Abstract: Provided is an integrated DC/DC and AC/DC converter system including a main relay selectively connected to any one of an AC power supply unit and a DC power supply unit and a controller connecting the main relay to the AC power supply unit or the DC power supply unit. Electrical energy based on the AC power output from the AC power supply and electrical energy based on DC power output from the DC power supply unit may be selectively provided to a load.

Abstract: Embodiments relate to a method and a device for switching media service channels, which minimize the time required to detect the first I frame for a switch channel by utilizing a caching server when switching channels in an IP-based media service, such as IPTV, and at the same time, minimize the time required for synchronization by changing time information in caching information transmitted from the caching server, such that channel switching between media service channels can be performed more quickly.

Abstract: A food freezing apparatus according to the present invention comprises: a transport unit having multiple vertically spaced levels provided so as to continuously transport food; a cooling unit for cooling the food transported by the multiple levels of the transport unit; a pre-freezing unit for pre-freezing the food transported by the multiple levels of the transport unit after having been cooled; a freezing unit for freezing the food transported by the multiple levels of the transport unit after having been pre-frozen; and a defrosting unit connected to the freezing unit so as to remove frost that forms inside the freezing unit.

Abstract: Provided is an integrated DC/DC and AC/DC converter system including a main relay selectively connected to any one of an AC power supply unit and a DC power supply unit and a controller connecting the main relay to the AC power supply unit or the DC power supply unit. Electrical energy based on the AC power output from the AC power supply and electrical energy based on DC power output from the DC power supply unit may be selectively provided to a load.

Abstract: According to various embodiments, a wireless power transmission device may comprise: a coil circuit configured to generate a power signal for power transmission to an electronic device; an inverter configured to convert direct current power to alternating current power and to provide the alternating current power to the coil circuit; a coil-type detection unit comprising a coil disposed to be adjacent to the coil circuit and configured to detect a signal corresponding to the power signal; and a control circuit configured to adjust, based on the detected signal, a switching frequency of the inverter to change the alternating current power output from the inverter.

Abstract: Disclosed is an asymmetrical half-bridge converter having high efficiency in a wide input voltage range. The converter may include a primary-side circuit including a first switch, a second switch, a primary-side capacitor, an additional inductor, and a primary-side magnetization inductor, and a secondary-side circuit including first and second diodes connected in series, first and second capacitors connected in series, a secondary-side rectification inductor having one end connected to the anode of the first diode and cathode of the second diode, and having the other end connected between the first and second capacitors connected in series, a first coupling inductor having one end connected to the cathode of the first diode and having the other end connected to the first capacitor, and a second coupling inductor having one end connected to the anode of the second diode and having the other end connected to the second capacitor.

Abstract: Disclosed are an electric vehicle capable of improving the charging efficiency of a charging apparatus by reducing the switching loss that may occur in the charging apparatus of an electric vehicle and a charging apparatus thereof. To this end, a power factor correction apparatus of an on board charger includes a first boost circuit receiving AC power through a first inductor to charge a load, a second boost circuit receiving the AC power through a second inductor to charge the load, and a third inductor provided between a leg of the first boost circuit and a leg of the second boost circuit so that parasitic capacitors of the first boost circuit and the second boost circuit are discharged.

Abstract: A discrete capacitance switching circuit includes a DC decoupling capacitor connected between a power node that receives an AC signal and a first node, a diode connected between the first node and a second node, a unit capacitor connected between the second node and a reference node that receives a ground voltage, and a bias circuit. The bias circuit is configured to apply a first DC voltage to the first node and apply a second DC voltage to the second node. The applied first and second DC voltages control a switching operation of the diode.

Abstract: Disclosed are a new phase shift full bridge (PSFB) converter using a clamp circuit connected to a center-tapped clamp circuit and an operating method thereof. The new PSFB converter using a clamp circuit connected to a center-tapped clamp circuit includes a primary-side circuit including a plurality of inductors connected to one end between a first switch and a second switch which are connected in series and to one end between a third switch and a fourth switch which are connected in series and a secondary-side circuit using a voltage applied by the primary-side circuit and including a clamping circuit configured with a first rectifier diode, a second rectifier diode, a third rectifier diode, a fourth rectifier diode, a first clamping diode, a second clamping diode and a capacitor in a center-tapped clamp circuit.

Abstract: Disclosed is an asymmetrical half-bridge converter having high efficiency in a wide input voltage range. The converter may include a primary-side circuit including a first switch, a second switch, a primary-side capacitor, an additional inductor, and a primary-side magnetization inductor, and a secondary-side circuit including first and second diodes connected in series, first and second capacitors connected in series, a secondary-side rectification inductor having one end connected to the anode of the first diode and cathode of the second diode, and having the other end connected between the first and second capacitors connected in series, a first coupling inductor having one end connected to the cathode of the first diode and having the other end connected to the first capacitor, and a second coupling inductor having one end connected to the anode of the second diode and having the other end connected to the second capacitor.

Abstract: Provided are a charge equalization apparatus for a battery string. According to the exemplary embodiments of the present invention, the charge equalization apparatus are modularized by being divided into the master unit and the slave unit, such that the charge equalization apparatus may be expanded and contracted independent of the number of batteries, the circuits are separated for each module, such that the circuits may be easily implemented, and when the circuits are damaged, only the damaged module is replaced, such that the effective countermeasure may be performed.

Abstract: Disclosed are a new phase shift full bridge (PSFB) converter using a clamp circuit connected to a center-tapped clamp circuit and an operating method thereof. The new PSFB converter using a clamp circuit connected to a center-tapped clamp circuit includes a primary-side circuit including a plurality of inductors connected to one end between a first switch and a second switch which are connected in series and to one end between a third switch and a fourth switch which are connected in series and a secondary-side circuit using a voltage applied by the primary-side circuit and including a clamping circuit configured with a first rectifier diode, a second rectifier diode, a third rectifier diode, a fourth rectifier diode, a first clamping diode, a second clamping diode and a capacitor in a center-tapped clamp circuit.

Abstract: Disclosed are an electric vehicle capable of improving the charging efficiency of a charging apparatus by reducing the switching loss that may occur in the charging apparatus of an electric vehicle and a charging apparatus thereof. To this end, a power factor correction apparatus of an on board charger includes a first boost circuit receiving AC power through a first inductor to charge a load, a second boost circuit receiving the AC power through a second inductor to charge the load, and a third inductor provided between a leg of the first boost circuit and a leg of the second boost circuit so that parasitic capacitors of the first boost circuit and the second boost circuit are discharged.

Abstract: A discrete capacitance switching circuit includes a DC decoupling capacitor connected between a power node that receives an AC signal and a first node, a diode connected between the first node and a second node, a unit capacitor connected between the second node and a reference node that receives a ground voltage, and a bias circuit. The bias circuit is configured to apply a first DC voltage to the first node and apply a second DC voltage to the second node. The applied first and second DC voltages control a switching operation of the diode.

Abstract: A method and an apparatus for controlling wireless power transmission are provided. An apparatus for controlling wireless power transmission includes a controller configured to determine an output voltage of a power factor correction unit based on charging information of a battery, the power factor correction unit configured to correct an input voltage into the determined output voltage, and output a variable voltage, and a resonance unit configured to transmit power converted from the variable voltage to a wireless power reception apparatus.

Abstract: The present invention relates to an electronic device and a method for controlling a charging operation of a battery. The charging control method includes charging a battery using a first charging mode, if a current voltage of the charged battery coincides with a predetermined voltage, decreasing an intensity level of a charging current and charging the battery using the decreased charging current intensity, and if the decreased charging current intensity coincides with a predetermined current intensity, converting from the first charging mode to a second charging mode and charging the battery using the second charging mode.

Abstract: A DC-DC converter includes: a clamp capacitor having one terminal connected with a ground terminal of a voltage source; a switching circuit including first and second switches connected with each other in series between a positive terminal and the ground terminal of the voltage source, and third and fourth switches connected with each other in series between both terminals of the clamp capacitor; and a forward-flyback transformer including a plurality of primary coils connected between a first connection node between the first and second switches and a second connection node between the third and fourth switches.

Abstract: Provided are a charge equalization apparatus for a battery string. According to the exemplary embodiments of the present invention, the charge equalization apparatus are modularized by being divided into the master unit and the slave unit, such that the charge equalization apparatus may be expanded and contracted independent of the number of batteries, the circuits are separated for each module, such that the circuits may be easily implemented, and when the circuits are damaged, only the damaged module is replaced, such that the effective countermeasure may be performed.

Abstract: A method and an apparatus for controlling wireless power transmission are provided. An apparatus for controlling wireless power transmission includes a controller configured to determine an output voltage of a power factor correction unit based on charging information of a battery, the power factor correction unit configured to correct an input voltage into the determined output voltage, and output a variable voltage, and a resonance unit configured to transmit power converted from the variable voltage to a wireless power reception apparatus.

Abstract: A method and an apparatus for controlling wireless power transmission are provided. An apparatus for controlling wireless power transmission includes a controller configured to determine an output voltage of a power factor correction unit based on charging information of a battery, the power factor correction unit configured to correct an input voltage into the determined output voltage, and output a variable voltage, and a resonance unit configured to transmit power converted from the variable voltage to a wireless power reception apparatus.