In response to the high-voltage steep pulse application demands such as those in the biomedical industry, a series and parallel high-voltage steep pulse generator circuit based on solid-state switches is designed, and a novel pulse steepening method is proposed by combining the timing control technology. The key to pulse steepening, the system's working process and the main points of design are analyzed theoretically. This method can better reduce the influences of stray parameters, wiring inductance and wire inductance on the switching speed after adding the switching tubes. An experiment was carried out with a 2 kV high-voltage DC power supply and a load resistance of 110 Ω, and experimental results show that the rising edge of load pulse signal was 50 ns approximately, the falling edge was 70 ns approximately, and the output current amplitude was 18 A approximately. The half-height width of the minimum pulse width signal was 100 ns, and the system's minimum resolution was 5 ns, which can realize a flexible adjustment of 5 ns pulse width step by step. The maximum pulse width was related to the energy storage capacitor.
| 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 |