24 results about "Eulerian method" patented technology

According to the real-time path planning method for the arm end mechanism of the humanoid robot, all joints of the mechanical arm of the humanoid robot can be controlled to rotate through path planning, and therefore the purpose that the end executing mechanism of the humanoid robot reaches the designated position is accurately achieved. According to the algorithm, a target point which a robot end execution mechanism needs to reach, an iteration stopping distance and a stopping number in iteration are determined according to engineering requirements, the L2 norm of a target position posture and a current position posture error is minimized through a Newton-Euler method, and the optimal position at the next moment and the corresponding iteration joint angle are solved. And through repeated iterative calculation, the tail-section executing mechanism of the mechanical arm can reach the target point accurately finally. The target passes mathematical simulation verification, and finally, when the tail end of the mechanical arm reaches the target point through planning, the position error reaches the order of magnitude of 1e-10m, and the high-precision planning effect is displayed. The algorithm planning precision is high, and the method has a good application prospect.

The application discloses a general reconfigurable simulation system of a power electronic converter, comprising: a dynamic element module, which is used for solving a dynamic element state equation according to a forward Euler method to obtain a dynamic element state variable, and sending the dynamic element state variable to a switch module according to a preset selection instruction; the switch module is used for constructing a general matrix model for a bridge arm switch of the converter, processing the dynamic element state variable through the general matrix model, and generating a switch voltage and a switch state instruction; a neutral point voltage solving module, which is used for constructing a neutral point voltage model for a three-phase rectification or inversion circuit according to the switch voltage and the switch state instruction, and solving to obtain a neutral point voltage; and a power supply module, which is used for providing different power supply voltages for the neutral point voltage solving module, wherein the power supply voltages include three-phase alternating voltages and a direct current voltage. The technical problems that the simulation adjustment flexibility is poor in different scenes, the modeling is complicated due to the increase of system element complexity, and the simulation compilation is time-consuming in the prior art are solved.

This invention provides a simulation method for test equivalent signals based on the Euler discrete model. It primarily solves the problem of equivalent generation of gyroscope angle signals in test equivalent converters, enabling high-precision reproduction of the complex dynamic angle changes of an aircraft during flight. This overcomes the difficulty of accurately simulating gyroscope angle signals during ground testing. First, using predetermined aircraft pitch channel altitude trajectory data, a fast differentiator is used to solve for the differential data of the altitude and horizontal trajectories, thereby solving for the aircraft pitch angle and pitch velocity data. Then, the Euler method is used to establish a discrete measurement model of the gyroscope, solving for the measured value of the pitch velocity. Considering the influence of error drift, integration is performed to obtain the gyroscope's measurement signal of the pitch angle. This outputs a high-precision result of the gyroscope angle changes during high-altitude flight. This method has the advantages of high simulation accuracy and good agreement with reality.

The invention discloses an unmanned tracked vehicle trajectory tracking method based on H infinity model prediction hybrid control, which comprises the following steps: firstly, establishing a tracked vehicle dynamics model, and discretizing through a forward Euler method; an H infinity and MPC double-controller parallel computing architecture is adopted, and an MPC controller combines a reference trajectory and a prediction state to generate an optimal control quantity of an adaptive constraint through rolling optimization to minimize a tracking error and a control cost; multi-source interference is introduced into the H infinite controller, and disturbance compensation control quantity is generated through interference modeling, linear processing and Riccati equation solving; and the optimal control quantity and the disturbance compensation control quantity are fused, a crawler executing mechanism is driven, a new state is fed back, and closed-loop feedback control is achieved. The method not only has the dynamic optimization capability of the MPC controller, but also has the strong anti-interference capability of the H infinite controller, realizes synchronous consideration of optimization and robustness, and ensures that the system always keeps trajectory tracking precision and stability under complex working conditions through closed-loop feedback control.

The application discloses a kind of gas-solid two-phase flow self-adapting simulation prediction method, system, medium and product, belong to the field of digital simulation of fluid dynamics, the method is: obtaining industrial equipment geometry, particle and fluid data, constructs gas-solid two-phase flow CMPPIC model;Wherein, continuous phase is with Euler method, discrete phase is with Lagrange particle bag representation;Perform time advance iteration to termination condition, output result, wherein each round of iteration includes mapping particle bag data to Euler cell, obtaining particle statistical information and marking fixed state particle according to rules;Freeze fixed cell particle volume fraction, calculate porous medium parameter, reconstruct its continuous phase momentum conservation equation;Based on reconstruction and unreconstructed equation, update flow field, while updating the particle motion of unmarked fixed state cell. By implementing the application, the problem that calculation efficiency and physical precision are difficult to consider in simulating fixed particle structure in the prior art can be solved.

The invention discloses a fluid-solid coupling calculation method for predicting the vortex-induced motion response of an underwater single anchor system, and the method comprises the steps: dividing a flow field calculation domain based on a multi-region overlapping grid technology, and achieving the data transmission through boundary point interpolation; establishing an anchor chain discrete dynamical model by adopting a concentrated mass method, and iteratively solving an anchor chain form and tension distribution; a six-degree-of-freedom rigid body dynamic model of the mooring body is established by applying a Newton-Euler method, and constraint conditions such as hydrodynamic force and anchor chain tension are integrated; a flow field is solved through a computational fluid dynamics method, and bidirectional data exchange of fluid load, anchor chain tension and structural motion is realized by using a custom function. The method has the advantages that the problem of large-displacement motion simulation of the mooring system is effectively solved through a multi-region overlapping grid and a cross-platform collaborative architecture, the six-degree-of-freedom vortex-induced motion response of the mooring body can be predicted in a high-precision mode, and whole-process visualization of dynamic changes of a flow field is achieved.

The application discloses a nine-switch converter flexible interconnection system and a switching loss control method and device thereof. αβ The method comprises the following steps: firstly, 27 voltage space vectors are obtained by constructing a nine-switch converter mathematical model; secondly, a system Coordinate system mathematical model is established, a prediction model is obtained through forward Euler method discretization processing, and a weight coefficient value function is designed to accurately track the current; then, voltage vectors are selected and inserted into zero vectors, and a fixed switching frequency switching sequence is designed; finally, the action time of the voltage vector is determined through duty cycle modulation, and the optimal voltage vector is periodically and alternately selected. The application effectively solves the problems of the existing system, such as unfixed switching frequency, uneven loss, large current harmonic and heavy calculation burden, balances the power device loss, prolongs the service life of the device and improves the system stability. The application can realize the bidirectional power flexible interconnection between two three-phase power grids and guarantee the system operation stability and power quality.

The invention provides an urban pavement rainfall runoff particulate matter transmission rate calculation method based on a control layer concept, and the method comprehensively considers the influence of raindrop splashing and runoff shearing composite driving effect on particulate matter transmission by establishing a double-layer conceptual model comprising a static control layer and a dynamic runoff layer. The particulate matter concentration change process under the action of different driving forces is solved through a mass conservation equation, a slope rainfall runoff analytical solution equation is combined, an improved Euler method is adopted for numerical solution, and accurate calculation of the urban pavement particulate matter transmission rate is achieved. According to the method, traditional empirical parameters are converted into variables with clear physical significance, the problems that an existing model is unclear in physical mechanism and low in prediction precision are solved, a scientific basis can be provided for urban runoff pollution load calculation and accurate prevention and control, and the method has the advantages of being clear in physical significance, high in calculation efficiency, good in prediction precision and high in engineering applicability.

The application discloses a multi-harmonic suppression method for a dual three-phase permanent magnet synchronous motor, and comprises the following steps: S1, a model of a dual three-phase permanent magnet synchronous motor driving system is established; a six-dimensional voltage vector is constructed through a switching state generated by a voltage source inverter, and a stator voltage vector is decomposed by adopting a vector space decomposition method to establish a voltage equation; S2, multi-source harmonic distortion characteristics are analyzed; current harmonic components caused by phase group asymmetry, non-sinusoidal distribution of counter electromotive force and nonlinearity of the inverter are respectively identified and analyzed; S3, a harmonic suppression controller based on an online neural network assisted linear extended state observer (ONN-assisted LESO) is designed; a super-local model is constructed to describe stator current dynamics; an auxiliary neural network compensator is introduced; a weight adaptive law is designed in combination with Lyapunov stability analysis, a forward Euler method is adopted to realize discretization control, and a voltage reference value is generated to realize real-time suppression of multi-harmonics. The application can effectively realize multi-harmonic suppression under different operating conditions, and meanwhile, fast dynamic response and robust current performance are maintained.

This invention discloses a flexible interconnection system with a nine-switch converter and its switching loss control method and device. The method first constructs a mathematical model of the nine-switch converter to obtain 27 voltage space vectors; secondly, it establishes the system... αβ A coordinate coefficient mathematical model is discretized using the forward Euler method to obtain a prediction model, and an unweighted coefficient value function is designed to accurately track the current. Then, a voltage vector is selected and a zero vector is inserted, and a fixed switching frequency switching sequence is designed. Finally, the voltage vector's action time is determined by duty cycle modulation, and the optimal voltage vector is periodically selected alternately. This invention effectively solves the problems of inconsistent switching frequencies, uneven losses, large current harmonics, and heavy computational burden in existing systems. By balancing power device losses, it extends device lifespan and improves system stability. It enables bidirectional flexible power interconnection between two three-phase power grids and ensures system operational stability and power quality.

The invention relates to the field of racing car dynamics optimization, and discloses an electric formula racing car dynamic performance optimization method and system, a storage medium and equipment. A Newton-Euler method is adopted to construct an eight-degree-of-freedom vehicle dynamical model including vehicle body longitudinal, transverse, yawing and roll degrees of freedom and four-wheel rotation degrees of freedom, and then a vehicle body mechanical equilibrium equation set, a four-wheel load calculation equation and a four-wheel slip rate and slip angle calculation equation are obtained; based on a car body mechanical equilibrium equation set, a four-wheel load calculation equation and a four-wheel slip rate and slip angle calculation equation, an optimal control problem is determined, the optimal control problem is converted into a nonlinear programming problem and solved, and an optimal racing car track driving control sequence is obtained; and setting particle vectors of vehicle parameters including wheelbase, wheel track and braking force distribution coefficient, and performing iterative optimization on racing track time by adopting a particle swarm algorithm. According to the method, the calculation complexity can be reduced, and the optimization efficiency is improved.

A numerical modeling method for an underwater complete axial symmetry space three-wave coupling sound field belongs to the field of nonlinear acoustics, and comprises the following steps: carrying out simple harmonic hypothesis on sound waves, and substituting the sound waves meeting difference frequency three-wave frequency matching conditions into a KZK equation to obtain a difference frequency three-wave coupling equation set; decomposing the equation set into a diffraction equation, a dissipation equation and a nonlinear equation by using a second-order Strong operator splitting method; a diffraction equation is solved by using a chasing method, a dissipation equation is solved by using an accurate analytical solution, and a nonlinear equation is solved by using an explicit Euler method; and setting boundary conditions, and calculating an underwater complete axial symmetry space three-wave coupling sound field. According to the method, a three-wave coupling sound field model is established based on a KZK equation, efficient solving of a three-wave coupling equation set is achieved by utilizing a second-order Strong operator splitting method and combining finite difference and an explicit Euler method, and the three-wave coupling sound field in the underwater complete axial symmetry space is accurately calculated. According to the invention, the calculation complexity is reduced, the calculation efficiency is improved, and the calculation result is accurate.

This invention discloses a simplified power point tracking (PPT) control method for NPC rectifiers, comprising: calculating the grid-side complex power S and the differential expression of the negative conjugate complex power based on the mathematical model of the three-level NPC rectifier and instantaneous power theory; discretizing the negative conjugate complex power at time k+1 in the dq rotating coordinate system using the forward Euler method; calculating the power error of the negative conjugate complex power under zero vector action at time k+1; performing preliminary vector pre-selection based on the sector where the power error is located; reducing the number of pre-selected vectors in each group in step four to four; cyclically calculating the predicted active and reactive power values ​​and the cost function J at time k+1, and determining the optimal vector. This invention simplifies the computational workload in the vector selection process of a three-level midpoint clamp rectifier by reducing polling pre-selection vectors, and introduces power point tracking error correction on the basis of traditional PI, thereby achieving accurate power point tracking control.

This invention discloses a model predictive control method, device, and medium for an electro-hydraulic servo system, relating to the field of electro-hydraulic servo model prediction technology. The method includes: acquiring data based on the electro-hydraulic servo system; defining a state variable vector based on the resultant force formed by the equivalent chamber pressure difference; discretizing the vector using the forward Euler method; constructing a piston force balance equation; updating the state variable vector data; setting the relationship equation between the valve core opening and the control voltage in the electronic control domain; updating the flow rate of the hydraulic cylinder into the upper and lower chambers; and reconstructing and updating the state variable vector. The method of this invention, through the combined use of the force balance equation in the mechanical domain and the compensation signal in the electronic control domain, allows the voltage change issued by the controller to be equivalent to direct control of the output force. Through the integrated fusion of static mapping functions and dynamic compensation functions, the compensated voltage drive signal can maintain ideal linearity in steady state and correct hysteresis errors in real time during dynamic changes.

The invention discloses a power system inertia and damping optimal estimation performance evaluation index construction method, and relates to the technical field of power system frequency stability control, and the method comprises the steps: S1, constructing a new energy high-permeability power system dynamic model; s2, constructing an optimal estimation performance index; wherein the step of constructing the optimal estimation performance index in the step S2 comprises the following sub-steps: S201, performing discretization processing on the dynamic model of the new energy high-permeability power system based on a forward Euler method to obtain a discretization observation model; s202, adding measurement noise based on the discretization observation model to establish a discretization observation model containing noise; s203, obtaining an information matrix in combination with maximum likelihood estimation; and S204, obtaining optimal estimation performance indexes of inertia and damping in the new energy high-permeability power system based on the information matrix, providing a theoretical performance reference for an inertia and damping monitoring algorithm of a power dispatching center, and improving reliability and assessability of frequency stability control of the power system.

The invention discloses a hybrid micro-grid control method based on MPC, and belongs to the technical field of power grid control, and the method comprises the steps: S1, building a state-space equation of a hybrid micro-grid based on a variable quantity representing the stability of the hybrid micro-grid and an influence variable influencing the stability of the hybrid micro-grid; s2, acquiring an output equation based on the variable quantity, and discretizing the state-space equation and the output equation based on a forward Euler method to acquire a prediction equation; and S3, constructing a performance index function of the MPC according to the prediction equation, solving the performance index function by taking the minimum value of the performance index function as a control optimization target to obtain a final value of a control variable, and controlling the hybrid microgrid based on the final value of the control variable. The problems of insufficient direct-current voltage support, dynamic coupling oscillation and steady-state power distribution imbalance are synchronously solved by considering the stability of both sides of alternating current and direct current, so that the technical problem that the stability of the hybrid microgrid is difficult to comprehensively improve in the prior art is solved.

The application discloses a cascaded large model robot motion planning method based on timing logic constraints, which comprises the following steps: a task planner receives user instructions and corresponding STL expressions, environment information, decomposes the user instructions and corresponding STL expressions, and obtains sub-tasks and corresponding STL expressions; whether the decomposed sub-tasks meet the logic constraints, time constraints and space constraints is detected by an STL checker; if yes, correct controllers are generated according to the sub-tasks; the generated correct controllers are integrated with a robot model, a Monte Carlo method is used to generate multiple groups of random parameters based on uncertainty factors, real environment disturbances are simulated, an Euler method is used to discretize and iteratively solve trajectories of the robot continuous kinematics equation, the trajectories are checked by the STL checker to make the trajectories meet the requirements of the user instructions, and finally correct trajectories are obtained. The application realizes user instructions containing space, time and kinematics constraints.

The invention belongs to the field of ocean devices, and provides a pile type fence structure load dynamic response model construction method, which comprises the following steps: obtaining engineering arrangement parameters of a fence structure, constructing a wave flow field near the fence structure based on a potential flow theory, and calculating the speed and acceleration of a water quality point; piles and connecting components are regarded as rigid structures, a rigid body dynamic motion equation is established, a netting system is regarded as a flexible structure, and a dynamic model of the netting system is established through a concentrated mass point method; hydrodynamic loads of the piles, the netting and the connecting components are calculated, and effective tension of the slender rod components is calculated; calculating the horizontal bearing capacity of the pile foundation to simulate pile-soil interaction; and finally, carrying out numerical solution on the kinetic equation by adopting a semi-implicit Euler method to obtain dynamic response results of pile bending moment, netting tension and node displacement. The multi-system coupling dynamic response characteristic of the pile type fence structure under the wave action can be comprehensively reflected, and the method is suitable for safety evaluation and engineering design of the fence structure.

The invention provides a magnetic source parameter inversion method and system based on a mixed direction oblique derivative Euler method, and belongs to the field of magnetic exploration. The aeromagnetic data is subjected to inversion calculation through a pre-constructed mixed direction tilt-Euler equation set, an initial Euler solution is obtained, and the mixed direction tilt-Euler equation set is determined in combination with mixed direction tilt gradient derivative transformation after three-dimensional Euler deconvolution equation vertical integration and second-order mixed partial derivative processing; screening the initial Euler solutions based on a mixed direction tilt gradient total horizontal derivative corresponding to the mixed direction tilt gradient derivative to determine an inversion solution; and performing direction combination on the inversion solution to obtain a magnetic source parameter prediction result of the to-be-explored area. According to the method, the credibility and the aggregation degree of a magnetic source parameter solution are remarkably improved, and the practicability and the reliability of Euler deconvolution in a complex magnetic anomaly environment are greatly improved.

The invention provides a hybrid robot dynamic modeling and friction parameter identification method. The hybrid robot dynamic modeling and friction parameter identification method comprises the following steps that a Newton-Euler method and a spiral theory are used for establishing a dynamic model considering active and passive joint friction for a hybrid robot; carrying out global sensitivity analysis on friction parameters of the hybrid robot by adopting a summation function variance and covariance decomposition method; an identification and verification circular trajectory of the hybrid robot is planned according to a quintic polynomial; the driving torque of a servo motor in the moving process of the robot is collected; and carrying out friction parameter identification on the hybrid robot by using a Gaussian quantum particle swarm algorithm. The method has the beneficial effects that the established model can accurately predict the driving torques under different configurations, and a reliable dynamic basis is provided for trajectory planning and real-time control of the robot.

The invention relates to an Euler method water drop collection coefficient effective area determination method comprising the following steps: modeling and dividing grids according to the geometric shape of an aircraft; a fluid mechanics model is selected, and a steady-state air flow field is obtained through calculation; establishing and solving an Euler method water drop motion control equation, and calculating water drop collection coefficient distribution according to the wall surface water drop volume fraction and the velocity vector; obtaining a water drop streamline and calculating water drop collection coefficient distribution according to streamline parameters; comparing the results of the water drop collection coefficients to obtain a preliminary effective region of the Euler method water drop collection coefficients; and recalculating the initial effective area by using a Lagrange method, and judging to obtain an Euler method water drop collection coefficient effective area. According to the method, the effective region of the Euler method water drop collection coefficient can be judged, and on the basis of the method, the water drop collection coefficient of the effective region adopts a calculation result of the Euler method, and only an invalid region needs to be independently calculated by using a Lagrange particle statistical method; compared with a Lagrangian particle statistical method, global calculation is faster.

The invention discloses a multi-scale hybrid modeling method for two-phase flow under a large vortex simulation framework, which couples an Eulerian method and a Lagrangian method, can carry out high-precision and low-calculation-cost simulation calculation on high Reynolds number and Weber number fuel oil atomization problems in an afterburner, and provides a reliable simulation tool for the optimization design of the afterburner.

The invention discloses an LCL grid-connected inverter midpoint potential adaptive prediction control method, and the method comprises the steps: carrying out the discretization of a three-level NPC type LCL grid-connected inverter based on a forward Euler method, and building a prediction model; secondly, constructing a value function including grid-connected current tracking, filter capacitor voltage, inverter side current and a neutral-point potential balance term, wherein the neutral-point potential balance term is weighted by a variable weight coefficient; according to the method, a model-free adaptive control theory is innovatively introduced, a dynamic data model between midpoint potential deviation and a weight coefficient is established online by using a tight-format dynamic linearization method, and an adaptive updating law of the weight coefficient is designed through real-time estimation of a pseudo-partial derivative. According to the method, complex working conditions such as current step change can be effectively handled, neutral-point potential fluctuation can be strictly limited within 1V without manually setting parameters, cooperative control of grid-connected current high-precision tracking and neutral-point potential balance is realized, and the robustness and dynamic and steady-state performance of a system are remarkably improved.

The application provides a robot dynamic error compensation method based on a capsule neural network, adopts Newton-Euler method to establish a robot dynamics model, and performs linearization and dynamics parameter identification; uses joint motion data as input to obtain predicted torque for model training by using the linearized dynamics model after the dynamics parameter identification, and calculates error between the predicted torque and actual torque; regards normalized parameters as vectors in a vector space, calculates inner products of the vectors to form a Gram matrix and converts the Gram matrix into a two-dimensional image; learns error between the predicted torque and the actual torque by using a capsule neural network, and obtains a trained capsule neural network; obtains real-time prediction error by using the trained capsule neural network, and compensates real-time predicted torque obtained by the linearized dynamics model after the parameter identification by using the real-time prediction error. The application realizes high-precision and adaptive dynamic error compensation.