Research on TCM Mode Control of a Signal-Phase Interleaved Inverter Based on GaN HEMTs

Gallium nitride (GaN) high electron mobility transistor (HEMT) has the advantage of high switching speed and low device loss, which makes it widely used in high-frequency applications. In order to solve a relevant and practical problem in the field of power electronics, namely, the trade-off between switching frequency, efficiency, and power density in single-phase inverters, the Triangle Current Mode (TCM) modulation is performed in this paper for the single-phase interleaved inverter based on GaN HEMTs. The full range zero voltage switching is realized by controlling the negative current and dead time, which achieves the purpose of high frequency, high efficiency and high power density. Additionally, the 220V/400VA prototype is constructed for verification. According to the experimental results, TCM modulation can achieve soft switching under different load conditions. When the maximum switching frequency can reach 590 kHz, the peak efficiency can reach 98.5% and the power density can reach 108 W/in3. The modulation strategy based on TCM shows great advantages in improving the overall efficiency and power density of the converter.