Smaller inverters for offshore wind farms

Off-shore wind farms are a big deal in Europe. Germany’s Fraunhofer IZM – a well-known institute for applied research, development, and system integration of industrial electronics and semiconductor technology– devised a GaN-based inverter aimed at wind farm use. The small physical footprint made possible by wide bandgap power semiconductors really comes in handy for electronics that must sit at the top of a big steel tube in the middle of a sea somewhere. Meant as a technology demonstration, the Fraunhofer inverter has a high power density thanks to the smaller magnetics associated with the six GaN half-bridges. Gate signals are inductively coupled in, and gate control signals are accurate to within less than 500 psec so the amount of charge transferred to the FET gates can be set precisely, minimizing the chance of oscillations because of gate capacitance.
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