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31 results about "Nonlinear differential equations" patented technology

A linear differential equation is a differential equation (an equation containing a function and its derivatives) where the function and its derivatives: Hence, a nonlinear differential equation is any one that violates any of those two conditions.

BWBN model-based bridge pier nonlinear earthquake random response analysis method

PendingCN120706186AGeometric CADVirtual/augmented realityAlgorithmEquivalent linearization
The invention provides a bridge pier nonlinear earthquake random response analysis method based on a BWBN model, and belongs to the field of civil engineering structure random vibration analys.The method comprises the steps that discretization processing is conducted on a concrete bridge pier structure, and a finite element nonlinear analysis numerical model is constructed; constructing a BWBN model by combining linear and nonlinear differential equations, setting a hysteresis parameter value of the BWBN model, simulating by adopting an Euler-Bernoulli beam unit, and establishing a degraded beam finite element model; obtaining a unit hysteresis vector, constructing a system motion balance equation, solving an equivalent linearization coefficient, constructing a covariance matrix of random response of the concrete pier structure, performing random response analysis on the concrete pier structure, and exploring typical working conditions of random excitation. According to the method, the operation time is shortened, the calculation precision is improved, and meanwhile, the response characteristics of the reinforced concrete pier structure under nonlinear earthquake random excitation can be truly represented.
Owner:BEIJING JIAOTONG UNIV

Transient stability analysis method for hybrid synchronous control network-forming inverter considering damping influence

The invention discloses a method for analyzing transient stability of a hybrid synchronous control grid-forming inverter considering damping influence, and belongs to the field of DC / AC converters, the method comprises the following steps: dividing a power angle interval to be analyzed into a plurality of sub-intervals, constructing an explicit damping-power angle function in each sub-interval, further quantifying the damping influence, and calculating the transient stability of the hybrid synchronous control grid-forming inverter. And depicting a transient stability boundary of the network-constructing inverter system. According to the method, the damping influence is quantified, the defect that a traditional equal-area method is too conservative is overcome, meanwhile, compared with a traditional transient stability analysis method needing iteration, the method does not need to solve a nonlinear differential equation through complex numerical iteration, an explicit transient stability boundary can be obtained, and the method is suitable for being used for transient stability analysis. And the method is also used for the grid-forming inverter with droop control and virtual synchronous machine control of a linear damping item, and an effective method with high analyzability and low complexity is provided for transient stability analysis of the grid-forming inverter. And the method has good practical application value.
Owner:HUAZHONG UNIV OF SCI & TECH

Equivalent taper correction calculation method and system based on wheel rail profile data

The invention provides an equivalent taper correction calculation method and system based on wheel rail profile data, and relates to the technical field of motor train unit application and maintenance, and the method comprises the steps: collecting profile coordinate data of wheels, wheel diameters and distance measurement in wheel pairs through machine tool measurement equipment, and obtaining standard rail profile coordinate data and a rail gauge according to the type of a steel rail; carrying out secondary interpolation and smoothing processing on the wheel rail profile coordinates by adopting a spline function to generate wheel rail profile data; the equivalent taper is calculated through a nonlinear differential equation integral algorithm, and a relation curve of the equivalent taper and the transverse movement amount is finally solved; interpolation processing is conducted on the relation curve of the equivalent taper and the transverse movement amount, final correction is conducted on the nominal equivalent taper through an origin symmetry correction algorithm, and a corrected equivalent taper value is obtained. The method has the beneficial effects that the measurement precision of the equivalent taper is improved, the wheel turning repair strategy is optimized, the operation safety and stability of the motor train unit are guaranteed, and the maintenance cost is reduced.
Owner:SOUTHWEST JIAOTONG UNIV

Offshore wind power flexible direct current grid-connected system safety assessment method based on accessibility analysis

The invention discloses a safety assessment method for an offshore wind power flexible direct current grid-connected system based on reachability analysis. The method comprises the following steps: constructing a high-dimensional nonlinear differential equation model and a nonlinear hybrid system model of the offshore wind power flexible direct current grid-connected system based on a Kron simplification method; constructing an uncertain variable model with a random change range by utilizing a sino polyhedron, and adding the uncertain variable model into the nonlinear hybrid system model as an uncertain input item; based on a reachability analysis theory, designing an improved reachability set calculation algorithm based on an adaptive time step optimization method, and dynamically balancing the calculation precision and the calculation efficiency of the reachability set by adjusting the time step; and an improved reachable set calculation algorithm is applied to calculate reachable set results of the offshore wind power flexible direct current grid-connected system under the influence of different operation conditions and uncertain factors. According to the method, the operation state of the offshore wind power flexible direct current grid-connected system can be subjected to safety evaluation according to the reachable set result, and important guidance is provided for guaranteeing safe and stable operation of the system.
Owner:SOUTH CHINA UNIV OF TECH

A network-configuration type converter transient power angle nonlinear mathematical analysis modeling method

The application discloses a kind of network type converter transient power angle nonlinear mathematical analysis modeling methods, this method is directed to the power system containing network type converter, lack of the mathematical analysis model of its transient power angle characteristic problem and proposes.The specific steps realized by the method are as follows: the system model of network type converter single-machine infinite system is constructed;Transient power angle nonlinear mathematical model of network type converter single-machine infinite system is established;Least square method is applied to fitting nonlinear differential equation;Transient power angle nonlinear differential equation after fitting is solved based on multiscale method.The application deduces the mathematical analysis model of network type converter transient power angle using circuit theorem, least square method and multiscale method, can predict the transient power angle response process of network type converter system in advance, compared with traditional phase diagram method, the mathematical analysis model can be analyzed network type converter transient power angle characteristic under different system parameters in large disturbance process.
Owner:SOUTHEAST UNIV

An asynchronous motor speed regulation method and system based on an improved super-twisting sliding mode algorithm

ActiveCN118300477BImprove robustnessSolve the speed problemMotor speedAlgorithm
This invention relates to the field of asynchronous motor control technology, specifically to an asynchronous motor speed control method and system based on an improved Super-Twisting sliding mode algorithm. The method includes: (1) deriving the fourth-order nonlinear differential equation of a three-phase squirrel-cage asynchronous motor in a rotating coordinate system d-q based on rotor magnetic field orientation theory; (2) designing a linear sliding surface based on the error between the set speed and the feedback speed; (3) using the first-order differential equation of rotor speed in step (1) and the linear sliding surface described in step (2), and introducing a variable proportional differential term based on the traditional Super-Twisting sliding mode algorithm to design a fast Super-Twisting sliding mode speed controller; (4) constructing a variable exponential switching function to replace the sign function in the fast Super-Twisting sliding mode speed controller described in step (3), thus completing the design of the improved Super-Twisting sliding mode speed controller. This solution effectively solves the problems of slow response speed and poor control accuracy in existing systems, thereby improving the overall robustness of asynchronous motor control.
Owner:WUXI XINJIE ELECTRICAL

Methods and related devices for establishing nonlinear mathematical models of hybrid DC transmission systems considering discontinuous characteristics

This invention provides a method and related apparatus for establishing a nonlinear mathematical model of a hybrid DC transmission system considering discontinuous characteristics. The method includes: representing the dynamic processes of discontinuous components in the main and control loops of the hybrid DC transmission system using a step function; approximating the step function as a continuous function using a linear combination of hyperbolic tangent functions to obtain a continuous expression; obtaining modular nonlinear differential equations for the rectifier, inverter, and AC / DC networks, and replacing the discontinuous dynamic parts involved in the equations with the continuous expression; and interconnecting the modules according to their input-output relationships to obtain a complete nonlinear mathematical model of the hybrid DC transmission system. This invention establishes a nonlinear mathematical model of a hybrid DC transmission system that accurately reflects discontinuous dynamic characteristics by employing the continuous approximation method using step functions and hyperbolic tangent functions, thereby improving the accuracy and practicality of system modeling.
Owner:ELECTRIC POWER RES INST CHINA SOUTHERN POWER GRID CO LTD +1

A method for constructing a curved surface solar concentrator with uniform light absorption on the surface of the absorber

PendingCN122286993Aevenly distributedEliminate local hot spotsPhotothermal conversionNonlinear differential equations
This invention relates to a method for constructing a curved solar concentrator with uniform light reception on the absorber surface, belonging to the field of solar photovoltaic and photothermal technology. This invention utilizes differential geometry theory to construct a system of first-order nonlinear differential equations relating the concentrator's reflective surface (x and y coordinates) to the radius r of the circular absorber. The reflective surface profile parameters are obtained through iterative solutions. A discrete point lattice is obtained, with the spatial straight-line distance and maximum deviation between adjacent iteration coordinate points not exceeding 2 mm as the convergence criterion. A curved concentrator model is then generated through spline curve fitting. The energy flux density distribution on the absorber surface is obtained using the ray tracing software Tracepro, and the uniformity of the energy flux distribution is verified using a relative deviation not exceeding ±10% of the average value. This invention achieves uniform distribution of incident solar radiation on the absorber surface, eliminates local hot spots, significantly reduces thermal stress gradients, and improves the photothermal conversion efficiency and operational stability of the solar concentrator system.
Owner:KUNMING UNIV OF SCI & TECH

Layered dynamic thermodynamic modeling method for salt cavern gas storage for compressed air energy storage

PendingCN121920274AGeometric CADDesign optimisation/simulationPower stationNonlinear differential equations
The invention provides a layered dynamic thermodynamic modeling method for a salt cavern gas storage for compressed air energy storage, and belongs to the technical field of compressed air energy storage. The core idea of the method is spatial discretization and layered solution, N control bodies are divided in the vertical direction according to the geometric characteristics of the salt cavern, then a mass conservation equation, an energy conservation equation and a Redl ich-Kwong real gas state equation are established for each control body, and finally all the control body equations are coupled into a nonlinear differential equation set. After initial conditions and boundary conditions are given, a numerical method is adopted for solving. According to the method, the temperature and pressure layering characteristics in the salt cavern can be accurately described, the problems that a traditional single-tank model underestimates the energy storage capacity and energy loss calculation is inaccurate are solved, high-precision model support is provided for compressed air energy storage power station power dispatching and system optimization, and high practicability and popularization value are achieved.
Owner:CHINA ENERGY CONSTR GRP TECH DEV CO LTD

Project management system and method based on smart park

The invention relates to the field of project management, and discloses a project management system and method based on a smart park, which are used for monitoring and dynamically adjusting a project management effect in real time and continuously improving the management effect. Comprising the following steps: extracting an event causal chain from a park historical event library, classifying and integrating according to energy, service and facility dimensions, and generating a causal atlas containing each sub-atlas; building a nonlinear differential equation model by using real-time data and the energy sub-atlas, simulating and predicting future energy flow, and outputting a time-sharing load prediction curve; based on the facility sub-atlas and the equipment topological graph, calculating a node critical probability, identifying key fragile nodes and generating a list; and dynamically generating a resource reinforcement and service transfer instruction set in combination with a real-time service request and load prediction to form a dynamic scheduling instruction. Precise, dynamic and intelligent park project management is realized, and the park operation efficiency and the resource utilization rate are effectively improved.
Owner:QINGDAO HOTEL MANAGEMENT VOCATIONAL & TECH COLLEGE

Elastic beam deformation analysis method and system based on fourth-order nonlinear differential equation

ActiveCN121093679BGeometric CADSustainable transportationNonlinear differential equationsNonlinear mechanics
This invention belongs to the field of mechanical analysis technology and provides a method and system for elastic beam deformation analysis based on fourth-order nonlinear differential equations. The method includes: obtaining the stress-strain relationship and lateral displacement function of the elastic beam; constructing a fourth-order nonlinear mechanical response function of the elastic beam based on the obtained stress-strain relationship and lateral displacement function; solving the constructed fourth-order nonlinear mechanical response function to identify the local buckling location and higher-order shear effects of the elastic beam; taking the minimum weight of the elastic beam as the objective function, considering the displacement and stress constraints of the elastic beam, performing sensitivity analysis of the elastic beam based on the obtained local buckling location and higher-order shear effects, adjusting the nonlinear coefficient of the elastic beam, and completing the elastic beam deformation analysis based on fourth-order nonlinear differential equations.
Owner:QINGDAO UNIV OF TECH

Efficient, universal and easy-to-use solution method for periodic response of high-dimensional complex nonlinear differential equation

PendingCN121958724AGeometric CADDesign optimisation/simulationAlgebraic equationNonlinear differential equations
The invention relates to a high-dimensional complex nonlinear differential equation periodic response efficient universal easy-to-use solving method, which is characterized in that an automatic differential technology and a harmonic balance method are fused, and the method comprises the following steps: step 1, solution setting: representing the periodic response of a system by using discrete Fourier series; step 2, harmonic balance: substituting periodic response in a Fourier series form of the system back to a system kinetic equation, and converting a differential equation into an algebraic equation through a harmonic balance program; 3, calculating a Jacobian matrix, namely, quickly obtaining an accurate Jacobian matrix of the algebraic equation after harmonic balance by utilizing an automatic differential technology; and 4, solving an algebraic equation, namely calculating by using a Newton-Raphson method to obtain a system periodic response. The method solves the problems that a high-dimensional complex nonlinear differential equation response solving method is low in efficiency, not universal and not easy to use, can be widely applied to calculation of high-dimensional complex nonlinear system dynamic response, and has the advantages of being efficient, universal, capable of being used immediately after being opened and modularized.
Owner:HARBIN INST OF TECH

A method for analyzing cross-scale interactions in power systems under transient disturbances

The present invention discloses a method for analyzing cross-scale interactions of power systems under transient disturbances, belonging to the field of power system control technology. A second-order Taylor expansion is performed at an off-equilibrium point on the nonlinear differential equations of the x-domain state variables of the power system under transient disturbances, so as to sequentially transform the nonlinear differential equations of the x-domain state variables into the y-domain, z-domain, and m-domain to obtain an analytical expression of the m-domain state variables. Compared to the first-order Taylor expansion, the second-order Taylor expansion includes a second-order nonlinear term matrix, which can more accurately characterize the strong nonlinear dynamic behavior of the power system. Furthermore, the analytical expression of the m-domain state variables is sequentially inversely transformed into the z-domain, y-domain, and x-domain to obtain an analytical expression of the x-domain state variables of the power system under transient disturbances. Since the analytical expression of the x-domain state variables includes a constant term, an independent frequency term, and a coupled frequency term, it describes the multi-time-scale characteristics of the power system at the off-equilibrium point.
Owner:HUAZHONG UNIV OF SCI & TECH

Quantitative Assessment Method for Wide Area Control System Cyber ​​Attacks Based on Reachability Analysis

ActiveCN118963128BAdaptive controlBiconjugate gradient stabilized methodWide area
The present invention discloses a quantitative assessment method for network attacks on wide-area control systems based on reachability analysis, comprising: establishing a nonlinear differential equation model of a wide-area control system with wind farm access based on a simplified admittance matrix; using Zeno polyhedrons to model the network attack amplitude range and the wind farm output variation range, respectively, and adding the established models to the nonlinear differential equation model of the wide-area control system; based on reachability analysis theory, improving the reachable set calculation algorithm using a Krylov subspace iteration method based on a stable biconjugate gradient method and zonotope bundle technology; applying the improved reachable set calculation algorithm to calculate the reachable set of the wide-area control system under the influence of different types of network attacks and wind power disturbances. The present invention quantitatively evaluates the damping performance of the wide-area control system under different network attack scenarios and operating conditions based on the reachable set results, providing important guidance for improving the damping performance of the wide-area controller and ensuring the safe and stable operation of the power system.
Owner:SOUTH CHINA UNIV OF TECH

Elastic beam deformation analysis method and system based on fourth-order nonlinear differential equation

ActiveCN121093679AGeometric CADSustainable transportationNonlinear differential equationsNonlinear mechanics
The invention belongs to the technical field of mechanical analysis, and provides an elastic beam deformation analysis method and system based on a fourth-order nonlinear differential equation, and the method comprises the steps: obtaining a stress-strain relation and a transverse displacement function of an elastic beam; constructing a fourth-order nonlinear mechanical response function of the elastic beam based on the obtained stress-strain relation and the transverse displacement function; solving the constructed fourth-order nonlinear mechanical response function, and identifying a local buckling position and a high-order shear effect of the elastic beam; taking the minimum weight of the elastic beam as a target function, considering the displacement constraint and stress constraint of the elastic beam, carrying out the sensitivity analysis of the elastic beam according to the obtained local buckling position and high-order shearing effect of the elastic beam, adjusting the nonlinear coefficient of the elastic beam, and completing the deformation analysis of the elastic beam based on the fourth-order nonlinear differential equation.
Owner:QINGDAO UNIV OF TECH

GFL-VSC transient stability analysis method and system considering LVRT control

The invention discloses a GFL-VSC transient stability analysis method and system considering LVRT control, and belongs to the technical field of power system safety and stability analysis. The method comprises the following steps: decomposing a full-order model into a low-order fast subsystem and a low-order slow subsystem by using small parameters based on a singular perturbation theory according to a time scale difference between a current loop and a phase-locked loop; in the slow subsystem, solving a nonlinear differential equation of a phase-locked loop by using a multi-scale method to obtain an approximate analytical solution based on initial conditions, system parameters and fault depth, and establishing a stable boundary criterion according to the approximate analytical solution; and in the fast subsystem, establishing a dynamic model comprising a time-varying item, solving to obtain an analytic solution of the dynamic model, and determining the transient stability of the GFL-VSC under the influence of the current loop control parameters according to the stability boundary criterion and the analytic solution. According to the method, the transient stability of the GFL-VSC considering the LVRT control can be effectively analyzed.
Owner:CHINA ELECTRIC POWER RESEARCH INSTITUTE CO LTD +1

Pan-tilt motor signal processing method and system, electronic equipment and storage medium

The invention provides a signal processing method and system of a pan-tilt motor, electronic equipment and a storage medium, and relates to the technical field of signal processing, a stator of the pan-tilt motor is provided with two linear Hall sensors, and the method comprises the following steps: respectively collecting Hall signals of the two linear Hall sensors; performing signal processing on the two Hall signals to obtain two Hall voltage signals; respectively carrying out noise extraction on the two Hall voltage signals based on a steepest control comprehensive function of a discrete system to obtain two standard voltage signals; and calculating the electrical angle of the pan-tilt motor according to the two standard voltage signals. Based on the steepest control comprehensive function of the discrete system, adaptive balance of noise suppression and phase lag is realized through the nonlinear differential equation, the electrical angle error of the pan-tilt motor is effectively reduced, the dynamic response speed of the pan-tilt motor system is improved, and the stability and real-time performance of a live broadcast picture are guaranteed.
Owner:MALANSHAN AUDIO & VIDEO LABORATORY

Single-cell developmental trajectory reconstruction method, device, electronic device and storage medium

ActiveCN116453598BBiostatisticsProteomicsAlgorithmNonlinear differential equations
The present invention provides a method, device, electronic device and storage medium for reconstructing the developmental trajectory of a single cell, which relates to the field of computer technology. The method includes: generating a gene regulatory network corresponding to the single cell based on a gene data set of the single cell; determining a differential equation corresponding to the gene regulatory network based on the gene regulatory network; determining a probability distribution corresponding to the gene regulatory network based on the differential equation; and establishing a potential energy topography map of the single cell based on the probability distribution. Through the above method, a nonlinear differential equation for reconstructing the developmental trajectory of a single cell is determined based on the gene regulatory network, and a probability distribution corresponding to the gene regulatory network is determined based on the differential equation. Based on the probability distribution, the developmental state of each cell of the single cell can be arranged in chronological order on the corresponding trajectory, thereby generating an intuitive potential energy topography map for reflecting the developmental trajectory of the single cell, thereby reconstructing the differentiation and developmental trajectory of the single cell in the tissue.
Owner:BEIJING YUANMA MEDICAL LAB CO LTD

Multi-core optical cable shape reconstruction method based on four-order step integration and GOC compensation

The invention discloses a multi-core optical cable shape reconstruction method based on fourth-order step integral and GOC compensation, and belongs to the technical field of structure health monitoring, and the technical key points are that the method comprises the steps: solving a curvature vector through the central wavelength change data of a fiber grating sensor in a multi-core optical cable; obtaining a geometric information matrix of the multi-core optical cable; constructing a multi-core optical cable shape reconstruction algorithm, carrying out numerical solution on a nonlinear differential equation of a tangent vector by adopting a four-order step integration method, substituting the obtained tangent vector into a geometric information matrix of the multi-core optical cable, and combining curvature information of the multi-core optical cable to obtain an ideal shape of the multi-core optical cable; and constructing a fiber core position geometrical optical compensation model, analyzing a geometrical relationship between an actual deviation fiber core position and a fiber core position of an ideal multi-core optical cable shape, and correcting a multi-core optical cable wavelength variation error caused by fiber core position deviation, so as to at least have the technical effect of improving the shape reconstruction precision of the multi-core optical cable.
Owner:NANJING UNIV OF AERONAUTICS & ASTRONAUTICS

Light-hydrogen capacity ratio configuration method and system considering durability and photovoltaic fluctuation of proton exchange membrane electrolytic cell

The invention relates to a light-hydrogen capacity ratio configuration method and a light-hydrogen capacity ratio configuration system considering the internal durability of a proton exchange membrane electrolytic cell and the photovoltaic rapid fluctuation power, and the method comprises the steps: building a photovoltaic power fluctuation model, an electrolytic cell response model and an equivalent circuit model; a nonlinear differential equation system that the cell voltage is influenced by photovoltaic capacity, electrolytic cell capacity and fluctuation parameters is derived, and electrical constraint conditions based on the durability of the electrolytic cell are set, such as the cell voltage is 1.8-2.5 V, the anode overpotential is less than or equal to 2.2 V, and the voltage change rate is less than or equal to 150mV / s, so that the optimization range of the light-hydrogen capacity ratio k = Cpv / Pelrate is quickly determined. According to the method, the algorithm complexity is effectively reduced, the calculation efficiency is improved, meanwhile, the durability of the membrane and the catalyst in the electrolytic cell is guaranteed, and the economical efficiency and reliability of system equipment are improved.
Owner:TIANJIN UNIV

Frequency index equivalent-based evaluation method for frequency modulation parameters of energy storage equivalent synchronous machine

The application discloses a frequency index equivalent-based energy storage equivalent synchronous machine frequency modulation parameter evaluation method, belongs to the equivalent frequency modulation capacity evaluation field of new energy station, and comprises the following steps: S1, establishing a nonlinear differential equation set of a synchronous generator unit and a new energy power system considering a dead zone link; S2, defining key parameters of the synchronous generator unit and key parameters of the new energy power system; S3, determining that the system average frequency change rate is a frequency response index equivalent target; S4, simulating; S5, constructing a three-dimensional curved surface; S6, searching for energy storage equivalent synchronous generator unit frequency modulation control parameters on the three-dimensional curved surface; and S7, outputting an energy storage frequency modulation capacity quantitative evaluation report. The frequency index equivalent-based energy storage equivalent synchronous machine frequency modulation parameter evaluation method has important guiding significance by using the known frequency modulation characteristics of the synchronous generator to inversely quantify the unknown frequency modulation capacity of the energy storage and considering nonlinear factors in actual operation.
Owner:NORTH CHINA ELECTRIC POWER UNIV

A parameter-unknown chaotic system adaptive synchronization control method based on DNA strand displacement

The application discloses a parameter-unknown chaotic system adaptive synchronization control method based on DNA strand displacement, and comprises the following steps: a chemical reaction module of a nonlinear differential equation with square terms and product terms is obtained by describing emergent reactions, trigger reactions and degradation reaction processes through double-molecule chemical reactions; a Yang chaotic system is constructed by using a DNA strand displacement reaction; an adaptive controller capable of realizing synchronization and an adaptive law expression for unknown parameter estimation are obtained; and the effectiveness of the adaptive controller is verified according to the Lyapunov stability principle. Through the DNA strand displacement mechanism, an internal synchronization mode without the participation of an external chaotic system, i.e. the synchronization between subsystems in a chaotic system, is realized; and under random reactions or other disturbances, the synchronization between the subsystems and the estimation of the unknown parameters by the adaptive law are verified. The method has robustness to parameter deviation, and through triggering a series of DNA reactions, different one-to-one and one-to-many combinations between the subsystems are synchronized.
Owner:DALIAN UNIV

Compressed air energy storage side all-condition dynamic modeling method

The invention relates to the technical field of energy storage system modeling, in particular to a compressed air energy storage side all-working-condition dynamic modeling method which comprises the steps that a third-order nonlinear differential equation set and a compressor characteristic model are built based on the pressure, mass flow and angular speed of a compressor pressurizing chamber of a compressed air energy storage system; a gas-machine-heat dynamic model of the compressor is established; determining control input based on the motor driving torque, constructing a motor driving torque model, constructing an inlet guide vane dynamic model, and constructing a gas storage throttle valve model so as to establish a controller model; and establishing a gas storage inlet pipeline pressure dynamic model and a gas pressure and temperature dynamic equation so as to establish a gas storage joint model. Therefore, the problem that the reliability of the operation state evaluation of the advanced adiabatic compressed air energy storage system is influenced due to insufficient accuracy and robustness of the model caused by insufficient consideration of a coupling mechanism among multi-dimensional state variables in the system in a modeling method in the related technology is solved.
Owner:TSINGHUA UNIVERSITY

Stability analysis method of high-voltage direct current power transmission system and nonlinear modeling method, device and equipment of network converter

PendingCN122292491AConvertersDynamic equation
This application relates to a stability analysis method for high-voltage direct current (HVDC) transmission systems and a nonlinear modeling method, apparatus, and equipment for grid-connected converters. The nonlinear modeling method for grid-connected converters first determines voltage differential equations, voltage differential data, current differential equations, and current differential data by obtaining electrical quantity data. Then, it sequentially determines the main loop dynamic equations and periodic differential equations. By combining the voltage and current differential equations of the control loop dynamics with the main loop dynamic equations and periodic differential equations, a nonlinear differential equation for analyzing the stability of the HVDC transmission system is obtained. This nonlinear differential equation is used to analyze the stability of the HVDC transmission system, solving the problems of existing HVDC transmission systems based on modular multilevel converters where periodic time-varying dynamics and strongly nonlinear limiting behavior induce dynamic bifurcation leading to system instability, and the lack of a universal nonlinear mathematical model and efficient and accurate analysis method.
Owner:ELECTRIC POWER RES INST CHINA SOUTHERN POWER GRID CO LTD

Precision path planning for area coverage

A method for automatically path planning for optimizing a path of a machinery moving in an area, comprises the steps of: taking coordinates of an area contour, a working width of the machinery operating in the area, a mathematical description of the dynamics of the machinery operating in the area in form of a system of nonlinear differential equations, determines segments along the headland path which are not feasible with respect to dynamics of the machinery or whose traversal would result in area coverage gaps. A mathematical algorithm is used with a hierarchical two-step framework in combination with a special coordinate transformation from a time into a spatial domain to formulate geographic high-precision constraints. The hierarchical two-step framework addresses two objectives: a generation of headland paths and a generation of smooth transitions between headland path and mainfield lanes, whereby the first hierarchical step varies for the two objectives.
Owner:FINDKLEIN GMBH

Uncertain nonlinear agent obstacle avoidance control method based on tracking

The invention relates to the technical field of intelligent control, in particular to an uncertain nonlinear intelligent agent obstacle avoidance control method based on tracking. According to the method, an intelligent agent is modeled into an uncertain nonlinear model and converted into an uncertain nonlinear differential equation, a dynamic tracking controller is designed based on input state stability, and an obstacle avoidance controller is designed based on feasible set projection. The invention provides an uncertain nonlinear intelligent agent obstacle avoidance control method based on tracking, and solves or at least alleviates the problems that an existing intelligent agent obstacle avoidance control method is adaptive to an uncertain nonlinear dynamic model and a complex environment, is easy to fall into local optimum, is poor in real-time performance and the like, so that the requirement of obstacle avoidance control on a system is reduced, and the system reliability is improved. And moreover, the obstacle avoidance controller is designed based on the first-order integrator, so that the design process of the obstacle avoidance controller is simplified, and a simple low-order system can control a complex high-order intelligent agent.
Owner:HENAN UNIVERSITY OF TECHNOLOGY

A dc power transmission subsequent commutation failure prediction method and optimization method based on a turn-off angle dynamic equation

The application discloses a DC power transmission subsequent commutation failure prediction method and optimization method based on a turn-off angle dynamic equation, and the prediction method comprises the following steps: obtaining the turn-off angle of the LCC-HVDC inverter side based on the turn-off angle output characteristics of the LCC-HVDC inverter side; analyzing the process of the first commutation failure and the subsequent commutation failure of the LCC-HVDC system based on the inverter side DC current control, the low-voltage current limiting control, the fixed turn-off angle control and the current deviation control; obtaining the transient nonlinear differential equation about the turn-off angle by analyzing the dynamic characteristics of the DC current and the trigger advance angle during the first commutation failure recovery in combination with the control characteristics of the low-voltage current limiting control and the fixed turn-off angle control; and drawing the phase diagram curve of the turn-off angle under different AC voltages and AC voltage change rates based on the transient nonlinear differential equation about the turn-off angle, and obtaining the criterion for predicting the occurrence of the subsequent commutation failure by analyzing the phase diagram curve. The application improves the stability and operation reliability of the system.
Owner:STATE GRID CHONGQING ELECTRIC POWER CO ELECTRIC POWER RES INST +2

Network construction type energy storage fault ride-through capability quantitative evaluation method, device, equipment and medium

The invention discloses a network construction type energy storage fault ride-through capability quantitative evaluation method and device, equipment and a medium, and relates to the field of power electronic stability, and the method comprises the steps: determining a steady-state output power angle of network construction type energy storage before fault ride-through, and determining a second-order nonlinear differential equation of an active power-power angle according to an active power control ring structure; determining an active-power angle output function based on the steady-state output power angle, and performing damping correction on the natural vibration frequency; determining a time domain analytical expression of a transient output power angle of the network-building energy storage during the fault ride-through period by using the corrected vibration frequency, a second-order nonlinear differential equation and an active-power angle output function; and determining an unstable equilibrium point of the network construction type energy storage according to the fault type of the power grid, determining a transient stability discrimination function based on the unstable equilibrium point and the time domain analytical expression, and quantitatively evaluating the fault ride-through capability of the network construction type energy storage through the value of the transient stability discrimination function. And effective quantitative evaluation can be carried out on the fault ride-through capability of the network construction type energy storage.
Owner:STATE GRID CHONGQING ELECTRIC POWER CO ELECTRIC POWER RES INST +1

Blood glucose monitoring control system and blood glucose monitoring control method

The invention relates to a blood glucose monitoring control system and a blood glucose monitoring control method, and belongs to the technical field of blood glucose monitoring instruments. The system comprises a multispectral sensing module (comprising a 480nm / 660nm dual-wavelength camera and an mmu SORS sensor), a wearable multi-modal monitoring unit (integrating a blood glucose sensor and seven physiological parameter acquisition assemblies), a blood glucose metabolism dynamics modeling module (based on a nonlinear differential equation), a dynamic blood glucose prediction engine (TCN-Transform and ST-GCN fusion architecture), an edge calculation unit (FPGA accelerated RANSAC improved algorithm), a data processing unit (data processing unit), a data processing unit (data processing unit), a data processing unit (data processing unit), a data processing unit (data processing unit), a data processing unit (data processing unit) and a data processing unit (data processing unit), a data processing unit (data processing unit) and a data processing unit (data processing unit). A closed-loop feedback actuator (Bluetooth 5.2 insulin pump regulation and control module) and a data security module (homomorphic encryption under a federated learning framework). According to the system, through multi-source data fusion and reinforcement learning optimization, the blood glucose prediction error is remarkably reduced, the emergency response time is shortened, and the accuracy and real-time performance of diabetes management are remarkably improved.
Owner:THE UNIVERSITY-TOWN HOSPITAL AFFILIATED TO CHONGQING MEDICAL UNIVERSITY

Unified detection method and system for electric energy quality of complex power grid

The invention relates to the technical field of power system automation, in particular to a complex power grid electric energy quality unified detection method and system.The method comprises the steps that an electric energy quality disturbance unified representation model is built, and the output quantity is a disturbance characteristic core index set; establishing a nonlinear adaptive filtering dynamic adjustment architecture, and constructing a nonlinear differential equation of the dynamic adjustment architecture based on the unified representation model; filtering the power grid real-time signal based on the dynamic adjustment architecture and outputting an original disturbance feature set; regulating and controlling the value of a dynamic response parameter group in the dynamic regulation framework according to a nonlinear differential equation; a multi-objective optimization algorithm is adopted to execute parameter synchronous optimization processing; and inputting the original disturbance feature set into the unified representation model to generate a disturbance feature core index set. According to the method, the technical contradiction that the dynamic response capability is insufficient due to offline parameter setting in a complex multi-disturbance power grid scene, and cooperative optimization of electric energy quality high-precision measurement and relay protection rapid decision cannot be met at the same time is effectively solved.
Owner:STATE GRID JIANGSU ELECTRIC POWER CO LTD RESEARCH INSTITUTE +3