Abstract: The present invention provides an LED driving circuit including: an inverter unit for switching an input power source; a plurality of transformers including a plurality of primary windings connected to the inverter unit and connected to each other in series and a plurality of secondary windings each of which is coupled with each of the primary windings; a plurality of rectification units each of which is connected to each of the secondary windings; and a plurality of LEDs each of which is connected to each of the rectification units.

Abstract: In accordance with the present invention, a power converter transformer for suppressing conduction EMI(ElectroMagnetic Interference) includes a primary winding positioned at a primary side; a secondary winding positioned at a second side and coupled with the primary winding; a parasitic capacitor connected between one end of the primary winding and one end of the secondary winding; a switching unit connected to the other end of the primary winding; a Y-capacitor connected between the switching unit and a ground terminal; an auxiliary winding positioned at the secondary side and coupled with the secondary winding; and an auxiliary capacitor connected between the one end of the primary winding and the auxiliary winding.

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 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: Provided is a power supply device including a power supply unit that supplies a driving voltage for driving at least one or more loads; a current balancing unit that maintains a current balance of the driving voltage supplied to the respective loads; a detection unit that detects currents flowing in the current balancing unit through electromagnetic induction so as to output a detection signal; and a control unit that receives the detection signal to judge whether the loads are opened or not and outputs a control signal for controlling the magnitude of the driving voltage.

Abstract: There is provided a variable switching frequency type power supply that can achieve high efficiency by fixing a switching duty cycle to 50% and varying switching frequency. A variable switching frequency type power supply according to an aspect of the invention may include: a switching unit switching input power; a transformation unit converting a voltage level of the power switched by the switching unit into a predetermined voltage level; a rectification unit rectifying the power converted by the transformation unit; and a control unit fixing a switching duty cycle of the switching unit to a predetermined switching duty cycle, and varying switching frequency of the switching unit according to a voltage level of output power.

Abstract: In accordance with the present invention, the SMPS circuit for PDP includes first and second transformers inducing voltages supplied to primary sides to secondary sides; a plurality of DC/DC converters connected to secondary sides of the first and second transformers and supplying voltages of different sizes; a clamp circuit connected to the secondary side of the first transformer and outputting an address voltage of a predetermined size by receiving a voltage supplied from the first transformer; and a linear regulator unit connected to the DC/DC converter for supplying a low voltage among the DC/DC converters connected to the secondary side of the first transformer and outputting a gate voltage of a predetermined size by receiving the low voltage supplied from the DC/DC converter.

Abstract: The present invention relates to power supplies, and more particularly, to a power supply having a maximum power point tracking function that can reduce manufacturing costs and circuit size by using a maximum power point tracking section with a simplified circuit in a solar photovoltaic power generator supplying power using sunlight instead of using a micro controller, the maximum power point tracking section that controls power switching according to a result of integration of a value obtained by dividing a power variation by a voltage variation to track a maximum power value.

Abstract: The present invention relates to power supplies, and more particularly, to a power supply having a maximum power point tracking function that controls power switching so that a detected power value is within a reference range having a maximum power point in a predetermined current-voltage curve. A power supply having a maximum power point tracking function according to an aspect of the invention includes: a converter section switching input power and converting the switched input power into predetermined DC power; and a maximum power point tracking section detecting a power value determined according to a switching operation of the converter section among power values included in a predetermined power-voltage curve, and controlling the switching operation of the converter section so that the detected power value is located within a predetermined reference range having a maximum power value among the power values included in the power-voltage curve.

Abstract: There is provided a high voltage power supply capable of reducing voltage stress of a voltage multiplying device. The high voltage power supply includes: a power converter switching on/off and converting an input direct current power into a direct current power having a preset voltage level; and a voltage multiplier including a first multiplying cell multiplying the voltage level of the direct current power from the power converter, wherein the first multiplying cell includes: first and second capacitors charging the direct current power from the power converter, respectively; a first diode providing a path for transferring the direct current power when the power converter is switched off; and a second diode providing a path for transferring the direct current power when the power converter is switched on.

Abstract: There are provided an integrated transformer in which a power conversion transformer and an inductor for stabilizing output power by the transformer are integrated into one transformer structure, and a power supply using the same. An integrated transformer according to an aspect of the invention includes: a core part including: first and second supports; and first and second outer legs and a center leg provided between the first and second supports, and magnetically connecting the first and second supports to each other, wherein a cross-section of the first and second outer legs and a cross-section of the center leg have a width of the first support and a width of the second support in a longitudinal direction, respectively, and a width of each of the first and second outer legs exceeds 0.5 times a width of the center leg but does not exceed 2 times the width of the center leg.

Abstract: Provided is a power supply device including a power supply unit that supplies a driving voltage for driving at least one or more loads; a current balancing unit that maintains a current balance of the driving voltage supplied to the respective loads; a detection unit that detects currents flowing in the current balancing unit through electromagnetic induction so as to output a detection signal; and a control unit that receives the detection signal to judge whether the loads are opened or not and outputs a control signal for controlling the magnitude of the driving voltage.

Abstract: The present invention is to provide a constellation search apparatus, method, and program, and a computer-readable storage medium storing the constellation search program, which can search for the constellations for a direction desired by a user, at any time, anywhere, and in any environment, and can quickly provide various pieces of information about the constellations that are found. The constellation search apparatus includes a database for storing information about locations of a plurality of constellations; a constellation search means comprising a reception unit for receiving azimuth and altitude values for a direction indicated by a 3-dimensional direction measurement means; a constellation search unit for searching for constellations located at the azimuth and altitude values, which are received by the reception unit, based on the constellation location information stored in the database; and an output unit for outputting search results found by the constellation search unit.