Supercapacitor based RC loop loss circumvention technique to improve the efficiency of photovoltaic inverters

When charging an uncharged capacitor to its maximum voltage V by the pumps Q amount of coulombs, irrespective of the value of the total loop resistance, 1/2QV is dissipated through the loop resistance. If we add a useful load as a part of the RC charging loop's resistance, a significant amount of dissipated energy can be recovered via a useful load, increasing the charging efficiency in the loop. Supercapacitor Assisted Sub Module Inverter (SCASMI) concept is proposed based on the fundamentals of the aforementioned RC loop loss circumvention technique. In this case, a partially precharged Supercapacitor is placed in the RC charging loop with a PV inverter to recover the power wastage. In the SCASMI design, the original specification of the inverter is divided into two identical sub inverter stages with supercapacitor energy circulation front end in a way to minimize the conduction losses by reducing the current through each inverter stage. This paper provides a conceptual background SCASMI concept, implementation details, and experimental results of 24V-240 V prototype SCASMI inverters.