Investigation of multiple-input single-output power conversion for advanced solar cell systems

Abstract

Laterally-Arrayed Multiple-Bandgap (LAMB) solar cells provide the potential for improved energy capture, but require sophisticated interconnection and power conversion. Different topologies for a cell block interconnection were investigated and equations providing the estimated losses in those topologies were derived. The interconnected cell block is used as an input to the Multiple-Input Single-Output (MISO) power converter. Different power converter topologies and control schemes are considered, among which MISO buck converter with Pulse-Width Modulated (PWM) control is selected. For the maximum power extraction, a "Perturb and Observe" (P&O) algorithm is modified to fit the MISO buck converter topology and to account for special operation cases that could arise due to the multiple-input nature of the power converter. To verify the theoretical assumptions, a discrete-component prototype has been built and various experiments performed with it.