Research Of A Three-Phase Power Actor Correction Based On Single-Phase Active Power Factor Correction

At present the implementation of three-phase power factor correction is mostly based on digital technology. A simple way to obtain three-phase-to-dc rectification with high power factor is to use single-phase power-factor-correction circuits. Its difficulty lies in the coupling of the three phases, the use of a dc/dc converter with an isolation transformer after each PFC circuit can decouples the three units, but is expensive .This paper researches a three-phase power factor correction based on Single-phase Active Power Factor Correction. Using staggered PWM and improvement of single-phase topology virtually eliminated the interaction among three-phase Active Power Factor Correction(APFC)circuit.A low power isolation transformer plus rectifier bridge circuit is proposed to solve the problem of the voltage sampling signals and chips have no common ground.Application of the differential amplifier is to resolve the problem of the current sampling signals and chips have no common ground. Application of the transformer-isolated gate drive circuit is to resolve the problem of the PWM signal of the chips and the MOSFET have no common ground. The experimental results verify the theoretical correctness and feasibility.Plus carrier technology is proposed to solve the problem of staggered PWM technique can not be achieved between the two single-phase PFC chips because of their fixed carrier. The experimental results verify the theoretical correctness and feasibility.Through trial and testing, has been know the chip carrier signal amplitude range and carrier shapes. Using simulation methods designed a Staggered triangular. The experimental results verify the theoretical correctness and feasibility.A 30-watt three-phase PFC design example and 1000-watt three-phase PFC design example along with experimental results are shown, which confirm the theoretical forecasts.