CN-121679263-B - Partial discharge diagnosis method, equipment and medium for direct-current transformer

CN121679263BCN 121679263 BCN121679263 BCN 121679263BCN-121679263-B

Abstract

The embodiment of the invention provides a partial discharge diagnosis method, equipment and medium of a direct current transformer, wherein the method comprises the steps of detecting a direct current partial discharge position according to a first partial discharge sensor and a second partial discharge sensor on a mobile detection model under the condition that the first partial discharge sensor detects a direct current partial discharge signal; and determining the defect type of the direct current partial discharge position according to the gas detection data and the direct current partial discharge signal. The method has the advantages that the partial discharge sensor arranged on the direct-current transformer and the partial discharge sensor on the mobile robot are used for cooperatively positioning the direct-current partial discharge position, so that the method can adapt to various discharge conditions, reduces installation cost and detection cost, and can be used for rapidly diagnosing the defect type of the direct-current partial discharge position through the gas detection data and the direct-current partial discharge signal of the direct-current partial discharge position, and has high defect diagnosis efficiency and low detection cost.

Inventors

YI XIAOBO
YANG KAI
WU JIANMING
LIN HAIJUN
LIN HAIRONG
Miao Chusheng
WEN SHENGYONG
HUANG HAOJIAN
DONG QIXIN
LIAO WENGAO

Assignees

珠海市伊特高科技有限公司

Dates

Publication Date: 20260512
Application Date: 20260206

Claims (10)

1. The utility model provides a partial discharge diagnosis method of direct current transformer, characterized by is applied to the power network management system, the power network management system is provided with the digital twin model of direct current transformer and the mobile detection model that mobile robot corresponds, all be provided with a plurality of different types partial discharge sensor on direct current transformer and the mobile robot, the method includes: Under the condition that a first partial discharge sensor on the digital twin model detects a direct current partial discharge signal, detecting a direct current partial discharge position according to the first partial discharge sensor and a second partial discharge sensor on the mobile detection model, wherein the first partial discharge sensor and the second partial discharge sensor both represent the partial discharge sensor; the method specifically comprises the steps of constructing a first plane on a first median vertical line of any two first partial discharge sensors with equal first receiving time when at least two first partial discharge sensors receive the direct current partial discharge signals on the digital twin model are equal, constructing a first plane between the second partial discharge sensors and the first partial discharge sensors when the first receiving time of any two first partial discharge sensors on the digital twin model are not equal, constructing a second plane in a second direction through the second partial discharge sensors and/or the first partial discharge sensors positioned at opposite positions, constructing a third plane in a third direction, and determining the direct current position according to the first plane, the second plane and the third plane, wherein the first direction, the second direction and the third direction are perpendicular; The construction of the first plane between the second partial discharge sensor and the first partial discharge sensor comprises the steps of configuring any one of the first partial discharge sensors as a first target sensor and acquiring a first target position of the first target sensor on the direct current transformer, controlling the mobile robot to move along the first direction passing through the first target position through the movement detection model and acquiring a real-time position of the mobile robot, acquiring a second receiving time of the second partial discharge sensor for receiving the direct current partial discharge signal at the real-time position, configuring the real-time position as a second target position when the second receiving time is equal to the first receiving time of the first target sensor, and constructing the first plane on a second middleline of the first target position and the second target position; Acquiring gas detection data of the direct current partial discharge position, wherein the gas detection data indicates gas types and the content of each gas; And determining the defect type of the direct current partial discharge position according to the gas detection data, the pulse current information, the ultra-high frequency spectrum information and the ultrasonic information indicated by the direct current partial discharge signal.
2. The partial discharge diagnosis method of a dc transformer according to claim 1, characterized in that the second plane is constructed in a second direction by the second partial discharge sensor and/or the first partial discharge sensor being located in a relative position: When the receiving time of the direct current partial discharge signals received by the two first partial discharge sensors is equal on the first perpendicular bisector or the second perpendicular bisector, configuring the two first partial discharge sensors with equal receiving time as a second target sensor; constructing the second plane on a third midwifery line between two of the second target sensors; When there is no first partial discharge sensor on the first perpendicular bisector or the second perpendicular bisector, the receiving time of the direct current partial discharge signal received by the two first partial discharge sensors is equal, and at least one first partial discharge sensor is present, configuring the first partial discharge sensor, any one of which is located on the first perpendicular bisector or the second perpendicular bisector, as a third target sensor; Moving the mobile robot on the first or second perpendicular bisector, and configuring a position on the mobile robot, which corresponds to when the receiving time of the second partial discharge sensor is equal to the receiving time of the third target sensor, as a third target position, wherein the third target sensor is not located at the third target position; Constructing the second plane on a fourth midwifery line between the third target location and the third target sensor; Moving the mobile robot on the first perpendicular bisector or the second perpendicular bisector when the first partial discharge sensor is not present on the first perpendicular bisector or the second perpendicular bisector, and configuring two relative positions where the receiving time of the second partial discharge sensor is equal as a fourth target position; The second plane is constructed on a fifth midwifery line between two of the fourth target positions.
3. The partial discharge diagnosis method of a dc transformer according to claim 2, wherein the constructing a third plane in a third direction includes: When the receiving time of the direct current partial discharge signals received by the two first partial discharge sensors is equal on the third perpendicular bisector, the fourth perpendicular bisector or the fifth perpendicular bisector, the two first partial discharge sensors with equal receiving time are configured as a fourth target sensor; constructing the third plane on a sixth midwifery line between two of the fourth target sensors; when there are no two first partial discharge sensors on the third perpendicular bisector, the fourth perpendicular bisector, or the fifth perpendicular bisector, the receiving times of the direct current partial discharge signals received by the first partial discharge sensors are equal, and there is at least one first partial discharge sensor, configuring the first partial discharge sensor, any of which is located on the third perpendicular bisector, the fourth perpendicular bisector, or the fifth perpendicular bisector, as a fifth target sensor; Moving the mobile robot on the third perpendicular bisector, the fourth perpendicular bisector, or the fifth perpendicular bisector, and configuring a position on the mobile robot corresponding to when a reception time of the second partial discharge sensor is equal to a reception time of the fifth target sensor as a fifth target position, the fifth target sensor not being located at the fifth target position; constructing the third plane on a seventh midvertical line between the fifth target location and the fifth target sensor; Moving the mobile robot on the third perpendicular bisector, the fourth perpendicular bisector, or the fifth perpendicular bisector, when the first partial discharge sensor is not present on the third perpendicular bisector, the fourth perpendicular bisector, or the fifth perpendicular bisector, and configuring two relative positions where the reception times of the second partial discharge sensor are equal as a sixth target position; The third plane is constructed on an eighth midwifery line between the two sixth target positions.
4. The partial discharge diagnosis method of a dc transformer according to claim 1, wherein the determining the dc partial discharge position from the first plane, the second plane, and the third plane includes: configuring an intersecting straight line of the first plane and the second plane as a target straight line; Configuring an intersection point of the target straight line and the third plane as a target point; and configuring the spatial position of the target point as the direct current partial discharge position.
5. The partial discharge diagnosis method of a dc transformer according to claim 1, wherein the determining the defect type of the dc partial discharge location based on the gas detection data and pulse current information, ultra-high frequency spectrum information, and ultrasonic information indicated by the dc partial discharge signal includes: Configuring a discharge type of the direct current partial discharge position as corona discharge under the conditions that the apparent discharge quantity represented by the pulse current information is smaller than a first discharge quantity threshold, the variance of the pulse amplitude is smaller than a first variance threshold, and the pulse repetition rate is larger than a first repetition rate threshold, the ultra-high frequency spectrum information represents that the frequency spectrum is located in a first frequency range, the frequency spectrum pulse width is smaller than a first pulse width threshold, the frequency spectrum pulse amplitude is smaller than a first pulse amplitude threshold, and the ultrasonic information represents that the sound wave amplitude is smaller than a first sound wave threshold, the sound wave frequency is located in a first sound wave frequency range and the signal duration is smaller than a first signal time; In the case where the discharge type is corona discharge: If the gas detection data represent that the content of hydrogen is 200-500 mu L/L, the content ratio of methane to organic gas is 60-80%, the content ratio of hydrogen to organic gas is 40-60%, and the content ratio of ethane to organic gas is 10-20%, the defect type of the direct current partial discharge position is configured as winding end oil gap electric field distortion; If the gas detection data show that the content of hydrogen is 100-300 mu L/L, the content ratio of methane to organic gas is 50-60%, the content ratio of hydrogen to organic gas is 50-70%, and the content ratio of ethane to organic gas is less than 10%, the defect type of the direct current partial discharge position is configured as poor grounding of a sleeve end screen; And if the gas detection data show that the content of hydrogen is 150-400 mu L/L, the content ratio of methane to organic gas is 70-90%, the content ratio of hydrogen to organic gas is 30-50%, and the content of organic gas is 100-200 mu L/L, configuring the defect type of the direct current partial discharge position as metal burrs on the surface of the lead.
6. The partial discharge diagnosis method of a dc transformer according to claim 5, further comprising: Configuring a discharge type of the direct current partial discharge position as a creeping discharge in a case that the apparent discharge amount represented by the pulse current information is between a first discharge amount threshold and a second discharge amount threshold, the variance of the pulse amplitude is larger than a second variance threshold, the pulse repetition rate is between a second repetition rate threshold and a first repetition rate threshold, the extra-high frequency spectrum information represents that the frequency spectrum is in a second frequency range, the frequency spectrum pulse width is between the first pulse width threshold and the second pulse width threshold, the frequency spectrum comprises energy peaks of a plurality of frequency bands, and the ultrasonic information represents that the sound wave amplitude is between a first sound wave threshold and a second ultrasonic wave threshold, the sound wave frequency is respectively in a first sound wave frequency range and a second sound wave frequency range, and the signal duration is between a first signal time and a second signal time; in the case where the discharge type is creeping discharge: If the gas detection data represent that the content of hydrogen is 400-800 mu L/L, the content ratio of methane to organic gas is 30-40%, the content ratio of ethylene to organic gas is 35-45%, the content of carbon monoxide is 200-300 mu L/L, and the content ratio of carbon dioxide to carbon monoxide is 5-8, the defect type of the direct current partial discharge position is configured as winding insulation dirt; If the gas detection data show that the content of hydrogen is 300-500 mu L/L, the content ratio of methane to organic gas is 40-50%, the content ratio of ethylene to organic gas is 25-35%, the content of carbon monoxide is 100-200 mu L/L, and the content ratio of carbon dioxide to carbon monoxide is 8-10, configuring the defect type of the direct current partial discharge position as an air gap on the inner wall of the sleeve; And if the gas detection data show that the content of hydrogen is 350-600 mu L/L, the content ratio of methane to organic gas is 35-45%, the content ratio of ethylene to organic gas is 30-40%, the content of carbon monoxide is 150-250 mu L/L and the content ratio of ethane to organic gas is 10-15%, configuring the defect type of the direct current partial discharge position as the damage of the lead outer insulating layer.
7. The partial discharge diagnosis method of a dc transformer according to claim 5, further comprising: Configuring the discharge type of the direct current partial discharge position as spark discharge when the apparent discharge quantity represented by the pulse current information is between a second discharge quantity threshold and a third discharge quantity threshold, the pulse amplitude is in clustered distribution, the pulse repetition rate is between a third repetition rate threshold and a second repetition rate threshold, the extra-high frequency spectrum information represents that the frequency spectrum is in a third frequency range, the frequency spectrum pulse width is between the second pulse width threshold and the third pulse width threshold, the frequency spectrum pulse amplitude is larger than the second pulse amplitude threshold, and the ultrasonic information represents that the acoustic wave amplitude is between a second acoustic wave threshold and a third ultrasonic wave threshold, the acoustic wave frequency is in a third acoustic wave frequency range, and the signal duration is between a second signal time and a third signal time; In the case where the discharge type is spark discharge: If the gas detection data represent that the content of hydrogen is 1000-1500 mu L/L, the content ratio of ethylene to organic gas is 40-50%, the content ratio of acetylene to organic gas is 5-8%, the content of carbon monoxide is 500-600 mu L/L, and the content ratio of carbon dioxide to carbon monoxide is 3-4, configuring the defect type of the direct current partial discharge position as winding insulation breakage; If the gas detection data represent that the content of hydrogen is 800-1200 mu L/L, the content ratio of methane to organic gas is 40-45%, the content ratio of ethylene to organic gas is 35-40%, the content ratio of acetylene to organic gas is 3-5%, and the content of carbon monoxide is 300-400 mu L/L, the defect type of the direct current partial discharge position is configured as iron core insulation breakage; And if the gas detection data represent that the content of hydrogen is 900-1300 mu L/L, the content ratio of methane to organic gas is 30-35%, the content ratio of ethylene to organic gas is 35-45%, the content ratio of acetylene to organic gas is 4-7%, and the content of organic gas is 400-600 mu L/L, configuring the defect type of the direct current partial discharge position as that metal chips exist in transformer oil.
8. The partial discharge diagnosis method of a dc transformer according to claim 5, further comprising: When the apparent discharge quantity represented by the pulse current information is larger than a third discharge quantity threshold, pulse amplitude values are distributed in a spike shape, and pulse repetition rate is smaller than a third repetition rate threshold, the extra-high frequency spectrum information represents that a frequency spectrum is located in a fourth frequency range, the frequency spectrum pulse width is larger than the third pulse width threshold, the frequency spectrum pulse amplitude variance is smaller than a third variance threshold, and the ultrasonic information represents that the acoustic wave amplitude value is larger than a third ultrasonic threshold, the acoustic wave frequency is located in a fourth acoustic frequency range, and the signal duration time is longer than a third signal time, the discharge type of the direct current partial discharge position is configured to be arc discharge; in the case where the discharge type is arc discharge: If the gas detection data represent that the content of hydrogen is 2000-5000 mu L/L, the content ratio of acetylene to organic gas is 30-50%, the content of carbon monoxide is 1000-2000 mu L/L, and the content ratio of carbon dioxide to carbon monoxide is 1-2, configuring the defect type of the direct current partial discharge position as winding insulation breakdown; If the gas detection data represent that the content of hydrogen is 1500-3000 mu L/L, the content ratio of acetylene to organic gas is 40-60%, the content of carbon monoxide is 600-1200 mu L/L, and the content ratio of carbon dioxide to carbon monoxide is 2-3, the defect type of the direct current partial discharge position is configured as lead joint damage; If the gas detection data represent that the content of hydrogen is 1800-3500 mu L/L, the content ratio of acetylene to organic gas is 35-55%, the content ratio of ethane to organic gas is 5-10%, the content of carbon monoxide is 700-1500 mu L/L, and the content ratio of carbon dioxide to carbon monoxide is 1.5-2.5, the defect type of the direct current partial discharge position is configured as poor contact of the tap changer.
9. A partial discharge diagnostic device for a dc transformer, comprising a memory, a processor and a computer program stored on the memory and executable on the processor, said processor implementing the method for partial discharge diagnosis of a dc transformer according to any one of claims 1-8 when said computer program is executed by said processor.
10. A computer storage medium storing computer executable instructions for performing the partial discharge diagnosis method of a dc transformer according to any one of claims 1 to 8.

Description

Partial discharge diagnosis method, equipment and medium for direct-current transformer Technical Field The invention relates to the technical field of power detection, in particular to a partial discharge diagnosis method, equipment and medium of a direct current transformer. Background The DC transformer is power electronic equipment for DC voltage conversion, and conversion of different DC voltage classes is realized through high-frequency chopping, transformer isolation and high-frequency rectification technology. Partial discharge is an electrical phenomenon in a dc transformer that can indicate not only the insulation state of the dc transformer, but often also a precursor to insulation failure of the dc transformer. Therefore, the method for detecting and diagnosing the fault type in time at the initial stage of the fault of the direct-current transformer has remarkable significance for guaranteeing safe and reliable operation of the direct-current transformer. However, the prior art is to detect the partial discharge of the ac transformer, and it is difficult to meet the requirement of the partial discharge diagnosis of the dc transformer. Disclosure of Invention The following is a summary of the subject matter described in detail herein. This summary is not intended to limit the scope of the claims. The embodiment of the invention mainly aims to provide a partial discharge diagnosis method, equipment and medium for a direct current transformer, which can accurately diagnose the partial discharge of the direct current transformer. In a first aspect, an embodiment of the present invention provides a partial discharge diagnosis method of a dc transformer, which is applied to a power grid management system, where the power grid management system is provided with a digital twin model of the dc transformer and a movement detection model corresponding to a mobile robot, and the dc transformer and the mobile robot are both provided with a plurality of different types of partial discharge sensors, and the method includes: under the condition that a first partial discharge sensor on the digital twin model detects a direct current partial discharge signal, detecting a direct current partial discharge position according to the first partial discharge sensor and a second partial discharge sensor on the mobile detection model, wherein the first partial discharge sensor and the second partial discharge sensor both represent the partial discharge sensor; Acquiring gas detection data of the direct current partial discharge position, wherein the gas detection data indicates gas types and the content of each gas; And determining the defect type of the direct current partial discharge position according to the gas detection data, the pulse current information, the ultra-high frequency spectrum information and the ultrasonic information indicated by the direct current partial discharge signal. In some alternative embodiments, the detecting the direct current partial discharge position according to the first partial discharge sensor and the second partial discharge sensor on the movement detection model includes: Under the condition that the first receiving time of the direct current partial discharge signals received by at least two first partial discharge sensors on the digital twin model is equal, constructing a first plane on a first middle vertical line of any two first partial discharge sensors with equal first receiving time, wherein the first plane is positioned in a first direction; Under the condition that the first receiving time of the two first partial discharge sensors is not equal on the digital twin model, constructing a first plane between the second partial discharge sensor and the first partial discharge sensor; Constructing a second plane in a second direction and constructing a third plane in a third direction through the second partial discharge sensor and/or the first partial discharge sensor which are positioned at opposite positions, wherein the first direction, the second direction and the third direction are perpendicular to each other; and determining the direct current partial discharge position according to the first plane, the second plane and the third plane. In some alternative embodiments, the constructing the first plane between the second partial discharge sensor and the first partial discharge sensor includes: configuring any one of the first partial discharge sensors as a first target sensor, and acquiring a first target position of the first target sensor on the direct current transformer; Controlling the mobile robot to move along the first direction passing through the first target position through the movement detection model, and acquiring a real-time position of the mobile robot; Acquiring a second receiving time of the direct current partial discharge signal received by the second partial discharge sensor at the real-time position; Configuring the real-time location as a seco