Abstract:
Disclosed herein is an electric generating system using a solar cell which converts a voltage generated in the solar cell into an Alternating Current (AC) voltage, and applies the converted voltage to a power system. The electric generating system includes; a Direct Current (DC)/DC converter that converts the voltage generated in the solar cell into a DC voltage, and has a synchronous rectifier including a synchronous switch; and a controller that detects one of a phase and a voltage of the power system, and selectively connects the synchronous switch of the synchronous rectifier in accordance with one of the phase and voltage of the power system. Here, the electric generating system reduces a conduction loss, and increases overall efficiency of the electric generation system.
Abstract:
An electric generating system using a solar cell improves the quality of output power by including a converter for converting an output voltage generated from the solar cell into a DC voltage in a pulse shape. An inverter converts the DC voltage in the pulse shape into an AC voltage and applies the AC voltage to a power system and a control device for determining whether an erroneous operation of the electric generating system using the solar cell is generated or not based on an output voltage of the solar cell, an output current of the solar cell and a voltage of the power system. At least one inverter switching device among a plurality of inverter switching devices performs a switching at a frequency higher than a frequency during a normal operation at an interval where the erroneous operation is generated.
Abstract:
There are provided a method and an apparatus for generating a current command value for tracking the maximum power point of a solar energy generating system. The apparatus includes: a voltage detector detecting a voltage input into the flyback power converter; a first calculator calculating an output power from the detected input voltage; a second calculator calculating a power variation based on the calculated output power and a voltage variation of the input voltage; and a current command value generator generating a current command value for tracking the maximum power point of the solar cell module from the calculated voltage variation and the calculated power variation. Accordingly, a current command value after calculating an output power may be generated with only a voltage detector, without a current detector, thereby reducing the costs of a solar energy generating system by decreasing the costs for a high-priced current detector, and simplifying circuit.
Abstract:
The present invention provides a switching device and a method for preventing malfunction of the same. The switching device includes: a controller for outputting a plurality of digital control signals; a protecting unit connected to the controller for protecting all signals when the plurality of digital control signals outputted from the controller are simultaneously received at a state of ON; a gate driver connected to the protecting unit for generating a switch control signal by converting the control signal passed through the protecting unit; and a plurality of switches connected to the gate driver for individually performing ON•OFF operations according to each of the switching control signals.
Abstract:
A head lamp for a vehicle is provided, which includes a reflector for reflecting light emitted from a light source, a reflection plate for collecting the light reflected from the reflector in an upward direction, a micro-reflection module provided over the reflector to tilt and reflect the light collected by the reflection plate at a desired angle, and an optical lens for irradiating the light reflected from the micro-reflector onto a road surface. The head lamp can implement various beam patterns in accordance with road and surrounding circumferences, and irradiate vehicle information onto a road surface, thereby reducing the dazzle of other drivers of opposite vehicles and improving the field of vision of the driver to improve the safety and convenience.
Abstract:
The steam generator for a fuel cell with dual use for heating fuel electrode gas according to the invention is configured as a single unit comprising a steam generator (100) that heats introduced water to generate steam, a steam superheater (200) that is connected to the steam generator (100) and used to supply superheat to the steam in order to elevate the temperature of the steam, and a fuel electrode gas heater (300) that is used to supply heat to the fuel electrode gas in order to elevate the temperature of the fuel electrode gas. The steam generator (100), steam superheater (200) and fuel electrode gas heater (300) are connected with an air electrode exhaust gas flow path through which the air electrode exhaust gas passes, to receive heat supply through heat exchange.
Abstract:
A method of controlling an adjustable antenna of a digital television receiver including (a) storing an effective power of a channel signal received through the antenna in a memory by rotating the direction of the antenna and selecting an antenna pattern when a maximum signal power is detected (b) aligning the stored antenna patterns in order of sizes of the signal powers, and (c) detecting states of the channel signal, a power of the channel signal, a maximum ghost power, and a signal vs. noise ratio and then changing a pattern of the antenna in accordance with the detected states.
Abstract:
A stack fastening device includes a base, on an upper surface of which a stack is loaded, a compression plate, which has a flat configuration and is placed over the stack to press the stack, and a plurality of vertical beams, which are installed on the base to extend vertically so that the upper end portion of the beams projects out through the edge of the compression plate, A thread is formed in an upper end portion of each vertical beam, nuts are threadedly coupled to the thread such that the nuts can be tightened against upper and lower surfaces of the compression plate, and engagement grooves are defined in the upper surface of the compression plate so that a head of a hydraulic cylinder can be coupled to the compression plate.
Abstract:
Disclosed is a lamp assembly providing multiple beam patterns in accordance with traveling conditions of a vehicle. The lamp assembly includes a lamp, a lamp shield driving apparatus blocking a part of light from the lamp by a predetermined shield pattern, a lens condensing the blocked light forward, and a housing accommodating the lamp and the lamp shield driving apparatus. The lamp shield driving apparatus includes a first shield having a predetermined cut off pattern, a second shield overlapping with the first shield and having a different cut off pattern from the first shield, and a driving unit moving either the first shield or the second shield linearly. Two or more beam patterns are formed in accordance with the movement of any one of the shields while the first shield overlaps with the second shield.
Abstract:
A molten carbonate fuel cell, which is provided with an indirect internal steam reformer to efficiently control heat and simplify the system construction and has a simple structure to reduce production cost and efficiently controls heat to reduce operational cost and increase operational efficiency, is disclosed. The molten carbonate fuel cell of the present invention has a plurality of unit cells each including a porous matrix plate which is interposed between an anode plate and a cathode plate and is filled with an alkali carbonate electrolyte, the unit cells being stacked on top of another; at least one indirect internal steam reformer interposed between the stacked unit cells and reforming a fuel to hydrogen through a reforming reaction and supplying the hydrogen to the unit cells; a fuel manifold air-tightly installed at an inlet of both the indirect internal steam reformer and the unit cells and receiving a fuel supply pipe therein to supply the fuel to the indirect internal steam reformer; and a reformed fuel manifold air-tightly installed at an outlet of both the indirect internal steam reformer and the unit cells and supplying the hydrogen produced by the indirect internal steam reformer to the unit cells.