The Dual Star Rectifier System Based On AIPR

Compared with the three-phase bridge circuit, dual star rectifier circuit rectifierhad only one tube’s voltage drop on its conduction path,which means the rectifiercircuit has smaller on-state losses.Therefore, dual star rectifier circuit has beenwidely used in electrolytic plating, electric heating, submerged arc welding andother low-voltage high-current, high-power occasions. However, as a strongnonlinear loads of grid, this rectifier circuit input current harmonic content is alsohigh. Therefore, this paper attempts to apply the harmonic suppression technologyof active interphase reactor to dual star rectifier circuit, and focuses on itseffectiveness, the mechanism of harmonic suppression as well as its circuitimplementation methods to carry out specific research.According to the result which the active interphase reactor (AIPR) technologyin the12-pulse rectifier systems have concluded, interphase reactor secondarywindings have the same phase of its voltage and current which means secondarywindings consume energy. In this paper, system pilot testing is conducted under theconditions of three output power ratings based on the analysis of the original dualstar rectifier system’s input current and output voltage. This paper found the law thatthe passive load changes affected AC input current harmonic suppression’s resultand confirmed that the active interphase reactor harmonic suppression technologyfor dual star rectifier circuit is feasible.The harmonic suppression mechanism of AIPR-based dual star rectificationsystem is researched. By switching function method, the system first analyzes theinput current and output voltage characteristics; Second, it analyzes the DC sidecirculating current waveforms required for circulation when the input currentharmonic is zero. Again, it analyzes the amplitude and phase of circulating currentwhen the rectification system input current has the least harmonics; Finally, theAIPR energy flow direction and its equivalent capacity is analyzed.According to the theoretical analysis of the actual circulating current whichneeds to meet the amplitude and phase condition,this paper designed the activeinterphase converter which transport the harmonic energy to the load side toimprove system efficiency. The active interphase converter is a single-phase PWMrectifying circuit essentially and its circuit is designed detailed which inconcludedthe main circuit topology and parameter design, control and drive circuits. Thispaper developed a900W AIPR-based dual star rectifier system and conductedexperiments to verify the theoretical analysis of harmonic suppression mechanismresults by analyzing experimental results. In the dual star rectifier system based on AIPR, the active interphase convertercan effectively inhibit the system’s harmonic content and its capacity is smallrelative to the system output the system power output. This paper through analysisedthe rectifier system’s harmonic suppression mechanism draw a conclusion that theAIPR technology for dual star rectifier system can significantly suppress harmonicswhile maintaining high system efficiency. It laid a solid technical foundation for theAIPR technology used in low voltage high current applications.