866946 30/11/1990 11:00 1131088 30/11/1990 12:00 824554 30/11/1990 13:00 444963 30/11/1990 14:00 364957 30/11/1990 15:00 430901 30/11/1990 16:00 135101 30/11/1990 17:00 -3247.8102 30/11/1990 18:00 0 30/11/1990 19:00 0 30/11/1990 20:00 0 namely, there are values below zero although "night disconnect" is marked in external transformer detailed losses (ohmic losses). This occurs randomly and always in the beginning and final hours of a day. I have realized this problem at least from version 5.57. Moreover, the total sum of Energy Injected into Grid including negative values, is employed in order to calculate the performance ratio and the specific production of the PV Plant. Is this a real Bug or am I doing something wrongly? Kind regards.