This article presents the first kW-Class, 3-phase GaN-based inverter. Hard-switched at 100-kHz PWM, its heart is a 6-in-1 power module with 600-V GaN power HEMTs, achieving a new efficiency of 98.5%, a more than 2% improvement.
[pdf] The high-frequency inverter first uses high-frequency DC/DC conversion technology to invert low-voltage direct current into high-frequency and low-voltage alternating current; then, after being boosted by a high-frequency transformer, it is rectified by a high-frequency rectifier filter circuit to usually above 300V High-voltage DC power; finally, 220V power frequency AC power is obtained through the power frequency inverter circuit for the load.
[pdf] 3-phase string inverters perform power conversion on series-connected photovoltaic panels. Usually, these inverters are rated around a few kilowatts up to 350 kW. In general, most inverter designs are transformerless or non-isolated. String inverters typically rely on two-stage power conversion.
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