# PVsyst's forum

Welcome on PVsyst's forum.
 It is currently Mon Jun 17, 2019 5:09 pm

 All times are UTC+02:00

 Post new topic  Reply to topic Page 1 of 1 [ 1 post ]
 Print view Previous topic | Next topic
Author Message
 PostPosted: Wed Jul 06, 2016 11:46 pm

Joined: Mon Apr 16, 2012 7:29 pm
Posts: 1586
The backtracking for 2-axis trackers is a very complex problem, and there are several possible different strategies.

In the present time, the PVsyst algorithm is quite insufficient, and you are not advised to use it. It only performs the backtracking in azimuth (with tilt set according to the sun's height), and without going to the "north", i.e. blocking the azimuth to values < 90°.

When the sun goes to higher azimuths, the backtracking should switch to a backtracing in tilt (i.e. the next tracker sees "above" the preceding one). This is not done in PVsyst as we could not find a suited analytical algorithm.

At this stage, one of the problems is: when should the system switch between the azimuth and the tilt strategy? This will induce a discontinuity on the tracking orientation: at a given time, the trackers will suddenly pass from an orientation to another one.
With such a behavior, the system should come back to the Azimuth strategy (at values higher than 90°) symmetrically with respect to azimuth = 90° (West or East).

Now a second problem arises with multi-rows arrays. In this case we should also implement the backtracking between 2 rows (one behind the other), which even may have a shift in E-W direction. Mixing this with the E-W BT strategy becomes a diabolic problem.

We don't see any way of modelling all these behaviours analytically. The only solution would be to implement an ajustment by trys-and-errors, which may become time consuming during the simulation. We did not yet develop such an algorithm in PVsyst up to now.

Top
 Display posts from previous: All posts1 day7 days2 weeks1 month3 months6 months1 year Sort by AuthorPost timeSubject AscendingDescending
 Post new topic  Reply to topic Page 1 of 1 [ 1 post ]

 All times are UTC+02:00

 You cannot post new topics in this forumYou cannot reply to topics in this forumYou cannot edit your posts in this forumYou cannot delete your posts in this forumYou cannot post attachments in this forum

Search for:
 Jump to:  Select a forum ------------------ PVsyst SA Announcements (read only)    Latest news - Bifacial Modelling and 3D Drawing    PVsyst's forum rules FAQ (read only)    Installation and use of PVsyst    Meteo data    PV Components    Shadings and tracking    Simulations : parameters    Simulations : results    Standalone and pumping systems Your questions about PVsyst    Howto    Problems / Bugs    Meteo data    PV Components    Shadings and tracking    Simulations    Suggestions    Tutorials : Feedback and requests Links    PVsyst website    YouTube Channel