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 a discrete-state event-driven simulation method for power electronics hybrid system simulation. Based on the hybrid characteristics of power electronics systems, simulation methods are respectively designed for continuous states and discrete events coexisting in power electronics systems. The simulation The method includes: a flexible adaptive algorithm with variable order and step size, and an event-driven mechanism that automatically triggers simulation calculations by discrete events; the continuous state is described by the state variable method, and discrete events are defined as the trigger source of simulation calculations. The discrete-state event-driven simulation method for power electronic hybrid system simulation disclosed by the invention solves the problems of large amount of calculation and time-consuming simulation of complex power electronic systems under the premise of ensuring accuracy.

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 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 provides a distribution network reliability evaluation method considering load characteristics and distributed power access, which fully considers different user types and time-series load characteristics in different seasons, so that the evaluation results are more in line with the actual operating conditions of the power grid; At the same time, the island support effect of distributed power access on the distribution network is also considered, so that the scope of application of this evaluation method is wider and it can cope with more diverse power distribution scenarios. The existing distribution network reliability evaluation usually does not consider the timing change of the load, and the peak load is used for simulation, which will inevitably amplify the impact of the fault. However, the present invention considers load characteristics such as load timing characteristics and user types in the reliability evaluation. It can improve the prediction results of the reliability index of the load point and the system, and be closer to the actual value.

The invention discloses a large-scale power distribution network integral model simplification method applicable to electromagnetic transient simulation. The large-scale power distribution network integral model simplification method comprises the following steps of: dividing a large-scale intelligent power distribution system into two parts, i.e., an external system and a research system; connecting the external system and the research system through a plurality of branches; establishing electromagnetic transient simulation models of the external system and the research system respectively; setting a low-dimension system model order q (q is less than n) according to a simulation actual demand and computing resource, wherein n represents order of the original external system model; selecting a base calculation method corresponding to the number of columns of a matrix B input in an external system state equation; performing re-orthogonalization processing on a base V by using a re-orthogonalization method; calculating that A' is equal to VTAV, B' is equal to VTB, C' is equal to CV and D' is equal to D to obtain a low-dimension simplified system model; and performing simulation computation in linkage with a detailed model of the research system in place of the original external system model to obtain a detailed transient process in the research system. According to the large-scale power distribution network integral model simplification method, the simulation calculation efficiency is increased, large-scale system analysis simulation is oriented, and inevitable choice of operation requirements under various on-line application scenes is met.

The invention relates to the technical field of electric power, and discloses a generator PSS model checking system. The system comprises a power network data input module, a checking data generationmodule, an execution calculation module and a checking result processing module. One end of the grid data input module is connected with the grid, the other end of the grid data input module is electrically connected with one end of the verification data generation module, the other end of the verification data generation module is electrically connected with one end of the execution calculation module, and the other end of the execution calculation module is electrically connected with one end of the verification result processing module. The single-machine infinite-bus test system constructed on the basis of the checking data generation module carries out simulation comparison on the designated generator with and without PSS, the simulation calculation amount is small, and the influenceof the designated generator with and without PSS on the step response of the excitation reference voltage can be obviously reflected in the single-machine system.

The invention discloses an equivalent simulation method based on a full-bridge sub-module MMC considering multiple locking modes, comprising: obtaining the bridge arm current of the corresponding bridge arm and the switch signal of each full-bridge sub-module IGBT of the bridge arm; The equivalent circuit of the full-bridge sub-module is constructed according to the parameters; the corresponding simulation system is established according to the equivalent circuit of the full-bridge sub-module, and the simulation is carried out. The MMC equivalent simulation method of the present invention uses the internal mechanism of numerical calculation and electromagnetic simulation to equivalent the sub-modules to the Thevenin equivalent branch, avoiding frequent disconnection of a large number of power electronic devices, and greatly reducing the simulation calculation time; at the same time, it introduces real The diode device considers various blocking modes of the full-bridge sub-module, and can accurately simulate each blocking state of the full-bridge sub-module under the premise of ensuring the simulation speed.

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 present invention provides a method for correcting the measured values ​​of thermocouples to obtain the temperature of the drilled bone at the actual drilling point, including: 1. Establishing three finite element analysis models; The highest measured temperature value; optimize Model 2 and Model 3, and apply the optimization results to Model 1; 3. Simulate the optimized Model 1, Model 2, and Model 3, and extract the highest simulated temperature value; 4. Calculate in different Under the combination of drill bone parameters, the relative error of the maximum simulated temperature of model 2 and model 3 relative to model 1, and the relative error formula is fitted, and the model is calculated according to the relative error formula and the maximum measured temperature values ​​of model 2 and model 3 1. The highest temperature value of the actual drilling point; 5. According to the highest temperature value of the actual drilling point, select the bone drilling parameters of the bone surgery and control the range. The invention also provides a computer device to improve the accuracy of the highest temperature value of the drilled bone at the actual drilling point.