50 results about "Euler method" patented technology

A soft tissue modeling method in a virtual operation based on biomechanical characteristics comprises the following steps: 1) setting a mass point spring system, and establishing a kinetic equation for each mass point; 2) moving least square method approximation of a displacement field; 3) simulation updating: calculating a new displacement field by using MLS approximation, and ensuring physical constraints; 4) solving a kinetic equation, and solving the equation by using an implicit Euler method to obtain system response changing along with time; and (5) iteration and adjustment are carried out, an implicit Euler method is used for solving the equation, and system response changing along with time is obtained. According to the method, the biomechanical characteristics of the soft tissue are effectively simulated by adding multiple functional springs, then the MLS method is integrated into the mass point spring model, the capacity of the model for processing complex deformation and large displacement events is enhanced, meanwhile, the overall numerical stability and accuracy are improved, and the method is suitable for large-scale popularization and application. And the established soft tissue model is more suitable for the requirements of a virtual operation system.

The invention relates to the technical field of consumption behavior analysis, in particular to a user consumption data analysis method and system based on big data, and the method comprises the following steps: collecting and sorting the consumption data of a user, including purchase time, price, preference and product availability, calculating a correlation coefficient of the purchase time and the price, and calculating the consumption data of the user; and analyzing the correlation degree of the preference data and the product availability to obtain a correlation evaluation result. According to the invention, the consumption model is constructed through the differential equation, and the consumption behaviors at different time points are simulated through the Euler method, so that the consumption trend change can be predicted in a complex market environment, the flexibility and adaptability of data analysis are improved, the formulating and adjusting capabilities of the market strategy are effectively enhanced, and the market experience is improved. The method plays an important role in mastering consumption peaks and low ebbs, helps enterprises to occupy advantages in fierce market competition, optimizes resource allocation, and improves customer satisfaction and loyalty.

The invention discloses a modeling method of an SCR (Selective Catalytic Reduction) denitration system mechanism hybrid prediction model based on Transform. Feature extraction is carried out on the collected data, a reaction kinetic equation is constructed, an Euler method is adopted for solving, and unknown model parameters are reserved; a section of working condition stable data is selected from the collected data and imported into a mechanism model, optimal model parameters are found, the mechanism model of the SCR denitration reaction is obtained, and the A side outlet flue concentration and the B side outlet flue concentration are calculated through the model; a Transform model is trained to compensate the SCR system mechanism model, and the compensated SCR system mechanism model serves as real-time soft measurement values output by the A side and the B side; input variable selection is carried out on all-condition data, A-side and B-side outlet flue concentrations obtained by the mechanism model in real time and outputs at the first two moments are included into an input variable set, and time delay processing is carried out on input variables; and the mechanism models of the A-side flue and the B-side flue are connected in series with a Transform model, the Transform model needs to be imported into the output of the mechanism models in real time, and finally the SCR denitration system hybrid prediction model is obtained.

The invention discloses a preset performance convex online model prediction unmanned ship trajectory tracking control method, belongs to the technical field of trajectory tracking, is used for unmanned ship trajectory tracking control, and comprises the steps of unmanned ship modeling, discretization processing on a continuous time-varying nonlinear model by using a preceding Euler method, and prediction control by using a linear time-varying model. The processing involves a non-linear state-space equation; optimizing an objective function, converting predictive control into quadratic programming, establishing constraint conditions required by predictive control, and establishing a specified time discrete preset performance function through predefined time control so as to rewrite the constraint conditions; and resolving the objective function to obtain the latest position under the trajectory of the unmanned ship. According to the method, the continuous nonlinear model is discretized through the previous Euler method to reduce the calculation complexity, the specified time discrete preset performance function is constructed through the predefined time control method, and the precision requirement of trajectory tracking is met under the specified time preset performance of the tracking error.

The invention discloses an alternating current optimal transmission switching relaxation problem solving method based on a two-stage dynamic trajectory and pseudo-transient continuity. The method comprises the following steps: constructing an alternating current optimal transmission switching relaxation model; constructing an augmented quotient gradient system corresponding to the alternating current optimal transmission switching relaxation model; randomly selecting an initial point x0, and performing integral augmentation on the quotient gradient system from x0; carrying out integral iterative calculation on the augmented quotient gradient system by adopting a pseudo-transient continuous iterative formula based on an Euclidean Euler method; when the target function descent rate of the trajectory of the augmented quotient gradient system is smaller than 0.001% / step, integration is stopped, and the termination point at the moment is recorded as x *; x * is used as an input point, an IPOPT solver is adopted to solve the alternating current optimal transmission switching model, and an optimal solution is obtained through solving. According to the method, a dynamic method and a static method are combined, respective advantages of the two methods are taken, a pseudo-transient continuous iteration formula is provided in the integration process of the augmented quotient gradient system, and the optimal transmission switching relaxation problem which is difficult to solve by the power system can be quickly solved on the basis of ensuring the solution robustness.

The invention discloses a fluid-solid coupling numerical simulation method for coupling surface water and soft soil roadbed soil, which comprises the following steps of: setting simulation time and time step length, and inputting acquired surface water data and physical property parameters of roadbed soil into a simulation model; the method comprises the following steps: establishing a coupling function equation of surface water and soil: describing the movement of the surface water through a Stokes equation containing boundary conditions, describing the soil through a Biot equation, and coupling the Stokes equation and the Biot equation through interface conditions to obtain a coupling system; constructing a Robin boundary condition, and reconstructing and decoupling the coupling system through a Lagrange-Euler method; when the simulation time is up, simulation is ended, and deformation displacement, seepage flow pressure and seepage flow speed of the roadbed are output and used for judging the stability of the roadbed. The method solves the problems that stability judgment according to the coupling effect of the surface water and the soft soil roadbed is difficult, and a large number of resources are consumed.

The object of the present invention is to provide a method for predicting the discrete particle trajectories of a pipeline centrifugal separator based on a surrogate model, which comprises the following steps: planning the experimental matrix of the structural parameters and flow field distribution of the pipeline centrifugal separator; obtaining the corresponding matrix between each structural parameter and flow field characteristic parameter according to the simulation experimental data; conducting a sensitivity analysis of the input variables, selecting a modeling technique, and constructing a surrogate model for the key input parameters and response values; comparing the results of the surrogate model with the experimental data; constructing a force model for discrete particles in the swirling flow field; establishing a transient motion trajectory equation for discrete particles by using the Euler method, and coupling and solving the flow field calculation model and the particle force model to obtain a discrete particle motion prediction model. The present invention can predict the motion trajectories of discrete particles in the separator under conditions of different physical property parameters, different structural parameters, and different flow parameters, so as to provide guidance for the structural design and application of the pipeline centrifugal separator.

The invention discloses a series industrial robot external force estimation method, and the method comprises the following steps: S1, constructing a series industrial robot kinetic equation model incorporating a kinetic residual error through a Newton-Euler method; s2, fitting the dynamic residual error and noise of the robot by using a variational approximate Gaussian process; s3, constructing an external force estimation discrete state equation; s4, constructing an adaptive Kalman filter; and S5, solving the external force through Kalman iteration. The external force applied to the robot can be estimated, the external force and collision applied to the robot can be detected under the condition that the robot is not provided with a six-dimensional force or torque sensor, the detection precision and response speed of external force estimation are improved, and the method can be used for industrial scenes such as robot assembly and polishing.

The invention discloses a battery network state calculation method and device, equipment, a medium and a product, and relates to the technical field of battery network state calculation. The method comprises the following steps: firstly, constructing a dynamic reconfigurable network of a battery system based on a topological structure of the battery system; dividing the dynamic reconfigurable network into a plurality of sub-networks; then respectively constructing a state space equation of each sub-network; and then solving the state-space equation of each sub-network based on an improved Euler method to obtain the state quantity of each sub-network at different time steps. According to the method, the dynamic reconfigurable network is divided into a plurality of mutually independent sub-networks, the overall state calculation of the battery network is converted into the state calculation of the plurality of sub-networks, the calculation amount and the calculation complexity are effectively reduced, the Euler calculation of two stages is used for evaluation, and the accuracy of a numerical solution is improved.

The present invention discloses a method for predicting the trajectory tracking control of an unmanned ship using a preset performance convex online model, which belongs to the field of trajectory tracking technology and is used for unmanned ship trajectory tracking control, including modeling an unmanned ship, discretizing a continuous time-varying nonlinear model using the preceding Euler method, using a linear time-varying model predictive control method to process nonlinear state space equations; optimizing the objective function, converting the predictive control into quadratic programming, establishing the constraints required for the predictive control, establishing a preset performance function discrete at a specified time through predefined time control, thereby rewriting the constraints; solving the objective function, and obtaining the latest position under the trajectory of the unmanned ship. The present invention discretizes the continuous nonlinear model through the preceding Euler method to reduce the complexity of the calculation, and uses the predefined time control method to construct a preset performance function discrete at a specified time, so as to meet the accuracy requirements of trajectory tracking under the preset performance of the specified time of the tracking error.

The invention provides an anisotropic large-scale structure attitude adjustment trajectory planning method which specifically comprises the following steps: firstly, carrying out dynamic modeling on an attitude adjustment mechanism by adopting a Newton-Euler method so as to calculate driving force of each shaft of a positioner during attitude adjustment of a large-scale structure; dividing the attitude adjustment track into an acceleration section, a constant speed section and a deceleration section, fitting the attitude adjustment track by using a quartic polynomial, and calculating track parameters of the large structure in different directions; and finally, constructing a positioner driving force and speed constraint model, and performing attitude adjustment duration search by adopting a dichotomy, thereby improving the efficiency of attitude adjustment of the large-scale structure. According to the method, different time parameters (the proportion of a constant-speed section) are adopted for planning the motion trails of the large-scale structure in different directions, the performance of a servo control system can be brought into full play, and therefore the attitude adjustment efficiency of the large-scale structure is improved.

The invention belongs to the technical field of automatic driving automobile speed tracking, and particularly relates to an automatic driving automobile speed tracking cooperative control method based on hierarchical MPC and fuzzy PID, comprising the following steps: S1, constructing a longitudinal dynamic model of an automatic driving automobile; s2, designing a fuzzy rule; s3, obtaining a discrete system state equation by using a forward Euler method; s4, determining that the output of the system at the future moment is expressed in a matrix form; s5, converting an MPC problem and a quadratic programming problem; s6, the execution control layer converts the expected acceleration into throttle valve and brake master cylinder pressure control quantity through fuzzy self-adaptive PID; and S7, switching logic is adopted to judge driving / braking control, and speed tracking control is carried out. According to the method, buffeting can be effectively suppressed on the premise of ensuring that the system can reach a stable state, high robustness to external disturbance is achieved, and speed tracking of the self-driving automobile is ensured.

The invention relates to the technical field of aero-engine transition state characteristics and control process temperature calculation, in particular to a cooling-considered aero-engine transition state turbine rotor and stator temperature calculation method. An independent differential equation is established by introducing a hot side fuel gas and cold side cooling air double-heat-source model, and the method is suitable for an aero-engine scene with a complex cooling structure; a lumped parameter method is adopted to reasonably simplify a three-dimensional heat conduction equation, on the premise that the engineering precision of a component with the small Bi number is guaranteed, temperature distribution is simplified into a uniform field, the calculation dimension is remarkably reduced, in combination with an explicit Euler method numerical integration method, rapid discrete solving of a differential equation is achieved, the real-time requirement of an airborne model for transition state calculation is met, and the calculation efficiency is improved. And the time step length is adaptively adjusted to guarantee the numerical stability. By outputting the rotor / stator temperature of the turbine in real time, the dynamic heat exchange effect of the metal component and the airflow in the transition state can be accurately evaluated, and engine control law design and stability optimization are supported.

The invention discloses a multi-vector model prediction control method based on incremental global optimization, and the method achieves the control of a permanent magnet synchronous motor through the following steps: carrying out the discretization of a current state equation through employing an Euler method, and obtaining a current prediction model; a virtual vector with a harmonic plane component being zero is adopted as a vector control set, and a value function is set as the difference sum of squares of the predicted current and the reference current; subtracting the prediction current equations of two adjacent periods to obtain an incremental current prediction equation, and enabling the prediction current to be equal to the reference current to obtain an incremental voltage prediction model without a flux linkage item; selecting a synthetic reference vector according to the vector set; carrying out duty ratio distribution on the selected voltage vector scheme; and updating the value function and obtaining a global optimization vector scheme after duty ratio distribution. The method improves the robustness of the system, reduces the calculation amount, improves the prediction precision of the system, can be popularized to the motor control of an N * 3 phase structure, and is wide in application range.

The present invention discloses a parallel simulation method for an electrified power system based on the improved Euler method. A large-scale electrified power system contains a large number of power electronic switching devices. Such a high-order nonlinear system greatly increases the computational amount within a single simulation step. Therefore, it is necessary to decouple the entire system to achieve parallel simulation. The present invention establishes a state-space equation describing the coupling relationship of subsystems for the topological structure of passive components at the connection of converters to the grid, discretizes the AC inductor current and DC capacitor voltage of the converter based on the improved Euler method, and constructs an adjoint equivalent circuit of the discrete equation. The present invention can eliminate the delay between the equivalent circuit and the global solution of the system and achieve high-precision delay-free parallel simulation.

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 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.

This invention provides a robotic arm pose tracking control method for moving targets, relating to the control of autonomous moving bodies in three-dimensional space and the field of robotics. The control method includes: establishing the second-order pose dynamics equation of the target rigid body according to the Newton-Euler method; establishing the second-order pose dynamics equation of the robotic arm end effector according to the Lagrange equation; obtaining the relative pose dynamics equation based on the second-order pose dynamics equations of the target rigid body and the robotic arm end effector; and designing a robust adaptive controller for the relative pose dynamics equation, enabling the robotic arm end effector to complete the pose tracking control task of the moving target rigid body.

The application belongs to the technical field of hybrid electric propulsion aircraft, and discloses a modeling method, system and terminal for an electric propulsion aircraft power conversion system, four working modes of parallel power converters are determined; the circuit is discretely linearized by using a binary resistance method, and a discrete linearization model of boost and bidirectional DC / DC converters is constructed; node voltage transient equations are listed and written, and the electrical coupling characteristics of the parallel circuit are expressed by state variable coupling; the node voltage transient equation and the electrical coupling characteristic expression are solved by using a numerical method, a matrix equation is obtained, and iterative calculation is completed, and then the mathematical model of the electric propulsion aircraft power conversion system is obtained, and the working state simulation of the converter is realized. The application is based on linear discretization of the circuit and electrical state decoupling, and uses an implicit Euler method to solve the rigid differential equation, so that the accuracy and stability of the solution are obviously improved, and the application has good applicability. The application is supported by a master's postgraduate practice and innovation ability cultivation fund of Northwest Polytechnic University.

The invention provides a water drop collection coefficient calculation method based on an Euler method streamline, and the method comprises the steps: carrying out the modeling of a simulated aircraft part, and carrying out the grid division of a calculation domain; setting boundary conditions, and solving a steady-state air flow field; establishing a steady-state non-conservation form water drop momentum equation by using an Euler method to obtain steady-state water drop velocity field distribution; reading each surface node of the wall grid of the aircraft component, judging the surface node of a water drop impact area according to the water drop velocity field, and solving along the reverse direction of the water drop velocity by taking the node coordinate of the impact area as a starting point and taking the far-field boundary of the computational domain as an end point to obtain a water drop streamline; and sequentially calculating water drop collection coefficients of the wall grids according to the water drop streamlines, and outputting a water drop collection coefficient distribution result of the aircraft component. Compared with a traditional Lagrangian method, the method does not need to determine a water drop release position, and has better applicability and calculation efficiency on a complex surface; compared with a traditional Euler method, the calculation convergence is better, and the calculation of the water drop collection coefficient is more accurate.

The invention discloses a robot friction torque online prediction method and device and a computer readable storage medium, for a to-be-identified joint type series industrial robot, according to the embodiment of the invention, a robot kinetic model considering friction is established through a Newton-Euler method, and after the kinetic model is linearized, the friction torque of the to-be-identified joint type series industrial robot is predicted. Designing an excitation track by using five finite Fourier series, collecting joint motion data of the robot under the excitation track to establish a regression equation set, solving the regression equation set to obtain an integral kinetic parameter to be identified, and calculating the friction torque of the robot on line according to the integral kinetic parameter to be identified. The friction torque of the robot can be predicted on line.

The invention discloses a transverse control method for an automatic driving automobile with self-adaptive time domain parameters at different automobile speeds, and belongs to the technical field of transverse control of the automatic driving automobile. Constructing a nonlinear state equation based on the transverse dynamic model; performing first-order Taylor expansion on the starting point of the nonlinear state equation to construct a linear state space expression; performing discretization processing on the linear state space expression by using a forward Euler method to obtain a discretization model, and constructing a target function; optimizing the objective function by introducing a relaxation factor; obtaining a quadratic programming problem through the discretization model and the optimized target function, and setting the constraint of the quadratic programming problem; and a time domain parameter adaptive controller is constructed, and an optimal control time domain and an optimal prediction time domain are obtained by using a multivariable control strategy. According to the invention, the accuracy of the self-driving automobile at a low speed is ensured, the stability at a high speed is also improved, and the driving safety of the automobile at different speeds is ensured.

The application discloses a complex system simulation solving method based on a hybrid gradient search, and aims at the high-performance simulation solving demand of a system model under a mixed modeling strategy of an explicit mechanism and an implicit model. Under a mechanism description specification based on data and mechanism mixing, three main steps of an automatic optimization step of a solving path based on constraint qualitative information, an automatic transformation step of a differential term based on a robust Euler method and a gray-box system solving step based on a hybrid gradient search are adopted to adaptively establish a solving path of a system-level mechanism model, and high-precision gray-box solving guarantee is provided for a simulation task of the mixed modeling strategy.

The invention discloses an automobile driver dummy collision analysis system based on a six-dimensional force sensor, which relates to the field of dummy collision analysis and comprises the six-dimensional force sensor, a processing module, an optimization positioning module, an assessment map module, a model construction module and an early warning module. The method comprises the following steps: performing synchronization and tensor construction analysis on a force signal, a torque signal, a temperature signal and a vibration signal to obtain a dynamic net feature tensor, constructing a coupling equation to perform topological derivative analysis to obtain a damage hot spot coordinate and multi-dimensional potential energy topological derivation distribution, and creating a partial differential equation model of the neck injury to obtain a partial differential model of the neck injury. The method comprises the following steps: carrying out time discretization through an implicit Euler method, analyzing to obtain accumulated potential energy extension damage energy of each area, carrying out transient impact vibration extreme risk grade analysis, extracting contour surfaces, carrying out stereoscopic three-dimensional damage topology analysis to obtain a stereoscopic three-dimensional damage topology visual map, generating corresponding signals, and carrying out neck injury risk judgment based on the signals. And the risk level of the driver dummy can be accurately judged.

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.

The invention relates to the technical field of aviation cockpit thermal environment control, in particular to an aviation cockpit thermal environment control method and device, electronic equipment and a medium. The method comprises the steps that when it is detected that an aircraft cockpit environment control system is started, temperature distribution parameters of a front preset number of discrete nodes of an aircraft cockpit in a target attention time period are determined, and the temperature distribution parameters of all the discrete nodes are obtained according to a preset differential equation and an initial value thereof; carrying out difference solution on a preset heat transfer equation by adopting an Euler method and then carrying out fitting iteration; and controlling the temperature of the aircraft cockpit according to the temperature distribution parameters of the predetermined number of discrete nodes so as to enable the temperature of the aircraft cockpit to accord with preset standard temperature distribution. The problem that an existing cabin temperature numerical value solving technology is large in error and accurate is solved, and therefore the purpose of improving the cabin thermal environment control precision is achieved.

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.