Ultrahigh Step-Up DC–DC Converter Composed of Two Stages Boost Converter, Coupled Inductor, and Multiplier Cell

In this paper, an ultrahigh step-up DC-DC converter is proposed with combination of a quadratic boost converter, a coupled inductor and a multiplier cell which doubles output voltage. Secondary side of the coupled inductor is unified with the multiplier cell. In addition, leakage energy of the coupled inductor is recycled and transferred to output perfectly which causes high efficiency performance. Main advantages of the converter include its high voltage gain, low voltage stress on its semiconductors and requiring smaller inductor in low voltage side of the converter. Power losses of the inductors are low due to current sharing between the input inductor and the coupled inductor. Continuity of input current and existence of a common ground between the load and source make the converter suitable for different applications. The converter is compared with the other converters based on analysis of its operation modes. Validity of the analysis and the converter performance are experimented using a 150W prototype that converters 20V from input side to 400V in output.