Photovoltaic (PV) single-phase string inverter

When it comes to renewable energy, solar panels have been at the forefront of developments for some time. However there is still an efficiency question over their performance, with even the latest photovoltaic (PV) technologies delivering around 20% efficiency when it comes to converting sunlight into electricity. Residential and small commercial solar installations up to about 5 kW, tend to use a multiple strings of 360 W to 400 W panels. In both the DC boost stage and AC inversion stage, GaN FETs provide an significant boost to overall system efficiency and a reduction in inverter size, weight and cost.

Block diagrams

Highlighted components are Nexperia focus products

Design considerations

  • Choice of topology for DC/DC and DC/AC conversion, but isolated half-bridge boost and full bridge inverter offer the highest efficiencies
  • Need to ensure a optimal gain ratio on the half-bridge boost and a 50% duty cycle
  • Despite IGBTs dominating the DC/AC stage due to their very low cost, GaN FETs allow for higher efficiency and smaller line filters.

DFN0606 MOSFET:小封装里的高效器件



Quick Learning - Benefits of using power GaN FETs in Solar inverters

Join Ilian as he explains the differences between an IGBT based DC/AC converter and a GaN FET based DC/AC converter, highlighting the benefits GaN brings.