CN-121995101-A - Method and device for determining direct current electric shock current for direct current distribution equipment

CN121995101ACN 121995101 ACN121995101 ACN 121995101ACN-121995101-A

Abstract

The application discloses a method and a device for determining direct current electric shock current for direct current distribution equipment, and belongs to the technical field of power grid power supply. The method comprises the steps of obtaining a plurality of line direct current in a preset time period of the direct current distribution equipment under the current working condition, determining a plurality of window line direct current corresponding to each two adjacent sliding windows in the plurality of line direct current, determining a plurality of difference values between the window direct current corresponding to each two adjacent sliding windows to obtain a plurality of window direct current difference values in the preset time period of the direct current distribution equipment under the current working condition, and determining direct current shock current in the preset time period of the direct current distribution equipment under the current working condition according to the plurality of window direct current difference values. The application can improve the calculation reliability of the direct current electric shock current.

Inventors

ZHU HONGZHANG
YANG JUEFEI
Tang Chouyao
ZUO FANG
WU CHUANPING
XIE LINJIN
GUO XIAOHAN
TAN SHUXIN
YAO CAIYUN
HU JINLI
ZHU YINXIN
OuYang Liangxuan

Assignees

国网湖南省电力有限公司
湖南防灾科技有限公司
国网湖南省电力有限公司防灾减灾中心
国家电网有限公司

Dates

Publication Date: 20260508
Application Date: 20251231

Claims (10)

1. A method for determining a direct current electric shock current for a direct current power distribution device, the method comprising: Obtaining direct current of a plurality of lines of direct current distribution equipment in a preset time period under the current working condition; Determining a plurality of window line direct current corresponding to each two adjacent sliding windows in the plurality of line direct current; Determining a plurality of difference values between the direct current of a plurality of windows corresponding to every two adjacent sliding windows to obtain a plurality of window direct current difference values of the direct current distribution equipment in a preset time period under the current working condition; And determining the direct current electric shock current of the direct current distribution equipment in a preset time period under the current working condition according to the direct current difference values of the windows.
2. The method according to claim 1, wherein determining the dc shock current of the dc distribution device in the current operating condition for the preset period of time according to the dc current difference values of the plurality of windows comprises: Under the condition that the direct current difference value of each window is larger than or equal to zero, determining the direct current electric shock current of the direct current power distribution equipment in a preset time period under the current working condition based on a first preset direct current electric shock current algorithm according to the direct current difference value of each window; And under the condition that the direct current difference value is smaller than zero, determining the direct current electric shock current of the direct current power distribution equipment in a preset time period under the current working condition according to the direct current difference value of each window based on a second preset direct current electric shock current algorithm.
3. The method according to claim 2, wherein the determining, based on the first preset dc electric shock current algorithm, the dc electric shock current of the dc power distribution device in the preset period of time under the current working condition according to the dc current difference value of each window includes: Wherein, the The method is that the ith direct current electric shock current corresponding to the ith window direct current difference value in the preset time period under the current working condition of the direct current distribution equipment, The method is that the direct current power distribution equipment is provided with an i-th window direct current difference value in a preset time period under the current working condition, Is a first preset current difference threshold.
4. The method according to claim 2, wherein the determining, based on the second preset dc electric shock current algorithm, the dc electric shock current of the dc power distribution device in the preset period of time under the current working condition according to the dc current difference value of each window includes: Wherein, the The method is that the ith direct current electric shock current corresponding to the ith window direct current difference value in the preset time period under the current working condition of the direct current distribution equipment, In order to preset the 1 st window direct current difference value in the time period under the current working condition, In order to preset the 2 nd window direct current difference value in the time period under the current working condition, In order to preset the direct current difference value of the nth window in the time period under the current working condition, For a second preset current difference threshold, n is the number of window dc current differences, The method is that the direct current power distribution equipment is provided with an i-th window direct current difference value in a preset time period under the current working condition, 。
5. The method of claim 1, wherein the step size determination method of the sliding window comprises: Wherein, the For a preset time period The step size of the sliding window at the moment, For a preset minimum value of the window step size, For a preset maximum value of the window step size, For a preset time period The step size of the sliding window at the moment, The step size is adjusted for a preset sliding window, The method is that the direct current power distribution equipment is provided with an i-th window direct current difference value in a preset time period under the current working condition, Is a preset direct current difference value.
6. The method of claim 1, wherein the determining method further comprises: And preprocessing the initial line direct current of the direct current distribution equipment in a preset time period under the current working condition to obtain a plurality of line direct currents.
7. The method of claim 6, wherein the preprocessing the initial line dc current of the dc power distribution device during the preset period of time under the current operating condition to obtain a plurality of line dc currents includes: and preprocessing the initial line direct current of the direct current distribution equipment in a preset time period under the current working condition based on a minimum mean square error filtering algorithm to obtain a plurality of line direct currents.
8. A device for determining a direct current electric shock current for a direct current distribution apparatus, comprising: A memory configured to store instructions, and A processor configured to invoke the instructions from the memory and when executing the instructions enable the method of determining a direct current electric shock current for a direct current power distribution device according to any one of claims 1 to 7.
9. A direct current power distribution apparatus, comprising: The determination device for a direct current electric shock current for a direct current power distribution apparatus according to claim 8.
10. A machine-readable storage medium having instructions stored thereon for causing a machine to perform the method of determining a dc shock current for a dc distribution device according to any one of claims 1 to 7.

Description

Method and device for determining direct current electric shock current for direct current distribution equipment Technical Field The application relates to the technical field of power grid power supply, in particular to a method and a device for determining direct current electric shock current of direct current distribution equipment. Background In recent years, with the implementation of national green energy and energy conservation and emission reduction strategies, the number of electric vehicles is increasing, and a large number of battery energy storage devices are connected to a power grid of a direct current distribution system for ensuring normal power supply of a large number of electric vehicles. At present, a direct current power distribution system generally adopts a neutral point ungrounded (IT) system or a neutral point ungrounded (IT) system which is grounded through high impedance, and the IT system has the advantages of small residual current and high safety when single-point ground faults occur. In order to ensure the safe operation of an IT system, the extraction of direct current electric shock current is important. In the prior art, under the condition that the signal characteristics of the direct current electric shock current signal and the line direct current signal are greatly different, a blind source separation algorithm is adopted to separate the signal characteristics of the line direct current signal, so that the direct current electric shock current signal can be obtained. However, under the condition that the signal characteristic difference between the direct current electric shock current signal and the line direct current signal is small, namely the signal correlation between the direct current electric shock current signal and the line direct current signal is large, the problem that the calculation reliability of the direct current electric shock current signal extracted by the blind source separation algorithm is low is caused. Disclosure of Invention The embodiment of the application aims to provide a method and a device for determining direct current electric shock current for direct current power distribution equipment, the direct current power distribution equipment and a storage medium, which are used for solving the problem of low calculation reliability of the direct current electric shock current in the prior art. In order to achieve the above object, a first aspect of the present application provides a method for determining a direct current electric shock current for a direct current power distribution apparatus, the method comprising: Obtaining direct current of a plurality of lines of direct current distribution equipment in a preset time period under the current working condition; Determining a plurality of window line direct currents corresponding to every two adjacent sliding windows in the plurality of line direct currents; Determining a plurality of difference values between the direct currents of a plurality of windows corresponding to every two adjacent sliding windows to obtain a plurality of window direct current difference values of the direct current distribution equipment in a preset time period under the current working condition; and determining the direct current electric shock current of the direct current distribution equipment in a preset time period under the current working condition according to the direct current difference values of the windows. The method comprises the steps of determining direct current electric shock current of the direct current distribution equipment in a preset time period under the current working condition according to a plurality of window direct current difference values, wherein the direct current electric shock current of the direct current distribution equipment in the preset time period under the current working condition is determined according to the window direct current difference values based on a first preset direct current electric shock current algorithm when the window direct current difference value is larger than or equal to zero, and determining direct current electric shock current of the direct current distribution equipment in the preset time period under the current working condition according to a second preset direct current electric shock current algorithm when the window direct current difference value is smaller than zero. In the embodiment of the application, based on a first preset direct current electric shock current algorithm, according to the direct current difference value of each window, the direct current electric shock current of the direct current power distribution equipment in a preset time period under the current working condition is determined, and the method comprises the following steps: Wherein, the The method is that the ith direct current electric shock current corresponding to the ith window direct current difference value in the preset time period under the