Backtracking: a novel strategy for tracking PV systems

A strategy for tracking photovoltaic (PV) arrays is examined. The tracking strategy employs a microprocessor-based controller which commands the PV array to move (referred to as backtrack) such that no interarray beam shading occurs. This strategy will permit higher ground cover ratios (closer interarray spacing), which reduces area-related costs such as land purchase and site preparation. Results indicate that backtracking actually increases the solar energy collection as compared to conventional single-axis tracking with shading losses. Further, since direct shading is eliminated, backtracking allows the use of series-configured panels, which offers benefits of flexibility, optimum fault tolerance, and cost savings associated with bypass and blocking diodes