A 36-Pulse Diode-Bridge Rectifier Using Dual Passive Harmonic Reduction Methods at DC Link

In order to simultaneously reduce the harmonics of input line current and ripple of load voltage in multipulse diode-bridge rectifier, this paper proposes a 36-pulse rectifier using dual passive harmonic reduction methods at dc link. The proposed rectifier combines a 12-pulse rectifier and a multiwinding interphase reactor (IPR). The primary winding of the multiwinding IPR and two diodes constitute the double-tapped IPR, which is named as the first harmonic reduction method; the secondary winding of the multiwinding IPR and a single-phase diode-bridge rectifier formulate the second harmonic reduction method. When the multiwinding IPR is designed optimally, the pulse number of load voltage and step number of input line current can be increased from 12 to 24 by using the first method and from 24 to 36 by using the second method. The operation of the multiwinding IPR is analyzed, and the optimal turn ratio of the multiwinding IPR is obtained from the perspective of minimizing the total harmonic distortion of input line current. When the multiwinding IPR is designed optimally, both the pulse number of load voltage and step number of input line current are 36 per power supply cycle. Compared with the 12-pulse rectifier, in the proposed rectifier, the harmonics of input line current and ripple of load voltage are reduced significantly. The proposed rectifier is simpler and easier to realize than other methods. Some simulation and experiments are carried out to validate the theoretical analysis.