153 results about "Algebraic equation" patented technology

The invention relates to the technical field of water supply pipe networks, and discloses a multi-pump-room collaborative intelligent water supply frequency conversion regulation and control method, which comprises the following steps: initializing sensor calibration and data acquisition, generating a standardized data packet by using Kalman filtering, constructing a differential algebraic equation model, and online updating a pipe network topological characteristic matrix in combination with a mixed basis function observer. Layered optimization control and frequency conversion cooperative regulation and control are driven, 30-100ms-level real-time solution of a differential equation is realized by means of a hardware acceleration module, a three-dimensional pressure cloud picture is finally generated, and early warning is triggered based on a current harmonic threshold value. The transient fault capturing capability is enhanced by dynamically adjusting the data acquisition frequency, and the problem of signal distortion caused by traditional fixed sampling is solved; resource allocation is optimized and calculated in combination with a pipe network topology model dimension reduction technology, and calculation power waste in large-scale monitoring is reduced; and dynamic reconstruction of the model is driven by abnormal data to realize system self-adaption, so that manual parameter adjustment deviation is avoided, and the prediction precision and the diagnosis reliability are remarkably improved.

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.

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.

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.

According to the cluster system simulation solving method and device, the storage medium and the computer equipment provided by the invention, during simulation solving, the cluster system is divided into the multiple independent subsystems according to the topological structure of the cluster system, and the digital model of each subsystem is constructed, so that the model matrix dimension is reduced, and the single-step calculation amount is reduced; and then differential solution is carried out on the digital model of each subsystem to obtain a differential solution result, and then algebraic solution is carried out, so that mutual containment of the two subsystems is avoided, and the speed is increased. Before algebraic solution, dependence parameters of the cluster system are determined according to the controlled relationship among the subsystems, and whether the cluster system has an algebraic ring is determined and judged based on the dependence parameters; if yes, carrying out iterative solution on each digital model by adopting a Newton-Raphson iterative algorithm to avoid error accumulation caused by closed-loop dependence; and if not, sequentially solving the algebraic equations in the digital models by adopting a display function, and improving the solving efficiency to a millisecond level.

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.

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.

The invention provides a three-dimensional geological modeling method, system and equipment based on a particle dynamics system. The method comprises the following steps: carrying out data preprocessing on a drilling data set of a to-be-built geological model region to obtain a stratum attribute known point set; discretizing the to-be-built geologic model area, and performing stratum parameter initialization processing on each spatial discrete coordinate point in the to-be-built geologic model area according to the stratum attribute known point set to obtain initial stratum parameters of a to-be-built geologic model; based on the initial stratum parameters and the drilling data set, a weight function expressed by spatial distribution information is established; establishing a link relation information matrix according to grid division and section discontinuity information of the to-be-established geological model area; based on a particle dynamics theory, establishing a system dynamics equation in a differential algebraic equation form by applying the initial stratum parameters, the weighting function and the link relation information matrix; and solving the system kinetic equation to establish a three-dimensional geological model of the to-be-established geological model area.

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.

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.

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.

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.

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.

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.

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.

A method for calibrating the feedback gain of an LQI controller implemented in an electronic control unit (25) operatively connected for controlling the operation of a physical electrical or electromechanical device (26) of a dynamic physical system (28), in particular a vehicle powertrain (4), wherein the method of calibrating the LQI controller comprises: obtaining values of various physical parameters of the dynamic physical system (28); substituting the obtained value of the physical parameter into a predetermined equation for calculating the value of each term of a P matrix, where the P matrix is a solution to the algebraic Riccati equation, and where the predetermined equation comprises the physical parameter of the system (28); and calculating a new feedback gain of the LQI controller based on the arbitrary selected positive value of r based on the matrix equation, wherein terms of the matrix K correspond to the feedback gain.

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.

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.

The invention discloses a wing angle adjusting system and a flight demonstration method, and relates to the technical field of wing simulation adjustment, the adjusting system comprises a wind field simulation module and an attack angle adjusting module; the wind field simulation module takes a discrete simulation space as a unit, establishes a mass conservation equation and a momentum conservation equation based on a Navier-Stokes equation, and discretizes the momentum conservation equation into an algebraic equation set by adopting a second-order windward format and a central difference format; a simulated wind field is generated through a semi-implicit method of a pressure coupling equation set according to constraint iteration of an algebraic equation set and a mass conservation equation; the attack angle adjusting module is used for placing the wing 3D model in a simulation space, establishing a model of lift force, resistance and rotation amount about an attack angle, and iteratively acquiring an optimal attack angle by adopting a whale optimization algorithm; according to the demonstration method, demonstration is carried out based on wind field simulation parameters and the optimal attack angle, an actual wind field vector diagram and a wind flow curve are calculated, and accurate simulation of a wind field, attack angle self-adaptive adjustment and matched adjustment demonstration are achieved.

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.

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.

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.

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.

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.

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.

The invention discloses a valve structure simulation method and device based on finite element analysis and a readable storage medium, and belongs to the technical field of valves, the simulation method mainly comprises a multi-physics field coupling method, control equations of a plurality of physics fields are simultaneous to obtain a control equation set, and the control equation set comprises a physics field parameter array corresponding to the physics field; the control equation set comprises a fluid mechanics equation, a damp-heat conduction equation and an elastic mechanics equation, a unified equation set is formed, and then discretization processing is carried out; performing discretization to convert a continuous partial differential equation into an algebraic equation set; for a transient problem, a display or implicit time integration scheme is adopted to perform time discretization on a simultaneous equation. An apparatus includes a memory, a processor, and a computer program. A terminal program for executing the method is stored in the storage medium. Factors such as fluid flow, damp heat conduction and structural mechanics can be considered at the same time, the simulation real-time performance is improved by integrating an advanced method and an optimization strategy, and the precision is improved while the working efficiency is ensured.

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.

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.

An aerosol provision device comprise a controller configured to receive input data relating to a charge level of a power source and a memory configured to store input data. The controller is configured to use an algebraic equation to approximate a variation in the charge level over a period of time and store the algebraic equation in the memory.