370results about How to "Reduced simulation time" patented technology

The invention provides an active reliability analyzing and evaluating method for highly-reliable mechanical products. The active reliability analyzing and evaluating method for the highly-reliable mechanical products includes: firstly, establishing ultimate state functions of mechanical products, utilizing a Monte Carlo simulation method to produce sample points conforming to parameter distribution, utilizing a Kriging meta-model to simulate the ultimate state functions, improving simulation precision and confirming an optimal sampling radius by automatically updating DOE (design of experiment), constructing important sampling density functions, producing random sample points through the important sampling density functions, updating the DOE continually, then extracting radius random sample points obeying chi-square distribution, confirming failure probability and failure coefficient of variation of the mechanical products, and limiting whether updating finishes or not by the failure coefficient of variation so as to obtain reliability of the mechanical products finally. The active reliability analyzing and evaluating method for the highly-reliable mechanical products has the advantages of high efficiency, good robustness and high simulation precision, comprehensive design and analysis of rail wear life and reliability to spatial mechanisms are achieved, and the active reliability analyzing and evaluating method for the highly-reliable mechanical products is significant to reliability design technology engineering of complex mechanisms of aerospace equipment.

A significant improvement over current methods for co-simulation of the hardware and software components of embedded digital system designs is provided. The present invention integrates the hardware and software components of a system design into a single unified simulation environment. The unified simulation environment and the various component models of the system design are created in a high level general purpose programming language. This allows inter-component communications and communications with the unified simulation environment to be carried out through the use of function calls, which significantly increases the overall simulation speed. Additionally, the unified simulation environment runs as a single process, which significantly improves debugging capabilities. Furthermore, the present invention employs a higher level of abstraction than conventional simulation environments and thereby significantly increases simulation speed while moving away from the detail saturated event driven simulations of the past.

The invention discloses a wind power plant parameter identification and dynamic equivalence method based on operation data, comprising the following steps of a) performing recognition on wind generation set control model parameters based on testing data, b) combining with operation data and choosing characteristic variables reflecting the wind generation set and the wind power plant under influence and utilizing the improved fuzzy K average value dynamic clustering algorithm to perform cluster division, c) performing network simplification and parameter optimizing to obtain a wind power plant dynamic equivalence model based on global optimal position mutation particle swarm algorithm, and d) under disturbance input, comparing the wind power dynamic equivalence model with the detailed model dynamic respond to verify the validity of the equivalence model. The wind field dynamic equivalence model constructed by the invention can accurately reflect the dynamic characteristics of grid-connection points of the wind plant and have important construction application values, and can be used in the analysis of the stability of the double-fed wind power plant access power system and provide theory support for the programming and operation scheduling of the wind power plant power system.

Methods and apparatuses to design and analyze digital circuits with time division multiplexing. At least one embodiment of the present invention efficiently models subsystems connected by a TDM channel by introducing equivalent delays in the connections for the subsystems, where the delays are determined according to the upper bounds of the delays caused by the TDM channel. The TDM channel is modeled with its equivalent delays. Thus, a transformation tool is allowed to take into account the original constraints and time budgeting of the sending subsystem and the receiving subsystem. The problem of asynchronous clock domains is eliminated; and, simulation time of the multiplexed circuit is also improved. In some embodiments of the present invention, multiple TDM slots are assigned to a particular signal to reduce the equivalent connection delay caused by the TDM channel for the particular signal. In some embodiments of the present invention, timing simulation is performed using the equivalent delays to avoid the simulation of the TDM hardware; and, the simulation time step does not have to be reduced due to asynchronous clock, resulting in reduced simulation time.

The invention discloses a modular multilevel converter (MMC) topology converter efficient electromagnetism transient state simulation method. The method comprises the following steps: (1) building a thevenin equivalent circuit of a submodule and acquiring the hevenin equivalent circuit of a series subnodule, (2) opening power system computer aided design (PSCAD) and operating Fortran script editing user-defined module, (3) replacing at least one submodule by using the user-defined module, (4) using status bit to show insulated gate bipolar transistor (IGBT) status in the user-defined module of the PSCAD, (5) and figuring submodule capacitor voltage and submodule current by using a difference equation. The method reduces the number of nodes of a MMC topology converter model, and is quick in simulation speed and high in efficiency.

The invention relates to a method for macrosegregation numerical simulation of a casting, aiming at solving the problems of long computation time, low precision and unsuitability for predication of castings with large size or complex shapes in the traditional macrosegregation. The method comprises the following steps of: performing mesh generation on a selected dendritic crystal growth microcosmic computation field; computing dendritic crystal growth shapes during alloy solidification under different maximum nucleation densities from a microcosmic scale, and outputting a solid phase fraction-average dendritic crystal solid phase feature diameter curve; performing macro-scale mesh generation on the casting; computing a mass, momentum, energy and composition conservation equation from a macrocosmic scale; computing a solid phase fraction by using a Newton downhill method; and computing a pasty zone permeability model from a macrocosmic scale by adopting a linear interpolation technologybased on the solid phase fraction-average dendritic crystal solid phase feature diameter curve under a given nucleation density. The method disclosed by the invention is suitable for macrosegregationnumerical simulation in sand casting and metal mold casting of various sizes and complex shapes.

The invention provides a small interference stability simulation method of an electric power system, which can effectively utilize resources of a plurality of CPUs or a multi-core CPU processor in a computer, thus greatly improving the simulation efficiency. The method comprises: first, calculating the number of searching points of characteristic values, and automatically assigning calculating tasks with certain searching points of the characteristic values for every CPU core according to the number N of the CPU cores; then, calling fork( ) function under a linux system to generate N courses,and simultaneously calling the corresponding CPU core to independently execute the calculation of a searching point set by all sub-courses, thus realizing concurrent computation. After all the sub-courses complete the calculation, computing results of all the sub-courses are collected by main program for outputting the results.

The invention discloses a numerical integration method for electric power system full dynamic simulation, combining a fixed-step trapezoidal integration method and a variable-step Gear integration method organically in the full dynamic simulation. In the method, the fixed-step trapezoidal integration method, a differential equation of a dynamic element and an algebraic equation of power network are adopted to carry out iterative solution in a mechanical and electrical transient state process of the electric power system full simulation; in the method, the variable-step Gear integration method, the differential equation of the dynamic element and the algebraic equation of the power network are adopted to carry out simultaneous solution in a medium and long-term dynamic process. The fixed-step method and the variable-step method are switched automatically according to a certain strategy in the simulation. The method integrates the advantages of the two original numerical integration methods, thereby overcoming the defect of low calculational efficiency resulting from too small step in the simulation of mechanical and electrical transient state process of the electric power system of the existing full dynamic simulation program while ensuring numerical calculation stability and calculation accuracy.

A method for accelerating hardware simulation is presented wherein cycle based simulations of digital system designs are generated by raising the level of abstraction in a hardware simulation environment. Behavioral models of the digital system components are created in a high level general purpose programming language. Function calls created in a high level general purpose programming language provide a transaction based communication interface. During a simulation of the system design, the behavioral models communicate with each other through the transaction based communication interface. Additionally, the behavioral models employ an execute and update method of instruction processing that generates cycle accurate information for the simulation.

Methods for improving the accuracy and performance of large complex circuit simulations including; special processing of clock structures, minimizing repetitive simulation of identical structures, partitioning designs into sub-systems for use by one of a variety of matrix inversion techniques, row partitioning matrices for parallel solving, applying two stage Newton-Ralphon's method and iteratively selecting one of a number of serial and parallel matrix solvers to perform circuit simulation.

A method for simulating FPGA includes configuring message parameter with feature character in advance and storing said feature character in file, fetching file to obtain message parameter for automatically generating excitation message inserted with corresponding feature character outputting excitation message through interface module or receiving response message through FPGA logic module to be tested, comparing said messages based on feature character and outputting compared result.

The invention discloses an implement method of parallel fluid calculation based on an entropy lattice Boltzmann model, and provides a parallel implement mode of the entropy lattice Boltzmann model based on the GPU of a mainstream video card nVIDIA in current general calculation territory. The fact that ELBM simulated time is shortened by one third than the simulated time on a CPU is achieved by measuring the speed-up ratio of fluid parallel calculation and comparing the performance index of lattice number updated per second, and applying the CUDA on the GPU of the nVIDIA video card. A method of directly approximately solving a parameter alpha is more effective than an iterative method, namely, and time can be reduced by 31.7% averagely. The implement method of the parallel fluid calculation based on the entropy lattice Boltzmann model can use hardware resources of the system fully, and verifies the parallel calculation mode of the entropy lattice Boltzmann model from the actual operation level, and therefore efficiency of the whole parallel fluid calculation is improved obviously.

The invention belongs to the technical field of surface-mounted permanent magnet synchronous motors, and provides an improved permanent magnet angle cutting method for the problem of reducing cogging torque. A cogging torque expression is deduced on the basis of an energy method and Fourier decomposition and a factor relationship of affecting the cogging torque is confirmed; and a fourier coefficient of residual magnetism square of a permanent magnet after angle cutting is deduced on the basis of radial magnetization of the permanent magnet, an optimal determining method of an angle cutting length proportion coefficient is provided, and the problem of minimization of the cogging torque is converted into solving of a minimum value of a secondary function. According to the method, the simulation time of the motor can be shortened while the calculation accuracy is ensured and the cogging torque of the motor is reduced.

The invention provides a sparse matrix LU decomposition method based on a GPU. The sparse matrix LU decomposition method includes the following steps: A, building a to-be-simulated circuit matrix of a circuit network on a CPU, and performing preprocessing and rarefaction on the circuit matrix; B, selecting a computing platform for processing a sparse matrix LU according to preprocessing results; C, performing decomposition on the sparse matrix LU through the GPU if the computing platform which is used is the GPU; D, performing back substitution solution on values of non-zero elements in the sparse matrix LU through the CPU so as to complete decomposition of the sparse matrix LU. According to the sparse matrix LU decomposition method, the computing platform can be selected automatically according to the number of floating-point operation times in decomposition, the task on the CPU and the task on the GPU can be distributed reasonably, coordinated operation of a plurality of threads on the GPU is guaranteed, and therefore the computing speed is improved and circuit simulation time is shortened.

The invention discloses a method for calculating the electromagnetic vibration noise of a motor, which comprises the following steps: calculating the distribution of the electromagnetic force densityof the motor according to the operation condition of the motor, and calculating the static deformation and the natural frequency of the motor respectively; according to the distribution of the electromagnetic force density, the electromagnetic resultant force on the stator teeth of the motor is calculated, and the time-space harmonic of the electromagnetic resultant force is calculated. The frequency response function of the motor structure corresponding to each vibration mode is calculated according to the natural frequencies of each vibration mode corresponding to each spatial order of the electromagnetic force, and the transfer function of the motor mechanical structure is calculated according to the static deformation function and the frequency response function. The vibration displacement of the motor surface is calculated according to the time-space harmonics and the transfer function. The modal acoustic radiation efficiency of the motor housing is obtained, and the electromagnetic vibration noise of the motor is calculated according to the modal acoustic radiation efficiency and vibration displacement. In the process of analyzing the vibration and noise of the motor, the invention ensures that the calculation accuracy meets the precision requirement, and reduces the calculation amount to avoid consuming a large amount of calculation resources.

The invention discloses a method for carrying out integrated testing on an intelligent driving vehicle. The method comprises the following specific steps: (1) realizing a model in-loop simulation testunder a virtual test scene for an intelligent vehicle control strategy and algorithm; (2) realizing a software in-loop simulation test under a virtual test scene for a code generated or handwritten by the model; (3) downloading the model code to the target hardware to realize hardware in-loop simulation test under the virtual test scene; (4) mounting the controller on the intelligent vehicle to realize vehicle in-loop simulation test under the virtual test scene; and (5) mounting the controller on the intelligent vehicle to realize real vehicle test under a real scene, wherein the test scenein the step (1)-(4) is to reuse the same virtual test scene. According to the method, different simulation technologies based on the same test scene are shared in the project development process of asingle ECU of the intelligent vehicle, so that the function and performance of the controller are well verified, and the safety and reliability of the vehicle in the actual driving process are ensured.

The invention relates to a method for calculating the loss of an MMC (Modular Multilevel Converter). The method comprises the following steps: (1) extracting a parameter; (2) interpolating the parameter to generate a figure and a table of conduction losses and switching losses; (3) simulating to obtain current and input environment temperature, and looking up the loss of a current time in the table; (4) calculating a junction temperature, and calculating a next node; (5) converging to obtain loss. By adopting the method, the calculation and simulation time can be shortened greatly, and a more real and reliable data source is provided in comparison to simple curve fitting. By adopting the method, real-time calculation of the internal junction temperature of an IGBT (Insulated Gate Bipolar Translator) module becomes possible; the method has high practical values in state monitoring of the IGBT module, estimation of the service life of the IGBT module, prolonging of the service life of an IGBT module device, and improvement on the reliability of the IGBT module device, and the like.

The invention relates to the simulation technology field, and discloses an FPGA-based power electronic simulation system and method. The FPGA-based power electronic simulation method is applied to a power electronic system. The FPGA-based power electronic simulation method comprises the following steps: downloading a circuit model of a power electronic system in an FPGA module; connecting voltage and current equations of modes in the circuit model and obtaining an admittance matrix of the power electronic system, wherein the dimensions of the admittance matrix will not change along with changes of the switch state of a circuit in the power electronic system; updating corresponding parameters of switches that change in state in the admittance matrix if the switch state of the circuit in the power electronic system changes; and resolving state parameters of the circuit model of the power electronic system according to the updated admittance matrix, and simulating the power electronic system. In this way, an admittance matrix of a system is prevented from being re-calculated every time when the state of a switch changes. The simulation time is saved, and the simulation efficiency is improved.

The present invention provides a hard / soft cooperative verifying simulator based on a SystemC simulator, capable of reducing overhead of context switching control thereby to shorten processing time. Time keepers for controlling simulation times of a plurality of threads are provided corresponding to the threads generated as simulation models for hardware and software. Each of the time keepers has a variable which holds a simulation time for each thread, a variable which holds a summation time, and a break request queue which stores a break time and its corresponding break method therein. The time keeper manages both variables and the queue in response to six types of method invocations from the thread, and invokes a wait function of the SystemC simulator when necessary. It is thus possible to reduce the number of times that a wait function invocation is performed, and shorten the entire processing time.

A method of simulating transmission of data from a transmitter to a receiver in a radio communications network, the method including calculating an average amount of data to be transmitted to the receiver in a considered transmission time interval based on a relationship between an interferential condition assumed to be experienced at the receiver and a data transmission throughput, the relationship being determined by a link-level simulation of the link between the transmitter and the receiver.

The invention discloses a method for fault simulation of a direct current transmission system. The method comprises the steps that 1, whether a direct current system is in the same electrical island with the position where a short-circuit fault occurs or not is judged according to the position where the short-circuit fault occurs, and if not, no operation is conducted by a direct current system; 2, if the direct current system and the fault position are in the same electrical island, whether the fault lasting time is shorter than the operation time of a 100Hz harmonic wave, a zero sequence current and communication failure protection of the direct current system or not is judged, if yes, the step 5 is conducted, and if not, the step 3 is conducted; 3, short-circuit voltage calculation is conducted on an alternative current bus in the island; 4, whether protection is started or not is judged according to the short-circuit fault type; 5, according to fault information, whether a direct current circuit stable control strategy needs to be started or not is judged. If yes, operation of power set adjustment is conducted according to a strategy table and if not, exiting is conducted. According to the method, modeling and transient state simulation which are conducted by simulation software on the direct current system are avoided and when simulation of the fault of an AC / DC system is guaranteed, enough accuracy of response of the direct current transmission system is achieved.

The invention belongs to the electromagnetic transient analysis field in an electric power system, and particularly relates to a modeling method for a broadband equivalent model for performing analysis on a tower interlamination transient voltage of an ultra-high-voltage direct current converter valve. The modeling method specifically comprises the steps of taking a valve layer as a unit, and establishing a key component lumped parameter equivalent model in the valve layer and a valve layer terminal capacitor model; enabling the key component lumped parameter equivalent model in the valve layer and the valve layer terminal capacitor model to be connected according to an actual electrical connection condition of the valve tower to obtain the final the broadband equivalent model for performing transient voltage analysis on the tower interlamination of the ultra-high-voltage direct current converter valve. By considering the influence on the valve interlamination voltage distribution from the key component parameters in the valve and shielding cover stray capacitance parameters under a voltage effect, the integrated broadband equivalent circuit model is applicable to perform accurate and efficient analysis on the tower interlamination transient voltage of the ultra-high-voltage direct current converter valve under various kinds of voltages.

The present invention provides an architecture code 20 including object circuit information 23 for mapping an object circuit that is at least part of a circuit for executing an application onto part of a logic circuit where circuits can be dynamically reconfigured, interface circuit information 24 for mapping an interface circuit in contact with the object circuit onto the logic circuit, and boundary condition 26 to be realized in the interface circuit. A data processing system in the present invention includes a load unit obtaining an architecture code 20, a mapping unit for mapping the object circuit and the interface circuit in contact with the object circuit onto the logic circuit region according to the object circuit information 23 and the interface circuit information 24 of the architecture code, and a behavior control unit for controlling the interface circuit according to the boundary condition 26 of the architecture code.

The invention discloses an automobile analogue communication protocol analyzer. The automobile analogue communication protocol analyzer comprises an analyzing end, a diagnosing end and a diagnosis protocol interface; the diagnosing end is used for performing comparative judgment on the frame sequence frame of a request diagnosis protocol sent by the analyzing end and the format of the protocol data source read by the diagnosis protocol interface; the diagnosing end returns diagnosis testing data to the analyzing end for protocol analysis and visual display; and the analyzing end packs the data generated after the analysis and sends the protocol frame sequence data to the diagnosing end. An analyzing method of the automobile analogue communication protocol analyzer is disclosed. The analyzing method comprises the steps that the analyzing end sends a diagnosis protocol to the diagnosing end and judges whether the analyzing end needs a protocol analysis request; the diagnosing end adds a protocol identifiers to different function modules of the analyzing end, and the diagnosing end reads special function identifiers of different function modules and modifies the identifiers based on prompt messages of different function modules. The automobile analyzer can collect the automobile fault information and generate a reply command rapidly, and the pseudotime is shortened greatly.

The invention discloses a dynamic equivalence method for large-scale photovoltaic power station grid connection, and belongs to the technical field of electric system control. The method comprises the steps of firstly, calculating the equivalent and uniform input illumination intensity of each grid-connected photovoltaic power generation unit under the non-uniform illumination condition, then, grouping the grid-connected photovoltaic power generation units according to the equivalent and uniform input illumination intensity, aggregating the grid-connected photovoltaic power generation units in the same group into one grid-connected power generation equivalence unit, and finally calculating the equivalent input illumination intensity of each equivalence unit. According to the dynamic equivalence method for large-scale photovoltaic power station grid connection, the dynamic equivalence problem of the large-scale photovoltaic power station grid connection is solved, the number of orders of a model is remarkably reduced, the simulation time is shortened, and meanwhile the influence of a photovoltaic power station on a system can be correctly reflected.

The invention relates to a steel ingot solid phase movement simulation technology, in particular to a method for simulating solid phase movement in a steel ingot, which is used in the casting process of carbon steel and alloy steel ingot under vacuum and non-vacuum conditions. The method comprises the following steps: determining the solid phase movement critical speed and movement termination critical solid phase fraction of alloy; calculating mass, momentum, energy and component conservation equations and calculating a solid phase fraction field; determining an initiating position for forming a sedimentarypile on the gravity direction; taking the initiating position as a boundary to divide the steel ingot into an upper part and a lower part; reducing solid phase fraction and solid phase components, increasing liquid phase components for a grid cell in which the liquid flow rate is less than the solid phase movement critical speed and the solid phase fraction is larger than zero but smaller than the movement termination critical solid phase fraction along the gravity direction at the upper part of the steel ingot, and performing temperature transfer with a bottom cell; and increasing solid phase fraction and solid phase components, reducing liquid phase components for a grid cell in which the solid phase fraction is smaller than the movement termination critical solid phase fraction at the lower part of the steel ingot, and performing temperature transfer with a top cell.

The invention discloses a method for dynamically reconfiguring a simulation environment, comprising the steps of: (1) newly creating one or a plurality of binary files including configuration files and simulation state record files, and establishing a connection with a simulation model; (2) establishing a one-to-one corresponding relationship between the data of the configuration files and the configuration parameters of the simulation model, and finishing an initialization setting for the configuration files and the simulation model; (3) starting a simulation excitation by the simulation model, recording each state in the simulation process in the simulation state record files, and adjusting the parameter setting of the configuration files according to the simulation state change; (4) reading the configuration files regularly by the simulation model in the simulation process and determining whether the configuration files have a data change, if so, then updating the configuration parameters by using the data read from the configuration files and adjusting the simulation system; or else, then continuing to operate the simulation; and (5) repeating the steps (3) and (4) until a simulation purpose is achieved, and then concluding the simulation process. According to the method, the simulation time is greatly reduced and the simulation is prevented from being failed.

The invention discloses a method for quickly obtaining a node simulation state in a digital gate level circuit, and mainly solves the problems of high difficulty and long time consumption on the aspect of gate level netlist simulation verification in the prior art. The method comprises the following steps that: 1) according to a given gate level circuit, obtaining a connection relationship between the external input and the external output of the gate level circuit and an internal node; 2) describing the logic relationship of the gate level circuit with a hardware language to generate a gate level circuit logic description file; 3) according to the connection relationship in 1), converting the gate level circuit into an RTL (Register-Transfer Level) description unit; 4) according to the connection relationship of the gate level circuit, generating a simulation test file with a software language; and 5) adding the files generated from S2) to S4) into commercial simulation software to be simulated to obtain the simulation state of the internal node of the gate level circuit. By use of the method, simulation complexity and time can be greatly reduced, gate level netlist simulation verification is improved, and the method can be used for extracting gate level netlist key nodes and accelerating the gate level netlist simulation verification.

The invention provides an ADPSS-based distributed power flow controller modeling and simulation method. Electromagnetic transient simulation of a distributed power flow controller on a power system digital simulation system ADPSS platform can be realized. The method comprises the steps that a double-loop power transmission system simulation model is established under the ADPSS / ETSDAC simulation environment, a DPFC device is appropriately simplified by using the UDM function module of the ADPSS / ETSDAC, a series side current converter equivalent mathematical model is established by using an equivalent voltage source, and a parallel side current converter equivalent mathematical model is established by using an MMC mean value model. The dynamic and static characteristics of the DPFC device and the regulation and control function for the system power flow can be reflected under the premise of guaranteeing the simulation scale so that the simulation accuracy can be guaranteed and the simulation time can be shortened; and the more reliable, more comprehensive and more detailed theoretical support can be provided for actual power grid safe and stable operation of the DPFC device, and the foundation can be laid for popularization and application of the distributed power flow controller.