Photovoltaic panels have a non-linear current-voltage characteristics to produce the maximum power at only one point called the maximum power point. In the case of the uniform illumination a single solar panel shows only one maximum power, which is also the global maximum power point. In the case an irregularly illuminated photovoltaic panel many local maxima on the power-voltage curve can be observed and only one of them is the global maximum. The proposed algorithm detects whether a solar panel is in the uniform insolation conditions. Then an appropriate strategy of tracking the maximum power point is taken using a decision algorithm. The proposed method is simulated in the environment created by the authors, which allows to stimulate photovoltaic panels in real conditions of lighting, temperature and shading.

The studied collecting electrodes for electrostatic precipitators are cold-rolled formed. Here Sigma 750 open section was manufactured of DC01 steel grade. Length of the electrodes ranged from 8 to 13 meters, all were thin-walled of 1.5 mm. Tolerance of their manufacture is strictly set. A database of material properties, chemical composition, and a set of final tolerance of manufactured profiles has been collected. At first basic statistics for the data has been done. Finally statistical relation between the material composition and profile geometrical tolerance has been studied, next between the material mechanical properties and profile geometrical tolerance has been examined.