CN107832504B - Method and system for simulating maximum conversion current of multi-terminal direct current system - Google Patents
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Abstract
The invention relates to a method and a system for simulating maximum conversion current of a multi-terminal direct current system. The method comprises the following steps: determining a first calculation model of the conversion current of the multi-terminal direct current system and the resistance value range of each variable resistor according to system conditions; selecting a plurality of resistance values of each variable resistor according to the resistance value range of each variable resistor, and calculating through a first calculation model to obtain a plurality of corresponding conversion current values; determining a maximum value from the multiple conversion current values as an approximate value of the multi-terminal direct current maximum conversion current; obtaining a random calculation error according to a predetermined maximum direct current conversion current accurate value at two ends and a predetermined maximum direct current conversion current approximate value at two ends; and correcting the error of the approximate value of the maximum conversion current of the multi-terminal direct current according to the random calculation error to obtain a maximum conversion current simulation value of the multi-terminal direct current system. By the scheme of the invention, the calculated value of the maximum conversion current suitable for engineering application can be quickly determined.
Description
Technical Field
The invention relates to the technical field of direct current transmission, in particular to a method and a system for simulating maximum conversion current of a multi-terminal direct current system.
Background
In the process of system research and complete set design of a direct current transmission project, the maximum value of conversion current of conversion switches, such as an earth return line conversion switch ERTB and a metal return line conversion switch MRTB, needs to be calculated, so that reference values of corresponding switch parameters are given, and the production of equipment is guided.
The calculation of the conversion current in the traditional multi-terminal direct current transmission project relates to multi-loop direct current impedance, the expression of the conversion current is complex, and the occurrence condition of the maximum conversion current value is difficult to determine. If the maximum accurate value of the conversion current is to be obtained, the maximum accurate value of the conversion current is determined according to the monotonicity of the conversion current expression and the combination of the resistance value range. The process is complex and is not well suited for engineering computing applications.
In summary, the conventional determination process of the maximum conversion current of the multi-terminal dc is complicated, and the calculated value of the maximum conversion current suitable for engineering application cannot be determined quickly.
Disclosure of Invention
Therefore, it is necessary to provide a method and a system for simulating the maximum conversion current of a multi-terminal dc system to solve the problems that the conventional determination process of the maximum conversion current of the multi-terminal dc system is complicated and the calculated value of the maximum conversion current suitable for engineering application cannot be determined quickly.
A method of simulating a maximum converted current of a multi-terminal dc system, comprising:
determining a calculation model of the conversion current of the multi-terminal direct current system and determining the resistance value range of each variable resistor in the calculation model according to system conditions;
selecting a plurality of resistance values of each variable resistor according to the resistance value range of each variable resistor, and calculating through the calculation model to obtain a plurality of corresponding conversion current values;
determining a maximum value from the plurality of conversion current values as an approximate value of the multi-terminal direct current maximum conversion current;
acquiring a two-end direct current maximum conversion current accurate value and a two-end direct current maximum conversion current approximate value of a two-end direct current system which are determined in advance, and obtaining a random calculation error according to the two-end direct current maximum conversion current accurate value and the two-end direct current maximum conversion current approximate value; the two-end direct current maximum conversion current approximate value is calculated through a second calculation model of the conversion current of the two-end direct current system;
and correcting the error of the approximate value of the maximum conversion current of the multi-terminal direct current according to the random calculation error to obtain a maximum conversion current simulation value of the multi-terminal direct current system.
A system for simulating a maximum converted current of a multi-terminal dc system, comprising:
the model determining module is used for determining a calculation model of the conversion current of the multi-terminal direct current system and determining the resistance value range of each variable resistor in the calculation model according to system conditions;
the calculation module is used for selecting a plurality of resistance values of each variable resistor according to the resistance value range of each variable resistor, and calculating to obtain a plurality of corresponding conversion current values through the calculation model respectively;
an approximate value determining module, configured to determine a maximum value from the multiple conversion current values, as an approximate value of the multi-terminal dc maximum conversion current;
the error calculation module is used for acquiring a predetermined two-end direct current maximum conversion current accurate value and a two-end direct current maximum conversion current approximate value of the two-end direct current system, and obtaining a random calculation error according to the two-end direct current maximum conversion current accurate value and the two-end direct current maximum conversion current approximate value; the two-end direct current maximum conversion current approximate value is calculated through a second calculation model of the conversion current of the two-end direct current system;
and the error correction module is used for carrying out error correction on the multi-terminal direct current maximum conversion current approximate value according to the random calculation error to obtain a maximum conversion current simulation value of the multi-terminal direct current system.
A computer-readable storage medium, on which a computer program is stored which, when being executed by a processor, carries out the above-mentioned steps of the method of simulating a maximum converted current of a multi-terminal dc system.
A computer device comprising a memory, a processor and a computer program stored on the memory and executable on the processor, said processor implementing the steps of the above method of simulating maximum converted current of a multi-terminal dc system when executing said program.
According to the technical scheme, the impedance range of each variable resistor of the multi-terminal direct current system is obtained; selecting a plurality of resistance values of each variable resistor in the impedance range of each variable resistor, and calculating through the first calculation model to obtain a plurality of corresponding conversion current values; determining a maximum value from the plurality of conversion current values as an approximate value of the multi-terminal direct current maximum conversion current; obtaining a random calculation error according to the obtained accurate value of the maximum direct current conversion current at the two ends and the obtained approximate value of the maximum direct current conversion current at the two ends; and correcting the error of the approximate value of the maximum conversion current of the multi-terminal direct current according to the random calculation error to obtain a maximum conversion current simulation value of the multi-terminal direct current system. The scheme can effectively avoid the trouble of accurately determining the working condition of the multi-terminal direct current maximum conversion current, has simple process, and can quickly determine the maximum conversion current calculation value suitable for engineering application.
Drawings
FIG. 1 is a schematic flow chart diagram of a method of simulating maximum converted current for a multi-terminal DC system, according to an embodiment;
FIG. 2 is a schematic block diagram of a first computational model of a multi-terminal DC system according to an embodiment;
FIG. 3 is a schematic flow chart diagram of a method of simulating maximum converted current for a multi-terminal DC system in accordance with another embodiment;
FIG. 4 is an equivalent circuit diagram of a two-terminal DC system according to an embodiment;
FIG. 5 is an equivalent circuit diagram of a three-terminal DC system according to an embodiment;
FIG. 6 is a schematic block diagram of a system for simulating maximum converted current of a multi-terminal DC system, according to one embodiment.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.
Although the steps in the present invention are arranged by using reference numbers, the order of the steps is not limited, and the relative order of the steps can be adjusted unless the order of the steps is explicitly stated or other steps are required for the execution of a certain step.
The method can be applied to the technical field of electric power, in particular to conversion current calculation in multi-terminal direct current transmission engineering.
FIG. 1 is a schematic flow chart diagram of a method of simulating maximum converted current for a multi-terminal DC system, according to an embodiment; as shown in fig. 1, the method for simulating the maximum conversion current of the multi-terminal dc system in the present embodiment includes the following steps:
step S101, according to system conditions, determining a first calculation model of the conversion current of the multi-terminal direct current system, and determining the resistance value range of each variable resistor in the first calculation model.
In this step, the system conditions mainly refer to the dc current condition when the system is overloaded and the range of values of the resistances of the respective lines. The first calculation model is established according to an equivalent circuit of the multi-terminal direct current system and an expression of the conversion current and is used for calculating the conversion current of the multi-terminal direct current system. The multi-terminal direct current system refers to a direct current system with three or more terminals, and particularly refers to a three-terminal direct current system. The expression of the conversion current is related to the line resistance, and as the line resistance is affected by line length errors, temperature and the like, the resistance range of each variable resistor on the line can be determined through other earlier researches.
Specifically, a first calculation model for calculating the conversion current of the multi-terminal direct current system is established according to the conditions of the multi-terminal direct current system, such as the direct current condition when the system is overloaded, and the calculation expression and the equivalent circuit of the multi-terminal direct current system, and the resistance value range of each variable resistor in the first calculation model is determined.
And step S102, selecting a plurality of resistance values of each variable resistor according to the resistance value range of each variable resistor, and calculating through the first calculation model to obtain a plurality of corresponding conversion current values.
In this step, the first calculation model has a function of calculating a conversion current, and a plurality of selected resistance values of the variable resistors are input into the first calculation model, and the first calculation model may directly output a corresponding conversion current value. The resistance value range of each variable resistor is determined according to earlier research and actual conditions, and reasonableness is achieved, so that any resistance value combination of each variable resistor is possible.
Specifically, within the resistance range of each variable resistor, selecting a plurality of resistance values of each variable resistor as much as possible, inputting one resistance value of each variable resistor into a first calculation model each time, and obtaining a plurality of corresponding converted current values through calculation of the first calculation model.
And step S103, determining the maximum value from the plurality of conversion current values as the approximate value of the maximum multi-terminal direct current conversion current.
In this step, the plurality of conversion current values are sorted from large to small or from small to large, and the maximum value of the plurality of conversion current values is selected as the approximate value of the maximum multi-terminal direct current conversion current.
Step S104, acquiring a predetermined two-end DC maximum conversion current accurate value and a two-end DC maximum conversion current approximate value of the two-end DC system, and obtaining a random calculation error according to the two-end DC maximum conversion current accurate value and the two-end DC maximum conversion current approximate value; and calculating the two-end direct current maximum conversion current approximate value through a second calculation model of the conversion current of the two-end direct current system.
In this step, the second calculation model of the converted current of the two-terminal dc system is determined according to the conditions of the two-terminal dc system, and the resistance value range of each variable resistor in the second calculation model can also be determined according to the conditions of the two-terminal dc system. The second calculation model is simpler than the first calculation model, and the accurate value of the maximum direct current conversion current at two ends can be directly determined through the second calculation model.
Specifically, according to the resistance value range of each variable resistor in the second calculation model, a plurality of resistance values of each variable resistor are selected, and a plurality of corresponding conversion current values are obtained through calculation of the second calculation model respectively. And determining the maximum value from the plurality of conversion current values as the approximate value of the maximum direct current conversion current at the two ends. And obtaining random calculation errors according to the approximate values of the maximum direct current conversion currents at the two ends and the accurate values of the maximum direct current conversion currents at the two ends directly determined by the second calculation model.
And step S105, carrying out error correction on the multi-terminal direct current maximum conversion current approximate value according to the random calculation error to obtain a maximum conversion current simulation value of the multi-terminal direct current system.
In this step, the error of the three-terminal dc system is approximately corrected by the error of the two-terminal dc system, and specifically, the error correction is performed on the multi-terminal dc maximum conversion current approximate value calculated in the above step S103 according to the random calculation error of the two-terminal dc system, so as to obtain the maximum conversion current simulation value of the multi-terminal dc system.
In the above embodiment, the impedance range of each variable resistor of the multi-terminal direct current system is obtained; selecting a plurality of resistance values of each variable resistor in the impedance range of each variable resistor, and calculating through the first calculation model to obtain a plurality of corresponding conversion current values; determining a maximum value from the plurality of conversion current values as an approximate value of the multi-terminal direct current maximum conversion current; obtaining a random calculation error according to the obtained accurate value of the maximum direct current conversion current at the two ends and the obtained approximate value of the maximum direct current conversion current at the two ends; and correcting the error of the approximate value of the maximum conversion current of the multi-terminal direct current according to the random calculation error to obtain a maximum conversion current simulation value of the multi-terminal direct current system. The method can effectively avoid the trouble of accurately determining the working condition of the multi-terminal direct current maximum conversion current, has simple process, and can quickly determine the maximum conversion current calculation value suitable for engineering application.
Fig. 2 is a schematic structural diagram of a first calculation model of a multi-terminal dc system according to an embodiment.
In an embodiment, as shown in fig. 2, in the step S101, the first calculation model of the converted current of the multi-terminal dc system includes: a multi-terminal random signal generator 210, a multi-terminal analog-to-digital circuit 220 and a multi-terminal maximum value acquisition module 230; each resistance signal output end of the multi-terminal random signal generator 210 is correspondingly connected to a resistance signal input end of each variable resistor in the multi-terminal analog-to-digital circuit 220, and a converted current target signal output end of the multi-terminal analog-to-digital circuit 220 is connected to an input end of the multi-terminal maximum value obtaining module 230.
The multi-terminal random signal generator 210 randomly outputs a plurality of resistance values of each variable resistor according to the resistance value range of each variable resistor in the second calculation model. For example, the multi-terminal random signal generator 210 has 3 resistance signal output terminals, which are a resistance signal output terminal a, a resistance signal output terminal B and a resistance signal output terminal C, respectively, and are correspondingly connected to the resistance signal input terminal a1, the resistance signal input terminal B1 and the resistance signal input terminal C1 of the multi-terminal analog-to-digital converter 220. The multi-terminal simulation circuit 220 is built according to an equivalent circuit diagram of a multi-terminal dc system, and a plurality of resistance values of each variable resistor selected at random are input to the multi-terminal simulation circuit 220, so that a corresponding converted current value can be directly output. The multi-terminal maximum value obtaining module 230 sorts the plurality of conversion current values output from the multi-terminal analog-to-digital converter 220, and outputs a maximum value of the plurality of conversion current values. According to the embodiment, the maximum value of the conversion current values of the multi-terminal direct-current system after random calculation can be conveniently determined through the first calculation model.
In an embodiment, in the step S102, the selecting a plurality of resistance values of each variable resistor according to the resistance value range of each variable resistor, and calculating a plurality of corresponding converted current values through the first calculation model respectively includes: setting the calculation times of the first calculation model, such as 500 times, as preset calculation times; selecting one resistance value of each variable resistor every time in the resistance value range of each variable resistor in the first calculation model, and forming a group of resistance values by one resistance value of each variable resistor; calculating to obtain conversion current values corresponding to the resistance values of all groups through the first calculation model, and accumulating the current calculation times by 1 after each calculation to obtain the corresponding conversion current values; and stopping the calculation if the current calculation times reach the preset calculation times, such as 500 times. Further, the preset calculation times are related to the resistance value range of each variable resistor, the larger the resistance value range of each variable resistor is, the larger the preset calculation times are, when the random resistance value selection times reach a certain order of magnitude, the random calculation error of the random calculation times basically presents a stable level, and the stability of the random calculation error can be maintained to a certain extent. In the embodiment, within the resistance range of each variable resistor, the conversion current values can be obtained as many as possible through multiple calculations of the first calculation model, which is favorable for determining a more accurate approximate value of the maximum multi-terminal direct-current conversion current.
In an embodiment, before the step of stopping the calculation if the current calculation number reaches the preset calculation number, the method includes: if the current calculation times are less than the preset calculation times, jumping to the resistance range of each variable resistor in the first calculation model, reselecting one resistance of each variable resistor, and forming a group of resistances by one resistance of each variable resistor; and calculating to obtain a conversion current value corresponding to the group of resistance values through the first calculation model, and accumulating the current calculation times by 1 after the corresponding conversion current value is obtained through the calculation. Further, the number of groups of combinations of the variable resistors may be estimated approximately, and the number of times of the preset calculation may be set according to the estimated number of groups, so that the number of repeated calculations may be reduced. For example, there are 4 variable resistors in the multi-terminal dc circuit, each variable resistor has 5 resistance values, and the number of the combined groups of the variable resistors is 625, and the preset number of times of calculation can be set to 600. In the embodiment, the calculation times of the first calculation model reach the preset calculation times, so that the multi-terminal direct current maximum conversion current approximate value can be effectively determined.
In an embodiment, in the step S104, before the step of obtaining the predetermined both-end dc maximum converted current accurate value and the both-end dc maximum converted current approximate value of the both-end dc system, the method includes: determining a second calculation model of the conversion current of the two-end direct current system, and determining the resistance value range of each variable resistor in the second calculation model; determining the accurate value of the maximum direct current conversion current at the two ends of the direct current system at the two ends through the second calculation model within the resistance value range of each variable resistor in the second calculation model; selecting a plurality of resistance values of each variable resistor according to the resistance value range of each variable resistor in the second calculation model, and calculating through the second calculation model to obtain a plurality of corresponding conversion current values; and determining the maximum value from the plurality of conversion current values as the approximate value of the maximum direct current conversion current at the two ends.
Wherein the second computational model comprises: the device comprises a two-end random signal generator, a two-end simulation circuit and a two-end maximum value acquisition module; and each resistance signal output end of the random signal generators at the two ends is correspondingly connected with the resistance signal input end of each variable resistor in the simulation analog circuits at the two ends, and the conversion current target signal output end of the simulation analog circuits at the two ends is connected with the input end of the maximum value acquisition module at the two ends. The second calculation model is relatively simple, and the accurate value of the maximum direct current conversion current at two ends can be directly determined through the second calculation model. In the embodiment, a basis is provided for calculating the random calculation error by obtaining the accurate value of the maximum direct current conversion current at the two ends and the approximate value of the maximum direct current conversion current at the two ends of the direct current system at the two ends.
In an embodiment, the selecting a plurality of resistance values of each variable resistor according to the resistance value range of each variable resistor in the second calculation model, and calculating a plurality of corresponding converted current values through the second calculation model respectively includes: setting the calculation times of the second calculation model; selecting one resistance value of each variable resistor every time in the resistance value range of each variable resistor in the second calculation model, and forming a group of resistance values by one resistance value of each variable resistor; calculating to obtain conversion current values corresponding to the resistance values of all groups through the second calculation model; after the corresponding conversion current value is obtained by each calculation, accumulating the current calculation times by 1; and if the current calculation times reach the calculation times, stopping calculation and counting the conversion current values. Further, when the number of times of calculation is more than 1000, the random calculation error tends to be stable. When the number of computations of the first computational model and the number of computations of the second computational model are both sufficiently large, such as 1000, the number of computations of the two computational models may be kept consistent. In the embodiment, within the resistance range of each variable resistor of the second calculation model, the converted current values can be obtained as many as possible through multiple calculations of the second calculation model, which is favorable for determining a relatively accurate approximate value of the maximum converted direct current at two ends.
In an embodiment, in the step S104, the obtaining a random calculation error according to the accurate value of the maximum dc conversion current at the two ends and the approximate value of the maximum dc conversion current at the two ends includes: and calculating the ratio of the accurate value of the maximum direct current conversion current at the two ends to the approximate value of the maximum direct current conversion current at the two ends, and obtaining a first proportional coefficient according to the ratio.
In an embodiment, in the step S104, the obtaining a random calculation error according to the accurate value of the maximum dc conversion current at the two ends and the approximate value of the maximum dc conversion current at the two ends includes: and calculating the ratio of the approximate value of the maximum direct current conversion current at the two ends to the accurate value of the maximum direct current conversion current at the two ends, and obtaining a second proportionality coefficient according to the ratio.
In an embodiment, in the step S105, the performing error correction on the approximated value of the maximum conversion current of the multi-terminal dc system according to the randomly calculated error to obtain the simulated value of the maximum conversion current of the multi-terminal dc system includes: if the random calculation error is a first proportional coefficient, calculating a product of the multi-terminal direct-current maximum conversion current approximate value and the first proportional coefficient, and obtaining a maximum conversion current simulation value of the multi-terminal direct-current system according to the product; and if the random calculation error is a second proportional coefficient, calculating a quotient of the multi-terminal direct current maximum conversion current approximate value and the second proportional coefficient, and obtaining a maximum conversion current simulation value of the multi-terminal direct current system according to the quotient. In the above embodiment, the error correction is performed on the multi-terminal dc maximum conversion current approximate value through the calculated random calculation error, so that the maximum conversion current simulation value of the multi-terminal dc system can be obtained, and the calculated maximum conversion current value suitable for engineering application can be quickly determined.
In a specific embodiment, as shown in fig. 3, the maximum conversion current of the simulated multi-terminal dc system includes:
step S301, acquiring an accurate value of the maximum direct current conversion current at two ends and an approximate value of the maximum direct current conversion current at two ends of the direct current system at two ends.
In an embodiment, as shown in fig. 4, fig. 4 is an equivalent circuit diagram of a two-terminal dc system according to an embodiment. RMRepresenting the resistance (polar line) of the metal circuit, LMRepresenting the inductance (pole line) of the metal loop, RELRepresenting resistance of earth electrode line, REEDenotes the resistance of the ground electrode, LELIndicating the inductance of the earth electrode line, LGRepresenting the inductance of the earth return, CSRepresents a surge capacitance, IdcRepresenting a direct current. The currents converted by MRTB and ERTB are both dc currents, and the calculation of the converted currents only involves the resistors in fig. 4. Therefore, the conversion current expressions of the two-terminal direct current systems MRTB and ERTB are:
the current expression is substantially a direct current IdcThe current flow expression indicates thatMRTBWhen taking the maximum value, RMMaximum, REE、RELMinimum; i isERTBWhen taking the maximum value, REEAnd RELMaximum, RMAnd minimum. Namely, the accurate value of the maximum direct current conversion current at two ends can be directly determined through the current expression. The second calculation model is established according to the equivalent circuit diagram of the two-terminal direct current system shown in fig. 4 and the current expression, and the maximum value of the conversion current value in the multiple random calculations is taken as the approximate maximum conversion current of the two-terminal direct current through the multiple random calculations of the second calculation modelLike values. In the embodiment, a basis is provided for calculating the random calculation error by obtaining the accurate value of the maximum direct current conversion current at the two ends and the approximate value of the maximum direct current conversion current at the two ends of the direct current system at the two ends.
And step S302, obtaining a random calculation error according to the accurate value of the maximum direct current conversion current at the two ends and the approximate value of the maximum direct current conversion current at the two ends.
Specifically, a ratio of the accurate value of the maximum direct current conversion current at the two ends to the approximate value of the maximum direct current conversion current at the two ends is calculated, and the ratio is used as a random calculation error.
Step S303, obtaining an approximate value of the multi-terminal direct current maximum conversion current.
In an embodiment, as shown in fig. 5, fig. 5 is an equivalent circuit diagram of a three-terminal dc system of an embodiment. The subscripts x and d indicate different dc terminals, and comparing fig. 5 and 4, it can be seen that a three terminal dc system has one more dc terminal than a two terminal dc system. Wherein, the first calculation model is established according to the equivalent circuit diagram of the three-terminal direct current system shown in fig. 5. Specifically, the maximum value of the conversion current value in the multiple random calculations is taken as the approximate value of the maximum conversion current of the multi-terminal direct current through the multiple random calculations of the first calculation model.
Step S304, obtaining a maximum conversion current simulation value of the multi-terminal direct current system according to the random calculation error and the multi-terminal direct current maximum conversion current approximate value.
Specifically, a product of the multi-terminal direct-current maximum conversion current approximate value and the random calculation error is calculated, and a maximum conversion current simulation value of the multi-terminal direct-current system is obtained according to the product.
In the embodiment, the accurate value of the maximum direct current conversion current at two ends and the approximate value of the maximum direct current conversion current at two ends of the direct current system at two ends are obtained; obtaining a random calculation error according to the accurate value of the maximum direct conversion current at the two ends and the approximate value of the maximum direct conversion current at the two ends; and obtaining a maximum conversion current approximation value of the multi-terminal direct current system according to the random calculation error and the maximum conversion current approximation value of the multi-terminal direct current. The method can effectively avoid the trouble of accurately determining the working condition of the multi-terminal direct current maximum conversion current, has simple process, and can quickly determine the maximum conversion current calculation value suitable for engineering application.
It should be noted that, for the sake of simplicity, the foregoing method embodiments are described as a series of acts or combinations, but those skilled in the art should understand that the present invention is not limited by the described order of acts, as some steps may be performed in other orders or simultaneously according to the present invention.
Based on the same idea as the method for simulating the maximum conversion current of the multi-terminal dc system in the above embodiment, the present invention further provides a system for simulating the maximum conversion current of the multi-terminal dc system, which can be used to execute the above method for simulating the maximum conversion current of the multi-terminal dc system. For convenience of illustration, the schematic block diagram of the embodiment of the system for simulating the maximum converted current of the multi-terminal dc system only shows the part related to the embodiment of the present invention, and those skilled in the art will understand that the illustrated structure does not constitute a limitation to the system, and may include more or less components than those illustrated, or combine some components, or arrange different components.
Fig. 6 is a schematic block diagram of a system for simulating a maximum conversion current of a multi-terminal dc system according to an embodiment, where the system for simulating a maximum conversion current of a multi-terminal dc system includes:
the model determining module 610 is configured to determine a calculation model of the converted current of the multi-terminal dc system according to system conditions, and determine a resistance range of each variable resistor in the calculation model.
And the calculating module 620 is configured to select a plurality of resistance values of each variable resistor according to the resistance value range of each variable resistor, and calculate a plurality of corresponding converted current values through the calculation model respectively.
An approximate value determining module 630, configured to determine a maximum value from the multiple converted current values as an approximate value of the multi-terminal dc maximum converted current.
The error calculation module 640 is configured to obtain a predetermined maximum direct-current conversion current accurate value at two ends and a predetermined maximum direct-current conversion current approximate value at two ends of the two-end direct-current system, and obtain a random calculation error according to the maximum direct-current conversion current accurate value at two ends and the maximum direct-current conversion current approximate value at two ends; and calculating the two-end direct current maximum conversion current approximate value through a second calculation model of the conversion current of the two-end direct current system.
And an error correction module 650, configured to perform error correction on the multi-terminal dc maximum conversion current approximate value according to the random calculation error, so as to obtain a maximum conversion current simulation value of the multi-terminal dc system.
In one embodiment, for the model determination module 610, the first calculation model of the converted current of the multi-terminal dc system includes: the device comprises a multi-terminal random signal generator, a multi-terminal simulation circuit and a multi-terminal maximum value acquisition module; each resistance signal output end of the multi-end random signal generator is correspondingly connected with the resistance signal input end of each variable resistor in the multi-end analog-to-digital converter, and the conversion current target signal output end of the multi-end analog-to-digital converter is connected with the input end of the multi-end maximum value acquisition module.
In an embodiment, for the calculating module 620, the selecting a plurality of resistance values of each variable resistor according to the resistance value range of each variable resistor, and calculating a plurality of corresponding converted current values through the first calculation model respectively includes: setting the calculation times of the first calculation model as preset calculation times; selecting one resistance value of each variable resistor every time in the resistance value range of each variable resistor in the first calculation model, and forming a group of resistance values by one resistance value of each variable resistor; calculating to obtain conversion current values corresponding to the resistance values of all groups through the first calculation model, and accumulating the current calculation times by 1 after each calculation to obtain the corresponding conversion current values; and if the current calculation times reach the preset calculation times, stopping the calculation.
In an embodiment, for the calculation module 620, it may further be configured to: if the current calculation times are less than the preset calculation times, jumping to the resistance range of each variable resistor in the first calculation model, reselecting one resistance of each variable resistor, and forming a group of resistances by one resistance of each variable resistor; and calculating to obtain a conversion current value corresponding to the group of resistance values through the first calculation model, and accumulating the current calculation times by 1 after the corresponding conversion current value is obtained through the calculation.
In an embodiment, for the approximate value determining module 630, the step of obtaining the predetermined both-end dc maximum converted current accurate value and the both-end dc maximum converted current approximate value of the both-end dc system includes: determining a second calculation model of the conversion current of the two-end direct current system, and determining the resistance value range of each variable resistor in the second calculation model; determining the accurate value of the maximum direct current conversion current at the two ends of the direct current system at the two ends through the second calculation model within the resistance value range of each variable resistor in the second calculation model; selecting a plurality of resistance values of each variable resistor according to the resistance value range of each variable resistor in the second calculation model, and calculating through the second calculation model to obtain a plurality of corresponding conversion current values; and determining the maximum value from the plurality of conversion current values as the approximate value of the maximum direct current conversion current at the two ends.
In an embodiment, for the error calculation module 640, the obtaining a random calculation error according to the two-terminal dc maximum conversion current accurate value and the two-terminal dc maximum conversion current approximate value includes: calculating the ratio of the accurate value of the maximum direct conversion current at the two ends to the approximate value of the maximum direct conversion current at the two ends, and obtaining a first proportional coefficient according to the ratio;
in an embodiment, the error calculation module 640 is further configured to: and calculating the ratio of the approximate value of the maximum direct current conversion current at the two ends to the accurate value of the maximum direct current conversion current at the two ends, and obtaining a second proportionality coefficient according to the ratio.
In an embodiment, for the error correction module 650, the performing error correction on the approximated value of the maximum conversion current of the multi-terminal dc system according to the randomly calculated error to obtain the simulated value of the maximum conversion current of the multi-terminal dc system includes: if the random calculation error is a first proportional coefficient, calculating a product of the multi-terminal direct-current maximum conversion current approximate value and the first proportional coefficient, and obtaining a maximum conversion current simulation value of the multi-terminal direct-current system according to the product; and if the random calculation error is a second proportional coefficient, calculating a quotient of the multi-terminal direct current maximum conversion current approximate value and the second proportional coefficient, and obtaining a maximum conversion current simulation value of the multi-terminal direct current system according to the quotient.
In all the embodiments, the impedance range of each variable resistor of the multi-terminal direct current system is obtained; selecting a plurality of resistance values of each variable resistor in the impedance range of each variable resistor, and calculating through the first calculation model to obtain a plurality of corresponding conversion current values; determining a maximum value from the plurality of conversion current values as an approximate value of the multi-terminal direct current maximum conversion current; obtaining a random calculation error according to the obtained accurate value of the maximum direct current conversion current at the two ends and the obtained approximate value of the maximum direct current conversion current at the two ends; and correcting the error of the approximate value of the maximum conversion current of the multi-terminal direct current according to the random calculation error to obtain a maximum conversion current simulation value of the multi-terminal direct current system. The method can effectively avoid the trouble of accurately determining the working condition of the multi-terminal direct current maximum conversion current, has simple process, and can quickly determine the maximum conversion current calculation value suitable for engineering application.
It should be noted that, in the above embodiment of the system for simulating the maximum conversion current of the multi-terminal dc system, because the contents of information interaction, execution process, and the like between the modules/units are based on the same concept as the foregoing method embodiment of the present invention, the technical effect brought by the above embodiment is the same as the foregoing method embodiment of the present invention, and specific contents may refer to the description in the method embodiment of the present invention, and are not described again here.
In addition, in the above exemplary embodiment of the system for simulating the maximum conversion current of the multi-terminal dc system, the logic division of each program module is only an example, and in practical applications, the above function distribution may be performed by different program modules according to needs, for example, due to the configuration requirements of corresponding hardware or the convenience of implementation of software, that is, the internal structure of the system for simulating the maximum conversion current of the multi-terminal dc system is divided into different program modules to perform all or part of the above described functions.
It will be understood by those skilled in the art that all or part of the processes of the methods of the above embodiments may be implemented by a computer program, which is stored in a computer readable storage medium and sold or used as a stand-alone product. The program, when executed, may perform all or a portion of the steps of the embodiments of the methods described above. In addition, the storage medium may be provided in a computer device, and the computer device further includes a processor, and when the processor executes the program in the storage medium, all or part of the steps of the embodiments of the methods described above can be implemented. The storage medium may be a magnetic disk, an optical disk, a Read-Only Memory (ROM), a Random Access Memory (RAM), or the like.
In the above embodiments, the descriptions of the respective embodiments have respective emphasis, and for parts that are not described in detail in a certain embodiment, reference may be made to related descriptions of other embodiments. It will be understood that the terms "first," "second," and the like as used herein are used herein to distinguish one object from another, but the objects are not limited by these terms.
The above-described examples merely represent several embodiments of the present invention and should not be construed as limiting the scope of the invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the inventive concept, which falls within the scope of the present invention. Therefore, the protection scope of the present patent shall be subject to the appended claims.
Claims (10)
1. A method for simulating a maximum converted current of a multi-terminal dc system, comprising:
determining a first calculation model of the conversion current of the multi-terminal direct current system according to system conditions, and determining the resistance value range of each variable resistor in the first calculation model; the first computational model includes: the device comprises a multi-terminal random signal generator, a multi-terminal simulation circuit and a multi-terminal maximum value acquisition module; each resistance signal output end of the multi-end random signal generator is correspondingly connected with the resistance signal input end of each variable resistor in the multi-end analog-to-digital converter, and the conversion current target signal output end of the multi-end analog-to-digital converter is connected with the input end of the multi-end maximum value acquisition module;
selecting a plurality of resistance values of each variable resistor according to the resistance value range of each variable resistor, and calculating through the first calculation model to obtain a plurality of corresponding conversion current values;
determining a maximum value from the plurality of conversion current values as an approximate value of the multi-terminal direct current maximum conversion current;
acquiring a two-end direct current maximum conversion current accurate value and a two-end direct current maximum conversion current approximate value of a two-end direct current system which are determined in advance, and obtaining a random calculation error according to the two-end direct current maximum conversion current accurate value and the two-end direct current maximum conversion current approximate value; the two-end direct current maximum conversion current approximate value is calculated through a second calculation model of the conversion current of the two-end direct current system; the second computational model includes: the device comprises a two-end random signal generator, a two-end simulation circuit and a two-end maximum value acquisition module; each resistance signal output end of the random signal generators at the two ends is correspondingly connected with the resistance signal input end of each variable resistor in the simulation analog circuits at the two ends, and the conversion current target signal output end of the simulation analog circuits at the two ends is connected with the input end of the maximum value acquisition module at the two ends;
and correcting the error of the approximate value of the maximum conversion current of the multi-terminal direct current according to the random calculation error to obtain a maximum conversion current simulation value of the multi-terminal direct current system.
2. The method of claim 1, wherein the selecting a plurality of resistance values of each variable resistor according to the resistance value range of each variable resistor, and calculating a plurality of corresponding conversion current values through the first calculation model respectively comprises:
setting the calculation times of the first calculation model as preset calculation times;
selecting one resistance value of each variable resistor every time in the resistance value range of each variable resistor in the first calculation model, and forming a group of resistance values by one resistance value of each variable resistor; calculating to obtain conversion current values corresponding to the resistance values of all groups through the first calculation model, and accumulating the current calculation times by 1 after each calculation to obtain the corresponding conversion current values;
and if the current calculation times reach the preset calculation times, stopping the calculation.
3. The method for simulating the maximum conversion current of the multi-terminal dc system according to claim 2, wherein the step of stopping the calculation if the current calculation number reaches the preset calculation number comprises:
if the current calculation times are less than the preset calculation times, jumping to the resistance range of each variable resistor in the first calculation model, reselecting one resistance of each variable resistor, and forming a group of resistances by one resistance of each variable resistor; and calculating to obtain a conversion current value corresponding to the group of resistance values through the first calculation model, and accumulating the current calculation times by 1 after the corresponding conversion current value is obtained through the calculation.
4. The method for simulating maximum converted current of a multi-terminal dc system according to claim 1, wherein the step of obtaining the predetermined accurate value and approximate value of the maximum converted current of the two-terminal dc system comprises:
determining a second calculation model of the conversion current of the two-end direct current system, and determining the resistance value range of each variable resistor in the second calculation model;
determining the accurate value of the maximum direct current conversion current at the two ends of the direct current system at the two ends through the second calculation model within the resistance value range of each variable resistor in the second calculation model;
selecting a plurality of resistance values of each variable resistor according to the resistance value range of each variable resistor in the second calculation model, and calculating through the second calculation model to obtain a plurality of corresponding conversion current values;
and determining the maximum value from the plurality of conversion current values as the approximate value of the maximum direct current conversion current at the two ends.
5. The method of claim 4, wherein the selecting a plurality of resistance values of each variable resistor according to the resistance value range of each variable resistor in the second calculation model, and calculating a plurality of corresponding conversion current values through the second calculation model respectively comprises:
setting the calculation times of the second calculation model;
selecting one resistance value of each variable resistor every time in the resistance value range of each variable resistor in the second calculation model, and forming a group of resistance values by one resistance value of each variable resistor; calculating to obtain conversion current values corresponding to the resistance values of all groups through the second calculation model; after the corresponding conversion current value is obtained by each calculation, accumulating the current calculation times by 1;
and if the current calculation times reach the calculation times, stopping calculation and counting the conversion current values.
6. The method of claim 1, wherein the obtaining a random calculation error according to the accurate value of the maximum conversion current between two terminals and the approximate value of the maximum conversion current between two terminals comprises:
calculating the ratio of the accurate value of the maximum direct conversion current at the two ends to the approximate value of the maximum direct conversion current at the two ends, and obtaining a first proportional coefficient according to the ratio;
and/or the presence of a gas in the gas,
and calculating the ratio of the approximate value of the maximum direct current conversion current at the two ends to the accurate value of the maximum direct current conversion current at the two ends, and obtaining a second proportionality coefficient according to the ratio.
7. The method according to claim 6, wherein the error correcting the maximum conversion current approximation value according to the random calculation error to obtain the maximum conversion current simulation value of the multi-terminal dc system comprises:
if the random calculation error is a first proportional coefficient, calculating a product of the multi-terminal direct-current maximum conversion current approximate value and the first proportional coefficient, and obtaining a maximum conversion current simulation value of the multi-terminal direct-current system according to the product;
and if the random calculation error is a second proportional coefficient, calculating a quotient of the multi-terminal direct current maximum conversion current approximate value and the second proportional coefficient, and obtaining a maximum conversion current simulation value of the multi-terminal direct current system according to the quotient.
8. A maximum converted current system for emulating a multi-terminal dc system, comprising:
the model determining module is used for determining a first calculation model of the conversion current of the multi-terminal direct-current system and determining the resistance value range of each variable resistor in the first calculation model according to system conditions; the first computational model includes: the device comprises a multi-terminal random signal generator, a multi-terminal simulation circuit and a multi-terminal maximum value acquisition module; each resistance signal output end of the multi-end random signal generator is correspondingly connected with the resistance signal input end of each variable resistor in the multi-end analog-to-digital converter, and the conversion current target signal output end of the multi-end analog-to-digital converter is connected with the input end of the multi-end maximum value acquisition module;
the calculation module is used for selecting a plurality of resistance values of each variable resistor according to the resistance value range of each variable resistor, and calculating to obtain a plurality of corresponding conversion current values through the first calculation model respectively;
an approximate value determining module, configured to determine a maximum value from the multiple conversion current values, as an approximate value of the multi-terminal dc maximum conversion current;
the error calculation module is used for acquiring a predetermined two-end direct current maximum conversion current accurate value and a two-end direct current maximum conversion current approximate value of the two-end direct current system, and obtaining a random calculation error according to the two-end direct current maximum conversion current accurate value and the two-end direct current maximum conversion current approximate value; the two-end direct current maximum conversion current approximate value is calculated through a second calculation model of the conversion current of the two-end direct current system; the second computational model includes: the device comprises a two-end random signal generator, a two-end simulation circuit and a two-end maximum value acquisition module; each resistance signal output end of the random signal generators at the two ends is correspondingly connected with the resistance signal input end of each variable resistor in the simulation analog circuits at the two ends, and the conversion current target signal output end of the simulation analog circuits at the two ends is connected with the input end of the maximum value acquisition module at the two ends;
and the error correction module is used for carrying out error correction on the multi-terminal direct current maximum conversion current approximate value according to the random calculation error to obtain a maximum conversion current simulation value of the multi-terminal direct current system.
9. A computer-readable storage medium, on which a computer program is stored which, when being executed by a processor, carries out the steps of the method of simulating a maximum converted current of a multi-terminal dc system according to any one of claims 1 to 7.
10. A computer device comprising a memory, a processor and a computer program stored on said memory and executable on said processor, characterized in that said processor, when executing said program, carries out the steps of the method of simulating maximum converted current of a multi-terminal dc system according to any one of claims 1 to 7.
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