Abstract: There is provided a planar transformer having a dual-bobbin structure. The planar transformer includes a core unit including a pair of cores that are electromagnetically coupled to each other, and a bobbin unit including an inner bobbin part and a board part. The inner bobbin part includes a bobbin body having a predetermined volume and having a through hole into which the core is inserted, and a first winding wound around an outer circumferential surface of the bobbin body, and the board part includes at least one board including a board body having a predetermined surface area and having a through hole into which the inner bobbin part and the core are inserted, and a second winding formed on at least one surface of the board body and causing electromagnetic action with the first winding.

Abstract: A power supply having improved system efficiency includes: a standby stage converting a DC voltage into an operating voltage and a first standby voltage, which have a preset magnitude, and supplying the first standby voltage to a standby output terminal; a DC/DC stage supplied with the operating voltage from the standby stage, converting the DC voltage into a main voltage having a preset magnitude, and supplying the main voltage to a main output terminal; and a main/standby stage converting the main voltage from the DC/DC stage into a second standby voltage having a preset magnitude, and supplying the second standby voltage to the standby output terminal.

Abstract: A load sharing device for load balancing among a plurality of power supply modules connected in parallel to a single load includes a common voltage control signal output unit and output voltage control units corresponding to the power supply modules, respectively. The common voltage control signal output unit generates a common voltage control signal from output voltages of the power supply modules and outputs the common voltage control signal to the power supply modules. The output voltage control units detect output currents of the power supply modules and control the output voltages of the power supply modules to be in a predetermined voltage range according to the common voltage control signal and the detected output currents.

Abstract: The present invention relates to a charge equalization apparatus, in which series-connected batteries are divided into modules having certain sizes, and intra-module charge equalization and inter-module charge equalization are simultaneously performed, thus improving charge equalization performance and reducing the circuit size.

Abstract: A phase shift full bridge converter with a reduced current stress includes: a switching unit that switches an input voltage; a transformer that includes a first capacitor serially connected to, and having a primary side and a secondary side; an auxiliary circuit unit that includes a first switch, a second switch, and a second capacitor, which are connected in parallel to the secondary side of the transformer; and a rectification unit that is connected to the auxiliary circuit unit, with an output inductor being removed.

Abstract: A direct current (DC) power supply for varying an output voltage according to a load current variation is disclosed. The DC power supply includes an alternating current (AC)/DC conversion unit converting commercial AC power into DC power, a DC/DC conversion unit converting a voltage level of the DC power and outputting output power, and a control unit controlling conversion of the voltage level of the fed-back DC power according to a variation in a load current of the output power from the DC/DC conversion unit.

Abstract: The present invention relates to a charge equalization apparatus, which can enable the primary windings and the secondary windings of transformers to be easily manufactured, can control the flow of charges into batteries depending on the charged states of series-connected batteries, and can prevent overcurrent from flowing into batteries that are currently being charged.

Abstract: The present invention relates to a charge equalization apparatus, which allows the primary and secondary windings of a transformer to be easily fabricated, can control the flow of charge to batteries depending on the charged states of series-connected batteries, and can prevent overcurrent from flowing into a battery currently being charged.

Abstract: The present invention relates to a charge equalization apparatus, which allows the primary and secondary windings of a transformer to be easily fabricated, can control the flow of charge to batteries depending on the charged states of series-connected batteries, and can prevent overcurrent from flowing into a battery currently being charged.

Abstract: The present invention relates, in general, to a charge equalization apparatus with series-connected battery cells and, more particularly, to a charge equalization apparatus, in which series-connected battery cells (B1 to BN) are connected in parallel with the primary windings (Mi 1 to M1N) of transformers (T1 to TN), switches (S1 to SN) for controlling the flow of current of the primary windings are connected in series with the primary windings (M1 1 to M1N), and multiple secondary windings (M21 to M2N) corresponding to the primary windings are connected in parallel with each other.

Abstract: There is provided a planar transformer having a dual-bobbin structure. The planar transformer includes a core unit including a pair of cores that are electromagnetically coupled to each other, and a bobbin unit including an inner bobbin part and a board part. The inner bobbin part includes a bobbin body having a predetermined volume and having a through hole into which the core is inserted, and a first winding wound around an outer circumferential surface of the bobbin body, and the board part includes at least one board including a board body having a predetermined surface area and having a through hole into which the inner bobbin part and the core are inserted, and a second winding formed on at least one surface of the board body and causing electromagnetic action with the first winding.

Abstract: The present invention relates to a user-participating type fitness lecture system and a fitness training method using the same. More specifically, the present invention relates to a user-participating type fitness lecture system that provides direction for correcting a user's posture or motion by comparing the user's motions with user created contents (UCC). When the contents are played back for the user to emulate, correctness of the user's motion is grasped by detecting and comparing motions in the contents with the user's motion photographed through a camera, and providing the user with posture correction information in image or voice formats.

Abstract: There is provided a transformer improved in leakage inductance including: a core having first, second and third legs electromagnetically coupled to one another; a primary winding formed of a conductor having one end and another end receiving power from the outside and dividedly wound around the first, second and third legs; and a secondary winding wound around at least one of the first, second and third legs and receiving induced power by electromagnetic induction with the primary winding.

Abstract: The present invention relates to a charge equalization apparatus, which allows the primary and secondary windings of a transformer to be easily fabricated, can control the flow of charge to batteries depending on the charged states of series-connected batteries, and can prevent overcurrent from flowing into a battery currently being charged.

Abstract: The present invention relates to a load sharing device and a parallel power supply therewith. There is provided a parallel power supply, including: a plurality of power supply modules each connected to a single load in parallel to provide balanced output currents to the single load; a common voltage control signal output unit that generates a common voltage control signal from output voltages of the plurality of power supply modules and outputs the common voltage control signals to the plurality of power supply modules; and output voltage control units that are provided in the respective plurality of power supply modules to detect output currents of the plurality of power supply modules and to control output voltages of the plurality of power supply modules according to the detected signals, controlling the output voltages to be in a predetermined voltage range according to the common voltage control signals.

Abstract: The present invention relates, in general, to a charge equalization apparatus for batteries and, more particularly, to a charge equalization apparatus, in which the primary windings (M11 to M1N) of a number of transformers (T1 to TN) corresponding to the number of battery cells are connected in parallel with each other, a switch (S) for controlling the flow of current of the primary windings (M11 to M1N) of the parallel-connected transformers is connected in series with the parallel-connected primary windings, respective secondary windings (M21 to M2N) corresponding to the primary windings are connected in parallel with the battery cells, and the battery cells are connected in series with each other.

Abstract: The present invention provides a power supply for a server including: a PFC (Power Factor Correction) unit for meeting harmonic regulation by being connected to an input power source; a DC/DC unit including a switching stage provided with at least one switching device to switch a voltage of a link capacitor as an output voltage of the PFC unit to a predetermined operation frequency and a DC/DC stage driven by the switching stage; a DC/DC control unit for controlling the DC/DC unit by being connected to the switching device; and a frequency varying circuit unit for supplying the DC/DC control unit with a frequency control signal to adjust the operation frequency of the switching device according to load after detecting an output current of the link capacitor and acquiring load information.

Abstract: The present invention relates to an automatic charge equalization apparatus and method having an automatic PWM generating means for a series-connected battery string. The automatic charge equalization method and apparatus for a series-connected battery string according to the present invention can improve charge equalization by accomplishing charge equalization operation after comparing the potential of the corresponding battery cell with the average potential of the plurality of battery cells including the corresponding battery cell upon charging or discharging the corresponding battery cell.

Abstract: The present invention relates to a charge equalization apparatus, in which series-connected batteries are divided into modules having certain sizes, and intra-module charge equalization and inter-module charge equalization are simultaneously performed, thus improving charge equalization performance and reducing the circuit size.

Abstract: A soft start circuit is connected to a pulse width modulation controller including an oscillator, and a functionality of modulating amplitude to a pulse width and a power supply includes the soft start circuit. The soft start circuit includes a frequency controlling unit, a duty ratio establishing unit, and a variable switching unit. The frequency controlling unit generates first and second parameter signals for determining a frequency signal frequency by a power source from the PWM controller and provides them to the PWM controller. The duty ratio establishing unit generates a third parameter for determining amplitude of the frequency signal generated by the PWM controller according to a reference voltage, and provides it to the PWM controller. The variable switching unit determines whether it is a first predetermined time from a start-up state, and controls the first parameter of the frequency controller during the first predetermined time.