Analysis of high-frequency power conversion for series-connected universal link AC/DC power converter

This paper proposes a novel circuit topology for AC/DC power converter based on a high frequency universal link. And the operation principles of the circuit are presented. The proposed power converter has small capacitances at DC-links. The reactive components are minimized, and the circuit has advantage of the reduced volume and increased efficiency. Even though the voltage of the Is\´ DC-link is rectified version of input AC voltage and it is variable, the magnitude of series-connected output voltage is constant on the average sense thanks to so called "sine modulation". The demanded power is transferred by the phase-shift control between the series-connected sine-modulated voltage and the constant 2^nd DC-link voltage. The presented analysis derives the power transfer equation with high-frequency components and some experimental results show the validity of the analysis and the performance of the circuit.