Zusammenfassung
When analysing the influence of shade on photovoltaic (PV) systems,
the intuitive assumption is that conversion architectures with more
inverters, such as string- and module-inverters, will have lower
energy losses associated with partial shading of the generators.
However, other phenomena which can affect a systemâs response to
shade, for example, the way in which the inverter performs the maximum
power point tracking (MPPT), mean that modular configurations are
not always the least susceptible to shade effects. We present a case
in which the general tendency of many of the currently available
commercial inverters to remain in local power maxima results in a
string-inverter configuration behaving worse in response to shade
than a central-inverter configuration. Experimental data were collected
throughout 2005 and 2006 from PV plants in Arguedas and Sesma (Spain).
We interpret our observations with theoretical analysis based on
the results of simulation experiments.
Nutzer