In this paper, the zero voltage switching (ZVS) region of a dual active bridge (DAB) converter with wide band-gap (WBG) power semiconductor device is analyzed. The ZVS region of a DAB converter varies depending on out...In this paper, the zero voltage switching (ZVS) region of a dual active bridge (DAB) converter with wide band-gap (WBG) power semiconductor device is analyzed. The ZVS region of a DAB converter varies depending on output power and voltage ratio. The DAB converters operate with hard switching at light loads, it is difficult to achieve high efficiency. Fortunately, WBG power semiconductor devices have excellent hard switching characteristics and can increase efficiency compared to silicon (Si) devices. In particular, WBG devices can achieve ZVS at low load currents due to their low parasitic output capacitance (C<sub>o,tr</sub>) characteristics. Therefore, in this paper, the ZVS operating resion is analyzed based on the characteristics of Si, silicon carbide (SiC) and gallium nitride (GaN). Power semiconductor devices. WBG devices with low C<sub>o,tr</sub> operate at ZVS at lower load currents compared to Si devices. To verify this, experiments are conducted and the results are analyzed using a 3 kW DAB converter. For Si devices, ZVS is achieved above 1.4 kW. For WBG devices, ZVS is achieved at 700 W. Due to the ZVS conditions depending on the switching device, the DAB converter using Si devices achieves a power conversion efficiency of 91% at 1.1 kW output. On the other hand, in the case of WBG devices, power conversion efficiency of more than 98% is achieved under 11 kW conditions. In conclusion, it is confirmed that the WBG device operates in ZVS at a lower load compared to the Si device, which is advantageous in increasing light load efficiency.展开更多
The radio-frequency (RF) performance of the p-type NiO-pocket based β-Ga_(2)O_(3)/black phosphorous heterostructureMOSFET has been evaluated. The key figure of merits (FOMs) for device performance evaluation include ...The radio-frequency (RF) performance of the p-type NiO-pocket based β-Ga_(2)O_(3)/black phosphorous heterostructureMOSFET has been evaluated. The key figure of merits (FOMs) for device performance evaluation include the transconductance(gm) gate dependent intrinsic-capacitances (Cgd and Cgs), cutoff frequency (fT), gain bandwidth (GBW) product and output-conductance(gd). Similarly, power-gain (Gp), power added efficiency (PAE), and output power (POUT) are also investigated for largesignalcontinuous-wave (CW) RF performance evaluation. The motive behind the study is to improve the β-Ga_(2)O_(3) MOS deviceperformance along with a reduction in power losses and device associated leakages. To show the applicability of the designeddevice in RF applications, its RF FOMs are analyzed. With the outline characteristics of the ultrathin black phosphorous layer belowthe β-Ga_(2)O_(3) channel region, the proposed device results in 1.09 times improvement in fT, with 0.7 times lower Cgs, and 3.27dB improved GP in comparison to the NiO-GO MOSFET. The results indicate that the designed NiO-GO/BP MOSFET has betterRF performance with improved power gain and low leakages.展开更多
文摘In this paper, the zero voltage switching (ZVS) region of a dual active bridge (DAB) converter with wide band-gap (WBG) power semiconductor device is analyzed. The ZVS region of a DAB converter varies depending on output power and voltage ratio. The DAB converters operate with hard switching at light loads, it is difficult to achieve high efficiency. Fortunately, WBG power semiconductor devices have excellent hard switching characteristics and can increase efficiency compared to silicon (Si) devices. In particular, WBG devices can achieve ZVS at low load currents due to their low parasitic output capacitance (C<sub>o,tr</sub>) characteristics. Therefore, in this paper, the ZVS operating resion is analyzed based on the characteristics of Si, silicon carbide (SiC) and gallium nitride (GaN). Power semiconductor devices. WBG devices with low C<sub>o,tr</sub> operate at ZVS at lower load currents compared to Si devices. To verify this, experiments are conducted and the results are analyzed using a 3 kW DAB converter. For Si devices, ZVS is achieved above 1.4 kW. For WBG devices, ZVS is achieved at 700 W. Due to the ZVS conditions depending on the switching device, the DAB converter using Si devices achieves a power conversion efficiency of 91% at 1.1 kW output. On the other hand, in the case of WBG devices, power conversion efficiency of more than 98% is achieved under 11 kW conditions. In conclusion, it is confirmed that the WBG device operates in ZVS at a lower load compared to the Si device, which is advantageous in increasing light load efficiency.
文摘The radio-frequency (RF) performance of the p-type NiO-pocket based β-Ga_(2)O_(3)/black phosphorous heterostructureMOSFET has been evaluated. The key figure of merits (FOMs) for device performance evaluation include the transconductance(gm) gate dependent intrinsic-capacitances (Cgd and Cgs), cutoff frequency (fT), gain bandwidth (GBW) product and output-conductance(gd). Similarly, power-gain (Gp), power added efficiency (PAE), and output power (POUT) are also investigated for largesignalcontinuous-wave (CW) RF performance evaluation. The motive behind the study is to improve the β-Ga_(2)O_(3) MOS deviceperformance along with a reduction in power losses and device associated leakages. To show the applicability of the designeddevice in RF applications, its RF FOMs are analyzed. With the outline characteristics of the ultrathin black phosphorous layer belowthe β-Ga_(2)O_(3) channel region, the proposed device results in 1.09 times improvement in fT, with 0.7 times lower Cgs, and 3.27dB improved GP in comparison to the NiO-GO MOSFET. The results indicate that the designed NiO-GO/BP MOSFET has betterRF performance with improved power gain and low leakages.
