Aimed at the shortcomings of large size, susceptibility to damage and high cost associated with electrolytic capacitors in permanent magnet synchronous motor (PMSM) drive systems, an active damping control strategy for PMSM without electrolytic capacitors is proposed by incorporating an RD damping circuit. First, the relationship between the selection of the film capacitor on the DC-bus side and the grid-side input power is analyzed, and the dynamic equations for the DC-bus voltage and capacitance are derived. Then, an active damping power decoupling method based on d-axis repetitive control is put forward to enhance the grid-side current power factor. Meanwhile, a control strategy based on q-axis power transformation is introduced to improve the motor's dynamic negative-impedance characteristics. The RD damping circuit is utilized to simplify control commands and absorb the overshoot voltage. Finally, simulation and experimental results indicate that with the use of small-capacity film capacitors, the active damping control effectively reduces the current distortion and suppresses the torque ripple.
| 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 |