A Common Ground (CG) Switched Capacitor Multilevel Inverter (SCMLI) with An Additional Charge Pump Cell Fitted for Photovoltaics - Supplied Energy Systems

A CG – SCMLI with an additional charge pump cell is proposed. This cell, supplied often by the source, frequently recharges the other capacitors or replaces them in transferring energy to the load. Thus, all the capacitors are recharged with a high frequency. The input source keeps pumping energy continuously. As a result, (a) the capacitors continuous discharging time intervals are greatly reduced, allowing for a design with very small value (μF) capacitances; and (b) the input current becomes continuous. The common input source – load ground effectively annihilates the solar cells leakage current. The above characteristics are perfect for PV applications. A prototype of 240 W, 7-levels inverter, of small size and low weight was built and tested. The measured nominal efficiency is 97.7%.