320results about How to "Good practical engineering application value" patented technology

The invention relates to a soil slope water flow erosion resistance simulation test method and device. The device comprises a liftable slope simulation device, a sheetflood scouring simulation device, a water and soil collecting device, a flow velocity determining device and a slope surface form camera device. According to the test method, the water flow is controlled, surface flow and seepage are formed, and sheetflood water, seepage water and sediment quantity formed by scouring slopes by sheetflood water are collected. The flow, the flow velocity, the erosion depth, the sand yield and the like of the water flow are measured quantitatively. Compacted soil is soaked in water until saturation for simulation, the efficiency of an indoor simulation test on slope scouring is improved, the test period is shortened, the test result proves the maximum depth of a slope erosion gully and the change rule of the sand yield with time, discloses the relation between the water flow erosion capacity of catchment behind slopes and the slope length, gradient and time and provides a basis for prediction of the water flow erosion scale and the need of slope protection and reinforcement. The device is simple in structure, convenient to operate and suitable for measurement of soil mechanics parameters of slope soil mass.

The invention discloses a tri-pole direct current transmission system topology structure based on an MMC. The tri-pole direct current transmission system topology structure is characterized in that direct current transmission is performed in a tri-pole connecting mode, and each pole comprises a rectification-side converter transformer, a rectification-side converter, a rectification-side smoothing reactor, a direct current transmission line, an inversion-side smoothing reactor, an inversion-side converter and an inversion-side converter transformer group. The rectification-side converters and the inversion-side converters are in modular multi-level structures, sub-modules of different amounts are connected in series and in parallel to be adapted to requirements for different voltage classes and currents, and three transmission lines used in a tri-pole direct current system are cables or overhead lines. The tri-pole direct current transmission system topology structure is high in reliability and capable of meeting the requirement for changing alternating current lines into direct current lines, phase change failures on the inversion side can be avoided under the condition that an alternating current system breaks down, voltages on two sides of the alternating current system can be stabilized, a alternating current filtering and reactive compensation device is not needed, and good application values are provided.

A method for detecting radar mobile object of single channel synthetic hole diameter based on multivision sub image pair includes forming multiple symmetric sub image pairs by multivision image of synthetic hole diameter radar data, forming each sub image pair by two subvision images, utilizing subvision image cancellation to accumulate cancellation result by two - dimensional united means along position and distance directions for effectively suppressing background clutter interference as well as for realizing energy accumulation of mobile object then applying constant false alarm technique to finalize detection on mobile object.

The invention belongs to the technical field of reliability engineering, and relates to an equipment residual service life prediction method under the condition of uncertain degradation measured data. The method includes the following steps: creating an equipment performance degradation model under the condition of the uncertain degradation measured data, estimating model parameters, estimating an equipment potential performance degradation state and predicating residual service life. The equipment residual service life prediction method under the condition of the uncertain degradation measured data is provided, degradation state uncertainty and measurement uncertainty are considered, characteristic quantity of individual service life and overall reliability service life of equipment are predicated and analyzed, and the method can serve as an effective analysis tool for predicating the residual service life of the equipment so as to provide powerful theoretical basis and technical support to state-based maintenance of the equipment, so that expenditure is reduced, unnecessary economic loss is avoided, and good engineering application value is realized.

The invention discloses a fault diagnosis method based on local mean decomposition (LMD), singular value decomposition (SVD) and an extreme learning machine (ELM), and aims to increase the accuracy of bearing fault diagnosis under a variable condition. The method comprises the following steps: firstly, decomposing a nonlinear and unstable original vibration signal into a series of product functions (PFs) by adopting an efficient adaptive signal processing method LMD, wherein each PF component is a product of an envelope signal and a pure frequency modulated signal having physical meaning; secondly, processing the PF components by adopting the SVD to compress a feature vector scale and obtain a more stable feature vector value; lastly, classifying a bearing fault state by applying the ELM having higher application computation efficiency and higher classification accuracy based on an extracted feature vector. By adopting the fault diagnosis method based on LMD-SVD-ELM, a set of complete and valid variable-condition fault diagnosis scheme is provided for a bearing. The method has a very good practical engineering application value.

The invention relates to a degradation modeling-based equipment failure number prediction method. Performance degradation data obtained by a product during a performance changing process is fully utilized to predict the residual life of the single high-reliability product; a failure number of the equipment is determined; and spare part management is optimized based on the prediction of the failure number of the equipment. The method comprises the following four steps: establishing a performance degradation model of the equipment; carrying out parameter estimation in the performance degradation model; carrying out residual life prediction; and carrying out equipment failure number prediction. Compared with the prior art, the provided method enables prediction parsing to be carried out on the individual residual lift and the general reliability service life of the product; and the provided method can be used as an effective analytic tool for predicting the product residual life and the failure number. And a powerful theoretical basis and technical support can be provided for product maintenance and spare parts ordering strategy determination. Therefore, the expenditure can be saved and unnecessary economic loss can be avoided. And thus the method has the great engineering application value.

The invention discloses a power distribution network flow computing method based on equivalent node injecting current transformation. The method comprises the steps that firstly based on a traditional fundamental principle of a Newton-Raphson method, the equivalent node injecting current transformation is adopted, a non-linear flow equation which corresponds to PG nodes in a power distribution network is transformed into a linear equation, accordingly a Jacobian matrix in a flow iteration calculation formula can be simplified, most elements of the matrix are enabled to be constants, repeated calculation is not needed, and calculated amount is reduced; then the Jacobian matrix is calculated through a sparse technology, memory space is greatly saved, and calculation speed and efficiency of an algorithm are improved; finally, accuracy and effectiveness of the algorithm can be verified through test cases. In addition, through compassion of calculation performance of different algorithms, the computing method has the advantages of being high in calculation speed, high in calculation efficiency, good in convergence property and strong in looped network processing capacity.

The invention discloses a meshless RKPM-based two-dimensional thermal deformation and stress analysis method for an anisotropic material structure. The method mainly comprises the following steps of (1) performing RKPM node discrete preprocessing on a calculation model; (2) solving an RKPM thermal deformation displacement value: assembling RKPM overall force stiffness matrix and overall thermal load column vector; applying a boundary, and processing a first boundary condition by adopting a penalty function method; establishing a meshless RKPM thermal stress discrete control equation of the anisotropic material structure, and solving the RKPM thermal deformation displacement parameter value of a node; (3) solving an RKPM thermal stress value: performing approximation on the obtained thermaldeformation displacement parameter value by adopting reproducing kernel approximation to calculate out a thermal stress of a Gaussian point, thereby obtaining the RKPM thermal stress value of the node; and (4) post-processing a calculation result. The two-dimensional thermal deformation and stress analysis of the anisotropic material structure is performed based on a meshless RKPM; and a numerical method is stable and high in precision.

The invention relates to an energy storage system operation optimization control method for prolonging the service life of a lithium battery. The energy storage system operation optimization control method is characterized by including the steps of according to experimental data of the maximum charging-discharging circulation time number of an energy storage battery under different charging-discharging depths, defining the charging-discharging circulation depth corresponding to the time when the maximum electric quantity can be handled under the different charging-discharging circulation depths in the service life cycle of the battery to be the standard charging-discharging circulation depth of the battery, and building a service life attenuation degree evaluation index of the battery under frequent and random charging-discharging occasions according to the degree of the battery operating charging-discharging circulation depth deviated from the standard charging-discharging depth. If a single battery energy storage system is used for completing the task of stabilizing contribution fluctuations, due to the randomness of wind power contributions and photovoltaic contributions, the battery operating charging-discharging circulation depth can not reach the standard charging-discharging depth. Based on the fact, the dual-battery energy storage unit main circuit structure and the coordination control strategy are designed, battery units are allowed to operate under the standard charging-discharging depth, and the energy storage life of the battery is prolonged to the maximum degree.

The invention discloses a hydraulic pump fault diagnosing method based on local mean decomposition (LMD), singular value decomposition (SVD) and information-geometric support vector machine (IG-SVM) so as to improve fault diagnosing accuracy in the case of small samples. The LMD, serving as a self-adaptive signal processing method, can decompose original vibration signals of a hydraulic pump into a limited number of signal components in a self-adaptive mode; then, the signal components are processed through the SVD, the data size of the signal components is compressed, and simpler and more stable fault feature vectors are extracted; finally, the fault states of the hydraulic pump are classified through the IG-SVM, and the fault diagnosing accuracy in the case of the small samples is improved. By the adoption of the fault diagnosing method based on the LMD-SVD-IG-SVM, a complete and effective fault diagnosing scheme in the case of the small samples is provided for the hydraulic pump, and the method has good actual engineering application value.

The invention discloses a method for designing a novel mesh antenna structure with a shaped pattern. The method comprises the steps of conducting shape design on a reflective surface of an antenna cable net firstly; then designing the cable net structures of an upper layer and a lower layer according to the shaped meshed reflective surface, so that an overall three-layer cable net structure is obtained; conducting pretension balancing design on the three-layer cable net structure so as to guarantee the tensile property and realizability of the structure; designing a three-layer truss structure supporting the three-layer cable net finally, so that a cable net-truss overall antenna structure is obtained. By extending a two-layer cable net structure of a peripheral truss type extendable mesh antenna into the three-layer cable net structure, the mesh antenna structure with the shaped reflective surface is obtained, and the design process is simple; the designed shaped mesh antenna structure is tensile, easy to realize and high in engineering application value.

The invention relates to a power supply recovery method of a power distribution network comprising distributed power supplies after a fault. The power supply recovery method is technically characterized by comprising the following steps of (1) splitting the distributed power supply which does not have isolated island operation capability after a large-area power failure condition is caused by the fault of the power distribution network; (2) carrying out isolated island division by using a searching method on the basis of the principle that the distributed power supplies run with surrounding loads, and then enabling an isolated land, with the surrounding load, of the distributed power supply with the isolated island operation capability to run; (3) isolating a fault point and recovering power supply of the remaining sound network; and (4) enabling the distributed power supply or isolated island with a grid-connection condition to run in a grid-connection manner and enabling the isolated land without the grid-connection condition to further run. The effects of the distributed power supplies can be fully developed under the premise of recovering load power supply as much as possible; the important load power supply reliability is improved; meanwhile, the switching action frequency is reduced as few as possible in the power supply recovery process; and the network loss is reduced as much as possible after power supply recovery.

The invention relates to a cutter damage real-time monitoring method based on spindle vibration feature fusion. The method comprises the steps that firstly, for a milling process, a cutter damage process is analyzed, a cutting layer thickness calculation model considering cutter eccentricity and damage is established, milling force calculation is carried out, and milling force time domain and frequency domain characteristics are analyzed; experimental testing and modal parameter identification are conducted on a tool nose point-spindle head transfer function, spindle vibration response under an excitation effect of milling force is calculated, and time domain and frequency domain characteristics of the vibration response are analyzed; frequency domain amplitudes of spindle vibration displacement responses in the X direction and the Y direction are fused, and a cutter damage characteristic is defined; and real-time data acquisition, dynamic extraction and splicing are carried out on a spindle vibration acceleration signal, a cutter damage characteristic value is calculated, and the cutter damage characteristic value is compared with a threshold value to judge whether a cutter is damaged or not in real time. According to the method, rapid and accurate cutter damage monitoring can be realized, and an implementation scheme is simple and effective.

The invention discloses a prefabricated steel reinforced concrete beam with a transversal high-strength concrete clapboard. The prefabricated steel reinforced concrete beam with the transversal high-strength concrete clapboard is composed of a prefabricated part and a cast-in-situ part according to the thought of partially prefabricating and partially casting in situ. The prefabricated steel reinforced concrete beam with the transversal high-strength concrete clapboard comprises a prefabricated U-shaped high-strength concrete groove, cast-in-situ common concrete I filled in the prefabricated U-shaped high-strength concrete groove, sectional steel arranged in the length direction in the prefabricated U-shaped high-strength concrete groove and parallel to the length direction of the groove, a transversal high-strength concrete clapboard arranged in the prefabricated U-shaped high-strength concrete groove and vertical to the length direction of the groove, a plurality of closed stirrups arranged in the prefabricated U-shaped high-strength concrete groove and vertical to the length direction of the groove, a longitudinal bar I arranged at the bottom of the prefabricated U-shaped high-strength concrete groove and parallel to the length direction of the groove, and a cast-in-situ flange plate arranged at the top of the prefabricated U-shaped high-strength concrete groove. The prefabricated steel reinforced concrete beam with the transversal high-strength concrete clapboard, disclosed by the invention, is capable of increasing the longitudinal anti-shear action between prefabricated concrete and cast-in-situ concrete, preventing lateral breakages, and improving the cracking resistance, durability and fire resistance of the beam.

The invention discloses a microgrid power flow calculation method based on a full-pure function, and the method comprises the steps: 1) constructing the full-pure function of a balance node, a PQ nodeand a PV node, and obtaining a microgrid power flow model based on a node full-pure function equation; 2) recursively solving a full-pure function equation of the microgrid node based on equivalent Maxlalin series expansion of a full-pure function to obtain coefficients of full-pure function Maxlalin series expansion of the PQ node, PV node voltage and PV node injection reactive power; and 3) constructing a solved Pade approximation formula of the unknown variable full-pure function Maxlalin series expansion of the microgrid to obtain a feasible microgrid power flow solution. According to themethod, non-iterative recursive solution is adopted, an initial value of an unknown variable does not need to be set, a Jacobian matrix does not need to be solved, whether a power flow solution exists in the system or not can be judged, a feasible solution can be solved under the condition that the power flow solution exists, a calculation result has great guiding significance in planning designand operation control of the microgrid, and the method has very high engineering application value.

The invention discloses an electromechanical-integration-based shaped beam design method for a satellite-borne mesh antenna. In the method, firstly, an electromechanical-integration-based shaped design optimization model for the mesh antenna is built, the force density of a cable net serves as the design variable of the optimization model directly, and under the condition that the cable net is in a tensioned and balanced state without loose cables, the method aims to achieve the targets of enabling the electrical performance of a far field to meet the shaping requirement as far as possible and making the tension of the cable net uniform as far as possible; then, iterative solving is performed on the optimization model till the optimal comprehensive target of the electrical performance and the tension uniformity is achieved, and shaped beam design of the mesh antenna is completed.

The invention discloses an instantaneous rotational frequency estimation method based on ridge line probability distribution and local fluctuation characteristics and a detection device thereof. The method comprises the flowing steps that: a low-frequency region is separated from a vibration signal and a resonance frequency band is identified by using a fast spectral kurtosis method to realize frequency band separation, and time-frequency distribution characteristics of the signal low-frequency region and the resonance frequency band are enhanced based on an amplitude accumulation square algorithm; rotational frequency synchronization ridge lines of the signal low-frequency region and the resonance frequency band are searched respectively by using a peak searching algorithm and rotational frequency information is obtained by pre estimation, and then the resonance frequency band is synchronized; with a probability-distribution-based abnormal ridge line zone positioning method, a ridge line failure position is determined to improve a result of fusion of ridge lines obtained by extraction on low-frequency band and resonance envelope signals; and an abnormal zone fusion criterion based on local fluctuation characteristics is established and a standard deviation is introduced as a statistical indicator to indicate the fluctuation characteristic of the ridge line, and a fusion result is evaluated by using the standard deviation as an abnormal data segment fusion indicator to realize accurate rotational frequency estimation.

The present invention relates to a magnetic control memristor type Lv system hyperchaotic hidden attractor generation circuit and a construction method thereof. The hyperchaotic hidden attractor generation circuit includes an oscillation system and an equivalent realization circuit corresponding to a magnetic control memristor; and the oscillation system is connected with the equivalent realization circuit so as to present a corresponding hidden oscillation phenomenon. According to the magnetic control memristor type Lv system hyperchaotic hidden attractor generation circuit and the construction method thereof of the invention, a magnetic control memristor term, namely, a first integral channel, is added into the first equation of an original Lv system; a linear feedback term and external excitation, namely a second integral channel, is added into the second equation of the original Lv system; and a third second integral channel is kept constant; and therefore, the hyperchaotic hidden attractor generation circuit can be generated.

The invention discloses a heuristic gain adaptive PID control method for a complex nonlinear pumped storage power unit speed regulating system. First, a heuristic gain adaptive PID controller is set up based on a simple and practical parallel PID control structure; then, a fine model of a nonlinear pumped storage power unit speed regulating system is constructed; next, a multi-objective function of nonlinear pumped storage power unit speed regulating system HGS-NPID control parameter optimization is built; and finally, nonlinear pumped storage power unit speed regulating system HGS-NPID control parameters are optimized using a multi-objective artificial sheep flock algorithm. The heuristic gain adaptive PID control method for a nonlinear pumped storage power unit speed regulating system presented by the invention is simple to implement, and has strong real-time performance. The control gain can be adjusted online and adaptively according to the change of the operating point. The method fully adapts to the hydraulic shock and nonlinearity of the pumped storage power unit speed regulating system, and can improve the dynamic quality of the conventional control method under different working conditions of a water head.

The invention discloses a low-speed impact locating method for a composite material cell structure, and belongs to the field of composite material structure engineering structure health monitoring. According to the method, an unconstrained optimization algorithm based on a Newton method is applied to solving the low-speed impact recognition problem of the composite material cell structure, and the low-speed impact fast recognition of the structure is achieved. Based on a sensor array technology, impact induction is applied to the structure to generate Lamb wave signals, and impact response signals of the composite material cell structure are collected. A certain sensor is used as the criterion, the wavelet analysis means is adopted, and the time differences of Lamb waves reaching the other sensors are extracted. The unconstrained optimization algorithm based on the Newton method is adopted to solve and locate a system of nonlinear equations, and therefore the position of an impact source is obtained. The impact source of the composite material cell structure can be recognized fast and effectively, recognition precision is high, and good engineering application value is achieved.

The invention discloses a hybrid series-parallel full-bridge circuit applicable to high-voltage or high-current output, and belongs to the field of power electronics conversion. The hybrid series-parallel full-bridge circuit consists of m full-bridge conversion units, the input sides of which are connected in parallel and the output sides of which are connected in series/in parallel; m is greater than or equal to 2; when the output sides are connected in series, the hybrid series-parallel full-bridge circuit is applicable to a high-voltage output occasion; and when the output sides are connected in parallel, the hybrid series-parallel full-bridge circuit is applicable to a high-current output occasion. The invention further discloses a control method for the hybrid series-parallel full-bridge circuit applicable to high-voltage or high-current output. All the full-bridge conversion units of the hybrid series-parallel full-bridge circuit have self voltage/current sharing capacity, so that all transformers and output rectification and filtration parts in the full-bridge conversion units are forced to share voltage/current; the circuit structure is high in expansion capacity; the hybrid series-parallel full-bridge circuit is applicable to an application occasion with high-voltage or high-current output, and is high in engineering application value.

The invention discloses a method for calculate continuous power flow of AC/DC hybrid micro-grid include such steps as forming two types of AC/DC hybrid micro-grid operation system and nine types of node, adopting LM (Levenberg-Marquardt with a nonmonotone line search (LMNL) algorithm and alternating iterative method based on LMNL algorithm are used to solve the initial point of continuous power flow of AC/DC microgrid subsystem and AC/DC interconnected microgrid respectively. A two-way iterative predictive correction method combining tangent prediction and combined Newton correction is used topredict and correct the AC/DC interconnected microgrid. The conventional power flow calculation method based on LMNL algorithm proposed in this paper is applicable to the conventional power flow calculation of different types of microgrids. The proposed two-way iterative prediction and correction method solves the complex and diverse problem of AC/DC power coupling and continuous power flow calculation under different AC and DC loads. The method of the invention is applicable to continuous power flow calculation of AC/DC hybrid microgrid under various operation modes, and has good engineeringapplication value.