Analysis and Design of Isolated SEPIC Converter with Greinacher Voltage Multiplier Cell

  • Bernardo Andres Federal University of Santa Maria
  • Leonardo Romitti Federal University of Santa Maria
  • Fabrício Hoff Dupont Community University of Chapecó Region
  • Leandro Roggia Federal University of Santa Maria
  • Luciano Schuch Federal University of Santa Maria
Keywords: Isolated SEPIC, Resonant stage, Voltage multiplier cell


High step-up converters are required and used in photovoltaic applications, due to low voltage of photovoltaic modules. In this paper, an isolated dc-dc high step-up SEPIC with a Greinacher voltage doubler cell is presented. It has the advantage of continuous input current, high efficiency, high voltage gain, isolation and demands a single switch, being suitable for low power grid-tie photovoltaic systems. The operating principles and steady-state analysis are presented, including the detailed analysis of resonant stage, where the value of primary side capacitor is taken into account and plays an important role in the design of the converter, since it directly affects the resonance frequency and RMS current values. Simulation results are presented to validate the analysis and design.