As a typical isolation topology, the push-pull converter has been widely applied in high-reliability scenarios because the transformer is bidirectionally magnetized and the input does not have the risk of bridge arm straight through. With an increase in the converter's operating frequency, the influence of common-mode interference becomes obvious. Therefore, the common-mode noise modeling analysis of the converter has important theoretical and application value for its electromagnetic compatibility optimization design. For a four-winding transformer with a central tap on both the primary and secondary sides, its two-capacitance parasitic parameter model is established in this paper. On this basis, a common-mode noise model in the frequency domain of the push-pull converter is established. Through the analysis of the common-mode noise source and the conduction path of common-mode noise, the prediction of common-mode noise is realized. To enhance the practicability of the model, the extraction method for parasitic capacitance parameters of the transformer is discussed for the simplified transformer model, and a common-mode noise suppression method based on a balancing capacitor is proposed. The accuracy of the established common-mode noise model and the effectiveness of the common-mode noise suppression method were verified by experimental results.
| 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 |