58 results about "Differential 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 discloses a copper recovery processing system and method for flameless combustion of copper-containing sludge, and relates to the technical field of intelligent control. A distributed sensor network is deployed, multi-source combustion data in a combustion furnace are acquired in real time, a hybrid convolution-long and short-term memory network model is constructed, cross-modal feature fusion is performed on the multi-source combustion data, and the copper recovery processing system and method for flameless combustion of the copper-containing sludge are obtained. The method comprises the following steps: extracting a multi-dimensional combustion feature vector, correcting system parameters of a differential-algebraic equation on line based on the multi-dimensional combustion feature vector, solving a real-time system state variable after the system parameters are corrected, and constructing a constraint condition by using the system state variable. A multi-agent reinforcement learning model is constructed based on the multi-source combustion data and the multi-dimensional combustion feature vectors, dynamic combustion parameters are optimized in parallel by adopting a multi-agent depth deterministic strategy gradient algorithm, and the dynamic combustion parameters are sent to a combustion execution mechanism for combustion parameter updating; the stability and the environmental protection performance in the combustion process are obviously improved.

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.

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 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.

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 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.

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

The present invention belongs to the field of optoelectronic technology and relates to a method and system for evaluating the damage of a detector caused by moving laser irradiation. The evaluation method includes: determining the parameters of the moving laser and the parameters of the detector's structural material properties; constructing a transient solid heat transfer model of the detector; setting the physical field boundary conditions of the transient solid heat transfer model and performing mesh division; setting the solver parameters, specifically: inputting the moving laser pulse width and the moving laser frequency into a pre-trained linear neural network model and using the expression of the model to calculate the solver parameters; based on the solver parameters, solving the transient solid heat transfer model in the solver, and determining the thermal damage condition of the detector by calling the domain ordinary differential and differential algebraic equation module. If it is determined that the detector has been damaged, calculate the damage area and volume of the detector to obtain the spatial distribution of the damaged area of the detector.

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

The invention belongs to the technical field of thermal hydraulics, and particularly relates to a Modelica-based two-fluid six-equation and differential algebraic equation coupling system compiling and solving device and a Modelica-based two-fluid six-equation and differential algebraic equation coupling system compiling and solving method. Comprising a compiling stage function system and a solving stage function system. The method has the beneficial effects that the problem of coupling, compiling and solving of a two-fluid six-equation system and a differential algebraic equation system under a unified modeling framework based on Modelica is solved, and a compiling and solving device with complete functions is provided; the whole process compiling solution from topological structure generation, coefficient matrix assembly, time step size control, source term function calculation, matrix equation solution to convergence judgment based on the quality error of the two-fluid six-equation system is realized; the whole-process compilation solution from grammar semantic check, planarization processing, compilation analysis to nonlinear solution of the differential algebraic equation system is realized, and the real-time data communication and interaction of the two-fluid six-equation system and the differential algebraic equation system under the unified solution sequence planning are realized.

The present invention discloses a method, system, terminal device and storage medium for transient stability assessment of a multi-machine system based on a hyper-tangent plane. The method constructs a differential algebraic equation group of the multi-machine system according to the state quantity of the multi-machine system, calculates the equilibrium point and Jacobian matrix of the multi-machine system according to the differential algebraic equation group of the multi-machine system, and then determines a class of unstable equilibrium points and Jacobian matrices thereof. The hyper-tangent plane equation is calculated according to the Jacobian matrix of the class of unstable equilibrium points. The nonlinear characteristics of the multi-machine system are analyzed by the hyper-tangent plane equation and the fault trajectory to calculate the critical fault removal time of the multi-machine system, and the transient stability of the multi-machine system is evaluated according to the critical fault removal time, thereby improving the accuracy of the transient stability assessment of the multi-machine system, ensuring the stable operation of the multi-machine system, and solving the problem that the transient stability assessment result of the multi-machine system is low due to the lack of analysis of the nonlinear characteristics of the multi-machine system in the time domain simulation method.

A four-step method for identifying parameters of a lithium battery equivalent circuit model based on differential algebraic equations is disclosed. In the method, an equivalent circuit model of a lithium battery is selected and a differential algebraic equation is established. A loss function is constructed according to the equation and the voltage and current values at the terminals of the battery, and relevant constraint conditions and initial values of the identification parameters are determined. A system of ordinary differential equations is solved, the loss function is calculated according to the solution and the voltage and current values at the terminals of the battery, the partial derivatives of each independent variable of the loss function are calculated, and the identification parameter values of the next iteration are obtained by substituting the partial derivatives into the gradient descent method. The iteration is repeated until the minimum value of the loss function is obtained, and the volt-ampere characteristics and state of charge of the lithium battery are predicted according to the identification parameter values. This method establishes a mathematical model, constructs a loss function, and uses a gradient descent optimization method and a numerical solution method to identify the parameters of the lithium battery equivalent circuit model, which can fit the entire charging and discharging process, has a faster convergence speed, and has high accuracy in predicting battery performance.

The invention belongs to the technical field of thermal hydraulic calculation, and particularly relates to a regulating valve or stop valve actuating mechanism modeling method suitable for Modelica specifications. Comprising the following steps: representing a regulating valve or stop valve actuating mechanism model as a control type model which takes a target opening degree as an input interface and takes an actual opening degree as an output interface; constructing a valve action state judgment model; a valve opening calculation model is constructed, and the actual valve opening at the current moment is calculated according to the action state of the valve and the full-travel switching time; and an input interface of the execution mechanism model is connected with the control system model, so that the precise control of the opening degree of the valve and the simulation of the action performance of the valve under different control logics are realized. The method has the beneficial effects that the valve opening control modeling can be carried out under a Modelica-based modeling framework without taking the time step length as an input quantity, and the incompatibility of a valve opening control modeling method and a Modelica-based differential algebraic equation solving algorithm is avoided.

The invention provides a method for depicting a transient stability boundary of a multi-inverter series-parallel system based on reverse integration, and belongs to the field of electrical engineering. According to the depicting method, a circuit model of a network building type inverter, a circuit model of a network following type inverter and an infinite power grid series-parallel system and a circuit model of a network building type inverter virtual synchronous machine mathematical model are combined, a second-order differential-algebraic equation set of the series-parallel system is obtained through derivation, and system steady-state balance points are obtained and classified by further solving the equation set. And carrying out reverse integration on the I-type unbalanced stable point to obtain the transient stability boundary of the series-parallel system. The method is simple and visual, has a solid theoretical foundation, 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 series-parallel system.

The invention discloses a micro-grid linearization model order reduction method, system, equipment and medium, and belongs to the field of micro-grid stability analysis and control. Models of all elements in a micro-grid are obtained, a nonlinear differential algebraic equation set is established, a stable equilibrium point of the nonlinear differential algebraic equation set is solved, linearization processing is carried out, and a linearized differential algebraic equation set is obtained; solving a rightmost characteristic value by adopting a characteristic value algorithm, if the system is not stable, performing leftward translation transformation on the system to stabilize the system, generating a Lyapunov equation according to the translated system, solving a controllable and observable Gramb matrix by adopting a Krylov subspace algorithm, and performing order reduction on the translated system by adopting a balanced truncation method to obtain a stable system; according to the method, an existing balance truncation method is improved, the precision, the stability, the controllability and the observability of a system after order reduction are guaranteed, meanwhile, the Grubrum matrix can be efficiently solved, and the method is made to be suitable for an unstable system.

The invention relates to an inverter grid-connected parameter stability domain identification method and device based on bifurcation characteristics, and the method comprises the steps: building a generalized swing equation based on differential algebraic equations of different inverters; deducing a unified standard form and equivalent parameters suitable for bifurcation analysis; systematically analyzing boundary conditions of generalized saddle node bifurcation, Hopf bifurcation and homoclinic bifurcation, and constructing region division with different dynamic behaviors in a parameter space; and based on system balance points and manifold characteristics in different regions, and in combination with a Melnikov function analysis result, stability domains under inverter control parameters and electrical parameters are accurately identified. According to the method, a nonlinear dynamics principle is utilized, bifurcation boundary conditions of an inverter grid-connected system are deduced, typical areas with different dynamics structures in a parameter space are constructed, parameter stability domains under different operation working conditions are further identified, the multi-parameter stability problem of a complex system can be reduced to boundary judgment of a few key parameters, and the stability of the inverter grid-connected system is improved. And the stability domain identification efficiency and precision are greatly improved.

The embodiment of the invention discloses a hybrid simulation system prediction method and system. The method comprises the following steps: establishing a first deep learning network model used for fitting an atomic model of differential algebraic equation solution; establishing a second deep learning network model for fitting a causal relationship between sub-composite models and atomic models in the composite model and a causal relationship between event generation sequences between the atomic models; training the first deep learning network model and the second deep learning network model based on data generated by simulation of a continuous and discrete event hybrid system simulation specification; and performing cooperative reasoning by using the trained first deep learning network model and the trained second deep learning network model to obtain a prediction result. According to the embodiment, the accuracy of system simulation fitting is guaranteed, the prediction efficiency of system simulation is improved, a complex system can be predicted in advance while running, and data is efficiently accumulated for intelligent training.

A tractor-trailer system pose derivation method, a tractor-trailer system, and a computer-readable storage medium. The method includes: determining an initial pose state of a tractor-trailer system; obtaining a real-time position of the tractor of the tractor-trailer system, and determining the real-time position of the tractor as a target position; obtaining a linear speed and a steering rudder angle of the tractor by processing the initial pose state and the target position using a preset trajectory tracking controller; and obtaining a target pose state of the tractor-trailer system by processing the initial pose state, the linear speed, and the steering rudder angle using a preset differential algebraic equation solver. In this manner, the, the poses of the tractor-trailer system can be accurately deduced, thereby facilitating the application of autonomous driving technology in the tractor-trailer system.

The invention discloses a multi-stage separation process simulation efficient DLPT general solving method and system and application, and relates to the technical field of chemical process simulation, and the method comprises the steps: obtaining the initial condition of a multi-stage separation differential algebraic model; determining simplified physical property model parameters according to the initial conditions; performing iterative solution on the differential algebraic equation set based on the simplified physical property model parameters and an integral algorithm; and outputting a final calculation result. The efficient DLPT general solving method and system for simulating the multi-stage separation process and the application have the advantages that the PT algorithm is low in initial value requirement and wide in convergence domain, the inner-layer strategy and the outer-layer strategy are introduced, a simplified physical property model is used in the inner-layer integration process, calculation time consumption is greatly shortened, the inherent speed bottleneck problem of the PT algorithm is solved, and the calculation efficiency is improved. And the balance between convergence robustness and calculation efficiency is realized.

The invention discloses a virtual synchronous machine parameter optimization method and a related device, and belongs to the field of power system control parameter optimization, and the method comprises the steps: firstly obtaining a related model and parameters of a virtual synchronous machine, and building a differential algebraic equation representing the dynamic characteristics of a micro-grid before disturbance; then solving a stable equilibrium point, carrying out linearization processing on the differential algebraic equation at the equilibrium point to obtain a small-interference stability analysis model, and solving a characteristic value and a damping ratio of the small-interference stability analysis model; determining a micro-grid model after large disturbance and disturbance removal, and performing transient stability evaluation; and finally, constructing an objective function and a constraint condition of parameter optimization considering small interference and transient stability, and obtaining an optimized inertia coefficient and a voltage integral coefficient. In addition, the damping coefficient and the reactive droop coefficient are determined according to the requirements of the micro-grid for the variation range of the frequency and the voltage and economic operation. According to the method, the micro-grid can be ensured to have relatively good small-interference stability and transient stability at the same time.

The application provides a power supply system key equipment fault diagnosis method based on digital twinning, first, according to expert knowledge and a design scheme, modeling of power supply system key equipment is carried out, fault mode analysis is carried out, and a fault behavior twinning model is established, and experimental results prove that the twinning modeling method is effective, and the expected result is better adapted. Then, by adding random noise, the actual operation is better simulated, and the twinning modeling of the fault behavior dimension is successfully realized. The application also takes the data set generated by the fault behavior twinning model as the basis, analyzes the transient stability of the system key equipment, obtains a differential algebraic equation capable of describing physical information, combines the differential algebraic equation with a neural network loss function, and the construction of PINN is completed with a relatively ideal effect, and after 400 times of training, the training error reaches the order of magnitude of 10 ‑3 .

The application relates to the technical field of electric propulsion digital twin simulation, and discloses an electric propulsion digital twin simulation data reduction method, which comprises the following steps: acquiring simulation data of electric propulsion plasma; based on the simulation data, snapshot data is extracted in a grid unit of a calculation domain; singular value decomposition is performed on the snapshot data, a reduced orthogonal basis is established, and reduced data representation is obtained through projection; based on a plasma fluid control equation, a semi-discrete ordinary differential algebraic equation group is constructed, and a coefficient matrix of a reduced model is determined through least square fitting; real-time simulation of an electric propulsion digital twin system is performed by using the reduced model, and field data is output. According to the application, the calculation precision and the simulation result obtained by PIC / MCC simulation are in the same order of magnitude, the calculation time reaches the level of seconds, and the real-time simulation demand can be met.