Design And Implementation Ofsingle-phase Active Power Factor Correction Circuit

With the rapid development of the power of science and technology, more and more switching power supplies and power electronic devices have been applied in our daily lives and production. The harmonic pollution of Grid is increasingly serious at the same time. In order to strengthen restrictions on harmonics, many domestic and foreign organizations and institutions make a strict harmonic standards. Active Power Factor Correction( Active Power Factor Correction, APFC) has excellent correction performance and stable control performance. It has become an important measures to suppress harmonics and improve power quality and efficiency. This article focuses on the research on active power factor correction(APFC) technology of the power supply,this research has important significance and practical value.This paper adopt average current control two-stage structure Active Power Factor Correction circuit, apply it to the research project 4kW Charger in the department, the purpose is to improve the power factor and efficiency of the system. The main research contents of this paper include: analyze and compare the work patterns and the control method of active power factor correction techniques, determine the control strategies and topologies. Establish mathematical model of the power factor correction stage and phase-shifted full-bridge DC/DC converter circuit in the subject, analyze the current loop and voltage loop of pre-stage, study and discuss the duty cycle loss phenomenon of phase-shifted full-bridge circuit and soft switching conditions in the switch. Secondly, the paper use professional circuit analysis software Matlab build simulation model for power factor correction stage, verify correctness and scientific of the control method and circuit topology which is used in this paper. In the end, we build a practical circuit structure, and apply it to the charging machine. Through the debugging and test of the system, the results show that the circuit which is designed in the issue has met the appropriate indicators in terms of performance and functionality.The single-phase Active Power Factor Correction circuit of this article can improve efficiency and power factor of system and reduce harmonic content,in addition, the circuit has the function of over-voltage protection and over-current protection and high temperature protection. Through testing on the system, the system has met the requirement in the function and met the indicator in the power factor, efficiency and the work temperature of the system. Apply it to 4kW charger, it can improve the efficiency and power factor. of the charger.