Abstract:
저전압 대전류 출력특성을 갖는 배터리 또는 수퍼캐패시터와 같은 에너지저장장치의 충전과 방전 제어를 할 수 있는 고효율의 전력변환기술을 제공하고자 한다. 본 발명의 일 실시예에 따른 다상 인터리브 양방향 DC―DC 컨버터는 전원과 전원의 입력전류를 저장하는 제1 입력 인덕터를 포함하는 입력부와, 제1 입력 인덕터와 연결되어 제1 입력 인덕터 전류를 제어하는 1차측 제1 하프브릿지와, 출력전압을 저장하는 출력부와, 출력부와 연결되어 출력전압을 제어하는 2차측 제1 하프브릿지와, 1차측이 1차측 제1 하프브릿지와 연결되고, 2차측이 2차측 제1 하프브릿지와 연결되되 전력모드에 따라 1차측 또는 2차측의 전압을 변압하는 제1 변압기를 포함하는 제1 양방향 DC-DC 컨버터와 제n 양방향 DC-DC 컨버터를 하나 이상 포함한다.
Abstract:
PURPOSE: A multiphase interleaved bidirectional DC-DC converter having a high boosting ratio is provided to implement the high efficient DC-DC converter by minimizing the conduction loss of each element through a paralleled mode. CONSTITUTION: A first input and output unit(110) includes a power element(111) and a plurality of inductors(112). A first half bridge(120) controls the voltage from the first input and output unit. A second input and output unit(130) inputs or outputs a single voltage. A second half bridge(140) controls the voltage from the second input and output unit. The second half bridge is connected between the second input and output unit and a transformer(150). [Reference numerals] (AA) Power flow; (BB) Primary side; (CC) Secondary side
Abstract:
PURPOSE: A synchronous buck converter distributing a current using input voltage difference and a current distributing method using the same are provided to prevent the heating of a device by reducing the difference of current amount distributed to the buck converter connected in parallel. CONSTITUTION: An input unit(100) supplies an input current(Iin) and an input voltage(Vin). A first converter(110) includes a first current generator(110a), a first PWM controller(110b) and a first sensor(110c). A second converter(120) includes a second current generator(120a), a second PWM controller(120b) and a second sensor(120c). A current difference detector(130) compensates a reference current by detecting the ripple difference of the input voltage. A frequency signal generating circuit(140) generates a frequency signal having a constant frequency. [Reference numerals] (100) Input unit; (100a) First current generator; (100b) First PWM controller; (100c) First sensing unit; (120a) Second current generator; (120b) Second PWM controller; (120c) Second sensor; (130) Current difference detector; (140) Frequency signal generating circuit
Abstract:
PURPOSE: A synthetic method of tubes consisting of nano-wire- microfiber hybrid structures and a tube structure manufactured by the same are provided to grow nano-wire by using a CVD method. CONSTITUTION: A synthetic method of tubes consisting of nano-wire- microfiber hybrid structures comprises the following steps: contacting microfiber wet by distilled water with wire surface of micro or macro scale; rotating the wire in the micro or macro scaled tubular structure; separating tubular structure microfiber layer from the micro fiber-wire complex and drying thereof; locating the dried tubular microfiber layer inside a reactor and removing impurities inside the reactor by lowering vacuum of the reactor; increasing the synthetic temperature of nano-wire while injecting the carrier gas into the reactor; providing the reaction gas which becomes the source of carbon and phosphorus and reacting the reaction gas with the tubular microfiber layer; and cooling the reactor down to the room temperature.
Abstract:
PURPOSE: A mass-synthesizing method of carbon nanotube and a carbon nanotube manufactured by using the method are provided to enhance carbon crystalline of the carbon nanotube and easily eliminate core material. CONSTITUTION: A mass-synthesizing method of a high purity carbon nanotube comprises next steps: putting metal oxide compound into a reactor; eliminating remnant oxygen within the reactor by lowering degree of vacuum; increasing inner temperature of the reactor while injecting carrier gas into the reactor; injecting hydrocarbon gas into the reactor; reacting the hydrocarbon gas with the metal oxide compound in order to manufacturing the heterogeneous nanowire which consists of inter metallic compound or alloy core; and heat treating the heterogeneous nanowire under hydrogen atmosphere. The metal oxide compound is a mixture of tin oxide and indium oxide. A mixing ratio of the tin oxide to the indium oxide is 6:1-1:6 in weight ratio. The reaction with the metal oxide compound with the hydrocarbon gas is processed at 550-850 deg Celsius and lasts within 2 hours.
Abstract:
PURPOSE: An HID(High Intensity Discharge) lamp driving circuit is provided to secure stable driving of the HID lamp by preventing an overvoltage after ignition of the HID lamp. CONSTITUTION: A power supply unit(1) rectifies AC power to DC power. An inverter(2) converts the DC power to the driving power of the lamp according to a switching driving signal. A control value generator(4) outputs a driving control signal for controlling a switching driving signal. An error amplifier(5) outputs the voltage in proportion to the difference between the output of the control value generator and the current transformer. A start frequency setting circuit(9) controls an initial voltage applied to the lamp. A voltage controlled oscillator(6) outputs the frequency corresponding to the output voltage of the start frequency set circuit and the output voltage of an error amplifier.
Abstract:
A magnetism inhalation valve of uniflow meso-scale microengine and functioning method for the same is provided to improve heating efficiency and endurance and simplify the whole configuration. A magnetism inhalation valve of uniflow meso-scale microengine comprises a cylinder block head(10), a cylinder head(20) layered on one side of the cylinder block head; and a cylinder sleeve(50) directing a piston(40) to move left and right. The fuel and the air carried from the fuel tank are mixed. The air-fuel mixture enters into the cylinder block head. The cylinder head ignites air-fuel mixture using a heater coil(21).
Abstract:
A method for fabricating an LED lamp is provided to improve a heat radiation characteristic as compared with a conventional high-output LED by directly radiating the heat generated by the light emitted from an LED through a substrate. An insulation layer is coated on the upper surface of a substrate(2), made of a predetermined pattern by an etch process. A metal layer is coated on the upper surface of the substrate by an etch process, having an electrode pattern(23) including a groove part on which an LED chip(3) is placed. The LED chip is directly inserted into the upper surface of the substrate through the groove part of the metal layer, connected to the electrode pattern by a wire. A reflection body(4) is inserted into the circumference of the LED chip connected to the electrode pattern wherein the upper part of the reflection body is broad and the lower part of the reflection body is narrow, having a through hole in its center to reflect the light emitted from the LED chip to the front area so that the lower part of the reflection body is open. A molding part(5) is molded by transparent resin to cover the LED chip, the electrode pattern and the reflection body. The metal layer can be made of copper.
Abstract:
A luminaire with a particular auto illumination control function is provided to reduce power consumption and be semi-permanently used by using a lighting composed of a plurality of light emitting diodes. A luminaire with a particular auto illumination control function includes a body(1), a plate(12), a plurality of light emitting diodes(121), a controller(14), and a power supply unit. The body is provided with an electrode unit(11) which is attachable to and detachable from one side or both sides. The plate is provided in a lower part of the body. The light emitting diodes is emitted by power supplied through the electrode unit. The controller is provided in the body and controls lighting of the light emitting diodes according to a sensed signal. The power supply unit converts and supplies the power supplied through the electrode unit to constituent components.
Abstract:
A module type hydrogen reformer is provided to maximize thermal efficiency of the system by direct use of heat generated by catalytic combustion or by supplying heat in a short distance within the reformer and to minimize the size of the hydrogen reformer at the same heat rate. A hydrogen reformer extracting hydrogen gas includes an exothermic device(1) for supplying a mixture of air and fuel for exothermic reaction of catalyst, an endothermic device(3) for supplying a gas mixture for endothermic reaction of catalyst to reform hydrogen, and a device(2) for generating both exothermic reaction as a secondary reaction and endothermic reaction as a primary reaction of hydrogen reforming by utilizing gas mixtures supplied from both the exothermic and endothermic devices.