284 results about "Electrical engineering technology" patented technology

The invention belongs to the technical field of electric appliances and electric engineering, and relates to a multifunctional modularized lithium electric cooker. An embedded handle is embedded in an upper cover with a heat-preserving layer, the middle of the upper cover with the heat-preserving layer is provided with an air outlet hole, a lateral thermoelectric film is attached to the outer side of a barrel-shaped outer container, and a barrel-shaped inner container is arranged on the inner side of the barrel-shaped outer container; an inner container upper cover covers the top of the barrel-shaped inner container, and the lower end of the barrel-shaped inner container is provided with a strainer; the barrel-shaped outer container is arranged on an inner and outer container supporting frame, the inner and outer container supporting frame is disposed on a bottom support, the center of the bottom support is provided with a bottom cooling air hole, a bottom thermoelectric film is attached to the surface of the bottom support, and the lower portion of the bottom support is provided with a lithium battery; a power supply cover plate is disposed on the outer side of the lithium battery; the inner side of the bottom of a shell is provided with a fan, and a bottom heat-preserving pad is arranged on the outer side of the bottom of the shell; one side of the barrel-shaped outer container is provided with a temperature sensor connected with a temperature display and control unit, and the shell is provided with the temperature display and control unit and a clock displaying, timing and setting unit. The multifunctional modularized lithium electric cooker is simple in structure, multifunctional, convenient to carry, safe to use, convenient to repair and maintain, high in utilization rate and good in heat preservation.

The present invention relates to the technical field of electrical engineering and discloses a PRBS disturbance injection-based power grid impedance online identification device. The device is mainly composed of a grid-connected inverter, a current loop controller, a sampling device and an impedance identification unit. The device is characterized in that the grid-connected inverter is connected with the current loop controller. When the grid-connected state is stable, the grid-connected inverter injects the PRBS disturbance into the power grid. During the injection process of a PRBS signal, a built-in output voltage THD is fed back to the controller, so that the THD value of the output voltage of the inverter is ensured to be smaller than 5%. The sampling device is connected with the PCC part of the power grid and is used for sampling and recording the voltage and the current at the PCC part of the power grid. The impedance identification unit is used for subjecting the sampled data of the sampling device to DFT analysis, and taking the average value of the amplitude and the average value of the phase of each harmonic component of the voltage and the current during the current sampling period. The method of the invention is high in precision, high in speed, strong in real-time property, wide in frequency range, lower in measuring cost and difficulty, and better in stability.

The invention relates to a neutral point direct-current restrainer of ground transformer, wherein it comprises blocking capacitor, thyristor solid switch connected to two ends of blocking capacitor, relative trigger unit, limit resistance, and bypass switch. The invention can effective restrain the neutral point direct current caused by high-voltage direct current, etc, to reduce noise, overheat, etc. And it has simple process and low cost, without external reverse voltage.

The invention provides a power grid micro meteorology calamity monitoring early warning system and an early warning method, relating to the electrical engineering technology field. The power grid micro meteorology calamity monitoring early warning system comprises a micro meteorology monitoring sub-platform, a micro meteorology calamity prediction sub-platform, a micro meteorology calamity early warning sub-platform and a system management sub-platform. The early warning method comprises steps of: obtaining meteorology data and micro meteorology data of a power transmission line from a monitoring device, performing icing prediction and wind deflection prediction according to the micro meteorology data to obtain an icing prediction area distribution result and a wind deflection prediction area distribution result, Q3 performing icing early warning level dividing and wind deflection early warning level dividing according to the icing prediction area distribution result and the wind deflection prediction area distribution result, and displaying an early warning prompt, and displaying meteorology monitoring data, prediction data and early warning data The power grid micro meteorology calamity monitoring early warning system and the early warning method solve problems that meteorology data collection is dispersed, information sharing is insufficient and transmission is delayed, communication efficiency is low and prediction accuracy is low.

The invention discloses a stability analysis method for a doubly-fed fan grid-connected system, and belongs to the technical field of electrical engineering. According to the method, small signal impedance models of a rotor side converter port and a network side converter port of a double-fed fan are built under polar coordinates; and a small signal impedance model of a network port of a power grid side is built under the polar coordinates. According to the built small signal impedance models of the rotor side converter port and the network side converter port of the double-fed fan, and smallsignal impedance model of the network port, calculation is performed to obtain generalized impedance of the ports of the double-fed fan and generalized impedance of the network port of the power gridside; the two generalized impedances are divided to obtain a corresponding ratio; and the stability of the doubly-fed fan grid-connected system is judged according to a Nyquist criterion. The method can be used for analyzing the stability of the doubly-fed fan grid-connected system, and provides a theoretical foundation for understanding an oscillation mechanism caused after access of large-scalewind power to a power grid.

The energy efficiency chaos analysis method of electrical equipment based on massive metering data belongs to the technical field of electrical engineering, and in particular relates to a chaos analysis method for energy efficiency of electrical equipment based on massive metering data. The present invention proposes a chaotic analysis method for energy efficiency of electrical equipment based on massive metering data, which uses an advanced analysis method for metering data combined with a test detection system to analyze the relationship between the use of user electrical equipment and the user's power consumption data, and then Obtain the user's electricity consumption habits and the load characteristic relationship of different electrical equipment. The present invention comprises the following steps: 1) adopt fuzzy C-means clustering (FCM) to determine the degree to which the comprehensive load characteristic of the user belongs to a certain cluster with the degree of membership, and put n industry users x _i (i=1,2,,,n) is divided into c fuzzy classes, and the cluster center of each class is obtained, so that the weighted error sum of squares function within the class can be minimized.

The invention provides a demonstration-free laser three-dimensional measurement method based on a reverse engineering technology and a device. A five-shaft linkage laser cutting machine usually needs one demonstration process before cutting, but original demonstration recording and returning process waste time and labor and is not easily and accurately controlled. An optical instrument is fixed on a laser cutting head, a motion control system of the cutting machine drives the optical instrument to move, and the optical instrument and a numerical control system of the five-shaft linkage laser cutting machine are utilized to form a borrowed-machine measuring system for finishing measurement of spatial point coordinates and obtaining point cloud data, then reverse engineering software is utilized to re-establish a CAD model of a workpiece, and further online planning on laser cutting postures and tracks is achieved according to the CAD model. The demonstration-free laser three-dimensional measurement method based on the reverse engineering technology and the device are used for online cutting of thin-wall and easily-deforming workpeices including large three-dimensional covering parts.

The invention relates to an ecological engineering technology for stopping riverway coastal pollutants from entering rivers and restoring vegetation communities. The ecological engineering technology consists of four basic unit systems, namely a land pollutant stopping and purification system, a slope protection system, a base construction system and a plant cultivation system; the units consist of physical materials and plants, wherein the pollutant stopping and purification system is built by materials such as plastic, woods, gravels, plants and the like; the slope protection system is built by materials such as woods or concrete, stone blocks, metal wires and the like; the base construction system is built by materials such as plastic, woods, soils, gravels, metal wires and the like; and the plant cultivation system consists of materials such as plants, plastic, soils and the like. The ecological engineering technology aims at land directional runoff pollution and side slope ecological structure construction of rural or urban suburban riverways, and has the advantages of fully and effectively collecting, detaining and purifying the land directional runoff pollution, particularly the runoff pollution of initial rain water, reducing the total amount of pollutants entering the riverway and realizing effective control on the riverway pollution; meanwhile, by the ecological engineering technology, a physical structure and a biologic structure of the riverway from the land direction to the water direction can be stabilized and perfected by building and restoring revetments and bases of the riverway, so a healthy, stable and developed riverway side slope biologic system is formed at last.

The invention relates to a method for optimizing electricity network output power in the technical field of electrical engineering, comprising the following steps: calling real-time data and net rack basic parameters of an SCADA database to form tidal data cross-section files; then calling load prediction system data and obtaining load growth mode of the next stage; converting the format of the tidal data cross-section files and the load prediction data to generate output mode optimized format data of the exertion mode of the generator; then carrying out optimization process on the exertion mode of the generator and outputting an optimum proposal; formulating an exertion plan of the generator according to the optimum proposal and implementing the generation exertion mode plan. In the invention, with the optimum proposal of the invention, the purpose of fast and effectively improving transmittable capacity of the power system and strengthening stability level of network voltage can be achieved for the power system transmission.

The invention relates to a wind power magnetic suspension yaw motor control method based on model predictive control and belongs to the technical field of electrical engineering. According to the method, the model predictive control technology is used, and the suspension and yaw rotation processes of a magnetic suspension yaw motor is smoothly controlled in real time. When a wind direction changesand yaw is needed, firstly a rotor current converter finds an optimal control law through a cost function to control the current of a rotor, thus the rotor is suspended upwards and is maintained at asuspension equilibrium point, secondly a stator converter finds an optimal control law through a cost function to control the current of a stator, thus the yaw motor rotates to a wind position according to a specified rotation speed, at the same time the rotor converter finds an optimal control law through a cost function to control the current of a rotor, thus the rotor is maintained at the suspension equilibrium point, the coordinated control of the stator and the rotor can be realized without decoupling, the fast tracking ability and stability of a system are ensured, at the same time, theinfluence of external disturbance on system operation can be effectively suppressed, and the system performance in an entire suspension yaw rotation process is optimal in real time.

The invention belongs to the technical field of electric engineering, and relates to a parallel storage battery pack voltage difference control technology. When storage battery packs run in a parallel mode, the charging voltage and the discharging voltage of each storage battery pack are controlled to enable the parallel storage battery packs to work in a health state; differential charging and discharging of the parallel battery packs can be achieved according to needs, and during the differential charging and discharging processes, the performance parameters and the state of the battery packs are detected; therefore, the performance of the parallel battery packs is improved, the service life of the parallel battery packs is prolonged, the flexibility of state detection of the parallel battery packs is improved, and the technical foundation is established for saving the operation cost of the parallel battery packs and improving economical benefits.

The invention belongs to the technical field of electrical engineering, and discloses a high-performance electrical engineering distribution circuit breaker. The high-performance electrical engineering distribution circuit breaker comprises a cabinet body, wherein a plurality of binding posts are arranged on the cabinet body, the plurality of binding posts are each connected with a conductive block, a motor is mounted inside the cabinet body, the motor is connected with a disc, one side of the disc is provided with a cylinder body, the disc is eccentrically hinged with a rocker, the rocker ishinged with a connecting rod horizontally extending into the cylinder body, the cylinder body is internally provided with a first piston fixedly connected with the connecting rod, and the cylinder body is provided with an air outlet; a fixed plate is fixed to the cabinet body, an airbag is arranged on the fixed plate, an air inlet hole is formed in the airbag, and the air inlet hole is connected with the air outlet by means of an air pipe; and an insulating plate is fixed to the cabinet body, a through hole is formed in the insulating plate, an insulating rod penetrates the through hole, the insulating rod is connected with a conductive plate, and the conductive plate is used for conducting the conductive blocks when the airbag jack up the insulating rods due to inflation. The high-performance electrical engineering distribution circuit breaker can solve the problem of difficult heat dissipation inside a circuit breaker when the circuit breaker is working.

The invention discloses a moistureproof insulation material for electrical engineering. The material comprises an inner layer and an outer layer. The inner layer is prepared from the following raw materials in parts by weight: 10-16 parts of quartz sand, 16-22 parts of aluminum oxide, 16-22 parts of polyallylamine resin, 3-9 parts of dimethylformamide, 1-4 parts of butyl rubber and 3-9 parts of nano silicon dioxide. The outer layer is prepared from the following raw materials in parts by weight: 15-22 parts of epoxy resin, 10-17 parts of polyamide resin, 20-28 parts of glass fiber, 2-6 parts of ethylene propylene diene monomer rubber, 0.5-1.2 parts of 2-mercaptobenzimidazole, 1-4 parts of nano zinc oxide, 10-18 parts of silicon nitride, 2-9 parts of hydrogenated nitrile-butadiene rubber, 5-11 parts of aluminum nitride and 5-11 parts of polyethylene. The moistureproof insulation material is composed of the inner layer and outer layer; the outer layer achieves the moistureproof effect under the combined actions of the components; and the material has steady insulating property under the combined actions of the components of the inner layer.

The invention provides an interactive and smart electric energy distribution and consumption monitoring device and method, and belongs to the technical field of electric engineering. An Anybus Profinet AB7013 webmaster is used for breaking through limit of the line distribution length and the communication bottleneck that one through network is hard to realize, the operating condition of a detected device is flexibly detected, start and stop of an operating device are controlled, an electrical load for alarming is omitted, and the electric energy waste condition due to abnormal operation of the electrical load is avoided; for the detected device, different device types and different regional devices can be involved, and the requirement for distributed smart data collection can be met; by means of a terminal user energy-saving monitoring, analysis and optimization technology, comprehensive energy conservation of multiple building groups and multiple districts can be achieved, and energy efficiency is improved; collected user requirement data are stored in an upper computer in a report mode, mangers can conveniently check the data regularly, energy conservation and consumption reduction in the electrical industry are guaranteed, and operation is safe and efficient.

The invention discloses a control method and system for primary frequency modulation of a wind storage system, and belongs to the technical field of electrical engineering. The system comprises bottom-layer doubly-fed induction generator DFIG vector control, energy storage system ESS double closed-loop control, upper-layer power consistency control and state of charge (SoC) consistency control. Normal operation of the fan and the energy storage system is guaranteed through bottom-layer control, and power distribution of the fan and the energy storage system is adjusted through upper-layer control; on the basis of power consistency control, energy storage equipment can adjust energy storage frequency modulation power output in real time according to different capacities of the energy storage equipment; reference power of the DFIG network side converter is adjusted based on an SoC consistency protocol, and output of all energy storage devices is adjusted according to the SoC on the premise that the energy storage devices are charged and discharged at the same time. Thus, the wind storage output power can be effectively adjusted in real time to stabilize the frequency, and stable operation of the wind power plant is guaranteed.

The invention relates to an electric engineering technology, in particular to an incremental multitarget layering dynamic reactive power control method for a regional power grid. In the incremental multitarget layering dynamic reactive power control method for the regional power grid, acquisition, analysis, calculation and control of data are finished by using a reactive power control data interaction module, an increment control module which considers load fluctuation, a multitarget layering reactive power control strategy generation module and an emergency response strategy module. By usingthe powerful data acquisition and management capability of a regional power grid energy management system of a power system, the required data is directly read from the regional power grid energy management system; and by using the conventional system, hardware investment is saved; an incremental reactive power control scheme can effectively adapt to an actual transformation situation of network load; and a layering strategy generation mechanism can effectively simplify the calculation complexity.

The invention discloses a self-power direct current solid state circuit breaker based on a normal open type SiC device, belonging to the electrical equipment and electrical engineering technical field, and comprises a normal open type SiC power switch tube, a negative pressure turn-off circuit and an absorption circuit. The circuit breaker is characterized by employing the normal open type SiC power switch tube, and realizing overcurrent protection by detecting the drain-source voltage of the power switch tube; and utilizing the drain-source voltage under a fault state as the input power source of the negative pressure turn-off circuit, and realizing the self-power of the circuit breaker. Compared with a traditional solid state circuit breaker, the solid state circuit breaker of the invention does not need complex functional circuits such as a current detection device, a signal conditioning circuit and an auxiliary source circuit, thereby reducing the loss of the solid state circuit breaker, and increasing the response speed of the solid state circuit breaker.

The invention discloses a multi-inverter speed adjusting system of a low-voltage high-power multi-branch alternating current (AC) motor and pertains to the technical field of electrical engineering and relates to the electric transmission and the motor control of large machinery equipment. The system comprises a low-voltage high-power AC motor and at least two frequency converters, wherein, the low-voltage high-power multi-branch AC motor combines output ends of windings of a plurality of branches in parallel connection to form at least two three-phase output terminal groups each of which is connected with the frequency converters. Each three-phase output terminal group of the low-voltage high-power AC motor and the general low-voltage frequency converter connected with the motor form a separate circuit, thus avoiding the disadvantages of a driving system in which a high-voltage frequency converter supplies power to a high-voltage asynchronous motor. In addition, the general low-voltage frequency converter can adopt an SPWM control method with good output voltage waveforms and meanwhile, the price of the frequency converter is reduced and the reliability of the operation of the frequency converter is guaranteed.

The invention discloses an adaptive damping control method for a wind power grid-connected system based on multiple convex polytopic bodies, and belongs to the technical field of electrical engineering. According to the method, firstly, a multi-objective robust controller is designed for a single convex polytopic body, secondly, a classification decision tree is constructed and trained with a large amount of offline data, a regression decision tree is established by using online wide-area data, and a convex polytopic body area to which a current operation point belongs is identified, and finally, a robust controller corresponding to the convex polytopic body is adaptively switched in real time according to an online decision mechanism. According to the method, when wind power output has awide range of random fluctuations, the random drift behavior of a system operating point can be effectively tracked, thus the adaptive damping control is implemented, and system oscillation is effectively damped.

The invention relates to a wind power magnetic suspension yaw system suspension control method based on a model mismatch compensator and belongs to the technical field of electric engineering. According to the method, by means of combination of model prediction control, PID and a model mismatch device, the problem of deviation caused by model mismatch due to linearized processing close to a magnetic suspension yaw system balance point is solved, and suspension at the balance point is controlled stably in real time; a model prediction control strategy is adopted according to a linearized model,a suspension air gap controller is designed, and outer ring suspension air gap control is achieved; output of the suspension air gap controller and output of the model mismatch device are added, a current measurement value of a suspension electromagnet winding is subtracted, a PID controller controls currents of the winding, and inner ring current tracking control is achieved; and suspension airgap deviation and winding current deviation are multiplied by respective adjusting parameters and then added to form the model mismatch device. The method is high in control precision, can effectivelysuppress the influence of external disturbance, and ensure that suspension close to the balance point is fast and stable.

The invention discloses a portable workbench for electrical engineering. The portable workbench comprises a cuboid box body of which the top is provided with an opening, a hydraulic lifting rod is arranged on the inner bottom surface of the box body, a cuboid table surface connected with the inner side wall of the box body in a sliding manner is arranged at the top of the hydraulic lifting rod, an illuminating lamp is arranged at the position, close to one of short edges, on the upper surface of the table surface through an universal pipe, a mounting clamp is arranged at the position, close to the other of short edges, on the upper surface of the table surface through a support, supporting seats are symmetrically arranged in the middle of the upper surface of the table surface, a hydraulic oil cylinder is arranged on each supporting seat, piston rod ends of the hydraulic oil cylinders are oppositely arranged, a baffle plate is arranged at the piston rod end of each hydraulic oil cylinder, and the inner bottom surface of the box body is further provided with a lifting motor for driving the hydraulic lifting rod to lift, a telescopic motor for driving the piston rod ends of the hydraulic oil cylinders to expand and a storage battery. The workbench is finer in structure, and can be portable.

The invention belongs to the technical field of genetic engineering technologies, and in particular relates to a quantitative catalyst preparation device for genetic engineering experiments. The invention aims at providing a quantitative catalyst preparation device, which is time-saving and labor-saving, good in catalytic effect of a prepared catalyst and good in safety, and is capable of quantitatively blending catalyst raw materials and water, for genetic engineering experiments. In order to achieve the aim, the invention provides the quantitative catalyst preparation device for the genetic engineering experiments, which comprises a bottom plate, a left side plate, a first sliding rail, a compression cylinder, a right side plate, a first sliding block, a rack, a connecting rod, a piston, a motor, a first rotating shaft, a driving wheel, a gear, and the like, wherein the left side plate, the first sliding rail, the compression cylinder and the right side plate are sequentially arranged on the top of the bottom plate from left to right. The quantitative catalyst preparation device can realize the processes of stirring and adding water during the preparation of the catalyst by using one electrical device, i.e., the motor, and simultaneously enables the catalyst to be prepared in a closed box.

The invention discloses a new energy uncertain set modeling method based on spatial-temporal correlation, and belongs to the technical field of electrical engineering. The method comprises the following steps of firstly, collecting historical data of all new energy field station output, wherein historical data of each day is a historical scene; then solving a minimum closed-package high-dimensional ellipsoid capable of surrounding all historical scenes; selecting a plurality of vertexes of the ellipsoid as the top points of the uncertain set, namely, obtaining the expression of the generalizedpolyhedron defined by the vertexes to describe the uncertain set, and finally introducing a zooming coefficient modification uncertain set. According to the method, a new uncertain set is formed by convex hulls surrounded by limit scenes of a limited number, and can be easily expanded to the existing two-stage robust optimization method. The number of the limit scenes and the number of the randomvariables are linearly increased, and the solving speed of the robust optimization method is guaranteed. The method has the advantages that the economy of the set can be adjusted by modifying coefficient according to the actual demand.