To address the problems of large current output harmonic, complex calculation and the need for additional setting of the neutral-point voltage weighting coefficient in conventional model predictive current control strategy for neutral point clamped three-level inverter, a variable extended space vector model predictive current control strategy is proposed. First, based on the deadbeat principle, the voltage vectors are optimized in the rotating 60° coordinate system; then, the duty ratio is dynamically changed according to the magnitude of the amplitude and phase errors between the reference voltage vector and the actual voltage vector, thus synthesizing a variable extended space vector set with reduced candidate voltage vector set to 8; subsequently, by constructing virtual vectors and introducing the neutral point balancing factor, the neutral point voltage weight coefficient is eliminated and has good neutral point voltage balancing ability; finally, the effectiveness of the proposed strategy is validated through experiments.
| 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 |