一种基于改进双二极管脉波倍增电路的串联型 24 脉波整流器

A series-connected 24-pulse rectifier based on improved dual-diode pulse-doubling circuit (IDPC) is proposed in this paper to effectively suppress the input current harmonics of the rectifier without increasing the complexity of the phase-shifting transformer in the series-connected 12-pulse rectifier. The proposed IDPC is mounted on the DC side of the rectifier, and it consists of a single-phase autotransformer, an inter-phase reactor, two capacitors, and two auxiliary diodes. The auxiliary diodes in IDPC alternately conduct according to the relationship between the output voltage of the two three-phase bridge rectifiers in the rectifier and the voltage of the single-phase autotransformer windings. This enables the IDPC to work periodically in three modes, thereby increasing the pulse number of the rectifier from 12 to 24 according to the voltage and current relationship between the AC and DC sides. This increase in pulse number reduces the THD of the input current to half of the original one, effectively suppressing the input current harmonics. Since the total capacity of the magnetic devices in IDPC is only 2.35% of the output power and the current stress of the auxiliary diodes is only 6.8% of the output current, the proposed scheme has the advantages of simple circuit structure, small capacity, low cost and small conduction loss. Compared with similar structures, the proposed rectifier has better application prospects in medium-and high-voltage industrial applications. An experimental prototype with output power of 1 kW is built, and the experimental results verify the validity and correctness of the theoretical analysis..