44results about How to "Reduce the amount of simulation calculation" patented technology

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 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 discloses a discrete state event-driven simulation method for power electronic hybrid system simulation. Based on the hybrid characteristics of a power electronic system, a simulation method is designed for a continuous state and a discrete event coexisting in the power electronic system. The simulation method comprises a flexible adaptive algorithm with variable order and step sizeand an event-driven mechanism which automatically triggers simulation calculation through the discrete event. The continuous state is described by a state variable method. The discrete event is defined as a trigger source of simulation calculation. The discrete state event-driven simulation method for power electronic hybrid system simulation solves the problems of large simulation computation andlong time of a complex power electronic system under the premise of ensuring accuracy.

The present invention relates to a method for determining patient-specific blood vessel information. More specifically, the present invention relates to a method for determining patient-specific cardiovascular information by applying a simplified coronary circulation model thereto. Furthermore, the present invention relates to a method for determining a blood flow rate for branches of a blood vessel having originated from an artery of each patient. According to the present invention, the method for determining cardiovascular information by using a computer system comprises the steps of: receiving image data including a plurality of coronary arteries having originated from the aorta; processing the image data so as to generate a three-dimensional shape model of the plurality of coronary arteries; simulating a blood flow for the generated three-dimensional shape model of the plurality of coronary arteries; and determining a fractional flow reserve (FFR) of the respective coronary arteries with the blood flow simulation result. In the blood flow simulation step for the three-dimensional shape model of the plurality of coronary arteries, a computational fluid dynamics model is applied to the three-dimensional shape model of the coronary arteries, and a centralized parameter model to be combined with the computational fluid dynamics model uses a simplified coronary circulation model including coronary arteries, capillaries of the coronary arteries, and coronary veins.

The invention discloses an equivalent simulation method based on a clamping double sub-module MMC (modular multilevel converter) and considering various locking modes. The method comprises: obtaining a bridge arm current of a corresponding bridge arm and a switch signal of an IGBT of each clamping double sub-module of the bridge arm; according to operational parameters, constructing an equivalent circuit of the bridge; and according to the equivalent circuit of the bridge arm, establishing a corresponding simulation system and performing simulation. According to the equivalent simulation method for the MMC, the sub-modules are equivalent to Thevenin equivalent branches by utilizing internal mechanisms of numerical calculation and electromagnetic simulation, so that frequent switch-on or switch-off of a large amount of power electronic devices is avoided and the simulation calculation time is greatly shortened; and at the same time, real diode devices are introduced, so that the locking states of the clamping double sub-modules can be accurately simulated on the premise of ensuring the simulation speed.

The invention discloses a fast action sequence and data field algorithm. The fast action sequence and data field algorithm comprises the following steps: step 1, determining combat entities, combat operations and combat missions of adversarial both parties according to a solution deduction plan; step 2, determining an entity model according to the combat entities of the adversarial both parties to determine an attribute parameter, reading a direction graph attribute or a performance attribute according to the plan requirements for antenna parameter configuration and performing enemy state identification; step 3, establishing a series of interrelated and hierarchical action sequences according to the combat missions and analyzing an adversarial relationship; step 4, comprehensively judging whether the simulation is completed or not, ending if yes and returning to the step 3 by advancing a time event sequence if not. According to the fast action sequence and data field algorithm, disclosed by the invention, based on adversarial clustering data mining, a simulation event time sequence can be established, so that the simulation calculation amount among adversarial units can be effectively reduced; meanwhile, fast data field drawing can be performed on electromagnetic situations, so that the simulation efficiency and the visualization effect are improved.

The invention relates to a high-voltage motor stator coil corona-preventing structure optimizing method based on electric field analysis. The high-voltage motor stator coil corona-preventing structure optimizing method includes the following steps: determining the stator coil corona-preventing structure analysis modeling portion; obtaining modeling parameters according to the structure and the size of the modeling portion determined in the step (1); building a three-dimensional finite element model of the coil corona-preventing portion according to the modeling parameters obtained in the step (2); defining the characteristics of various materials of a coil and the insulation corona-preventing portion in the calculating model; determining the type of stimulation exerted on the stator coil calculating model and boundary conditions; carrying out finite element calculation and the electric field analysis on the coil calculating model, and judging the problems of the corona-preventing structural design. According to the high-voltage motor stator coil corona-preventing structure optimizing method based on the electric field analysis, the three-dimensional finite element analysis model is built by reasonably simplifying and assuming a practical model, and the visible and accurate corona-preventing layer electric field distribution result is accordingly obtained; in addition, the simulation calculated amount can be effectively reduced, and the simulation efficiency can be improved.

The invention discloses a construction method of a rail train collision simulation simplified model. The construction method comprises the following steps: carrying out response surface division on atarget intermediate train; performing a collision simulation experiment to obtain response displacement and response force of each response surface at a preset collision speed; identifying each interval section as a plastic deformation interval section or an elastic deformation interval section based on the deformation amount of each interval section, and calculating the rigidity of each elastic deformation interval section, the deformation amount being related to the response displacement of the response surface, and the rigidity being related to the response displacement and the response force of the response surface; and then constructing a rail train collision simulation full model, and replacing the elastic deformation interval sections of all intermediate trains on the rail train collision simulation full model by mass points and discrete beam units based on the calculated rigidity. By means of the method, more reasonable and accurate simplification is achieved.

The invention relates to a voltage safety evaluation method and a voltage safety evaluation system of a power system. The voltage safety evaluation method comprises the steps that a plurality of preset operation ways satisfying preset operation conditions are acquired, and a state variable set corresponding to every preset operation way is generated; safety performance of transient voltage corresponding to every preset operation way is evaluated according to a preset fault set; linear fitting of state variable sets of a plurality of target operation ways is carried out to acquire a fitting weight coefficient corresponding to every target operation way; according to the fitting weighting coefficients corresponding to the plurality of target operation ways and the transient voltage safety performance, the transient voltage safety index of the power system in a current operation way is calculated. The voltage safety evaluation method and the voltage safety evaluation system of the power system are advantageous in that the voltage safety index of the current operation way is evaluated in a real-time manner; real-time performance is good, and a simulation calculation amount is small; and real-time on-line safety evaluation is realized, and calculation resources are saved.

The invention discloses an acoustic target intensity simulation method based on multi-GPU multi-resolution bounce rays, and mainly solves the problems that the time for carrying out sound ray tube bundle splitting calculation on a CPU in a serial mode is long, and real-time forecasting is not facilitated in the prior art. The method comprises the following steps: 1) drawing a simulation model andcarrying out mesh generation; 2) constructing a KD tree for the subdivided model and generating a virtual aperture surface and an angular top ray of a sound ray tube bundle; 3) tracking the angle toprays, if the four angle top rays of the sound ray tube bundle do not intersect with the same triangular surface element, splitting the sound ray tube bundle in parallel until the splitting frequency reaches a set threshold value, and then performing scattering sound field integration; 4) accumulating scattered sound field integral results of each time, and calculating the sound target intensity. The method reduces the simulation calculation amount, improves the sound target intensity simulation speed, can meet the actual engineering requirements, and can be used for the real-time simulation ofthe sound target intensity on a multi-GPU platform.

The invention belongs to the field of collaborative manufacturing and intelligent manufacturing, particularly relates to a non-ferrous metal smelting production, supply and marketing integrated optimization system, method and device, and aims to solve the problems of low non-ferrous metal smelting production and marketing decision-making efficiency and poor accuracy. The system comprises a model construction module configured to construct a unit model corresponding to historical operation data of a non-ferrous smelting enterprise by adopting a data driving method; a data simulation module configured to logically connect the unit models according to a smelting process and perform simulation through a DEVS discrete event model to generate simulation data; an agent model generation module configured to merge historical operation data and simulation data and construct an agent model of constraint conditions of a cost objective function and a decision variable; a decision optimization module configured to optimize the agent model through an evolutionary algorithm; and an optimal decision output module configured to generate an optimal decision. According to the invention, the productionand marketing decision efficiency and accuracy of non-ferrous metal smelting are improved.

The invention discloses a static superscale DSP cycle simulation method. A static superscale DSP cycle simulation system including an instruction preparation module and an instruction execution module is constructed; the instruction preparation module sets an initial value, acquires an instruction, determines the number of deferred cycles, determines the number of pause cycles and simulates clock propulsion; the instruction simulation module executes function simulation; a mathematical model of a superscale DSP cycle state is constructed from the view of time sequence; by time sequence simulation, an accurate state in a cycle when a DSP assembly line is paused; time sequence calculation mainly includes seeking of a maximum or minimum value and intersection operation which can be efficiently realized by bitwise operation; therefore, copying expense on a large number of register transfer levels and search expense on a register dependency sheet are avoided; the simulation calculation amount is relatively low, and the problems that a superscale DSP simulation method is inaccurate and relatively low in speed during DSP real-time software simulation test at the present are solved.

The invention relates to a novel parasitic switch model. On the basis of a variable-resistance switch model, a switch and an electrical element connected with the switch are combined to form the novel parasitic switch model. The novel parasitic switch model replaces the switch and the electrical element connected with the switch to be substituted into a simulation system admittance matrix as a whole. The electrical element is a resistive element or an inductive element or a capacitive element or a circuit. According to the novel parasitic switch model, due to the fact that the switch is combined with the related element, the switch does not need to be considered separately during simulation, and the number of dimensions of the system admittance matrix is effectively reduced; moreover, when the switch conducts the pulling-closing action, it is only required that the element value at the corresponding position in the admittance matrix is corrected, an admittance matrix does not need to be formed again, therefore, the simulation calculation amount is reduced and the simulation speed and the simulation efficiency are improved. In addition, according to related calculation, the switch model also has higher simulation precision.