Solar Panel Mains Inverter with Improved Efficiency

A photovoltaic (PV) 2-stage micro-inverter is introduced with a separate DC/DC converter and DC/AC inverter. These two parts are connected by a DC-link that incorporates a low voltage energy buffer that is suitable for operation with a capacitor or low voltage battery. A novel maximum power point tracking (MPPT) method is applied to the DC/DC converter with improved efficiency and stability. The topology of the DC/AC converter is developed with the goal of reducing cost and device size. The converter design is developed with an integrated PWM high-frequency (20kHz) transformer to boost voltage to grid level before smoothing with an LC filter for 50Hz output. Experimental results of the MPPT efficiency and the DC/AC topology are presented to verify operation.