Research On Step-up And Step-down 12-pulse Auto-transformer Rectifier Unit And Monitoring Technology

With the development of multi-electric/electric aircraft,the demand for electric power of airborne equipment is increasing,and the aviation high voltage DC system will also be more applied in the aircraft power system.The multi-pulse auto-transformer rectifier generates some three phase voltage with a certain phase shift angle which across the rectifier circuit to output DC voltage.When the input current is synthesized,some specific frequency current harmonic content can be offset and the total harmonic distortion can be reduced which improves the quality of the electric energy.At present,most ATRU structures are difficult to regulate,unable to get wide range and continuous output DC voltage,so it needs a further study about the regulation method.Also,whether the power system can work normally has a significant influence on aviation safety.Therefore,the detection control and protection device is an important part of the aircraft power system.When obtaining the detected signal,the control device mainly inputs the fault signal into the control device according to the power supply mode and the logical relationship through comprehensive comparison,so that the fault part is separated from the whole power supply system,so as to ensure the safe and reliable power supply.This paper first study on the existing topology of 12 pulse ATRU.In order to suit more voltage levels and achieve continuous regulation of output voltage,this paper focuses on the study of step-up and step-down 12 pulse ATRU.The voltage regulation of output voltage is realized by reasonably designing the positions of middle taps and the number of windings.Then,the relationship between the ratio of auto-transformer input and output voltage,number of auto-transformer winding,system current and kilovoltampere rating are studied.Also analyzes the influence winding structure and kilovoltampere rating under different voltage ratio.The monitoring circuit is designed to monitor some input and output parameters,prevent the situations such as over/under voltage and overcurrent,so as to ensure the normal operation of the system.Finally,the simulation research is carried out by Saber simulation software,an ATRU prototype and a monitoring PCB circuit are designed,the rationality of the corresponding design and topology is verified by the experiment.