CN113312878B - Flexible direct current conversion bus short-circuit current calculation method, device, terminal and medium - Google Patents
Flexible direct current conversion bus short-circuit current calculation method, device, terminal and medium Download PDFInfo
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Abstract
The invention discloses a flexible direct current conversion bus short-circuit current calculation method, a flexible direct current conversion bus short-circuit current calculation device, a flexible direct current conversion bus short-circuit current calculation terminal and a flexible direct current conversion bus short-circuit current calculation medium, wherein the method comprises the steps of obtaining electromechanical transient simulation data and a first operation mode of a flexible direct current-alternating current side system; calculating a short circuit current vector value of a flexible direct current-alternating current side system, equivalent impedance from the equivalent to a flexible direct current conversion bus, an impedance phase angle of the equivalent impedance and a three-phase short circuit current amplitude value in a first operation mode; acquiring a second operation mode of the flexible-straight system according to the flexible-straight electromagnetic transient simulation model; calculating short-circuit current provided by the flexible-straight system in the second operation mode based on the actual flexible-straight electromagnetic model; and matching the second operation mode with the corresponding first operation mode, and calculating the short-circuit current in the first operation mode according to the short-circuit current provided by the flexible direct system. The invention considers the matching relation of the short-circuit current amplitude and phase provided by the flexible direct system under different control modes and fixed values and the operation modes among different systems, and improves the accuracy of the short-circuit current calculation result.
Description
Technical Field
The invention relates to the technical field of flexible direct current transmission, in particular to a flexible direct current conversion bus short-circuit current calculation method, device, terminal and medium.
Background
Short-circuit current calculation is one of important contents of power system analysis, and is the basis of work such as power system planning design, relay protection setting calculation, electrical equipment selection and verification. In recent years, with the development of a power grid technology, a flexible direct current transmission (VSC-HVDC) technology is more and more favored, and the flexible direct current transmission technology has increasingly wide engineering application at home and abroad by virtue of the advantages of flexible power control, quick regulation capability and capability of transmitting power for passive systems and isolated islands. With the continuous maturation of the flexible direct current technology and the improvement of the voltage level of the flexible direct current transmission engineering connected to the flexible direct current and alternating current side system, the influence of the flexible direct current transmission on the short-circuit current of the flexible direct current and alternating current side system cannot be ignored.
At present, common engineering short-circuit current calculation methods for flexible direct current access systems include the following steps: the first method is to directly calculate without flexible direct current influence; the second one is to adopt a numerical value superposition method, consider that the flexible direct current can provide short-circuit current, the current amplitude is the current converter amplitude limiting value, ignore the phase difference between the current amplitude and the alternating short-circuit current, and carry out amplitude superposition on the short-circuit current component provided by the flexible direct current and the alternating short-circuit current component; and the third method adopts a simplified vector method, can take account of the influence of a flexible direct current fault current limiting mode, and can simplify the phase relation between a flexible direct current short-circuit current component and an alternating current short-circuit current component.
However, the existing methods can only roughly calculate the short-circuit current generated by the flexible direct-current transmission, because the methods neglect the influence of the power direction and the active current component, the level of the flexible direct-current contribution short-circuit current under different control modes and fixed values is not refined, and meanwhile, the coordination relationship between the flexible direct-current and alternating-current side system operation mode and the flexible direct-current operation mode and control is not considered, so that the calculation result often has a large error.
Disclosure of Invention
The invention aims to provide a flexible direct current conversion bus short-circuit current calculation method, a flexible direct current conversion bus short-circuit current calculation device, a flexible direct current conversion bus short-circuit current calculation terminal and a flexible direct current conversion bus short-circuit current calculation medium, and aims to solve the technical problem of large error in the existing calculation method.
In order to overcome the defects in the prior art, the invention provides a flexible direct current conversion bus short-circuit current calculation method, which comprises the following steps:
acquiring electromechanical transient simulation data and a first operation mode of a flexible direct current-alternating current side system;
according to simulation data, calculating a short-circuit current vector value of a flexible direct current-alternating current side system, equivalent impedance from the equivalent to a flexible direct current conversion bus, an impedance phase angle of the equivalent impedance and a three-phase short-circuit current amplitude value in a first operation mode;
acquiring a second operation mode of the flexible-straight system according to the flexible-straight electromagnetic transient simulation model;
calculating short-circuit current provided by the flexible-straight system in the second operation mode based on the actual flexible-straight electromagnetic model;
and matching the second operation mode with the corresponding first operation mode, and calculating the short-circuit current in the first operation mode according to the short-circuit current provided by the flexible direct current system to serve as the short-circuit current of the flexible direct current conversion bus.
Further, the calculating the short-circuit current provided by the flexible direct system in the second operation mode based on the actual flexible direct electromagnetic model includes:
based on the actual flexible-direct electromagnetic model, simulating the current and the phase angle of the flexible-direct system flowing to the short-circuit point when the three-phase short-circuit fault occurs on the current conversion bus in the second operation mode;
and calculating the short-circuit current provided by the flexible direct current system in the second operation mode by utilizing the phase angle of the equivalent voltage source of the flexible direct current-alternating current side system, the current and the phase angle of the flexible direct current system flowing to the short-circuit point.
Further, after the calculating the short-circuit current in the first operation mode as the short-circuit current of the flexible direct current bus, the method further includes:
calculating the maximum value of the short-circuit current of the flexible direct current conversion bus;
and adding a reliable coefficient to the maximum value to obtain a check value, and judging whether the on-off capacity of the breaker at the outlet end of the flexible direct current conversion bus meets the preset condition or not by using the check value.
Further, the first operation mode comprises a full-wiring operation mode and a different N-1 or N-2 disconnection operation mode.
Further, the second operation mode includes: various outer loop control mode combinations and fixed values, and corresponding AC/DC filter input modes.
Further, the electromechanical transient simulation data comprises: tidal current data and stability data.
The invention also provides a flexible direct current conversion bus short-circuit current calculating device, which comprises:
the system comprises a first operation mode acquisition unit, a second operation mode acquisition unit and a control unit, wherein the first operation mode acquisition unit is used for acquiring electromechanical transient simulation data of a flexible direct current-alternating current side system and a first operation mode;
the parameter calculation unit is used for calculating a short-circuit current vector value of the flexible direct current-alternating current side system, equivalent impedance from the equivalent to the flexible direct current-alternating current bus, an impedance phase angle of the equivalent impedance and a three-phase short-circuit current amplitude value in a first operation mode according to simulation data;
the second operation mode acquisition unit is used for acquiring a second operation mode of the flexible-direct system according to the flexible-direct electromagnetic transient simulation model;
the first current calculating unit is used for calculating the short-circuit current provided by the flexible-straight system in the second operation mode based on the actual flexible-straight electromagnetic model;
and the second current calculating unit is used for matching the second operation mode with the corresponding first operation mode, and calculating the short-circuit current in the first operation mode according to the short-circuit current provided by the flexible direct current system to serve as the flexible direct current conversion bus short-circuit current.
Further, the first current calculating unit is further configured to:
based on the actual flexible-straight electromagnetic model, simulating the current and the phase angle of the flexible-straight system flowing to the short-circuit point when the current conversion bus has a three-phase short-circuit fault in the second operation mode of the flexible-straight system;
and calculating the short-circuit current provided by the flexible direct current system in the second operation mode by utilizing the phase angle of the equivalent voltage source of the flexible direct current-alternating current side system, the current and the phase angle of the flexible direct current system flowing to the short-circuit point.
The present invention also provides a terminal device, comprising:
one or more processors;
a memory coupled to the processor for storing one or more programs;
when executed by the one or more processors, the one or more programs cause the one or more processors to implement the method for calculating the short-circuit current of the flexible direct current converting bus as described in any one of the above.
The invention also provides a computer readable storage medium, on which a computer program is stored, where the computer program is executed by a processor to implement the method for calculating the short-circuit current of the flexible direct-current converting bus according to any one of the above-mentioned items.
Compared with the prior art, the invention has the beneficial effects that:
according to the method, the matching relation between the flexible direct current-alternating current side system operation mode and the flexible direct current operation mode and control is calculated, the vector superposition relation of short-circuit current components provided by the flexible direct current side and the alternating current side of the flexible direct current system under different control modes and fixed values can be accurately calculated, and therefore the accuracy of calculation of the short-circuit current of the flexible direct current-alternating current bus is improved. The method fully considers the short-circuit current amplitude and phase provided by the flexible-straight system under different control modes and fixed values; and the matching relation between the flexible direct current running mode and the flexible direct current side system running mode is also considered, so that the short-circuit current level of the flexible direct current conversion bus is more accurately evaluated.
Drawings
In order to more clearly illustrate the technical solution of the present invention, the drawings required to be used in the embodiments will be briefly described below, and obviously, the drawings in the following description are only some embodiments of the present invention, and other drawings can be obtained by those skilled in the art without creative efforts.
Fig. 1 is a schematic flow chart of a method for calculating a short-circuit current of a flexible direct current conversion bus according to an embodiment of the present invention;
fig. 2 is a schematic diagram illustrating a current provided by a receiving-end ac system of a flexible-direct-current inverter station domain to a fault short-circuit point according to an embodiment of the present invention;
fig. 3 is a schematic structural diagram of a device for calculating a short-circuit current of a flexible direct-current bus according to an embodiment of the present invention.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
It should be understood that the step numbers used herein are for convenience of description only and are not intended as limitations on the order in which the steps are performed.
It is to be understood that the terminology used in the description of the invention herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used in the specification of the present invention and the appended claims, the singular forms "a," "an," and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise.
The terms "comprises" and "comprising" indicate the presence of the described features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof.
The term "and/or" refers to and includes any and all possible combinations of one or more of the associated listed items.
In a first aspect:
referring to fig. 1, an embodiment of the present invention provides a method for calculating a short-circuit current of a flexible direct current conversion bus, including:
s10, acquiring electromechanical transient simulation data and a first operation mode of a flexible direct current-alternating current side system;
in the step, mainly acquiring electromechanical transient simulation data of an actual flexible direct current-alternating current side system and a possible first operation mode of the actual flexible direct current-alternating current side system;
in a certain embodiment, the electromechanical transient simulation data includes power flow data and stability data;
in one embodiment, the first operation mode comprises a flexible direct current-alternating current side system full-wiring operation mode and various N-1 and N-2 disconnection operation modes.
S20, calculating a short-circuit current vector value, equivalent impedance from the equivalent to a flexible direct current conversion bus, an impedance phase angle of the equivalent impedance and a three-phase short-circuit current amplitude value of the flexible direct current-alternating current side system in a first operation mode according to simulation data;
in this step, a batch scan is first performed using a harmonic impedance equivalence program, such as the NIMSCAN program of temsin, canada, to obtain the equivalent impedance of the flexible dc-ac side system to the flexible dc-ac bus under different operating modes. Wherein, the equivalent impedance comprises a resistance value R and a reactance value X, and an impedance phase angle is calculated by adopting a formula (1):
finally, the operation mode of the flexible direct current-alternating current side system, the equivalent impedance and the value of the impedance phase angle are counted into the form of the following table 1:
TABLE 1 Flexible DC-AC side System operating mode, equivalent impedance and impedance phase Angle List
| Flexible direct current-alternating current side system operation mode | Real equivalent impedance (R) | Equivalent impedance imaginary part (X) | Impedance phase angle (PH) |
| Mode 1 | R1 | X1 | PH1 |
| Mode 2 | R2 | X2 | PH2 |
| Mode 3 | R3 | X3 | PH3 |
| ... | ... | ... | ... |
Then, a short-circuit current calculation program, such as a PSD-SCCP program of the institute of electrical power science in china, is used for batch scanning to obtain three-phase short-circuit current amplitudes of the flexible-direct-current bus of the flexible-direct-current side system in different operation modes, and statistics is shown in the following table 2:
table 2 list of operation mode and three-phase short-circuit current amplitude of flexible dc-ac side system
| Flexible direct current-alternating current side system operation mode | I km |
| Mode 1 | I km1 |
| Mode 2 | I km2 |
| Mode 3 | I km3 |
| ... | ... |
Further, the short-circuit current vector values provided by the flexible direct current-alternating current side system in each operation mode are theoretically calculated and are counted into the form shown in table 3 below. Wherein the calculation formula is as follows:
table 3 flexible dc-ac system operation mode and short-circuit current vector value list
S30, acquiring a second operation mode of the flexible-straight system according to the flexible-straight electromagnetic transient simulation model;
it should be noted that, in this step, the actual soft and straight electromagnetic transient simulation model is first obtained. Generally, actual flexible engineering builds a detailed electromagnetic model on an EMTDC/PSCAD platform, and then implements the method described below based on the platform.
Specifically, a second operation mode that may exist in the actual flexible-direct system is obtained, and in a certain embodiment, the second operation mode mainly includes various outer loop control mode combinations and fixed values, and a corresponding ac/dc filter input mode.
Wherein the control mode comprises constant DC voltage (U) dc ) Constant active power (P) and constant alternating voltage (U) ac ) Constant reactive power (Q); the control modes are combined into four types, which are respectively as follows: (1) decide U dc And decide U ac (ii) a (2) Decide U dc And determining Q; (3) decide P and decide U ac (ii) a (4) P and Q are determined;
in addition, the control constant value is a reference value possibly existing in each control mode and comprises a direct-current voltage reference value U dcref Active reference value P ref Reference value U of AC voltage acref Reactive reference value Q ref (ii) a Wherein U is dcref And U acref Generally, 1.0pu is adopted, and the modification can be performed according to the actual engineering setting value, and 1.0pu is preferably adopted in this embodiment. Finally, all the operation modes of the flexible direct system can be counted as the following form 4:
table 4 list of the operation mode and the ac/dc filter input mode of the soft and straight system
S40, calculating short-circuit current provided by the flexible-straight system in the second operation mode based on the actual flexible-straight electromagnetic model;
in this step, two steps are specifically included:
a) Based on an actual flexible direct electromagnetic model on an EMTDC/PSCAD platform, the batch processing calculation function of PSCAD software is adopted to respectively simulate the current value flowing to a short-circuit point of the flexible direct system under different operation modes and reference values of the flexible direct system and when a three-phase short-circuit fault occurs in a current conversion bus. As shown in FIG. 2, the internal impedance of the flexible DC-AC side system adopts a pure inductance PCC point as a flexible DC-AC bus, I vsc Current in soft DC direction to short-circuit point, I kac For the current flowing to the short-circuit point on the system side of the flexible direct current and alternating current side, the reference directions are all the current flowing to the short-circuit point. Wherein, the 0.1s moment I after the short-circuit fault occurs is recorded vsc 、I kac The amplitude and phase angle of (c) are: i is vsc 、θ vsc 、I kac 、θ kac (ii) a In general, I may be vsc Is denoted as I vsc ∠θ vsc (ii) a Will I kac Is denoted as I kac ∠θ kac . The internal impedance of the flexible direct current-alternating current side system adopts a constant value in simulation, and is recorded as Z S ＝R S +jX S 。
b) Calculating a short-circuit current phase angle and a phasor value which are provided by flexible and direct by taking the phase angle of the equivalent voltage source of the flexible and direct current side system as a reference:
then repeating a) -b), obtaining the flexible and straight system under different operation modes and reference values
Values, statistics are in the form of table 5 below:
TABLE 5 Flexible and straight system under different operation modes and reference values
Value of
And S50, matching the second operation mode with the corresponding first operation mode, and calculating the short-circuit current in the first operation mode according to the short-circuit current provided by the flexible-direct current system to serve as the short-circuit current of the flexible-direct current conversion bus.
The method specifically comprises the following steps:
a) Selecting a certain flexible direct system operation mode, recording the mode m (the mode m can adopt a mode 1-1, a mode 2-1 and a mode 2-2.), acquiring the flexible direct current and alternating current side system operation modes possibly existing corresponding to the flexible direct system operation mode m, recording the flexible direct current and alternating current side system operation modes as { mode n }, wherein { mode n } comprises n flexible direct current and alternating current side system operation modes, and utilizing n cycles to obtain the maximum value in the following formula, and recording the maximum value as the maximum value
B) And repeatedly executing the step A), wherein the mode m is respectively a mode 1-1, a mode 2-2. Until all I are found kmax Values, statistics are in the form of table 6 below:
TABLE 6 Flex-straight system I under different operation modes and reference values kmax Value of
| Operation mode of flexible and straight system | I kmax |
| Mode 1-1 | I kmax .1 |
| Mode 2-1 | I kmax .2 |
| Mode 2-2 | I kmax .3 |
| ... | ... |
Wherein, I kmax I.e. the flexible direct current bus short circuit current.
In one embodiment, to evaluate the short-circuit current level of the flexible direct-current bus, I is first calculated according to step S50 kmax Calculating the maximum value I 'of short-circuit current of the flexible direct-current conversion bus' kmax ＝max(I kmax.m ). Then utilize l' kmax Plus a reliability factor, e.g. 1.05I' kmax And the value is used for verifying whether the breaking capacity of the breaker at the outlet end of the flexible direct current conversion bus meets the requirementAnd (4) requiring.
The calculation method provided by the embodiment of the invention takes into account the matching relation between the flexible-direct-current-alternating-current-side system operation mode and the flexible-direct-current operation mode and control, and can accurately calculate the vector superposition relation of short-circuit current components provided by the flexible-direct-current side and the alternating-current side of the flexible-direct-current-alternating-current system under different control modes and fixed values, thereby improving the accuracy of calculation of the short-circuit current of the flexible-direct-current-alternating-current bus. The method fully considers the short-circuit current amplitude and phase provided by the flexible-straight system under different control modes and fixed values; and the matching relation between the flexible direct current running mode and the flexible direct current side system running mode is also considered, so that the short-circuit current level of the flexible direct current conversion bus is more accurately evaluated.
In a second aspect:
referring to fig. 3, an embodiment of the present invention further provides a device for calculating a short-circuit current of a flexible direct current converting bus, including:
the first operation mode acquisition unit 01 is used for acquiring electromechanical transient simulation data of the flexible direct current-alternating current side system and a first operation mode;
the parameter calculation unit 02 is used for calculating a short-circuit current vector value of the flexible direct current-alternating current side system, equivalent impedance from the equivalent to the flexible direct current conversion bus, an impedance phase angle of the equivalent impedance and a three-phase short-circuit current amplitude value in a first operation mode according to simulation data;
the second operation mode obtaining unit 03 is configured to obtain a second operation mode of the flexible-direct system according to the flexible-direct electromagnetic transient simulation model;
the first current calculating unit 04 is used for calculating short-circuit current provided by the flexible-straight system in the second operation mode based on the actual flexible-straight electromagnetic model;
and the second current calculating unit 05 is configured to match the second operation mode with the corresponding first operation mode, and calculate the short-circuit current in the first operation mode according to the short-circuit current provided by the flexible direct current system, as the flexible direct current conversion bus short-circuit current.
Further, the first current calculating unit is further configured to:
based on the actual flexible-straight electromagnetic model, simulating the current and the phase angle of the flexible-straight system flowing to the short-circuit point when the current conversion bus has a three-phase short-circuit fault in the second operation mode of the flexible-straight system;
and calculating the short-circuit current provided by the flexible direct current system in the second operation mode by utilizing the phase angle of the equivalent voltage source of the flexible direct current-alternating current side system, the current and the phase angle of the flexible direct current system flowing to the short-circuit point.
The calculating device provided by the embodiment of the invention takes the matching relation between the flexible direct current and alternating current side system operation mode and the flexible direct current operation mode and control into account, and can accurately calculate the vector superposition relation of short-circuit current components provided by the flexible direct current side and the alternating current side of the flexible direct current system under different control modes and fixed values, thereby improving the accuracy of calculating the short-circuit current of the flexible direct current conversion bus. The method fully considers the short-circuit current amplitude and phase provided by the flexible direct system under different control modes and fixed values; and the matching relation between the flexible direct current running mode and the flexible direct current side system running mode is also considered, so that the short-circuit current level of the flexible direct current conversion bus is more accurately evaluated.
In a third aspect:
an embodiment of the present invention further provides a terminal device, including:
one or more processors;
a memory coupled to the processor for storing one or more programs;
when executed by the one or more processors, cause the one or more processors to implement the method for calculating a short circuit current of a flexible direct current bus as described above.
The processor is used for controlling the overall operation of the terminal equipment so as to complete all or part of the steps of the flexible direct current conversion bus short-circuit current calculation method. The memory is used to store various types of data to support operation at the terminal device, and these data may include, for example, instructions for any application or method operating on the terminal device, as well as application-related data. The Memory may be implemented by any type of volatile or non-volatile Memory device or combination thereof, such as Static Random Access Memory (SRAM), electrically Erasable Programmable Read-Only Memory (EEPROM), erasable Programmable Read-Only Memory (EPROM), programmable Read-Only Memory (PROM), read-Only Memory (ROM), magnetic Memory, flash Memory, magnetic disk, or optical disk.
The terminal Device may be implemented by one or more Application Specific 1 integrated circuits (AS 1C), digital Signal Processors (DSP), digital Signal Processing Devices (DSPD), programmable Logic Devices (PLD), field Programmable Gate Arrays (FPGA), controllers, microcontrollers, microprocessors, or other electronic components, and is configured to perform the method for calculating the short-Circuit current of the flexible direct current converter bus according to any one of the embodiments described above, and achieve the technical effects consistent with the above methods.
An embodiment of the present invention further provides a computer readable storage medium including program instructions, where the program instructions, when executed by a processor, implement the steps of the method for calculating a short-circuit current of a flexible direct-current bus according to any one of the embodiments described above. For example, the computer readable storage medium may be the above-mentioned memory including program instructions, and the above-mentioned program instructions may be executed by a processor of a terminal device to implement the method for calculating a short-circuit current of a flexible direct current bus according to any one of the above-mentioned embodiments, and achieve technical effects consistent with the above-mentioned method.
While the foregoing is directed to the preferred embodiment of the present invention, it will be understood by those skilled in the art that various changes and modifications may be made without departing from the spirit and scope of the invention.
Claims (8)
1. A flexible direct current conversion bus short-circuit current calculation method is characterized by comprising the following steps:
acquiring electromechanical transient simulation data and a first operation mode of a flexible direct current-alternating current side system; the first operation mode comprises a full-wiring operation mode and different N-1 or N-2 disconnection operation modes;
according to simulation data, calculating a short-circuit current vector value of a flexible direct current-alternating current side system, equivalent impedance from the equivalent to a flexible direct current conversion bus, an impedance phase angle of the equivalent impedance and a three-phase short-circuit current amplitude value under different first operation modes;
acquiring a second operation mode of the flexible-straight system according to the flexible-straight electromagnetic transient simulation model; the second operation mode includes: various outer ring control mode combinations and fixed values, and corresponding AC/DC filter input modes;
calculating short-circuit current provided by the flexible-straight system under different second operation modes based on the actual flexible-straight electromagnetic model;
obtaining a certain second operation mode, obtaining n first operation modes corresponding to the current second operation mode, and solving the maximum value I in the following formula by utilizing n times of circulation k max.j ：
In the formula (I), the compound is shown in the specification,
j is more than or equal to 1 and less than or equal to m for the current of the flexible direct current short-circuit point in the jth second operation mode; from
I is more than or equal to 1 and less than or equal to n, and the current flows to the short circuit point from the system side of the flexible direct current and alternating current side in the ith first operation mode;
determination of I kmax ，I kmax ＝{I kmax.1 、I kmax.2 、...I kmax.j J is more than or equal to 1 and less than or equal to m; will I kmax As a soft-dc converter bus short-circuit current.
2. The method for calculating the short-circuit current of the flexible-direct current converting bus according to claim 1, wherein calculating the short-circuit current provided by the flexible-direct system in the second operation mode based on the actual flexible-direct electromagnetic model comprises:
based on the actual flexible-straight electromagnetic model, simulating the current and the phase angle of the flexible-straight system flowing to the short-circuit point when the current conversion bus has a three-phase short-circuit fault in the second operation mode of the flexible-straight system;
and calculating the short-circuit current provided by the flexible direct current system under the second operation mode by utilizing the phase angle of the equivalent voltage source of the flexible direct current-alternating current side system, the current and the phase angle of the flexible direct current system flowing to the short-circuit point.
3. The method according to claim 1, further comprising, after calculating the short-circuit current in the first operating mode as the short-circuit current in the flexible direct-current bus, the step of:
calculating the maximum value of the short-circuit current of the flexible direct current conversion bus;
and adding a reliable coefficient to the maximum value to obtain a check value, and judging whether the on-off capacity of the breaker at the outlet end of the flexible direct current conversion bus meets the preset condition or not by using the check value.
4. The flexible direct current converter bus short-circuit current calculation method according to claim 1, wherein the electromechanical transient simulation data comprises: tidal current data and stability data.
5. A device for calculating a short circuit current of a flexible direct current converting bus, comprising:
the first operation mode acquisition unit is used for acquiring electromechanical transient simulation data of the flexible direct current-alternating current side system and a first operation mode; the first operation mode comprises a full-wiring operation mode and different N-1 or N-2 disconnection operation modes;
the parameter calculation unit is used for calculating a short-circuit current vector value of the flexible direct current-alternating current side system, equivalent impedance from the equivalent to the flexible direct current conversion bus, an impedance phase angle of the equivalent impedance and a three-phase short-circuit current amplitude value in different first operation modes according to simulation data;
the second operation mode acquisition unit is used for acquiring a second operation mode of the flexible-direct system according to the flexible-direct electromagnetic transient simulation model; the second operation mode comprises the following steps: various outer ring control mode combinations and fixed values, and corresponding AC/DC filter input modes;
the first current calculating unit is used for calculating short-circuit current provided by the flexible-direct system under different second operation modes based on the actual flexible-direct electromagnetic model;
a second current calculating unit for obtaining a certain second operation mode, obtaining n first operation modes corresponding to the current second operation mode, and calculating the maximum value I in the following formula by using n times of circulation kmax.j ：
In the formula (I), the compound is shown in the specification,
j is more than or equal to 1 and less than or equal to m for the current of the flexible direct current short-circuit point in the jth second operation mode; from
I is more than or equal to 1 and less than or equal to n, and the current flows to the short circuit point from the system side of the flexible direct current and alternating current side in the ith first operation mode;
determination of I kmax ，I kmax ＝{I kmax.1 、I kmax.2 、...I kmax.j J is more than or equal to 1 and less than or equal to m; will I kmax As a soft-dc converter bus short-circuit current.
6. The flexible direct current bus short-circuit current calculation device according to claim 5, wherein the first current calculation unit is further configured to:
based on the actual flexible-straight electromagnetic model, simulating the current and the phase angle of the flexible-straight system flowing to the short-circuit point when the current conversion bus has a three-phase short-circuit fault in the second operation mode of the flexible-straight system;
and calculating the short-circuit current provided by the flexible direct current system under the second operation mode by utilizing the phase angle of the equivalent voltage source of the flexible direct current-alternating current side system, the current and the phase angle of the flexible direct current system flowing to the short-circuit point.
7. A terminal device, comprising:
one or more processors;
a memory coupled to the processor for storing one or more programs;
when executed by the one or more processors, cause the one or more processors to implement the method of calculating a short circuit current for a flexible direct current bus as claimed in any one of claims 1 to 4.
8. A computer-readable storage medium having a computer program stored thereon, the computer program being executable by a processor to implement the method of calculating a short-circuit current of a flexible direct current bus according to any one of claims 1 to 4.
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Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109004638A (en) * | 2018-06-29 | 2018-12-14 | 中国电力科学研究院有限公司 | A kind of flexible direct current engineering electromechanics-electromagnetism hybrid simulation method and system |
| CN110148065A (en) * | 2019-04-11 | 2019-08-20 | 国家电网公司华中分部 | It is a kind of to consider the soft calculation of short-circuit current processing method and system directly influenced |
| CN110247417A (en) * | 2019-07-02 | 2019-09-17 | 国网江苏省电力有限公司经济技术研究院 | A kind of control method reducing both ends flexible direct-current transmission system converter station short circuit current |
| CN110311399A (en) * | 2019-06-14 | 2019-10-08 | 中国电力科学研究院有限公司 | A kind of determination method and device of flexible direct current contribution current in the short |
| CN110456219A (en) * | 2019-08-12 | 2019-11-15 | 国网江西省电力有限公司电力科学研究院 | A kind of appraisal procedure of distribution line short voltage dip degree |
| CN111509753A (en) * | 2020-03-20 | 2020-08-07 | 中国电力科学研究院有限公司 | Method and system for controlling short-circuit current in near zone of converter station |
| CN112366666A (en) * | 2020-10-22 | 2021-02-12 | 中国电力科学研究院有限公司 | Method and system for restraining flexible direct-current near-zone single-phase short-circuit current |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7356791B2 (en) * | 2005-05-27 | 2008-04-08 | Sonnet Software, Inc. | Method and apparatus for rapid electromagnetic analysis |
| CN111697607B (en) * | 2019-03-15 | 2022-06-10 | 中国能源建设集团江苏省电力设计院有限公司 | Multi-terminal flexible direct-current transmission receiving-end power grid access method and system |
| CN112398159B (en) * | 2020-11-12 | 2023-02-28 | 南方电网科学研究院有限责任公司 | Flexible direct-current transmission alternating-current operation method, device, equipment and storage medium |
-
2021
- 2021-06-24 CN CN202110705159.3A patent/CN113312878B/en active Active
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109004638A (en) * | 2018-06-29 | 2018-12-14 | 中国电力科学研究院有限公司 | A kind of flexible direct current engineering electromechanics-electromagnetism hybrid simulation method and system |
| CN110148065A (en) * | 2019-04-11 | 2019-08-20 | 国家电网公司华中分部 | It is a kind of to consider the soft calculation of short-circuit current processing method and system directly influenced |
| CN110311399A (en) * | 2019-06-14 | 2019-10-08 | 中国电力科学研究院有限公司 | A kind of determination method and device of flexible direct current contribution current in the short |
| CN110247417A (en) * | 2019-07-02 | 2019-09-17 | 国网江苏省电力有限公司经济技术研究院 | A kind of control method reducing both ends flexible direct-current transmission system converter station short circuit current |
| CN110456219A (en) * | 2019-08-12 | 2019-11-15 | 国网江西省电力有限公司电力科学研究院 | A kind of appraisal procedure of distribution line short voltage dip degree |
| CN111509753A (en) * | 2020-03-20 | 2020-08-07 | 中国电力科学研究院有限公司 | Method and system for controlling short-circuit current in near zone of converter station |
| CN112366666A (en) * | 2020-10-22 | 2021-02-12 | 中国电力科学研究院有限公司 | Method and system for restraining flexible direct-current near-zone single-phase short-circuit current |
Non-Patent Citations (2)
| Title |
|---|
| Sensitivity analysis on short-circuit current contribution from VSC-HVDC systems connecting far and large offshore wind power plants;M Ndreko et al;《IEEE PES Innovative Smart Grid Technologies》;20141231;第1-6页 * |
| 柔性直流电网故障特性及其控制策略研究;李英彪;《中国优秀硕士学位论文全文数据库 工程科技Ⅱ辑》;20180215;第C042-931页 * |
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