Design And Research On Single-phase Two-stage PFC Switching Power Supply

Switching power supply is the wisdom of the power engineer and small, lightweight and high efficiency switching power converter is the constant pursuit of the goal. With the development, many of the traditional problems are resolved, but the switching power supply has its inherent problems, the power factor is relatively low. With the increasing of switching power converters and the increasing power of many devices, a large number of harmonic current is injected into power grid, seriously affecting the power quality and threaten the safe operation, and the same time increasing power consumption, reduce economic benefits. The face of harmonic current hazards, the International Electrochemical Commission (IEC) developed IEC 1000-3-2 standard, power factor correction (PFC) or reduce the harmonic currents made mandatory, the phenomenon forced the field of power electronics research staff to give this kind of problem effective solutions, thus the power factor correction technology of great significance and also is very necessary.Due to single-phase medium-power single-stage PFC converter switch voltage and current stress is relatively large, and the effect of power factor correction is far better than single-phase two-stage power factor correction. Therefore the research of single-phase two-stage power factor correction has practical significance and application value.Firstly paper introduces the significance of power factor correction and the development process, the power factor correction (PFC) of the principle is analyzed, and then on the power factor correction circuit topology, control methods were integrated and explained that today's technology research PFC Hot issue. In view of practical need, the mainly research of the APFC plus dual switch forward DC/DC converter single-phase two-stage PFC circuit is made, and a 100W double-loop control of test equipment is designed and developed. Paper introduces the design method of key circuit parameters in detail.Finally the test waveform is given.Our design and test results show that single-phase two-stage PFC converter has the following characteristics:low input current harmonic distortion and better output voltage characteristics, and conversion efficiency, power factor is relatively higher, and the consideration of electromagnetic interference, reliable operation. Basically the design performance indicators are meet. The power factor correction technology solutions have a certain practical application value.