CN-122006335-A - Online purifying device and method for insulating oil in high-voltage cable terminal

CN122006335ACN 122006335 ACN122006335 ACN 122006335ACN-122006335-A

Abstract

The invention discloses an online purifying device and method for insulating oil in a high-voltage cable terminal, and relates to the technical field of power grids, wherein the online purifying device comprises an intelligent monitoring unit, a circulating flow unit, a purifying unit and an insulating oil supplementing unit; the intelligent monitoring unit is used for monitoring oil quality and oil quantity of insulating oil in a cable terminal in real time, the circulating flow unit is used for promoting the insulating oil to circulate between the cable terminal and the purifying unit, the purifying unit is used for purifying the insulating oil which circulates, the insulating oil supplementing unit is used for supplementing the insulating oil into a pipeline of the circulating flow unit and the cable terminal, and when the intelligent monitoring unit detects that the oil quantity in the cable terminal is smaller than a set threshold value, the insulating oil in the insulating oil supplementing unit is conveyed into the cable terminal through the circulating flow unit. The invention can clean the internal insulating oil on line without power failure, which not only saves time and labor, but also reduces maintenance cost.

Inventors

LIU YANZHUO
SHAO TIANYANG
ZHANG XIAOMING
WANG XIAOBO
SONG LUYU
MA NENGZHU
YAN XIFENG
JIA CHAO
FANG JU
Yi Yalin
Cheng Jueming
PAN HAIPING
LI ZHIWEN

Assignees

长园电力技术有限公司

Dates

Publication Date: 20260512
Application Date: 20260416

Claims (10)

1. The online purifying device for the insulating oil in the high-voltage cable terminal is characterized by comprising an intelligent monitoring unit, a circulating flow unit, a purifying unit and an insulating oil supplementing unit; the intelligent monitoring unit comprises an oil quality monitoring module for monitoring oil quality in real time and an oil quality monitoring module for monitoring oil quality of insulating oil in a cable terminal; the circulating flow unit is used for promoting the insulating oil to circulate between the cable terminal and the purifying unit, and the purifying unit is used for purifying the circulating flowing insulating oil; The insulating oil supplementing unit is used for supplementing insulating oil into the pipeline and the cable terminal of the circulating flow unit; and when the intelligent monitoring unit detects that the oil quantity in the cable terminal is smaller than a set threshold value, the insulating oil in the insulating oil supplementing unit is conveyed into the cable terminal through the circulating flow unit until the intelligent monitoring unit detects that the oil quantity in the cable terminal is larger than or equal to the set threshold value.
2. The on-line purification device for insulating oil inside a high-voltage cable terminal according to claim 1, wherein the oil quality monitoring module is arranged on the outer side of the cable terminal and comprises a humidity sensor, a particle sensor and a gas detection module, and the oil quality monitoring module comprises a pressure sensor arranged on the top of an inner cavity of the cable terminal and used for detecting the pressure of the inner cavity of the cable terminal to reflect the oil quality of the insulating oil.
3. The on-line purification device for insulating oil inside a high-voltage cable terminal according to claim 1, wherein the purification unit comprises a micro-filtration unit for removing particulate impurities in the insulating oil flowing in a circulation manner and an adsorption unit for removing moisture and dissolved gas in the insulating oil flowing in a circulation manner.
4. The on-line purification device for insulating oil inside a high-voltage cable terminal according to claim 3, wherein the adsorption unit comprises a housing and a multi-layer composite filter assembly arranged in the housing, and the multi-layer composite filter assembly comprises a front filter screen, a middle filter core and a rear filter core which are sequentially arranged along the flowing direction of the insulating oil.
5. The on-line purification device for insulating oil in a high-voltage cable terminal according to claim 4, wherein the front filter screen is a stainless steel metal sintering net, the middle filter core is a high-precision glass fiber or high-polymer filter core, and the rear filter core is a homogeneous membrane filter core.
6. The on-line purification apparatus for insulating oil inside a high voltage cable terminal according to claim 3, wherein the adsorption unit comprises a molecular sieve material and activated alumina.
7. The online purification device for insulating oil inside a high-voltage cable terminal according to claim 3, wherein the circulating flow unit comprises a circulating pump and a circulating flow pipeline assembly, the circulating flow pipeline assembly comprises an oil outlet circulating pipeline, an intermediate flow pipeline and an oil inlet circulating pipeline, one end of the oil outlet circulating pipeline is communicated with an outlet of the cable terminal, the other end of the oil outlet circulating pipeline is communicated with an inlet end of the circulating pump, the intermediate flow pipeline comprises a first intermediate flow pipeline, a second intermediate flow pipeline and a third intermediate flow pipeline, one end of the first intermediate flow pipeline, one end of the second intermediate flow pipeline and one end of the third intermediate flow pipeline are respectively communicated with an outlet end of the circulating pump, and the other ends of the first intermediate flow pipeline, the second intermediate flow pipeline and the third intermediate flow pipeline are respectively communicated with one end of the oil inlet circulating pipeline; the oil outlet circulation pipeline is provided with an oil outlet electromagnetic valve, and the first middle flow pipeline, the second middle flow pipeline and the third middle flow pipeline are respectively provided with a first middle electromagnetic valve, a second middle electromagnetic valve and a third middle electromagnetic valve.
8. The on-line purification device for insulating oil inside a high-voltage cable terminal according to claim 7, wherein the insulating oil supplementing unit comprises an insulating oil supplementing container and an insulating oil supplementing pipeline, one end of the insulating oil supplementing pipeline is communicated with an outlet of the insulating oil supplementing container, the other end of the insulating oil supplementing pipeline is communicated with an inlet end of a circulating pump, and an insulating oil supplementing electromagnetic valve is arranged on the insulating oil supplementing pipeline.
9. The purifying method applied to the online purifying device for the insulating oil in the high-voltage cable terminal as claimed in claim 8 is characterized by comprising a plurality of working modes, namely: In the working mode, the oil quantity monitoring module is in a working state, the capacity of insulating oil in the cable terminal is detected in real time, and all electromagnetic valves are kept in a closed state; When the oil quantity monitoring module detects that the oil quantity in the cable terminal is smaller than a set threshold value, opening an insulating oil supplementing electromagnetic valve and a first intermediate electromagnetic valve, keeping other electromagnetic valves in a closed state, starting a circulating pump to pump out insulating oil of an insulating oil supplementing container, and supplementing new insulating oil into the cable terminal through an insulating oil supplementing pipeline and a first intermediate flow pipeline until the oil quantity monitoring module detects that the oil quantity in the cable terminal is larger than or equal to the set threshold value; In the working mode, according to a preset periodic monitoring time point, an insulating oil supplementing electromagnetic valve and a third intermediate electromagnetic valve are opened, other electromagnetic valves are kept in a closed state, a circulating pump is started to pump insulating oil of an insulating oil supplementing container, the insulating oil flows into a cable terminal through an insulating oil supplementing pipeline and a third intermediate flow pipeline until the oil quantity monitoring module detects that the oil quantity in the cable terminal is increased, the insulating oil is full of the third intermediate flow pipeline; When the oil quality monitoring module detects that the oil quality parameter of the insulating oil at the cable terminal exceeds the standard, the insulating oil supplementing electromagnetic valve and the second intermediate electromagnetic valve are opened, other electromagnetic valves are kept in a closed state, the circulating pump is started to pump out the insulating oil of the insulating oil supplementing container, the insulating oil flows into the cable terminal through the insulating oil supplementing pipeline and the second intermediate flow pipeline until the oil quality monitoring module detects that the oil quantity in the cable terminal is increased, the insulating oil is full of the second intermediate flow pipeline, the oil outlet electromagnetic valve and the second intermediate electromagnetic valve are formally started to be purified, other electromagnetic valves are kept in a closed state, the circulating pump is started to pump out the insulating oil in the cable terminal, the insulating oil is conveyed into the micro-filtration unit and the adsorption unit of the purifying unit through the second intermediate flow pipeline, and the micro-filtration unit and the adsorption unit are used for purifying the insulating oil in real time.
10. The method for purifying insulation oil in a high-voltage cable terminal according to claim 9, wherein the oil mass monitoring module detects the capacity of insulation oil in the cable terminal in real time in the purifying operation mode, and when the oil mass monitoring module detects that the oil mass in the cable terminal is smaller than a set threshold, the insulation oil supplementing solenoid valve is opened again in a state that the oil outlet solenoid valve and the second intermediate solenoid valve are opened, the circulation pump simultaneously pumps out insulation oil in the insulation oil supplementing container, and the insulation oil is supplemented into the cable terminal through the insulation oil supplementing pipeline and the second intermediate flow pipeline until the oil mass monitoring module detects that the oil mass in the cable terminal is greater than or equal to the set threshold.

Description

Online purifying device and method for insulating oil in high-voltage cable terminal Technical Field The invention relates to a high-voltage cable terminal technology, in particular to an online purifying device and method for insulating oil in a high-voltage cable terminal. Background The high-voltage cable terminal is a key component in the power transmission system, and insulating oil filled in the high-voltage cable terminal carries important insulating and heat-dissipating functions. The quality of the insulating oil is directly related to the safe and stable operation of the cable termination and even the whole cable line. In the long-term operation process, the insulating oil is affected by various factors to be gradually deteriorated, on one hand, external moisture can invade through a weak sealing link to increase the moisture content in the oil, and on the other hand, faults such as aging, partial discharge or overheating of internal materials can generate tiny particle impurities and characteristic dissolved gases such as hydrogen, methane and acetylene. These contaminants can significantly reduce the breakdown voltage and dielectric loss tangent of the insulating oil, exacerbate the aging of the insulating material, and eventually can lead to terminal insulation failure, causing serious electrical accidents. At present, the maintenance of the insulating oil in the cable terminal mainly depends on two modes, namely, the periodic replacement of all the insulating oil and the off-line purification treatment of the insulating oil extraction and the reinjection of the insulating oil. The two traditional methods have obvious defects that firstly, the two traditional methods are required to be carried out under the condition of power failure of a cable, the operation flow is complex, time and labor are consumed, power supply interruption is caused, and huge economic and social costs are brought, secondly, the off-line treatment belongs to periodic maintenance, sudden rapid degradation of insulating oil cannot be dealt with in real time, a maintenance blind area exists, and moreover, in the oil pumping and oiling processes, if the treatment is improper, air, moisture or new particle pollution is extremely easy to be introduced, and secondary air risk is brought. Disclosure of Invention The invention aims to overcome the problems, and provides the online purifying device for the insulating oil in the high-voltage cable terminal, which can online purify the insulating oil in the high-voltage cable terminal without power failure, thereby saving time and labor and greatly reducing maintenance cost. The invention further aims to provide an online purifying method for the insulating oil in the high-voltage cable terminal. The aim of the invention is achieved by the following technical scheme: an online purifying device for insulating oil in a high-voltage cable terminal comprises an intelligent monitoring unit, a circulating flow unit, a purifying unit and an insulating oil supplementing unit; The intelligent monitoring unit is used for monitoring oil quality and the oil quality of insulating oil in the cable terminal in real time, the circulating flow unit is used for promoting the insulating oil to circulate between the cable terminal and the purifying unit, and the purifying unit is used for purifying the insulating oil which circulates; The insulating oil supplementing unit is used for supplementing insulating oil into the pipeline and the cable terminal of the circulating flow unit; and when the intelligent monitoring unit detects that the oil quantity in the cable terminal is smaller than a set threshold value, the insulating oil in the insulating oil supplementing unit is conveyed into the cable terminal through the circulating flow unit until the intelligent monitoring unit detects that the oil quantity in the cable terminal is larger than or equal to the set threshold value. According to the preferred scheme, the intelligent monitoring unit comprises an oil quality monitoring module and an oil quantity monitoring module, wherein the oil quality monitoring module is arranged on the outer side of a cable terminal and comprises a humidity sensor, a particle sensor and a gas detection module, and the oil quantity monitoring module comprises a pressure sensor which is arranged on the top of an inner cavity of the cable terminal and used for detecting the pressure of the inner cavity of the cable terminal to reflect the oil quantity of insulating oil. Through the structure, the synchronous and real-time online monitoring of the key quality parameters (moisture, particles and fault gas) of the insulating oil and the oil quantity state (indirectly and accurately reflected through pressure) inside the terminal is realized, an accurate criterion is provided for intelligent start and stop of the purifying process, more importantly, the pressure fluctuation caused by oil quantity change inside the terminal can b