60results about How to "Avoid design difficulties" patented technology

The invention discloses an inductance regulating switch capacitor-type passive clamping soft switching high-gain boost-type converter which comprises a power switch tube, a clamping diode, a rectification diode, a coupling inductor and a regulating inductor and has the following basic functions: the zero-current turning-on of the power switch tube is realized through utilizing the leakage inductance of coupling inductance; the soft turning-off of the power switch tube and lossless transfer of leakage inductance energy are realized through the passive clamping circuit consisting of the clamping diode and a clamping capacitor; the high-gain output of the converter is realized through utilizing a second winding of the coupling inductor and the switch capacitor; the turn ratio of the coupling inductance is prevented from being over-high by utilizing the inductance to regulate and output voltage range; the volume of a magnetic element is reduced by utilizing the bidirectional operation of the magnetic element; the converter is simple in structure, is convenient to control; and loss energy elements are not arranged in the circuit, and the efficiency can be improved. The inductance regulating switch capacitor-type passive clamping soft switching high-gain boost-type converter provided by the invention is mainly applied to the field of renewable energy source and novel energy source power generation with low working voltage level, such as photovoltaic power generation and fuel battery power generation.

The invention relates to a method of optimallying designing a closed-winding permanent magnet brushless DC motor on the basis of differential evolution algorithm and finite element time-stepping method. The method includes: according to the particularity in the closed-winding permanent magnet brushless DC motor, by considering a body and a control part of the motor, using the cost in torque density and unit torque of a system as an optimization target; using constraint conditions such as parallel branch circulation, power factor, efficiency, torque output, fluctuation, heating, structural strength and the like. The method has the advantages that design schemes of each generation are varied, intersected and selected for differential evolution, and a Pareto optimal solution set is updated continuously; in order to ensure design accuracy, the finite element time-stepping method is applied to accurate dynamic simulation computation of the closed-winding permanent magnet brushless DC motor; the reliable and accurate method is provided for the design optimization of the closed-winding permanent magnet brushless DC motor, and the development of the novel motor is quickened.

The invention relates to a novel low-temperature combined cooling, heating and power (CCHP) system based on a heat pump. Currently, no novel low-temperature CCHP system based on the heat pump with a simple structure and a reasonable design exists. The novel low-temperature CCHP system based on the heat pump comprises a high-pressure steam pipe, a steam turbine, a power generator, a condenser and a boiler connecting pipe, and is characterized by also consisting of a heating low-pressure steam pipe, a heating condensate pipe, a power plant after-heat single-effect heat pump unit, a refrigeration single-effect absorbing heat pump unit, a heat pump unit loop pipe, a loop circulating pump, a user refrigeration pipe, a cooling tower, a cooling tower water inlet pipe, a cooling tower water outlet pipe, a cooling water circulating pump, a power plant circulating cooling water pipe, a heat pump cooling tower, a cooling tower circulating pipe, a heating single-effect absorbing heat pump unit, a heating heating pipe, a heat pump circulating pipe and a user heating pipe; the heating low-pressure steam pipe is connected with the refrigeration single-effect absorbing heat pump unit; and the heating condensate pipe is connected with the power plant after-heat single-effect heat pump unit. The novel low-temperature CCHP system based on the heat pump has the advantages of reasonable structural design, energy saving, environmental friendliness and high heat utilization rate.

An improved interface circuit is provided herein for translating a relatively high input voltage into a relatively low output voltage using only low voltage transistors and a single, low voltage power supply. According to one embodiment, the interface circuit includes a power supply, a pair of input transistors with source terminals coupled together for receiving a relatively low voltage from the power supply, and a current sense amplifier with a pair of input terminals, each coupled to a drain terminal of a different one of the pair of input transistors for receiving a pair of differential currents and for generating a pair of differential voltages therefrom.

The present invention discloses a parallel sampling system basing on the super-wideband which is projected randomly, and the invention mainly settles the problem of complex realization and no suitability for processing the common super-wide band in the homogeneous system. The system is mainly composed of a function generating module, a parallel sampling module and a linear operating module. In the system the function generating module adopts a pseudorandom sequence generating module for generating a group of pseudorandom sequence for inputting to the parallel sampling module. The parallel sampling module realizes the projection operation of the upper-wide band analog signal on the self-contained pseudorandom space and obtains the digital projection coefficient signal for inputting to the linear operating module. The linear operating module adopts the M-input and M-output linear structure and conveys the output projection coefficient signal of the parallel sampling module to the parallel digital sampling signal and then outputs. The invention has the advantages of low complexity in the circuit operation, being easily realized and broad applying sphere. The invention can be used for executing digitization sampling processing to the super-wideband signal.

The invention relates to a polylactic acid/polyester alloy and a preparation method thereof. The polylactic acid/polyester alloy comprises the following components in percentage by weight: polylactic acid, polyester, a compatilizer, a flexibilizer, an antioxidant and a lubricant. The preparation method comprises the following steps: firstly, proportioning the raw materials and mixing at a room temperature; and respectively carrying out melting extrusion, carrying out ultrasonic treatment at the first late stage, extruding at the second stage and pelletizing, so as to obtain degradable, high-impact-resistant and high-heat-resistant polylactic acid/polyester alloy. Compared with an existing method, the controllable ultrasonic treatment is utilized; and a similar polylactic acid-g-polyester structure is formed by in-situ reaction, so that the heat resistance of the polyester and the biodegradability of the polylactic acid are reserved; and meanwhile, a toughening system with a core-shell structure is formed in an alloy system through interface interaction of a special toughening compatilizer, so that the alloy product with high impact resistance, high heat resistance and high biodegradability can be obtained.

The invention discloses an active antivibrator and active vibration-proof method of an overhead transmission line. The active antivibrator comprises a shell, a power source, a control circuit, an electric motor, a transmission mechanism and a vibration-proof actuating mechanism, wherein the shell is provided with a fixing element which is used to fix the antivibrator on a line, the control circuit, electric motor and transmission mechanism are arranged in the shell and the power source provides electrical energy; the control circuit controls the movement of the electric motor, the electric motor drives the vibration-proof actuating mechanism to move and change the centre-of-gravity position through the transmission mechanism so as to counteract the vibration of the lead by means of reaction and realize the aim of inhibiting the breeze vibration of the lead.

The invention discloses a long-span concrete prismatic surface arch reticulated shell roof structure and a manufacturing method thereof. The prismatic surface of the structure is internally connectedto a round curve face, after a giant cylindrical bearing grid is formed by a main folding arch and a regression line beam, dense rib flat plates are divided in the giant grid, roof slope toes are supported on a side frame beam, after a gutter is formed to bear roof thrust by cooperating with the side frame beam, the thrust is transmitted to an anti-thrust structure composed of an inclined rod anda side frame column, and a roof end is supported on a gable wall frame. Manufacturing of the structure can adopt a total cast-in-place concrete mode or prefabricated method. The long-span concrete prismatic surface arch reticulated shell roof structure is applied to roofs of buildings such as warehouses, convention and exhibition and auditoriums, and has the advantages of being good in durability,high in rigidness, high in bearing capacity, low in construction cost and the like.

The invention discloses a series sewage intercepting collection pipe method for treating an urban black and odorous water body. According to the method, bearing mechanisms corresponding to confluent main pipes are arranged on a river channel revetment, or positions corresponding to the confluent main pipes in a river channel are piled, the bearing mechanisms or piles are used for supporting and jacking the confluent main pipes, a water outlet of each confluent main pipe is communicated with an intercepting branch pipe, an intercepting well is arranged at a water outlet of each intercepting branch pipe, all the intercepting wells are communicated with each other through pipelines to form intercepting main pipes, a water outlet of each intercepting main pipe is communicated with a municipal sewage pipe network, sewage and rainwater intercepted by the intercepting wells are conveyed to the municipal sewage pipe network through the intercepting main pipes, sewage of the municipal sewage pipe network is communicated to a water inlet of a sewage treatment plant for treating the received sewage, and treated effluent is drained into the river channel. The source of the black and odorous water body is treated, and the method is simple, efficient and low in investment cost.

The invention discloses a microscopic imaging objective lens for fiber core identification of an optical fiber fusion splicer and an imaging method thereof. The microscopic imaging objective lens hasa coaxial transmission type optical imaging structure and comprises a front group formed by double gluing of a concave-convex spherical positive lens and a crescent-shaped spherical negative lens anda rear group formed by double separation of a double-convex spherical positive lens, a crescent-shaped spherical negative lens and a crescent-shaped spherical thick positive lens, wherein the front group and the rear group are arranged successively in a light incident direction. According to the invention, the imaging objective lens has advantages of high resolution, small distortion, good imagingperformance, long optical cylinder, low processing cost, simple and compact structure and the like; the imaging performance of the imaging objective lens reaches the diffraction limit; the resolutionis as high as 2 micrometers and the diameter is far higher than the diameter of the end surface of an optical fiber by 10 micrometers; and the magnification reaches 5 times and fine imaging can be carried out on the optical fiber end face, high-precision alignment is realized, and the type of the optical fiber can be accurately recognized. Meanwhile, problems of large welding loss, unstable welding and the like in the prior art are solved; and the use requirements of a fiber core alignment type optical fiber fusion splicer are met.

The invention discloses a serial port loading device and method for an embedded chip, and relates to the field of embedded chips, the serial port loading device comprises an embedded chip, a hardwarecontrol circuit, a USB conversion chip and an upper computer; and the embedded chip is in communication connection with the upper computer through the hardware control circuit and the USB conversion chip, so that the embedded chip and the upper computer realize serial port file loading. According to the invention, universal downloading and burning of the embedded chip are realized on the whole, the selection range of materials of the FLASH memory in the later stage is expanded, the ROM storage space and GPIO resources of the embedded chip are saved, and the design difficulty and risk of the ROM in the aspect of burning are avoided.

The invention relates to a lever type low-temperature thermal switch for coupling a low-temperature refrigerator and a cooled device, which comprises the components of: a metal cold end and a metal hot end which are respectively connected with a cold head and a refrigerated element of the refrigerator; a ceramic fixing cylinder for fixedly connecting the cold end with the hot end; a contraction rod which contacts with the cold end; a cylindrical contact block which switches off and on the thermal switch; a metal lever and a ceramic supporter which matches with the metal lever; and an elastic heat-conductive strip with a contraction pretightening force. Through contraction and restoring of the contraction rod with a thermal expansion coefficient, displacement of the lever is generated, thereby realizing contact and separation between the cylindrical contact block and the cold end. Different material selections and lever proportions can realize convenient adjustment for gap size. Requirements for normally open, normally closed and opening/closing in actual operation can be satisfied. The lever type low-temperature thermal switch further has advantages of high unidirectional performance, sensitive reaction, small size and low cost.

The embodiment of the invention provides a control method of an AC-DC converter, a control device, an output system and a storage medium, and relates to the technical field of electrical control. Thecontrol method comprises the steps of obtaining a three-phase input parameter, a resonance parameter and a direct-current output parameter of the AC-DC converter, and determining a working mode of theAC-DC converter according to the three-phase input parameter and the direct-current output parameter; determining a state diagram of the AC-DC converter under the working mode according to the three-phase input parameter, the resonance parameter and the direct-current output parameter; obtaining the duration of each excitation state according to the parameters of each excitation state in the state diagram; and controlling the PWM conduction duration of a corresponding switch transistor in a switch matrix of the AC-DC converter according to the duration of each excitation state. When PWM control is adopted, the working frequency of the switch transistors is fixed, and particularly high performance requirements for input and output filter circuits are avoided, and therefore the technical problem that the design of the AC-DC converter is difficult due to the fact that the PDM is adopted is avoided, and the research and development cost of the AC-DC converter is reduced.

The invention discloses a centrifugal bead-making method of lithium oxide beads in nuclear fusion blankets and belongs to the technical field of material forming and control. The lithium oxide centrifugal bead-making method comprises the following steps that molten or pulped lithium oxide is dripped or flows into a rotating shaft disc, under the action of centrifugal force, the lithium oxide is made into beads, and the beads are collected and cooled through coolants to achieve fixing and forming. The lithium oxide bead-making process and device is simple in operation, universal and economic and applicable to preparation of various lithium oxide beads through a melting method or a wet process, the discharging and ball-making speed is fast, design and manufacturing difficulty of the discharging hole and the bead-making device is avoided, yield and particle size of made balls can be flexibly adjusted through the adjustment of material flow of lithium oxide and/or the rotating speed of the shaft disk, convenience and high efficiency are obtained, and preparation scale of lithium oxide tritium breeding agent beads can be greatly improved.

The invention relates to a plane-form frequency reuse antenna sub-reflection surface. The sub-reflection surface comprises two function layers: a frequency selection layer and a phase shift layer. The frequency selection layer achieves the total transmission of a feedforward feed source, and achieves the total reflection of a feedbackward feed source. After the feedbackward feed source irradiates the phase shift layer, the reflection phase of an electromagnetic wave is changed, thereby enabling the phase center of the reflected wave to coincide with the focus of the main reflection surface of an antenna. The two function layers of the sub-reflection surface act jointly, and achieve the frequency reuse of the main reflection surface. The sub-reflection surface avoids a curved-surface form frequency selection layer, and can improve the rate of finished products.

The invention relates to a large-scale substation key facility monitoring system of a low-power wireless communication and a method. The system comprises an in-situ measurement and control device anda measurement and control background; the system further comprises a heater and a dehumidifier; the heater and the dehumidifier are installed in the closed cabinet of a substation; the in-situ measurement and control device is installed in the sealed cabinet, fire pool and cable trench of the substation; the in-situ measurement and control device monitors the temperature, humidity and liquid levelparameters of installation positions in real time and wirelessly transmits the temperature, humidity and liquid level parameters to the measurement and control background; and the measurement and control background starts and stops the heater or dehumidifier through the in-situ measurement and control device. Compared with the prior art, the system and method of the present invention can realizethe special monitoring of the key facilities of a large-scale substation.

A double-stator double-rotor flameproof motor comprises first and second rotors, first and second stators, a transmission shaft, a binding post, a conjunction box, a casing, an end cap and a bearing cap; the first and second rotor are connected to the transmission shaft successively, the first and second stators sleeve the first and second rotors respectively, the binding post is assembled in the conjunction box, the end cap and the bearing cap are assembled on the casing, and three main leads of a winding of the first stator and three main leads of a winding of the second stator are connected to the binding post with the leads in the same phase in parallel connection. The design difficulty of the flameproof motor of the power of 315kW and voltage of 1140V is overcome effectively, requirement for the output power is satisfied in the aspect of electromagnetic performance, use of raw materials is reduced effectively, and the installation difficulty of the whole motor is reduced greatly.

The invention discloses a new process for preparing 1,2-propylene glycol from biological glycerol through low-temperature and low-pressure hydrogenation. In the method, the biologically prepared glycerol is used as a raw material, Cu-SiO2 catalyst is adopted, and the 1,2-propylene glycol is catalytically prepared under extremely mild reaction conditions in two hydrogenation steps, wherein during reaction of the first step, the glycerol is dehydrated under the action of the catalyst to generate an intermediate product acetol; and during the reaction of the second step, the acetol is hydrogenated under the action of the catalyst to generate the 1,2-propylene glycol. The process has the advantages of easiness and convenience in reaction process, easiness in operation, high controllability, low reaction temperature, low reaction pressure, high target product yield and the like.

The embodiment of the invention provides a system design method and electronic equipment. The system design method comprises the following steps: determining terminal type parameters; performing system design on the satellite communication system based on the terminal type parameter, wherein the terminal type parameters comprise at least one of the following factor items: a terminal antenna type, a terminal application scene, a terminal visual range, a terminal communication rate, a terminal moving speed, a transmitting antenna equivalent aperture of the terminal, a receiving antenna equivalent aperture of the terminal, maximum equivalent omnidirectional radiation power EIRP sent by the terminal, the equivalent temperature gain coefficient G/T received by the terminal, the maximum signal-to-noise ratio supported by the terminal, the maximum scheduling bandwidth of the terminal and the minimum access bandwidth of the terminal. According to the embodiment of the invention, the satellite communication system is simple and efficient in design.