Influence of the design variables of photovoltaic plants with two-axis solar tracking on the optimization of the tracking and backtracking trajectory

New Omnidirectional Sensor Based on Open-Source Software and Hardware for Tracking and Backtracking of Dual-Axis Solar Trackers in Photovoltaic Plants

“…Furthermore, as a novelty, in this device an ex professo algorithm has been implemented to discriminate at all times those celestial orientations that would imply inter-shading between the collectors of the PV plant. To do this, the device integrates the implementation of tracking and backtracking methodologies characterised and simulated by the authors [ 39 , 40 ] (Fernández-Ahumada et al, 2020b, 2020a) in different photovoltaic plants under irradiance conditions described by empirical models. In this way, the solar trackers do not have to calculate the solar position using astronomical algorithms while taking into account other factors that also affect the incident solar irradiance, such as cloud cover, inter-shading between collectors, etc.…”

“…To achieve the objective described above, the device presented makes a scan of the celestial sphere, during which the incident irradiance measurement is carried out in order to determine the orientation for which this magnitude is maximum. However, as a novelty, the device incorporates a dichotomous algorithm, designed by the authors [ 39 , 40 ] that, prior to the scanning of the celestial sphere, identifies those orientations of the solar trackers for which there would be inter-shading between the collectors. With this, the proposed device restricts the search field for the orientation of maximum irradiance to the set of spatial directions in which there is no inter-shading, which in practice implies a backtracking strategy.…”

“…As mentioned above, the device includes a simple and programmable algorithm in 8-bit AVR RISC microprocessors that, taking into account the characteristics of the PV installation, enables one to know whether a certain orientation of the collectors would imply the partial inter-shading between them for a certain Julian day and a specific solar hour prior to the scanning of the celestial sphere. This algorithm is supported by a novel tracking strategy developed by the authors and the one that is based on Minkowski algebra [ 39 , 40 ].…”

“…The models used for astronomical tracking have traditionally been based on spherical trigonometry [ 31 ]. However, recently, a new paradigm using vector algebra to define the solar movement and that of the trackers can be found in the literature [ 38 , 39 , 40 , 41 , 42 , 43 , 44 , 45 ]. For this, these models use the solar vector , which is a unit vector that is directed to the centre of the solar disk.…”

“…In this line of work, a novel solar tracking strategy with back-tracking has been proposed to optimise the capture of solar irradiance at all times while avoiding inter-shading between collectors in PV plants with dual-axis tracking [ 39 , 40 , 41 ]. In this study, based on empirical models for the characterisation of the hemispheric distribution of irradiance, the authors quantify the increases in solar incidence on collectors at a higher value than 2%.…”