828results about How to "Improve power conversion efficiency" patented technology

Provided is a current-source push-pull DC-DC converter using an active clamp circuit for reusing energy of leakage inductances by not only diodes on a secondary side of a transformer being zero-current switched using a series-resonant full-wave rectifier, but also the active clamp circuit on a primary side of the transformer, which provides a discharge path of the energy stored in the leakage inductances, increases power conversion efficiency even for a wide input voltage range and reduces a switch voltage stress as compared to a conventional current-source push-pull circuit by operating even for a duty ratio below 0.5 by flowing a current of an input inductor through capacitors of the active clamp circuit when both main switches are off.

A current resonant DC-DC converter of multi-output type is provided which comprises an output-regulatory MOS-FET 40 connected between a secondary winding 5c of a transformer 5 and a smoothing capacitor 16 in a second rectifying smoother 17, and an output control circuit 41 for controlling the on-off operation of output-regulatory MOS-FET 40 based on voltage VO2 from smoothing capacitor 16 in second rectifying smoother 17. By turning the on-off operation of output-regulatory MOS-FET 40 in synchronization with switching frequency of first or second MOS-FETs 1, 2, an ideal cross regulation among respective DC outputs can be obtained, providing the inexpensive converter with simple circuit alteration capable of producing highly stable DC outputs with high power conversion efficiency, high accuracy and less power conversion loss.

A switching power supply device has a boost power converter which converts a wide range of AC input voltages into a DC voltage larger than an amplitude of the AC input voltage to supply to a DC-DC converter. The switching power supply device includes a load detection circuit, an input voltage detection circuit, and a power conversion controller for the boost power converter. The power conversion controller corrects the determination reference value in accordance with the AC input voltage detected in the input voltage detection circuit. When a light load is detected based on a comparison between the corrected determination reference value and the detection value output from the load detection circuit, the controller disables the boost power converter.

An encapsulant material with enhanced light reflectivity, a crystalline silicon photovoltaic module and a thin film photovoltaic module are provided. The encapsulant material has a porous structure therein, and an average pore diameter of the porous structure is between several hundreds of nanometers and several hundreds of micrometers, so that the light reflectance of the encapsulant material is improved. Moreover, the encapsulant material is crosslinked by a physical or chemical crosslinking method, so heat resistance thereof is improved. Therefore, the encapsulant material is suitable for the crystalline silicon photovoltaic module and the thin film photovoltaic module, so as to increase power conversion efficiency of these modules.

A multi-phase power source device capable of easily changing the number of phases is realized. For example, a plurality of drive units POL[1]-POL[4] corresponding to the number of phases are provided, wherein each POL[n] receives a phase input signal PHI[n] serving as a pulse signal, and generates a phase output signal PHO[n] by delaying PHI[n] by a predetermined cycles of a clock signal CLK. PHI[n] and PHO[n] of each POL[n] are coupled in a ring, wherein each POL[n] performs a switching operation with PHI[n] or PHO[n] as a starting point. In this case, each POL[n] charges and discharges a capacitor Cct commonly coupled to each POL[n] with an equal current, and a frequency of CLK is determined based on this charge and discharge rate. That is, if the number of phases increases n times, the frequency of CLK will be automatically controlled to n times.

The present invention is an organic light emitting device (OLED) comprising an anode, a cathode and a luminescent region provided between the anode and the cathode. The luminescent region comprises an electron injection and transporting zone and at least one of a hole injection and transporting zone and a mixed charge transport layer. One or both of the electron injection and transporting zone and the mixed charge transporting layer comprises an azole compound represented by formula I and / or II. The provision of the novel azole compounds of the invention as electron transport materials within an organic electroluminescent device advantageously reduces power consumption and increases power conversion efficiency within the device and as such, are suitable for a variety of display applications.

A synchronous rectification circuit for a power converter includes a power switch coupled to a transformer and an output capacitor and a switching control circuit configured to provide a control signal to the power switch in response to a first state and a second state of the voltage across the power switch. In the switching control circuit, the second state is determined prior to the first state is determined. In an embodiment, the switching control circuit includes a voltage comparing unit configured to act in response to the first and second inputs. The voltage comparing unit is also configured to output a logic signal according to the voltage difference between the sensed voltage drop across the power switch and a reference threshold voltage. A logic processing circuit is coupled to the voltage comparing unit and configured to provide the first state and the second state of the voltage across the power switch.

A solar cell comprising at least one nanostructure-film electrode is discussed. The solar cell may further comprise a different conducting material, such as a conducting polymer, to fill pores in the nanostructure-film. Additionally or alternatively, the solar cell may comprise an electrode grid superimposed on the nanostructure-film. Likewise, the solar cell may have a single or multiple active layer(s), wherein nanostructure-film(s) may form at least semi-transparent anode(s) and / or cathode(s) through use of buffer layer(s).

The invention relates to a hybrid driving system and a gear operating method thereof. The system comprises an internal-combustion engine, a first motor, a second motor, a planet coupling mechanism, a retarding mechanism and a differential mechanism, wherein an output shaft of the internal-combustion engine is connected with an input shaft of the first motor; an output shaft of the first motor is connected with an output shaft of the second motor by a first clutch; and the output shaft of the second motor is connected with one of a sun wheel and a gear ring of the planet coupling mechanism at the position of the axial direction of the output shaft, and output shaft of the second motor is connected with the other one of the sun wheel with a brake and the gear ring by a second clutch at the other position of the axial direction of the output shaft. In the hybrid driving system, two gear levels of forward gears of an automobile are formed by adjusting the planet coupling mechanism, so that operating modes and corresponding gears are selected flexibly according to different running work conditions of the automobile to achieve the effects of low emission and oil consumption, high kinetic energy and the like of the integral automobile.

Organic and organic / inorganic hybrid bulk heterojunction photovoltaic devices with improved efficiencies are disclosed. The organic photovoltaic device comprises a photoactive polymer:fullerene C60-carbon nanotube (polymer:C60-CNT) composite as a component of the active layer. Under light irradiation, photoinduced charge separation at the polymer:C60 interface is followed by electron transfer from C60 onto CNTs for efficient electron transport towards an electrode. The organic / inorganic hybrid photovoltaic device comprises quantum dots and carbon nanotubes. Power conversion efficiency enhancement methods of polymer-CNT based photovoltaics are also provided.

The invention discloses an electrothermal composite ceramic brick and a preparation method thereof. An electrothermal coating layer, a guiding-out wiring electrode, a coating insulation packaging waterproof layer and an application foaming ceramic layer coat an unglazed surface of a ceramics substrate in order. The electrothermal coating layer coats the unglazed surface of the ceramics substrate in an electrothermal slurry form, the electrothermal slurry permeates the green body of the ceramics substrate, and the penetration depth is less than the thickness of the ceramics substrate and more than 0.5mm. Because of the penetration, the electrothermal coating layer of the electrothermal composite ceramic brick is combined with the ceramics substrate tightly, a surface heating mode is achieved, the thermal efficiency is high, normal and safe usage can be achieved under a voltage of 24-380V, the heating power is 90-120w / m<2>, and the temperature of the ceramics substrate can reach 18-50 DEG C through a temperature control device. The insulation packaging waterproof layer and the foaming ceramic layer outside the electrothermal coating layer can prevent heat from outward transmission effectively, heat loss is lowered, and the whole safety and reliability of the ceramic brick are raised.

Disclosed are a semiconductor device and method of manufacturing the same comprising a substrate, a mesa region adjacent to the substrate, an electroplated metal layer, for reducing the thermal resistance of the device, surrounding the mesa region, an insulator layer separating a side portion of the mesa region from the electroplated metal layer, a heat sink, a bonding layer adjacent to the heat sink, and a second metal layer in between the substrate and the heat sink, wherein the substrate is adjacent to the bonding layer, and wherein the electroplated metal layer dimensioned and configured to have a thickness of at least half a thickness of the mesa region; and to laterally spread heat away from the mesa region. The mesa region comprises a first cladding layer adjacent to the substrate, an active region adjacent the first cladding layer, and a second cladding layer adjacent to the active region.

The invention provides a large-power intelligent dimming multiple-output power supply for suppressing electric surge with a field-effect transistor. The power supply comprises an electric surge suppression unit, an LLC (Inductor-Inductor-Capacitor) resonance conversion unit, a synchronous rectification unit and more than one constant-current-output intelligent dimming unit, wherein a power resistor in the electric surge suppression unit is connected in parallel with the source electrode and the drain electrode of a field-effect transistor, and the loss of an electric surge suppression circuit is very low due to the extremely small on-resistance of the field-effect transistor so that the whole efficiency of the power supply is improved. The invention acquires the output efficiency up to 95 percent by the optimization design of parameters of an LLC resonance network, the constant-current-output intelligent dimming unit circuit of the invention increases the mean value of the output current by increasing the duty cycle of an output current when sensing infrared rays of a human body; and otherwise, the constant-current-output intelligent dimming unit circuit decreases the duty cycle of the output current but not decreases the peak value while no body passes by so as to ensure LED luminous power and prevent light from scattering over the ground.

Provided is a DC-DC converter with improved power conversion efficiency. A transistor which is incorporated in the DC-DC converter and functions as a switching element for controlling output power includes, in its channel formation region, a semiconductor material having a wide band gap and significantly small off current compared with silicon. The transistor further comprises a back gate electrode, in addition to a general gate electrode, and a back gate control circuit for controlling a potential applied to the back gate electrode in accordance with the output power from the DC-DC converter. The control of the potential applied to the back gate electrode by the back gate control circuit enables the threshold voltage to decrease the on-state resistance when the output power is high and to increase the off-state current when the output power is low.

Provided is a solar cell including: a first electrode; an electron transport layer positioned on the first electrode; a light absorber; a hole transport layer; and a second electrode, wherein the light absorber contains a solid-solution of at least two organic-metal halides with a perovskite structure, having different compositions from each other.

The invention discloses a permanent magnetic direct-drive type offshore wind power plant grid-connected system topology structure and a control method thereof. A grid-connected system comprises a DC bus current collection type wind power plant, a wind field network-side converter station, a dual-stage boost transformer, an offshore rectification station, a seabed DC cable, a shore inversion station, a grid-connected side boost transformer and a land power grid which are successively connected, wherein the DC bus current collection type wind power plant employs a DC bus current collection topology structure and comprises multiple groups of wind turbines which are successively connected, a permanent magnetic synchronous generator, a machine-side rectifier and a DC bus for current collection. The control method is that the machine-side rectifier employs dual-closed-loop control of a rotating speed outer loop and a current inner loop, the wind field network-side converter station employs dual-closed-loop control of a voltage outer loop and the current inner loop, the offshore rectification station employs control of fixed AC voltages and fixed frequencies, and the shore inversion station employs dual-closed-loop control of fixed DC voltages and fixed reactive power. According to the invention, multi-machine parallel-connected operation can be realized, the electric energy conversion efficiency is improved, and the grid-connected AC harmonic quantity is reduced.

A tandem photovoltaic device and a method for fabricating the photovoltaic device is disclosed. The tandem photovoltaic device comprises two or more photovoltaic layers laminated to each other, each of which including a semiconductor electrode, an electrolyte layer and a counter electrode. A counter electrode of the upper photovoltaic layer is patterned in a grid shape so as to include a plurality of light-transmitting portions, which permit transmission of light to the lower photovoltaic layer. The tandem photovoltaic device has the advantages of high power conversion efficiency and degree of integration. Advantageously, the tandem photovoltaic device can reduce electric power generation costs.

An organic solar cell and a method of manufacturing the same. This invention relates to a method of manufacturing an organic solar cell including forming nano patterns on a photoactive layer using a nanoimprinting process, and applying a cathode electrode material on the photoactive layer having the nano patterns so that the cathode electrode material infiltrates the nano patterns of the photoactive layer, thus increasing electron conductivity and efficiently forming a pathway for the transfer of electrons, and to an organic solar cell manufactured through the method. This method reduces loss of photocurrent occurring as a result of aggregation of an electron acceptor material and improves molecular orientation of an electron donor in the nanoimprinting process to thus increase cell efficiency. Thereby, the organic solar cell having high efficiency is manufactured at low cost through a simple manufacturing process. The method can be applied to the fabrication of organic solar cells which use an environmentally friendly and recyclable energy source.

In one aspect this invention provides a DC-DC converter that has a switch mode part for coupling between a DC source and a load, the switch mode part providing x amount of output power; and that further has a linear mode part coupled in parallel with the switch mode part between the DC source and the load, the linear mode part providing y amount of output power, where x is preferably greater than y, and the ratio of x to y may be optimized for particular application constraints. In a further aspect there is a radio frequency (RF) transmitter (TX) for coupling to an antenna, where the TX has a polar architecture having an amplitude modulation (AM) path coupled to a power supply of a power amplifier (PA) and a phase modulation (PM) path coupled to an input of the PA.

Disclosed herein is an optical transmission apparatus for visible light communication. The optical transmission apparatus includes a power conversion unit, a drive unit, an encoding unit, a control unit, and a detection unit. The power conversion unit provides Direct Current (DC) power to the lighting LED lamps. The drive unit is operated using a switching drive method and supplies operating current to the lighting LED lamps. The encoding unit is connected to an external network, receives and encodes data, and provides it to the drive unit. The control unit controls the operation of the power conversion unit, the drive unit, and the encoding unit. The detection unit measures the strength of a visible light signal sent by the lighting LED lamps.

To both increase the efficiency of conversion into EUV radiation energy and also increase the amount of emerging EUV radiation in an EUV source a discharge tube is connected to a gas supply space for supply of the discharge gas which in located radially with respect to an optical axis. The discharge gas is supplied to the discharge space through the gas supply space, passes through the center opening of the anode, emerges from the discharge part and is afterwards evacuated from an evacuation opening. The anode and the cathode are connected to a pulse current source. Discharge plasma is produced and EUV radiation is formed by a heavy current pulse from the pulse current source within the discharge space of the discharge tube. The EUV radiation which has formed passes through a through-opening of the anode and is emitted to the outside.

A LED driving semiconductor circuit of the present invention includes a first input terminal connected to a light-emitting diode, a switching device block having a first FET and a first switching device, a reference voltage terminal which is connected to the first FET and outputs the reference voltage, a start / stop circuit which outputs a start signal when the reference voltage is equal to or larger than a predetermined value and outputs a stop signal when the reference voltage is less than the predetermined value, a current detection circuit which detects the current flowing through the first switching device, and a control circuit which controls ON / OFF of the first switching device intermittently at the predetermined frequency based on the output signal of the start / stop circuit and the output signal of the current detection circuit so that the constant current flows through the light-emitting diode.

A parallel optical fiber amplifier having a configuration in which a C-band silica-based erbium-doped fiber amplifier (EDFA) stage and an L-band EDFA stage are coupled together in parallel in such a fashion that a reverse amplified spontaneous emission (ASE) light emitted from the C-band and / or L-band EDFA stage is reused as a secondary pumping source for an amplification in the L-band EDFA stage. In the optical fiber amplifier of the present invention, the reverse ASE light emitted from the C-band EDFA stage and the reverse ASE light emitted from the L-band EDFA stages supplied to the L-band EDFA stage so that they can be reused for improving the power conversion efficiency of the entire system and for reducing the noise factor thereof.

The invention provides an energy-storage voltage-balanced power electronic electric energy converting system and a control method thereof. The energy-storage voltage-balanced power electronic electric energy converting system is composed of an energy storage module, a voltage-balanced converter, a power-grid-side inverter, a power grid load, an energy-storage-side inverter and an independent load. Through control over the high-frequency soft-switching voltage-balanced converter, balanced control over an energy storage unit or module is realized, the service life of energy storage equipment is prolonged, the use cost is reduced, and meanwhile, multiple routes of isolation direct voltage are provided for the power-grid-side inverter. The energy storage unit or module is charged and discharged through the electric energy converting system, electric isolation of energy storage and a power grid is realized, interaction is formed with the power grid, and the purposes of peak load shifting, harmonic suppression and reactive compensation are realized. The energy-storage voltage-balanced power electronic electric energy converting system is realized through modularized design and has the advantages that electric isolation of the power grid and the energy storage side is realized, control is simple, the size is small, the efficiency is high and the cost is low.

The invention relates to the technical field of breakwater engineering and wave power generation, in particular to a floating breakwater generation device arranged in open sea. The floating breakwater generation device comprises floating members, air turbine generator sets, air chambers, airflow passages, mooring systems and signal transmission devices, and is characterized in that the floating members are respectively connected with concrete anchor blocks at the sea bottom through anchor chains; a plurality of wave dissipating perforations penetrating through a floating body are formed in the head-sea face of each floating member; the air turbine generator sets are respectively arranged in the airflow passages; the floating bodies are driven by waves to vertically move, so that water in the air chambers vibrates and air in the air chambers is pushed to move, and the air turbine generator sets are further driven to generate electricity. The floating breakwater generation device disclosed by the invention has the characteristics of being stable in structure, low in erection cost, high in generation conversion efficiency, convenient to maintain, and the like, and can be applied to sea areas with deep water, high waves and complex terrain; while wave impacts are weakened and a steady water area environment is provided for surrounding water areas, the waves can be converted into electric energy, and the electric power supply problem of harbor district or island residents is effectively solved.

The invention discloses a bidirectional direct current converter based on an immittance network, and a digital control system and a digital control method of the bidirectional direct current converter. The bidirectional direct current converter based on the immittance network comprises a storage battery, a low-voltage-side filter capacitor, a first active full-bridge circuit, the immittance network, a high-frequency transformer, a second active full-bridge circuit and a high-voltage-bus-side filter capacitor. The digital control system comprises a first voltage sensor, a second voltage sensor, a current sensor and a digital signal processing (DSP) digital controller, wherein the DSP digital controller comprises a BUCK controller, a BOOST controller, a signal conditioner, a first selective switch and a second selective switch. According to the basic characteristics of the immittance network, the two active full-bridge circuits in the bidirectional direct current converter can operate with high power factor, and the current stress of a switching tube can be greatly reduced. By the adoption of the system and the method, according to the characteristics of the immittance network, the zero-current turn on and zero-current turn off of all switching devices of a high-voltage-side active full-bridge circuit are realized, and the efficiency of the converter is improved.

Photovoltaic nanocomposite and solar cell device including the photovoltaic nanocomposite, where the photovoltaic nanocomposite includes a film of solution processed semiconductor materials having an n-type material selected from n-type quantum dots and n-type nanocrystals, and a p-type material selected from p-type quantum dots and p-type nanocrystals, and where the n-type material has a conduction band level at least equal, compared to vacuum level, to that of the p-type material, the p-type material has a valence band at the most equal, compared to vacuum level, to that of the n-type material. at least a portion of the n-type material and at least a portion of the p-type material are present in a bulk nano-heterojunction binary nanocomposite layer having a blend of the n-type material and the p-type material.

Disclosed herein are a polymer solar cell, comprising a substrate, a first electrode, a hole injection layer, a photoactive layer, and a second electrode, characterized in that an electron-accepting layer is formed between the photoactive layer and the second electrode, and a method of manufacturing the polymer solar cell. The polymer solar cell comprises an electron-accepting layer between the photoactive layer and the second electrode, thereby assuring excellent power conversion efficiency. Furthermore, high power conversion efficiency can also be attained in a low-temperature thermal annealing process.

A hybrid photovoltaic cell comprising a composite substrate of a nanotube or nanorod array of metal oxide infiltrated with a monomer precursor and subsequently polymerized in situ via UV irradiation. In an embodiment, the photovoltaic cell comprises an electron accepting TiO2 nanotube array infiltrated with a photo-sensitive electron donating conjugated polymer. The conjugated polymer may be formed in situ through UV irradiation polymerizing a monomer precursor such as 2,5-diiodothiophene (DIT).