At present, multi-level three-phase voltage source inverters are widely applied in high-voltage and high-power electronic equipment. To solve the problem of DC-side capacitor voltage imbalance during the operation of the traditional three-phase voltage source inverter, the inverter structure is optimized in this paper based on the space vector modulation switch DC power supply. The equivalent model of a multi-level three-phase voltage source inverter is established, the space vector modulation algorithm of the 60° coordinate is used to realize the space vector modulation, and the capacitor voltage balance algorithm is used to fully take into account the switching sequence between different vectors, thus realizing the capacitor current balance. Experimental results show that compared with the traditional method, the proposed method can modulate the multi-level three-phase voltage source inverter, the output line voltage waveform distortion rate is 0.18%, and the voltage fluctuation at the capacitor point can be controlled within 3 V, indicating that this method is superior to the comparison method and has a better application performance.
| 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 |