379results about How to "Improve simulation speed" patented technology

The invention discloses a double-turntable five-axis numerical control machine tool virtual assembling and numerical control machining simulation method and provides a simulation method capable of improving simulation efficiency under the premise of guaranteeing simulation correctness. The method includes: modeling; conducting three-dimensional modeling of blanks and clamps required in all moving components, a machine tool body and numerical control machining; connecting all moving components and the machine tool body to conduct virtual assembling according to a moving relation by using a Pro/E three-dimensional platform; operating a virtual simulating machine tool; outputting models of all components in a standard template library (STL) form on the basis of the same coordinate system; establishing a double-turntable five-axis numerical control machine tool virtual model; establishing a model tree in VERICUT, and the sequence of model components includes two branches: machine tool body Base - Y axis - X axis - A axis - C axis - clamp - blank and machine tool body Base - Z axis - main axis - tool; the STL assembly model output by Pro/E is led into corresponding components in VERICUT directly, namely the double-turntable five-axis numerical control machine tool virtual model is established; and numerical control machining simulation is operated.

The invention relates to a synthetic aperture radar echo rapid simulation method based on sub-aperture and equivalent scatterer, comprising the following steps: 1) pulses corresponding to all track points are divided into a plurality of pulse groups with equal length along the radar flying direction; 2) a scene is divided into a plurality of small rectangular scenes with the same size, and equidistance rings are divided according to the distance between a radar platform and the target scene; 3) in every equidistance annular region of the small rectangular scene, the backscattering coefficient of the equivalent scatterer is calculated, and a pulse response function of the system is obtained; 4) the range direction processing is carried out, and an echo signal of the central pulse of the pulse groups is obtained by the convolution of an emission signal and the pulse response function; 5) azimuth direction processing is carried out, and echo signals of any other pulses in the pulse groups are calculated by the echo signal of the central impulse in the impulse groups. The method of the invention has the advantages of rapid speed and high precision of the frequency domain processing method, introduces the expansion approximate processing of the azimuth direction and effectively improves the simulation velocity.

A method for reducing the size of post-layout circuit simulation output waveform database without a loss of essential information and accuracy. The reduced waveform database requires significantly less storage than the typical waveform database for post-layout simulation, thereby improving the time required for a waveform tool to access, and for a user to navigate, the post-layout simulation results. The method therefore greatly improves designer productivity during circuit verification and debugging phases. The method can be carried out in a preprocessor to a circuit simulator, in a post-processor to a circuit simulator, or may be directly built into a circuit simulator. The method is applicable to any post-layout netlists with schematic node names or circuit element names.

The invention discloses a simulation method of an MMC (modular multilevel converter). The simulation method comprises the following steps: (1) obtaining operation parameters of an SM (Submodule); (2) construction an equivalent circuit of SM; (3) establishing an artificial circuit of SM; and (4) establishing a simulation system of MMC and simulating the system. According to the simulation method provided by the invention, by the utilization of numerical calculation and electromagnetic simulation internal mechanism, the SM in the MMC can be equivalent to a simple branch formed by a controlled voltage source and an adjustable resistor effectively, and the number of nodes of the system and the corresponding simulation calculation can be greatly reduced, so that on the premise that the simulation precision is ensured, the simulation speed of the MMC is greatly promoted, and the method is applied for MMC design.

The invention discloses a method for improving a transient stability analysis efficiency of an electric power system and relates to the field of the electric power system. The method comprises the following steps of: initializing element parameters of the electric power system and inputting data of the electric power system; selecting a network topology state, a generator state and a load level of the electric power system, and determining an operation state of the electric power system; carrying out Monte Carlo sampling selection on the operation state of the electric power system to form a fault sampling sequence; utilizing a task distribution method facing to a multiprocessor parallel system and distributing the fault sampling sequence; carrying out transient stability analysis on a fault sample based on an energy function method by each processor; receiving a result returned by a processor by a main processor and storing the result into a database; and when the fault sampling sequence X is finished, calculating the possibility index of the transient stability of the electric power system and outputting the result. The method disclosed by the invention meets the requirements of instantaneity of information of the electric power system and improves the analysis efficiency and the safety of the electric power system.

The invention discloses an MMC (Modular Multilevel Converter) bridge arm equivalent simulation method which is mainly used for solving the defect of a simulation technique during the shutting of an MMC. The method comprises the following steps of 1, obtaining bridge arm operating parameters of the MMC, wherein the bridge arm operating parameters comprise bridge arm current and switch signals S1-S3 of each submodule in a bridge arm; 2, constructing a bridge arm equivalent circuit according to the bridge arm operating parameters, wherein the bridge arm equivalent circuit comprises two equivalent voltage sources, two equivalent resistors, two equivalent diodes and an equivalent thyristor; 3, building an MMC simulation system according to the bridge arm equivalent circuit, and performing simulation on the system. According to the MMC bridge arm equivalent simulation method, the complicated bridge arm circuit in the MMC is effectively equivalent to a simple circuit, the node amount and the corresponding simulation operand of the system are greatly reduced, the simulation speed of the MMC is greatly promoted, and very high simulation precision is realized during the normal operation and the shutting of the MMC.

The invention provides an average value modeling and control method applicable to a VSC-MTDC (Voltage Sourced Converters Multi-terminal Direct Current) system. The method comprises the following steps of 1, building a mathematical model of a VSC based on d and q rotational coordinates, and calculating active power and reactive power of an AC side of a converter by combining a VSC-MTDC power transmission system; 2, building a VSC-MTDC controller by taking the active power and the reactive power of the AC side of the converter as reference values to achieve cooperative control of a plurality of converter stations; and 3, simplifying a control process of the VSC-MTDC, and building a VSC-MTDC average value model. The average value model can be applied to a multi-terminal direct current power transmission system, the simulation speed is greatly increased, the simulation efficiency is improved, and the mathematical calculation amount is reduced.

A system and method perform a two-pass fault simulation on an original design representation including a software-modeled design element and a hardware-modeled design element. Logic simulation generates input stimulus for a port on the boundary of the software-modeled design element and the hardware-modeled design element, where such ports are output ports of the software-modeled design element and input ports of the hardware-modeled design element. The input stimulus is merged with test patterns for the original design representation. A modified design representation is generated by replacing the software-modeled design element with a nonfunctional block. Most or all possible faults in the hardware-modeled design representation are seeded. The modified design representation is fault simulated in a first pass using the merged input stimulus and test patterns. Any unseeded faults from the first pass and other possible faults in the software-modeled design representation are then seeded and the original design representation is fault simulated in a second pass. The fault coverage results of the two passes are aggregated to generate an overall fault coverage for the original design representation.

The invention provides a method and a device for simulating a power electronic system in order to solve the problem of low speed of power electronic system simulation in the prior art. The method comprises the following steps of: calculating variation of a topological structure caused by starting and stopping operation of a simulation system by using a Petri Net matrix model; updating a state equation of a continuous sub system of the simulation system according to information of the variation of the topological structure; and calculating the state equation of the continuous sub system to determine a value of a state variable of the simulation system. By using the technical scheme, the power electronic system simulation can be carried out efficiently.

The invention discloses a designing method of an MMC multi-sub-module user-defined integrated component in the technical field of electric power system operation and control. The method comprises the steps that the equivalent state and the equivalent model of each sub-module are determined, and the equivalent models of the sub-modules are combined into a Thevenin equivalent model; the equivalent state of a sub-module in a locking state is corrected; the fault types of the sub-modules are set, and the equivalent models of the sub-modules are corrected according to the fault types of the sub-modules; and compiling of the sub-modules is achieved in electromagnetic transient simulation software PSCAD is achieved. The shortcomings that according to an existing sub-module equivalent model, workload is large when a large-scale MMC system is established are overcome, equivalence of the sub-module locking states is achieved, and the problem that an existing equivalent model cannot set a failure is solved.

The invention discloses a road network dynamic traffic flow prediction method based on Simulink simulation. The method comprises the following steps that 10, basic traffic information of a to-be-predicted road network is acquired, wherein the basic traffic information comprises road network topological structure information and road network traffic operation information; 20, a road network traffic simulation system based on Simulink is created according to the acquired basic traffic information of the to-be-predicted road network; 30, dynamic road network traffic flow prediction is conducted according to the created road network traffic simulation system, and predicted traffic information is extracted. According to the prediction method, the dynamic traffic flow information operating on a large-scale city road network can be precisely predicted in real time.

This invention discloses an emulation technology based on post maintenance and the validity of products in maintenance including: a, structuring a maintenance vector or a sequence, b, structuring a fault frequency sequence, c, structuring a repairing sequence, d, computing the elements of the fault frequency sequence and reparing sequence, e, computing the validity of products and total fault frequency, which makes up some shortcomings of the Markov and Monte-Carlo method and is used in researching the influence of maintenance mode and time to product reliabilities.

The invention relates to a method for carrying out dispatching control on a multi-variety multi-process manufacturing enterprise workshop on the basis of an AC (Automatic Circuit Analyzer) model, which comprises the following steps of: 1, setting a target function of the multi-variety multi-process manufacturing enterprise workshop, and when task information of a task Agent is sent to a decision Agent by a coordination Agent, representing the task information with a directed graph G by the decision Agent and using a dispatching rule which is obtained by the decision Agent through a random algorithm as an initial solution of a tabu search algorithm; 2, by a rule decision element Agent, firstly, calculating a target value F, then searching other dispatching methods from the dispatching field by the tabu search algorithm, and using a solution with the minimum target value as the adopted rule; and 3, carrying out state changing on each cell (i.e. a station) in a cell space according to the dispatching rule awarded by the rule decision element. According to the invention, a complex dispatching system can be described, the practical production is well reflected, the computational efficiency of a model is also considered, and the problem of dispatching the dynamic and complex multi-variety multi-process manufacturing enterprise workshop is rapidly and accurately solved.

The invention relates to modeling methods of MMC (modular multilevel converter) submodules, in particular to an MMC equivalent modeling method with a module latching function. The method is characterized in that an IGBT (insulated gate bipolar transistor) series branch of a submodule is enabled to be equivalent to a resistor series branch, and a capacitor branch is enabled to be equivalent to a resistor and power source series branch. The method includes the following steps: 1, determining equivalent voltage Vsm and equivalent resistance RsmEQ of a module equivalent circuit; 2, determining equivalent circuit parameters. By the method, electromagnetic transient simulation can be performed on a modularized multilevel converter accurately and quickly, and the submodule latching function is provided, so that simulation efficiency is greatly improved and time for simulation is reduced.

The invention relates to the technical field of simulation, and discloses an FPGA-based simulation system and method. The FPGA-based simulation system comprises a model establishing module, a processing module and an FPGA module, wherein the model establishing module is connected with the FPGA module through the processing module; the model establishing module is used for establishing a circuit topology model of a device to be simulated by utilizing a graphical programming method; the processing module is used for mapping the circuit topology model established by the model establishing module to the FPGA module, controlling the FPGA module to calculate according to the circuit topology model and carrying out analog simulation on the device to be simulated; and the FPGA module is furthermore used for compiling the circuit topology model when firstly receiving the circuit topology model of the device to be simulated. In such way, the simulation speed of the device to be simulated can be improved.

The invention discloses a distributed traffic simulation system and a simulation method based on variable region division. According to the invention, a long time segment is divided into a plurality of continuous short time segments; change of distribution of people and vehicle on road network in the short time segments is much smaller than that in the total time segment; and in each short time segment, a region division scheme is adopted according to the distribution rule of people and vehicles, and the change of the number of people and vehicle in the time segments in the region is decreased, therefore, the purpose of balancing the load of each simulation server is achieved.

The invention provides a method for eliminating internal nodes of a metal-oxide-semiconductor field effect transistor (MOSFET) used in rapid circuit simulation. The method comprises the following steps of: making a 4-node MOSFET model which does not comprise any internal node equivalent to a 6-node MOSFET model which comprises internal nodes in a circuit simulation process; solving the voltages of two internal nodes of the MOSFET by an analytic method; calculating the change of an internal node voltage along with an external node voltage; and finally obtaining a transient conductance relation among external nodes of all apparatuses used in matrix calculation. The method has the advantages of ensuring circuit simulation accuracy by considering the effect of MOSFET parasitic resistance on an electrical property, eliminating the internal nodes of the MOSFET, reducing a circuit solving matrix, reducing matrix solving time and increasing circuit simulation speed.

The network simulation service structure includes: the first layer of client layer including client terminals; the second layer of expert knowledge layer including application server and database server and for customizing design process for professional product design with fused expertí»s design experiences and realizing coupling of background simulation tools; the third layer of calculation dispatching layer including dispatching server; and the fourth layer of calculation layer includes N computing servers for completing the computing task of the computing queue. The present invention provides one novel kinds of simulation system structure to provide the users with novel network design service.

The invention discloses a fast simulation method for extreme ultraviolet photoetching thick mask defects. The method is implemented through that a defect multilayer membrane is equivalent to a defect-free plane mirror and a defect panel mirror; firstly, the diffraction spectrum of a mask absorption layer is obtained through thin-mask approximation, and the mask absorption layer subjected to phase compensation is reflected through the defect multilayer membrane; then, an operation of phase compensation is performed again; and finally, through thin-mask approximation and phase compensation, the mask diffraction spectrum of extreme ultraviolet photoetching defects is obtained. According to the invention, the influence of defects on mask imaging can be effectively simulated, and the simulation speed of extreme ultraviolet photoetching thick mask defects can be improved.

The invention discloses a GPU-based RF semi-physical clutter simulation method, which comprises the steps of: constructing a clutter real-time semi-physical simulation platform; subjecting clutter to clutter element division based on a Doppler ring; performing parallel calculation on the divided clutter elements and generating a baseband signal by utilizing a GPU technology; calculating missile and target flight parameters; and conducting multi-system data interchange and transmission, and completing the transmission of a clutter RF signal. The GPU-based RF semi-physical clutter simulation method realizes model parallel calculation on ground division of iso-Doppler rings and equidistance rings in a clutter model through establishing the clutter real-time semi-physical simulation platform and utilizing thread blocks and thread programming in the CUDA, realizes parallel acceleration of the clutter model by utilizing the GPU technology, realizes the data interchange and transmission between the GPU and an RTX real-time operating system, accelerates the simulation speed, and ensures the realistic performance of a homing head electromagnetic environment.