HIGH EFFICIENCY WIDE LOAD RANGE BUCK/BOOST/BRIDGE PHOTOVOLTAIC MICRO-CONVERTER

摘要

Series strings of photovoltaic (PV) modules with integrated dc-dc microconverters that can function in buck, boost, or an intermediate bridge mode based on the load can harvest more energy than conventional central-inverter architectures, especially when the arrays are partially shaded or when the modules are mismatched. The integrated multi-mode dc-dc converter includes a maximum power point tracking (MPPT) algorithm that can track the true MPP, even when a PV module becomes partially-shaded, without scanning the entire output voltage range. The algorithm compares power levels only at a voltage that occurs when a bypass diode bypasses a portion of an associated PV module, and multiples thereof.