31results about How to "Solve the low conversion efficiency" patented technology

The invention provides a series-parallel hybrid system and a vehicle working mode decision method. The series-parallel hybrid system comprises a traditional power device and a motor driving device; the traditional power device and the motor driving device can be respectively coupled to driving axles of a vehicle to drive wheels to rotate; and the traditional power device comprises a first engine,wherein the series-parallel hybrid system further comprises a power battery device and a vehicle-mounted power generation device, wherein the power battery device is arranged to store electric power and supply power to the motor driving device and / or other vehicle electric appliance loads; the vehicle-mounted power generation device comprises a second engine and a power generator; and the second engine is arranged to drive the power generator to generate power and can supply power to any one or combinations of the motor driving device, the power battery device and other vehicle electric appliance loads. According to the series-parallel hybrid system, the mechanical structure is comparatively simple; and problems of range anxiety, lower conversion efficiency under high speed condition, toocomplicated automobile system and so on can be simultaneously solved.

The invention provides an inversion power supply system. A first bus capacitor is connected with an ac-dc converting circuit via a first selector switch when a dc bus voltage of the first bus capacitor cannot satisfy inversion output requirement of the ac-dc converting circuit, and the dc bus voltage of the first bus capacitor is secondarily boosted via the ac-dc converting circuit, thereby broadening the range of output voltage of a second bus capacitor, satisfying the inversion output requirement of the ac-dc converting circuit, ensuring wide voltage input of a battery, satisfying wide input / output voltage range of the inversion power supply system, and prolonging effective service life of the battery. The ac-dc converting circuit is used to boost the dc bus voltage of the first bus capacitor, thereby solving the problem that conversion efficiency is low due to the fact that in the prior art, the wide input / output voltage range of the inversion power supply system is satisfied by changing the duty ratio of a PWM converter or the resonant frequency of a resonant converter.

The invention provides a p-type silicon solar cell and a preparing method thereof. The p-type silicon solar cell comprises a p-type silicon substrate. The front surface of the p-type silicon solar cell is provided with an n<+> doped layer and a reflection reducing layer. Front anodes which penetrate the reflection reducing layer are manufactured. The front anodes are connected with the n<+> doped layer. The back surface of the p-type silicon substrate is provided with a back passivation layer. The back passivation layer comprises a film layer which is made of a ferroelectric film material or a doped ferroelectric film material. A back electrode is manufactured on the back passivation layer through a printing process and a sintering process. According to the p-type silicon solar cell, the ferroelectric film material is used as the main material of the back passivation layer of the cell, thereby greatly improving the open circuit voltage and shortcircuit current of the cell and improving conversion efficiency of the cell.

The invention discloses a gene transformation method for summer black grapes. The method comprises the steps of material selection from tissue culture seedling leaves, leaf stalks and stem fragments, infection, co-culture, screening culture and rooting culture. Material selection is optimized, growth portions and growth time of explant leaves are specifically regulated, and the phenomenon that the working efficiency is low due to blindness of material selection is avoided; meanwhile, the portions, including grape leaf stalks and stem fragments, except the leaves, of the explants are selected, better operation can be performed by using the leaf stalks and the stem fragments, the gene transformation efficiency can be improved, and the transformation efficiency can reach 20% or above; the problem of pollution of agrobacterium and infectious microbes in an agrobacterium-mediated method is solved; the problem that the grape conversion efficiency is low is solved; the problem that grape transgene transgenosis, transgenic test and farm transplanting period is long is solved, and the period is shortened; the problems that the transgenic test workload is large and workloads are large are solved, the detection method is simplified, and the detection speed is increased.

The utility model relates to an independent photovoltaic power generation railway power supply control system. In railway electric equipment, there are a large impact load, a communication signal high stability load and other equipment with a special electric demand. Solar photovoltaic power generation is greatly influenced by an environment. In a photovoltaic power generation system, problems that solar energy conversion efficiency is low and power supply system power is insufficient generally exist. The system collects sun radiation energy and converts into direct-current electric energy. After conversion, charging is performed on a storage battery. A direct current is converted into an alternating current so that a load can use the alternating current. Load working voltage current information monitored by a working state collector and environment information monitored by an environment illumination collector and an environment temperature collector are transmitted to an energy storage system controller. After logic processing, control to a charging conversion module and an inversion conversion module is performed. According to a railway load operation state and an environment state, continuous and smooth electric energy is adjusted, controlled and output; photovoltaic power generation power quality and efficiency are increased and continuous stability of power supply transmission is guaranteed.

The invention provides an n type silicon solar cell and a preparation method therefor. The n type silicon solar cell comprises an n type silicon substrate, wherein a p type doped layer, a front surface passivating layer and an anti-reflection layer are manufactured on the front surface of the n type silicon substrate from the bottom up in sequence; the front surface passivating layer is a monox or silicon nitride film layer; a front surface electrode is manufactured by penetrating the anti-reflection layer and the front surface passivating layer; the front surface electrode is connected with the p type doped layer; an n+ doped layer is formed on the back surface of the n type silicon substrate through a doping manner; a back surface passivating layer is manufactured on the n+ doped layer; the back surface passivating layer comprises a film layer prepared from a ferroelectric film material or a doped ferroelectric film material; a full-back metal film is manufactured on the back surface passivating layer; and a back surface electrode of the cell is formed by the full-back metal film. According to the n type silicon solar cell, the ferroelectric film material is adopted as the main raw material of the back surface passivating layer of the cell, so that the open-circuit voltage, the short-circuit current and the fill factor of the cell can be well improved, and the conversion efficiency of the cell can be improved.

The embodiment of the present invention discloses a multi-antenna energy transmission device, method and device, including a sending device and a receiving device, the sending device includes a plurality of sending antennas; the receiving device includes a plurality of receiving antennas, a plurality of rectifiers and a power splitter ; The sending device formulates an energy beamforming scheme and an energy split coefficient according to the parameter information, and transmits radio frequency energy to the receiving device according to the energy beamforming scheme, and transmits the energy splitting coefficient to the receiving device at the same time. Each receiving antenna in the receiving device can transmit the received RF energy to the corresponding power splitter; each power splitter is connected to the corresponding rectifier, and can adaptively split the RF energy collected by the receiving antenna according to the energy split coefficient processing, so as to ensure that the radio frequency energy transmitted to each rectifier is within an appropriate range, effectively solving the problem that the rectifier is limited by the initial voltage and saturation voltage, resulting in low energy conversion efficiency, and improving the conversion efficiency of radio frequency energy.

The invention discloses a method for improving the regeneration efficiency of an apple transgenic material. The method comprises the steps of culturing a tissue culture seedling of bredia rotundifolia in an expanding propagation culture medium for a month, cutting off callus at a stem base part by using a scalpel, then transplanting a regenerated stem section into a new culture medium; culturing the regenerated stem section in the expanding propagation culture medium for a month, transversely cutting the midrib of a fully-stretched functional leaf for two or three times, infecting by using agrobacterium, and then inoculating into a predifferentiation culture medium; carrying out dark culture for 2-4 days, and then transferring to a differentiation culture medium; after the dark culture is carried out for two weeks, culturing under light until resistant buds are differentiated; transplanting the resistant buds into a subculture medium, and further culturing for 20-30 days; selecting regenerated plantlets with the height of 1.5cm, and transplanting the selected regenerated plantlets into a rooting medium, culturing for a month, and transplanting. After the method is adopted, the detached leaf regeneration efficiency reaches 80.33%, the expanding propagation coefficient reaches 8.2, and the rooting rate reaches 96.38%.