To ensure the safe and reliable operation of a three-phase bridge leg, it is necessary to set a reasonable dead-time. Due to its own characteristics, the voltage variation in the dead-time of a gallium nitride high-electron mobility transistor (GaN HEMT) is different from those of traditional Si devices. In this paper, the problem of large reverse conduction voltage drops in GaN HEMT power devices is analyzed, and an improved online dead-time compensation method based on GaN HEMT power devices is proposed. This method can not only avoid the influence of circuit noise on the judgment of current direction, but also reduce the phase voltage error and current harmonics, thus improving the circuit stability. Finally, the effectiveness of the improved online dead-time compensation method was verified by simulation experiments and the construction of an experimental platform, indicating that it has obvious advantages over the traditional dead-time compensation method under the condition of large reverse conduction voltage drops.
| 科 Family | 属数 Number of genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) | 属 Genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) |
|---|---|---|---|---|---|---|
| 鹅膏菌科Amanitaceae | 2 | 11 | 5.26 | 鹅膏菌属 Amanita | 10 | 4.78 |
| 小菇科 Mycenaceae | 2 | 12 | 5.74 | 丝盖伞属 Inocybe | 5 | 2.39 |
| 多孔菌科 Polyporaceae | 8 | 14 | 6.70 | 蜡蘑属 Laccaria | 5 | 2.39 |
| 红菇科 Russulaceae | 3 | 23 | 11.00 | 小皮伞属 Marasmius | 6 | 2.87 |
| 小菇属 Mycena | 11 | 5.26 | ||||
| 光柄菇属 Pluteus | 5 | 2.39 | ||||
| 红菇属 Russula | 17 | 8.13 | ||||
| 栓菌属 Trametes | 5 | 2.39 |