Abstract: There is provided a photovoltaic and fuel cell hybrid generation system using dual converters and a single inverter and a method of controlling the same. A photovoltaic and fuel cell (PV-FC) hybrid generation system according to an aspect of the invention may include: a PV DC/DC converter unit converting a PV output voltage into a predetermined voltage; an FC DC/DC converter unit converting an FC output voltage into a predetermined voltage; a DC link unit commonly connecting an output terminal of the PV DC/DC converter unit and an output terminal of the FC DC/DC converter unit, and linking the converted PV output voltage from the PV DC/DC converter unit to the converted FC output voltage from the FC DC/DC converter unit to thereby generate a DC voltage; and a DC/AC inverter unit converting the DC voltage from the DC link unit into a predetermined AC voltage.

Abstract: There are disclosed a photovoltaic and fuel cell (PV-FC) hybrid generation system using a single converter and a single inverter, and a method of controlling the same. The PV-FC hybrid generation system includes a DC/DC converter unit converting an FC output voltage from a fuel cell, converting chemical energy into electrical energy, into a preset voltage, a DC link unit commonly connecting an output terminal of a photovoltaic cell, converting the sunlight into electrical energy, and an output terminal of the DC/DC converter unit, and linking the converted FC output voltage from the DC/DC converter unit with a PV output voltage from the photovoltaic cell to thereby generate a DC voltage, and a DC/AC inverter unit converting the DC voltage from the DC link unit into a preset AC voltage. Furthermore, a method of controlling the PV-FC hybrid generation system is proposed.

Abstract: There is provided an integrated control method for eliminating a low frequency ripple in a power conversion system for a fuel cell, more particularly, a control method of a power conversion system capable of eliminating a low frequency ripple, controlling a DC link voltage, and controlling an output power and a system using the same control method. A power conversion system (PCS) that converts an output of a DC power supply received from an external power supply includes a converter that converts a voltage of the input power supply; an inverter that converts an output voltage of the converter into an AC voltage; and a converter control module that outputs a PWM signal for controlling a switch of the converter, and after receiving a power instruction value, the converter control module generates the PWM signal for controlling the converter based on the power instruction value.

Abstract: A method for selecting the optimum number of phases for a converter is provided, which selects a duty range using an input voltage and an output voltage, obtains ripple values for multiple phases in the duty range, and selects the optimum number of phases using the corresponding ripple values. The method for selecting the optimum number of phases for a converter includes a duty range selection step of selecting a duty range using an input voltage and an output voltage, a ripple value calculation step of obtaining ripple values for multiple phases within the selected duty range, a range ripple selection step of selecting one or more phases in the duty range, and a rated ripple selection step of selecting the phases having the minimum ripple value in a rated duty among the phases selected in the range ripple selection step.