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117 results about "Algebraic equation" patented technology

In mathematics, an algebraic equation or polynomial equation is an equation of the form P=0 where P is a polynomial with coefficients in some field, often the field of the rational numbers. For most authors, an algebraic equation is univariate, which means that it involves only one variable. On the other hand, a polynomial equation may involve several variables, in which case it is called multivariate and the term polynomial equation is usually preferred to algebraic equation.

Mounting type power transmission line inspection robot adaptive control method, system and device based on deep reinforcement learning and storage medium

The invention relates to the technical field of robot control, in particular to a mounting type power transmission line inspection robot self-adaptive control method, system and device based on deep reinforcement learning and a storage medium. Establishing a multi-modal fusion state vector by synchronously collecting visual sensing, inertial measurement and actuator feedback data, and inputting the multi-modal fusion state vector into a deep reinforcement learning strategy network to dynamically generate a state weight and a control weight adjustment amount of a linear quadratic controller; performing positive qualitative verification, amplitude limitation adjustment and constraint projection processing on the candidate weight matrix; a feedback gain matrix is obtained by solving an algebraic Riccati equation, and control output is calculated according to the state deviation to drive the double mechanical arms to execute inspection actions; designing a multi-target reward function of the comprehensive task completion quality and the energy consumption efficiency, and iteratively updating strategy network parameters by adopting a near-end strategy optimization algorithm; the problem that a fixed weight controller is difficult to adapt to dynamic working conditions of a power transmission line is solved, and a technical scheme is provided for intelligent control of a power inspection robot.
Owner:YUNNAN POWER GRID CO LTD KUNMING POWER SUPPLY BUREAU

SVG-based negative damping elimination method, apparatus and device, and storage medium

The embodiment of the invention discloses a negative damping elimination method, device and equipment based on SVG and a storage medium, and the method comprises the steps: carrying out the impedance scanning of the SVG in a range of 1-3000Hz, obtaining the positive-sequence impedance and negative-sequence impedance of the SVG under different operation conditions, and determining the leading operation condition of the SVG impedance; determining the positive sequence equivalent impedance and the negative sequence equivalent impedance of the SVG grid-connected point according to the positive sequence dominant impedance and the negative sequence dominant impedance of the SVG under the dominant operation condition; determining the value ranges of the positive sequence damping correction value and the negative sequence damping correction value of the SVG; the maximum value of the intersection of the two value ranges is determined as SVG compensation damping, and the SVG compensation damping is merged into an SVG grid-connected point port; according to the scheme, only two unknown parameters including the positive sequence damping correction value and the negative sequence damping correction value are involved, the parameters can be calculated based on an analytic formula pure algebraic equation, the calculation mode is simple, the port impedance characteristic negative damping of the SVG in the full frequency band within the range of 1-3000 Hz can be eliminated, and the problem of high-frequency oscillation is thoroughly solved.
Owner:YUNNAN POWER GRID CO LTD ELECTRIC POWER RES INST

Multi-converter parameter collaborative optimization method for improving small interference stability of active power distribution network

The invention discloses a multi-converter parameter collaborative optimization method for improving the small interference stability of an active power distribution network, and belongs to the technical field of power systems, and the method comprises the steps: building a differential algebraic equation model, and carrying out the linearization of a steady-state operation point, and obtaining a state space model; and a control parameter optimization problem taking the minimization of the spectrum intercept construction as a target is defined, and control parameters are a GFL converter phase-locked loop parameter and a GFM converter virtual damping parameter. First-order sensitivity and second-order sensitivity of eigenvalues to control parameters are calculated based on a matrix perturbation theory and are converted into local quadratic constraint sub-problems. And performing convexity solution by adopting a positive semidefinite relaxation method, adjusting the step length in combination with a line search mechanism, iteratively updating control parameters, and outputting an optimization result after a convergence condition is met. According to the method, the spectral intercept is reduced through multi-converter parameter collaborative optimization, and the weak stability characteristic is improved; the convergence and solvability are improved by utilizing matrix perturbation and positive semidefinite relaxation; and the stability is enhanced and optimized by adopting line search step length adjustment.
Owner:GUIZHOU POWER GRID CO LTD

Educational aid for teaching mathematics

ActiveUS12573316B2Educational modelsTeaching apparatusMathematical ComputingEducational aid
A balance, having an indicator with clearly marked inequalities, provides feedback to a user where the user determines whether they have created an equality or inequality and whether an adjustment is necessary. Users connect mathematical statements with a correct equality or inequality symbol. The indicator provides users with a physical representation of basic math operations, including addition, subtraction, multiplication, and division, as well as fractions, negative numbers, and algebraic equations. Physical adjustments to the balance system correspond to conventional mathematic / algebraic written representation. Constant cubes include several different sets of unit weight. Other cubes or objects are labeled with colored symbols and are provided in a variety of weights and quantities. Opposite chips are labeled with negative signs; line chips are labeled with “x” and “y.” Combinations of the constant cubes, cubes or objects labeled with colored symbols, opposite chips, and line chips are arranged on removable pans on the balance to teach mathematical functions.
Owner:EQUATE-ING IP HOLDCO LLC

Trajectory tracking control method based on data-driven H-infinity fuzzy value iteration

ActiveCN121523061AAdaptive controlFir systemAlgebraic equation
The invention relates to the technical field of automobile steer-by-wire system control, in particular to a trajectory tracking control method based on data-driven fuzzy value iteration. For nonlinearity and uncertainty of a steer-by-wire (SBW) system, a T-S fuzzy technology is adopted to construct a local linear model of the SBW system. Constructing a fuzzy augmented tracking system by introducing a reference signal; secondly, a fuzzy discount coupling algebraic Riccati equation based on a Hamilton-Jacobi-Bellman equation is deduced; and a data-driven fuzzy tracking value iteration (VI) algorithm is designed, and the tracking control problem of the system is solved through online iteration. The algorithm has the prominent characteristics that the dependence on system dynamics information is completely eliminated, and closed-loop trajectory tracking control can be realized without an initial stable control strategy. The method can be widely applied to the fields of intelligent driving, automatic driving steering control and the like, and is particularly suitable for scenes with uncertain system models and difficult control initialization.
Owner:ANHUI UNIV

Deep and far sea wind power time-varying impedance model grid-connected analysis method based on time domain residual error method

The invention discloses a deep and far sea wind power time-varying impedance model grid connection analysis method based on a time domain residual error method, relates to the technical field of power system modeling simulation, and can efficiently and accurately analyze deep and far sea wind power grid connection. The method comprises the following steps: establishing a differential algebraic equation set containing high-capacity submarine cable impedance and a plurality of nonlinear links, and constructing a recursive coefficient matrix; dividing a preset global time domain into a plurality of time domain subintervals, and solving the recursion coefficient matrix in each time domain subinterval by referring to a universal analytic solution represented by a power series explicit operator to generate a global time domain explicit solution corresponding to the preset global time domain; performing discrete Fourier transform on the global time domain explicit solution to obtain a time-frequency domain spectrum result; and constructing a time-varying impedance model according to the differential algebraic equation, setting the time-varying impedance model by adopting a time-frequency domain spectrum result, and analyzing the deep and far sea wind power grid-connected control system by utilizing the set time-varying impedance model.
Owner:EAST CHINA BRANCH OF STATE GRID CORP

Frequency lowest point evaluation method considering low-voltage ride-through process of new energy unit

The invention discloses a frequency lowest point evaluation method considering a low-voltage ride-through process of a new energy unit, and belongs to the technical field of power systems. The method comprises the following steps: establishing a whole-system quasi-steady-state model, respectively constructing models for a synchronous machine, a new energy unit and a load, and replacing a differential equation of power electronic equipment such as the new energy unit with a nonlinear algebraic equation; based on the model, node voltage and injection current are updated through an alternate iteration method, key quasi-steady-state points when the new energy unit enters a low-voltage ride-through state and is in an off-network state are identified, and overall unbalanced power of the system is output; inputting the unbalanced power of each key quasi-steady-state point into the ASF model, and fitting a system frequency curve to obtain the lowest point of the frequency by considering the power vacancy of the low-voltage ride-through and off-network stages. The method does not need to depend on time domain simulation, can quickly and accurately evaluate the lowest point of the frequency, and is suitable for online stability evaluation of the power system.
Owner:XI AN JIAOTONG UNIV

Thermal power generating unit APS automatic start-stop full-process control method and system

PendingCN121055824AMachines/enginesEngine componentsDifferential algebraic equationAlgebraic equation
The invention relates to the field of electric power, discloses a thermal power generating unit APS automatic start-stop full-process control method and system, and is used for solving the contradiction among safety, economy and rapidity of a traditional APS system. The method comprises the steps of establishing a differential algebraic equation system based on unit physical parameters to generate a unified model constraint set; generating a reference trajectory representing energy conversion efficiency and power in a differential flat space according to the start-stop target curve; predicting a thermal stress change rate through a fractional order differential operator based on the metal temperature to generate a safety margin instruction; generating an energy coordination correction instruction according to the Hamiltonian energy network balance point of the boiler heat storage and steam turbine kinetic energy solving port; and mapping the reference trajectory into a control instruction, integrating thermal stress constraint and energy coordination correction, and then distributing and executing. Safe and efficient start-stop control under full-process physical constraints is achieved, start-stop safety and economy are improved, and the service life of equipment is prolonged.
Owner:DATANG INT POWER GENERATION CO LTD

Power system time sequence simulation system considering security constraints

PendingCN121413200AGeometric CADDesign optimisation/simulationDifferential algebraic equationAlgebraic equation
The invention relates to the technical field of power system simulation, and discloses a power system time sequence simulation system considering security constraints. The system comprises a power grid topology analysis unit, a dynamic security domain calculation unit, a time sequence constraint modeling unit, a simulation track generation unit and a check feedback unit. The power grid topology analysis unit obtains element connection relations and electrical parameters, and generates a topology description file containing a node admittance matrix; the dynamic safety domain calculation unit obtains the voltage stability limit and the power angle stability boundary of each working condition, and forms a safety domain boundary set; a time sequence constraint modeling unit combines the set with a predefined time interval to build a security constraint time sequence model containing a transient process; the simulation trajectory generation unit solves a differential algebraic equation set by using an implicit trapezoidal integral method, and outputs a state variable trajectory with a timestamp; and the check feedback unit compares the track with the security domain boundary, marks an abnormal segment and generates a correction instruction. The system realizes fusion of security constraint and time sequence simulation.
Owner:POWER ECONOMIC RESEARCH INSTITUTE OF JILIN ELECTRIC POWER CO LTD

Dynamic grouping method and device for heterogeneous direct current delivery system

The invention provides a dynamic grouping method and device for a heterogeneous direct current delivery system, and relates to the technical field of dynamic analysis and control of a power system, and the method comprises the steps: deducing a linear time-varying variation equation which is satisfied by the trajectory sensitivity of a system state trajectory to a system parameter vector based on a parameterized differential-algebraic equation model; calculating the track sensitivity of each device to a system parameter vector, projecting the track sensitivity to a common connection point corresponding to each device, and constructing a unified sensitivity feature vector of each device; calculating the dynamic similarity between the devices based on the unified sensitivity feature vector, and constructing a mixed similarity matrix in combination with the electrical distance similarity between the devices; and feature decomposition and feature vector clustering are carried out based on the mixed similarity matrix, and dynamic clustering of heterogeneous equipment is realized. According to the dynamic grouping method provided by the invention, unified grouping of heterogeneous equipment such as a synchronous machine and a converter can be realized in a heterogeneous power system containing high-proportion new energy and direct-current power transmission.
Owner:TSINGHUA UNIVERSITY +1

A method and system for optimizing a press-pack IGBT device package structure

The application relates to the technical field of power electronics, and discloses a press-contact type IGBT device packaging structure optimization method and system. The method comprises the following steps: constructing an equivalent model of a press-contact type IGBT device; constructing a differential algebraic equation for uniformly describing the equivalent model of the press-contact type IGBT device and circuit port variables; converting the differential algebraic equation into a nonlinear algebraic equation group through time domain discretization, and constructing an iteration matrix with a global state vector as a derivation object according to a solving mode of the nonlinear algebraic equation group; performing low-dimensional subspace projection on the iteration matrix based on a Krylov subspace, and combining residual minimization to solve a linear subproblem of the iteration matrix, so that current uniformity characteristic results of the press-contact type IGBT device are obtained; and the packaging structure of the press-contact type IGBT device is optimized based on current density distribution reflected by the current uniformity characteristic results. The application can improve the current uniformity and operation reliability of the system.
Owner:MAINTENANCE BRANCH COMPANY STATE GRID ZHEJIANG ELECTRIC POWER

Multi-stage separation unit initialization method and system based on virtual transient model and application

ActiveCN121257111ADesign optimisation/simulationComplex mathematical operationsDifferential algebraic equationAlgorithm
The invention discloses a multi-stage separation unit initialization method and system based on a virtual transient model and application, and relates to the technical field of chemical process simulation, and the method comprises the steps: constructing a virtual transient differential equation of a multi-stage separation unit; constructing a virtual differential variable associated equation of the multi-stage separation unit; constructing a virtual transient model of the whole tower of the multistage separation unit; solving the virtual transient model; and outputting the initial estimation value. According to the multi-stage separation unit initialization method and system based on the virtual transient model and the application, when a dynamic process differential algebraic equation model is constructed, the use of a complex hydraulics association formula and structural information of the separation unit is avoided, the time-varying item is virtual, the method does not need to be based on a real physical process, and the time-varying item is saved. However, the integral is completely equivalent to the algebraic equation model when reaching the steady state, so that the initialization process of the multi-stage separation unit based on the virtual transient model is easier to solve, and the method has the advantages of high calculation efficiency and higher robustness.
Owner:TIANJIN UNIV

Distributed photovoltaic aggregation frequency modulation standby optimal configuration method considering node frequency security constraint under transmission and distribution cooperation

The invention discloses a distributed photovoltaic aggregation frequency modulation standby optimal configuration method considering node frequency security constraints under transmission and distribution cooperation. The method comprises the following steps: describing uncertainty of photovoltaic aggregation frequency modulation capability by using a Gaussian mixture model, and establishing a power transmission network node frequency response model containing frequency space distribution characteristics; taking minimization of system power generation and frequency modulation reserve cost as a target, and combining opportunity constraint planning to construct an optimal configuration model; a response model is reduced based on a frequency divider theory, a Bernstein polynomial approximates frequency dynamics, and a differential algebraic equation is converted into an algebraic equation; then, binary expansion and Gaussian mixture model linear invariance are utilized to convert the model into a mixed integer linear programming model, and Bernstein polynomial convex hull property tightening constraint is combined; and finally, solving the model to obtain the optimal photovoltaic aggregation frequency modulation reserve capacity and control parameters. The frequency space distribution is accurately described, the problem of insufficient frequency safety risk identification is solved, and the frequency safety level of a power system is improved.
Owner:ZHEJIANG UNIV +1

Method for analyzing time-frequency characteristics of collision vibration by using segmented B-spline wavelet collocation method

PendingCN121434540AComplex mathematical operationsBasis (linear algebra)Direct computation
The invention discloses a method for analyzing time-frequency characteristics of collision vibration by using a segmented B-spline wavelet collocation method, which comprises the following steps of: (1) establishing a dynamic equation for wavelet discretization, discretizing a dynamic control equation of a collision-vibrator system by using a 4-order B-spline wavelet basis function, and establishing a nonlinear algebraic equation set about a wavelet coefficient; (2) carrying out segmented iterative solution on the time domain, dividing the whole time domain into a plurality of sub-time periods which are connected in sequence, and carrying out iterative solution on the nonlinear algebraic equation set in each sub-time period to obtain a global wavelet coefficient; and (3) analyzing the time-frequency characteristics, and directly calculating energy distribution based on the wavelet coefficient to realize time-frequency joint characterization. The invention aims to provide a method which can fuse solution of system response and extraction of time-frequency characteristics in a unified mathematical framework, and realizes high-precision time-frequency joint characterization by directly solving wavelet coefficients, thereby overcoming inherent defects of an existing two-step method.
Owner:NANJING UNIV OF SCI & TECH +1

Method and apparatus for predicting temperature change of electronic component based on pentahedron unit

ActiveCN121744760BEliminate risk of damageaccurately reflectAlgebraic equationGoverning equation
This invention provides a method and device for predicting temperature changes in electronic components based on pentahedral elements. The method includes: meshing the electronic component into pentahedral elements based on its structural parameters; determining the three-dimensional transient heat conduction governing equation and initial algebraic equation for the target region; determining correction terms based on the virtual node domain defined for the pentahedral elements, the Galerkin weight function, the three-dimensional transient heat conduction governing equation, and the initial algebraic equation; correcting the initial algebraic equation based on the correction terms to obtain the target algebraic equation; determining the final algebraic equation based on the target algebraic equation and a preset time interval; solving the final algebraic equation to obtain the transient heat conduction temperature simulation result; adjusting design parameters based on the transient heat conduction temperature simulation result; and implementing optimized design of the electronic component based on the adjusted design parameters.
Owner:UNIV OF ELECTRONIC SCI & TECH OF CHINA CHENGDU COLLEGE

Multi-region frequency security unit commitment method and device based on bernstein polynomial

The application discloses a multi-region frequency safety unit scheduling method and device based on Bernstein polynomials, and the method is based on the optimal distribution of the dynamic primary frequency modulation response of a synchronous generator, a speed governor dead zone and a frequency modulation backup, and a multi-region frequency response model is constructed; the integral-differential algebraic equation of the multi-region frequency response model is approximated through Bernstein polynomials to obtain an algebraic expression of the multi-region frequency dynamics, and a multi-region frequency safety constraint is constructed according to the algebraic expression; the multi-region frequency safety constraint is embedded into a unit combination problem to construct a multi-region frequency safety constraint unit combination model; through a self-adaptive double-layer decomposition algorithm, a mixed integer programming problem of the multi-region frequency safety constraint unit combination model is decomposed into a main problem and a sub-problem; and through solving, a multi-region frequency safety unit scheduling scheme is obtained. The application accurately captures the frequency dynamic difference between regions and improves the frequency safety of a high-proportion new energy power system.
Owner:TIANJIN UNIV

Method for transient stability boundary description of multi-inverter hybrid system based on reverse integration

ActiveCN120978714BBroaden the operating domainreduce conservatismSingle network parallel feeding arrangementsComplex mathematical operationsDifferential algebraic equationTransient state
The application provides a multi-inverter hybrid system transient stability boundary delineation method based on reverse integration, and belongs to the field of electrical engineering. The delineation method combines a circuit model of a grid-constructed inverter, a grid-following inverter and an infinite grid hybrid system and a virtual synchronous machine mathematical model of the grid-constructed inverter, derives a second-order differential-algebraic equation set of the hybrid system, further obtains system steady-state equilibrium points by solving the equation set and classifies, and reversely integrates from the type I unstable equilibrium point to obtain a transient stability boundary of the hybrid system. The application is simple and intuitive, has a solid theoretical basis, can quickly and accurately identify the transient stability boundary of the grid-connected inverter system, and has important significance for analyzing the transient stability of the multi-grid-connected inverter hybrid system.
Owner:HEFEI UNIV OF TECH +1

Power system step backspacing simulation method and system considering switching event

ActiveCN121461295AAc network circuit arrangementsDifferential algebraic equationTransient state
The invention provides an electric power system step backspacing simulation method and system considering switching events, and belongs to the technical field of electric power system electromechanical transient simulation, and the method comprises the steps: executing transient simulation step by step, carrying out the alternate iteration of a differential algebraic equation set, scanning the switching events of a DC system in the iteration process, scanning other switching events after the iteration convergence, and carrying out the step backspacing simulation. Whether step backspacing needs to be carried out or not is checked according to a backspacing criterion of the step backspacing strategy; if so, carrying out a rollback operation and adjusting the simulation step length according to a rollback simulation strategy; switching the scanned switching event, and keeping the state variable of the system unchanged after the switching is completed; according to the scheme, whether the next step of simulation continues to be executed or not is checked, if simulation continues to be executed, the step length of the next step needs to be adjusted according to the criterion of step length increase and step length decrease, and the scheme has good technical compatibility and also has excellent expansibility.
Owner:SHANDONG UNIV

Power grid power flow analysis method and device based on quotient gradient method and neural network

The invention discloses a power grid power flow analysis method and device based on a quotient gradient method and a neural network, and the method comprises the steps: converting a nonlinear algebraic equation set of flow calculation into an ordinary differential equation based on the quotient gradient method, and constructing a physical information neural network model according to the ordinary differential equation. A system state reference trajectory is generated through an ordinary differential equation solver to serve as a training data set, a composite loss function containing a predicted value and reference trajectory error and a predicted value time derivative and theoretical derivative error is defined, and a training model is iteratively trained. And inputting to-be-calculated working condition parameters and steady-state set time into the trained model, and outputting a steady-state power flow solution through forward propagation. According to the method, the convergence, the physical interpretability and the generalization ability under the ill-conditioned or extreme working condition are improved, and the real-time online analysis requirement is met.
Owner:TIANJIN UNIV +2

Method for predicting air trapping area in LCM filling process based on compressible two-phase flow model

The invention belongs to the technical field of simulation defect prediction, and particularly discloses an LCM filling process air trapping area prediction method based on a compressible two-phase flow model, which comprises the following steps: establishing the compressible two-phase flow model for predicting the air trapping area evolution in the LCM filling process, and determining a control equation set in the LCM filling process based on the compressible two-phase flow model; performing numerical discretization of a time domain and a space domain on the compressible two-phase flow model by adopting a finite volume method to obtain a discretized algebraic equation set corresponding to the control equation set; and solving the discretization algebraic equation set based on a pressure implicit operator splitting algorithm to obtain pressure values, speed values and unit phase fraction values of the resin fluid and the air fluid in the LCM filling process, and determining a three-dimensional numerical simulation result of air trapping area evolution based on the pressure values, the speed values and the unit phase fraction values. According to the invention, the prediction accuracy and effectiveness of the air trapping area in the LCM filling process can be improved.
Owner:HUAZHONG UNIV OF SCI & TECH

Trajectory planning method and device for water-air cross-medium cruise device

The invention relates to a trajectory planning method and device for a water-air cross-medium cruise device. The method comprises the following steps: acquiring a cruise task demand and decomposing the cruise task demand into a series of five-dimensional waypoints including a position, a course angle and a pitch angle; dividing the trajectory connecting the five-dimensional waypoints into a plurality of sections, respectively adopting a polynomial function to represent the five-dimensional state of each section of trajectory, performing coefficient solution on the polynomial function of each section of trajectory to obtain a corresponding polynomial coefficient, and obtaining each section of complete five-dimensional space-time trajectory; an algebraic equation is established on the basis of the physical constraint that the thrust of the water-air cross-medium cruise device along the y axis of a machine body is constantly zero, so that the roll angle at each moment is reversely analyzed from the five-dimensional space-time trajectory, a complete six-degree-of-freedom posture is obtained, a control instruction of the water-air cross-medium cruise device is generated, and operation control is carried out. Compared with the prior art, the method has the advantages that the problems of high precision and smooth trajectory planning of the water-air cross-medium cruise are solved, and the task execution capability and the flight stability of the water-air cross-medium cruise are remarkably improved.
Owner:SHANGHAI TONGJI INDEPENDENT INTELLIGENT UNMANNED SYSTEMS RESEARCH INSTITUTE +1

Method, device and equipment for constructing power system model based on large language model

The application provides a method, device and equipment for constructing a power system model based on a large language model, relates to the technical field of model construction, and solves the defect that the comprehensive performance of a model obtained by dynamic modeling of a power system is poor. The method comprises the following steps: based on the operation data of the power system under a disturbance working condition, a plurality of differential equation candidate models are constructed and iteratively trained to determine the comprehensive evaluation parameters of each differential equation candidate model; in the case that at least one differential equation candidate model meets a convergence condition, a target differential equation candidate model with optimal comprehensive evaluation parameters is determined; based on target algebraic variables and target input variables corresponding to the target differential equation candidate model, a plurality of algebraic equation candidate models are constructed and iteratively trained to determine a target algebraic equation candidate model with optimal comprehensive evaluation parameters; and based on the target differential equation candidate model and the target algebraic equation candidate model, a power system model is constructed.
Owner:PEKING UNIV

A distributed power distribution system unified scale load modeling simulation method and system

The application relates to the field of power distribution system simulation, in particular to a distributed power distribution system unified scale load modeling simulation method and system, which comprises the following steps: denoising and fitting a wideband signal to obtain a multiscale signal; obtaining a Hankel matrix time-varying extended model based on the multiscale signal and historical modal parameters and solving to obtain real-time modal parameters; constructing a coupling matrix based on the real-time modal parameters, fitting a fast action layer state equation and a slow action layer state equation by using the coupling matrix to obtain a unified coupling equation; transforming and decoupling the unified coupling equation to obtain a mixed differential-algebraic equation group; and solving the mixed differential-algebraic equation group by using a preset step length switching rule based on a dominant dynamic type to obtain full-time domain simulation results of the distributed power distribution system. The application can effectively solve the problems of time scale fragmentation and insufficient parameter identification accuracy in traditional load modeling.
Owner:CHINA ELECTRIC POWER RESEARCH INSTITUTE CO LTD +2

Compiler for supporting general symbolic-numeric nonlinear solving in implicit differential equation solvers via canonical forms in compressed representation

A system for solving nonlinear problems in implicit differential equations comprises hardware processors that transform differential equation systems into a unified canonical form enabling efficient numerical solving across multiple integration methods. The processors represent differential equations in a reduced canonical form G(x; v1, v2, γ, c)=v1+Mx−γ(h) f(x+v2, tn+ch) incorporating solution vectors, integrator parameters, mass matrices, and time parameters. The system generates model-specific mapping functions N(x)=y and N−1(y, γ, v1, v2)=x that transform between differential algebraic equation states and compressed nonlinear solver states, eliminating algebraically redundant variables through symbolic analysis. This compressed representation reduces computational complexity from O(n3) to O(m3) where m<n, while integrator-specific functions v1, v2, and γ(ρh) encode method-specific discretization parameters.
Owner:JULIAHUB INC

Unmanned aerial vehicle cluster confrontation control method and system based on fractional order dynamics equation

This invention provides a method and system for UAV swarm adversarial control based on fractional-order dynamic equations. The method includes: performing long-range correlation detection on historical trajectory data of the UAV swarm; reconstructing the state space of the UAV swarm based on long-range correlation characteristics and state data; constructing fractional-order game dynamic equations based on the state space; performing discrete dimensionality reduction on the equations to obtain a set of algebraic equations; solving the set of algebraic equations; generating flight control commands based on the policy density evolution results corresponding to the solved Nash equilibrium and issuing them to the UAV swarm to control the UAV swarm in game adversarial combat. This method overcomes the shortcomings of existing integer-order game models in describing memory effects, nonlocality, and anomalous diffusion, and achieves high-precision prediction and efficient solution of multidimensional nonlinear adversarial combat in complex dynamic environments. It significantly reduces computational complexity and fundamentally solves the problems of long-term prediction distortion and high-dimensional convergence difficulties in traditional models.
Owner:INST OF AUTOMATION CHINESE ACAD OF SCI

Display method of mathematical paraboloid structure

PendingCN122067453ABridging the cognitive gapBoth scientific and scientificEducational modelsAlgorithmAlgebraic equation
The invention belongs to the technical field of education and teaching, and relates to a mathematical paraboloid structure display method comprising the following steps: receiving paraboloid parameters set by a user and coordinate system origin offset; according to the received parameters and based on the received parameters, horizontal section planes are generated in the z-axis direction through layer-by-layer sectioning according to the step length, and an implicit solution set of an algebraic equation on each section plane is solved to obtain a quadratic curve contour; after stacking processing is conducted along the z axis, a continuous smooth curved surface is generated, and a space grid model for generating a paraboloid is obtained; and rendering the space grid model of the paraboloid to obtain a space geometric model, and by constructing a complete technical system which takes algebraic parameters as drive, geometric generation as a core, multi-modal interaction as support and mathematical preciseness as guarantee, realizing normal form transformation from static result display to a dynamic construction process. The generation logic and geometric characteristics of the paraboloid can be visually, accurately and interactively revealed, and the teaching cognition effect is effectively improved.
Owner:CHANGCHUN NORMAL UNIV

Fault analysis method based on electromagnetic over-limit signal, electronic equipment and medium

The invention provides a fault analysis method based on an electromagnetic over-limit signal, electronic equipment and a medium. The method comprises the following steps: constructing a correlation model between the electromagnetic over-limit signal and an operation code bit flipping event; acquiring a plaintext P and a correct ciphertext C thereof in a correct encryption process; in response to the monitored and identified electromagnetic over-limit signal, positioning a fault point where an operation code bit flipping event occurs according to the correlation model; acquiring a plaintext P and a fault ciphertext C'corresponding to the plaintext P; constructing an algebraic equation according to the correct ciphertext C and the fault ciphertext C '; solving the algebraic equation to obtain an independent variable; calculating a last-round key according to the independent variable and the correct ciphertext C; and processing the last-round key according to a key expansion algorithm to obtain a master key.
Owner:ZHEJIANG UNIV

A single-stage multi-port inverter control method based on general algebraic modulation

This invention discloses a control method for a single-stage multi-port inverter based on general algebraic modulation. By innovatively transforming the complex physical mapping relationship between the duty cycle of each switch and the modulation target into an intuitive problem of solving a set of algebraic equations, the method can generate drive pulses by solving the derivative sub-equations based on the real-time changing system state to obtain the duty cycle difference between adjacent switches and then calculating the duty cycle of all switches. This algebraic-level control logic removes the constraints of the modulation method on the actual hardware topology. When the number of DC ports is changed, there is no need to redesign or modify the underlying modulation rules, thus exhibiting high versatility and scalability.
Owner:UNIV OF ELECTRONICS SCI & TECH OF CHINA +1

A method for modeling electromechanical coupling dynamics of an electric vertical take-off and landing aircraft based on differential-algebraic equations

A kind of electromechanical coupling dynamics modeling method of electric vertical take-off and landing aircraft based on differential algebraic equation belongs to electric vertical take-off and landing aircraft technical field.First, the motor dynamics equation in eVTOL electric propulsion system is established according to motor parameters;Second, according to the geometric configuration and inertia parameters of eVTOL, the dynamics equation of fuselage multibody system is established, and the aerodynamic model is applied;Third, the motion driving equation is used to couple based on the general mechanical load calculation scheme of Lagrange multiplier;Finally, the electromechanical coupling dynamics model of eVTOL is established, which is discretized by trapezoidal-Newmark hybrid discrete format, and efficient solution is realized based on Newton iteration method, and it is verified by eVTOL vertical take-off.The invention avoids the defects of traditional simplified model ignoring motor transient characteristics and non-coupling modeling without real-time load feedback, improves the motion response and energy consumption calculation accuracy, and provides reliable dynamics modeling basis for eVTOL energy consumption optimization and commercial design.
Owner:DALIAN UNIV OF TECH +1