CN102508985A - Circuit simulation optimizing method based on multi-field unified modeling language - Google Patents

Abstract

The present invention relates to a kind of circuit simulation optimization method based on multi-field unified modeling language, and its steps are as follows: (1) draw the circuit diagram that needs to be simulated; (2) convert the circuit diagram into a standard mo file for Modelica simulation; (3) adopt The DC analysis method converts the standard mo file used for simulation into a DC analysis mo file; (4) uses the small data and short step method to simulate the DC analysis mo file, and then obtains the initial value data table of each device; (5) in the step Select the DC initial value of each device in the initial data table of each device obtained in (4), and each device gets the last value as the DC initial value; (6) restore the standard mo file in the step (2), which will be performed by the step ( 5) The obtained DC initial value of the device is loaded into the simulation file as the initial value of the device, and the short-time and large data volume simulation with the initial value of the device is re-conducted, and the final result is obtained. The invention can improve the speed of the simulation system and can be widely used in the field of circuit simulation optimization.

Description

A circuit simulation optimization method based on multi-domain unified modeling language

technical field

The invention relates to a circuit simulation optimization method, in particular to a circuit simulation optimization method based on a multi-field unified modeling language.

Background technique

Unified Modeling Language has a domain-independent general model description capability. Because of the unified model description form, the method based on Unified Modeling Language can realize the seamless integration between different domain subsystem models of complex systems. In 1996, EUROSIM, the European simulation association, organized 14 experts in the field of modeling and simulation from 6 countries including Sweden to conduct research on multi-domain physical unified modeling technology, and proposed to research and design the next generation of multi-domain unified modeling through international open cooperation. Language Modelica. Its model library has covered many engineering fields such as vehicle dynamics, system dynamics, fuel cells, thermodynamics, fuzzy control, and circuit simulation. Aiming at the consistency of mathematical logic of experimental components in different disciplines, based on multi-field physics unified modeling theory and constraint representation theory, using Modelica specification, combined with equations, functions, algorithms, charts, structures, if expressions, when expressions and other constraint expressions Elements, as well as various built-in operation functions provided by the Modelica specification, represent the mathematical logic of the virtual experimental components in a consistent manner.

To solve the mathematical model of the virtual experiment, firstly, form a Document Object Model (DOM) tree through lexical, grammatical and semantic analysis. Based on the DOM tree, through aggregation expansion, inheritance expansion, connection expansion and component instantiation, a hierarchical The mapping of the virtual experimental model of the structure to the flat mathematical model; for the differential algebraic subsystem in the model, an index reduction method based on structural analysis is proposed to realize the index reduction processing of the high-index DAE system; the discrete events in the model are transformed into Numerical traversal function, through the zero-crossing detection of the traversal function to judge the triggering of the event, combined with the existing numerical solution algorithms for DAE, such as DASSL, Sundals, etc., ODE, linear/nonlinear algebraic system, through event iteration and re The initialization process realizes the numerical solution of the continuous-discrete mixed virtual experimental model, and completes the formatted output of the result data. With the development of information technology, as an effective supplement to traditional experimental teaching, virtual experimental teaching has become an important means to strengthen practical teaching and improve teaching quality. It can not only replace traditional experimental teaching to a certain extent, but also overcome Various constraints and drawbacks of traditional experiments can effectively solve many problems in the current experimental teaching, and achieve the purpose of optimizing educational resources and improving teaching quality. Virtual experiment is a new type of experimental teaching system established under the guidance of modern educational theory and based on computer simulation technology, multimedia technology and network technology.

In the virtual experiment system using Modelica language as a unified modeling language, the OPENMODELICA platform is used as a simulation tool (its simulation kernel is Modelica language). An important content is to carry out circuit simulation. Since the multi-domain unified modeling language Modelica only has a transient simulation language and lacks a DC analysis language, when using this language to simulate a circuit containing an energy storage element (such as a capacitor), its element Each initial value of the device starts from 0. Therefore, the output DC stabilization time for some specific circuit simulation data is too long, which seriously affects the usability. As shown in Figure 1 and Figure 2, when the existing simulation circuit is in use, the stable simulation time required is greater than or equal to 10 seconds (set value), and the actual test is 56.4 seconds, which is a long simulation time.

Contents of the invention

In view of the above problems, the object of the present invention is to provide a circuit simulation optimization method based on a multi-domain unified modeling language that can effectively reduce the simulation time and improve the speed and availability of the entire simulation system without affecting the accuracy of the simulation.

To achieve the above object, the present invention takes the following technical solutions: a circuit simulation optimization method based on multi-domain unified modeling language, which comprises the steps of: (1) drawing circuit diagrams that need to be simulated; (2) converting circuit diagrams into Modelica simulations The standard mo file used is a disk file format recognized by the Modelica kernel; (3) The standard mo file used for simulation is converted into a DC analysis mo file by the DC analysis method; (4) Small data and short steps are used The method simulates the DC analysis mo file, and then obtains the initial value data table of each device; (5) selects the DC initial value of each device from the initial data table of each device obtained in step (4), and takes the last value of each device A value is used as the DC initial value; (6) restore the standard mo file in the step (2), and load the device DC initial value obtained by the step (5) into the simulation file of the step (2) as the initial value of the device, Rerun short, high-data-volume simulations with device initial values and get final results.

In the step (4), in the small data and short step method, the small data is less than 100 data, and the short step is less than 0.01s.

The present invention has the following advantages due to the adoption of the above technical scheme: the present invention converts the standard mo file into a direct current analysis mo file by adopting the direct current analysis method, and adopts a small data short step method to simulate the direct current analysis mo file, and calculates and generates various In the device initial value data table, select the last value as the DC initial value, and use this DC initial value as the initial value of the next simulation device, thus greatly reducing the simulation time and improving the speed of the entire simulation system. The invention can be widely used in the field of circuit simulation optimization.

Description of drawings

FIG. 1 is a schematic diagram of a simulation circuit based on the multi-domain unified modeling language Modelica in the prior art;

Fig. 2 is a schematic diagram of the data stabilization effect when the simulation reaches 10 seconds in Fig. 1;

Fig. 3 is a schematic flow sheet of the present invention;

Fig. 4 is the waveform effect diagram of emulation after optimization of the present invention;

Fig. 5 is a partial expanded view of Fig. 4 .

Detailed ways

The invention utilizes the multi-field unified modeling language Modelica to simulate the circuit, and requires the actual simulation time to be shortened as much as possible in addition to requiring the results to be true and credible. Since the output data DC stabilization time is too long, the set system simulation time cannot be shortened. In the actual simulation, the actual simulation time T _R =K T _S , where T _S is the set system simulation time, and K is the coefficient mainly depends on the speed of the hardware equipment for operation, but the value of K is often greater than 50, that is to say, the design When the system simulation time T _S is 0.1s, the actual simulation time T _R is often greater than 5S, which is the characteristic of all simulation software and cannot be changed. Under the condition that the system hardware remains unchanged, K will not change, so the best way to reduce the actual simulation time T _R is to reduce the design system simulation time T _S . It is also very important to set the sampling number of the simulation data, because the result data of the simulation are all double floating point numbers. Distortion of the output waveform. The present invention will be described in detail below through specific embodiments.

As shown in Figure 3, the present invention uses as little data as possible, such as 100 sampling points, to obtain the initial DC value of the device in the initial small data short-time transient simulation, and in the follow-up simulation with the initial value of the device In , the amount of data will be set according to the length of the simulation time. In order to reduce the simulation time T _S of the design system, it is necessary to complete an effect similar to the DC simulation in the SPICE language. The steps that the present invention optimizes system simulation time T _S are as follows:

1) Draw the circuit diagram that needs to be simulated (as shown in Figure 1);

2) convert the circuit diagram drawn in step 1) into a standard mo file for Modelica simulation, and the mo file is a disk file format recognized by the Modelica kernel;

3) Convert the standard mo file used for simulation into a DC analysis mo file, that is, adopt the general DC analysis method in the prior art, disconnect the bypass capacitor C2 and the coupling capacitors C1 and C3, short-circuit the voltage source Vs, and connect the current source Is Open the circuit and get the DC analysis mo file;

4) Use the method of small data and short step to simulate the DC analysis mo file, and then obtain the initial value data table of each device (as shown in Table 1), where the small data is less than 100 data, and the short step is less than 0.01 s;

Table 1 device initial value data sheet

5) Select the DC initial value of each device from the initial data table of each device obtained in step 4), and each device takes the last value as the DC initial value;

Since each device has a series of results, and the data at the front may be unstable, the present invention takes the last value of each result as the DC initial value of the device;

6) Restore the standard mo file in step 2), load the DC initial value of the device obtained in step 5) into the simulation file in step 2), and use it as the initial value of the device, and perform the second short circuit with the initial value of the device Time, large amount of data simulation, to obtain the final simulation results (as shown in Figure 4, Figure 5), the optimized simulation stabilization time is 0.12 seconds (design system simulation time T _S is 0.12 seconds), the simulation result data is correct, The overall simulation speed of the system is greatly improved. The present invention effectively reduces the system simulation time T _S , for example, the initial voltage of the capacitor C3 is set to 4V, and then the device initial value in the device initial value memory is modified.

In summary, the present invention uses the method of generating DC mo files in step 3), step 4) and step 5) to calculate and generate the DC initial value of each device with small data, and will greatly reduce system simulation in step 6). Time T _S , you can get a stable result.

为4秒，整个仿真结果才稳定可用。本发明利用步骤3)和步骤4)仿真后，在0.01s得到一个初始值，再利用步骤5)将初始值加到步骤6)的器件初始文件中，这样步骤6)就可以设置时长T_S为0.3秒，因此大大减少了仿真时间，提高了整个仿真系统的速度。The simulation in the prior art only needs to perform step 1), step 2) and step 6) to obtain the simulation result, but because the system simulation time TS needs to be set very long in the prior art in step 6), for example, the actual circuit of a certain circuit simulation time

4 seconds, the entire simulation result is stable and usable. The present invention utilizes step 3) and step 4) after simulation, obtains an initial value at 0.01s, then utilizes step 5) to add the initial value to the device initial file of step 6), so that step 6) can set the duration T _S It is 0.3 seconds, so the simulation time is greatly reduced and the speed of the whole simulation system is improved.

Above-mentioned each embodiment is only for illustrating the present invention, and each part structure and the step of the present invention all can be changed to some extent, on the basis of the technical solution of the present invention, all according to the principle of the present invention to the structure of individual part and step Improvements and equivalent transformations should not be excluded from the protection scope of the present invention.

Claims (2)

1. circuit simulation optimization method based on the multidomain uniform modeling language, it comprises the steps:

(1) drafting needs the circuit diagram of emulation;

(2) convert circuit diagram to standard mo file that Modelica emulation is used, the mo file is a kind of disk file form that the Modelica kernel is admitted;

(3) the standard mo file conversion of adopting the dc analysis method that emulation is used becomes dc analysis mo file;

(4) adopt the short step-length method of small data that dc analysis mo file is carried out emulation, and then obtain the initial value data table of each device;

(5) select the direct current initial value of each device in each the device primary data table that in step (4), obtains, each device is got last value as the direct current initial value;

(6) the standard mo file in the recovering step (2); To be loaded in the simulation document of said step (2) initial value by the device direct current initial value that step (5) obtain as device; Again have short time, the big data quantity emulation of device initial value, and obtain net result.

2. a kind of circuit simulation optimization method based on the multidomain uniform modeling language as claimed in claim 1 is characterized in that: in the said step (4), in the short step-length method of said small data, adopting small data is less than 100 data, and short step-length is less than 0.01s.

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