Micro inverters are becoming increasingly popular. Rather than covering multiple panels (like a conventional inverter), these are attached to each individual panel. It is now being recognised that these could be pivotal in accelerating the proliferation of photovoltaics. Though the initial cost of such systems is a little higher, they offer a number of advantages. These include greater degrees of scalability and the possibility of installing panels in different configurations without compromising overall system performance.
In addition, micro inverter systems do not require use of identical solar panels, so there is no restriction from a hardware perspective. This leaves plenty of scope to make amendments to the system where needed. And, as each photovoltaic panel is monitored individually, diagnostic functions can be applied. Changes to operational performance with age can thus be identified and faults dealt with.
Designers of photovoltaic inverters need to minimise power losses. Many of these losses relate to the switching losses of the constituent power transistors. The advent of wide bandgap semiconductor materials - such as gallium nitride (GaN) or silicon carbide (SiC) - has presented the industry with one potential way of enhancing system efficiency. However, the costs associated with transistors based on GaN or SiC are considerably higher than those of their Si-based equivalents. As a result, engineers are looking at how they can employ innovative circuit design to boost efficiency while keeping within budget. Advanced synchronous reverse blocking (A-SRB) is showing itself to be highly effective in this respect.
Toshiba has developed a series of A-SRB-related semiconductor solutions that can help designers improve inverter efficiency and reduce system size. For micro inverters with a maximum input power of 300W, for example, the company offers complete half-bridge, incorporating gate drivers with A-SRB functionality, switching transistors and SiC-based Schottky diodes.
To download a copy of our A-SRB whitepaper, click here: