CN-122021020-A - Digital twinning-based subway electric hidden trouble investigation and intelligent fire-fighting linkage method

CN122021020ACN 122021020 ACN122021020 ACN 122021020ACN-122021020-A

Abstract

The invention relates to the technical field of digital twinning and discloses a digital twinning-based subway electric hidden trouble shooting and intelligent fire-fighting linkage method, which comprises the steps of firstly constructing a digital twinning model of an electric assembly, establishing a synchronous time sequence taking a driving interval as a reference, inputting environment and voltage data acquired in real time into the model to calculate the drift rate of an insulating surface water film under the drive of an electric field; and finally, comparing the calculated dynamic effective creepage distance with the minimum safety distance regulated by an insulation fit standard, and automatically judging hidden danger and generating an operation and maintenance work order when the calculated dynamic effective creepage distance is lower than the safety standard. The early warning and automatic handling of the electrical insulation fault under the subway damp-heat environment are realized through mechanism modeling.

Inventors

SUN SHU
SUN XIANGPENG
LIU XIAOSHUAI
LIU HUI
LU KUO
FU YIQIAO
WANG YING
LIU YEMING
GUO LEI
HAO XIAOPENG
HAN JINWEI

Assignees

天津保泰安全技术服务有限公司

Dates

Publication Date: 20260512
Application Date: 20260130

Claims (7)

1. Digital twinning-based subway electric hidden trouble investigation and intelligent fire-fighting linkage method is characterized by comprising the following steps: the method comprises the steps of constructing a digital twin model comprising the nominal creepage distance of an electric component and the distribution characteristic of a surface electric field, establishing a driving period synchronous time sequence taking a driving interval as a reference according to a train operation time table, inputting synchronously acquired station environment parameters and component operation voltage data into the digital twin model, calculating the thickness of a water film formed by condensation of an insulating surface and the driving drift rate of the water film under the action of electric field force, calculating the accumulated drift displacement of the water film along the electric field direction in one complete period of the driving period synchronous time sequence, calculating a periodic water film migration ratio index based on the accumulated drift displacement and the nominal creepage distance, carrying out exponential decay correction on the nominal creepage distance by utilizing the periodic water film migration ratio index, calculating to obtain a dynamic effective creepage distance reflecting the current insulating capability, comparing the dynamic effective creepage distance with a minimum safety creepage distance preset according to an insulating fit standard, judging that electric fire hazards exist and automatically generating an operation work sheet comprising a fault component positioning and insulating treatment instruction when the dynamic effective creepage distance is smaller than the minimum safety creepage distance.
2. The digital twinning-based subway electric hidden trouble shooting and intelligent fire fighting linkage method according to claim 1, wherein constructing a digital twinning model containing nominal creepage distance and surface electric field distribution characteristics of an electric component comprises: the method comprises the steps of recording nominal creepage distance and surface characteristic length obtained through building information models and product specifications for each controlled electric component, obtaining geometric electric field proportionality coefficient determined by component geometric shape through off-line finite element electric field simulation calculation, and constructing a real-time mapping relation between insulation surface tangential electric field amplitude and component ground effective value voltage, wherein the insulation surface tangential electric field amplitude is equal to the geometric electric field proportionality coefficient multiplied by the component ground effective value voltage acquired in real time.
3. The digital twinning-based subway electric hidden trouble shooting and intelligent fire control linkage method according to claim 1, wherein the step of establishing a driving period synchronous time sequence taking a driving interval as a reference according to a train operation time table comprises the following steps: The method comprises the steps of obtaining continuous train passing time stamps from train signal system records, carrying out arithmetic average on the last preset number of running interval time, calculating to obtain an average running period, calculating normalized real-time synchronous phases based on the time difference between the current time and the last train passing time stamp and combining the average running period, wherein the real-time synchronous phases are equal to twice the circumference ratio and multiplied by the ratio of the time difference to the average running period.
4. The digital twin-based subway electric hidden trouble shooting and intelligent fire fighting linkage method according to claim 2, wherein synchronously acquired station environment parameters and component operation voltage data are input into the digital twin model, and the thickness of a water film formed by condensation on an insulating surface and the driving drift rate of the water film electric field of the water film under the action of electric field force are calculated, comprising: The method comprises the steps of utilizing synchronously collected air temperature, relative humidity and insulating surface temperature to calculate air vapor density and insulating surface saturated vapor density, utilizing synchronously collected wind speed near the surface and surface characteristic length in a digital twin model to calculate Reynolds number and Xie Wude number so as to further determine a convection mass transfer coefficient, calculating a net mass transfer flux according to the convection mass transfer coefficient and a difference value between the air vapor density and the insulating surface saturated vapor density, utilizing a smooth non-negative projection function comprising logarithmic and exponential operation, updating equivalent water film thickness at the last moment according to the net mass transfer flux and the water density to obtain equivalent water film thickness at the current moment, and calculating to obtain a water film electric field driving drift rate based on a vacuum dielectric constant, dynamic viscosity of water, the equivalent water film thickness and square of an insulating surface tangential electric field amplitude calculated by the digital twin model.
5. The digital twinning-based subway electric hidden trouble shooting and intelligent fire control linkage method according to claim 4, wherein calculating the accumulated drift displacement of the water film along the electric field direction in one complete period of the driving period synchronous time sequence and calculating the periodic water film migration duty ratio index based on the accumulated drift displacement and the nominal creepage distance comprises: Performing time integration or discrete accumulation on the water film electric field driving drift rate in a complete driving period of the driving period synchronous time sequence to obtain accumulated drift displacement; dividing the accumulated drift displacement by the nominal creepage distance to obtain the periodic water film migration duty ratio index.
6. The digital twinning-based subway electric hidden trouble shooting and intelligent fire fighting linkage method according to claim 5, wherein the step of performing exponential decay correction on the nominal creepage distance by using the periodic water film migration duty ratio index, and calculating to obtain a dynamic effective creepage distance reflecting the current insulation capability comprises the following steps: And calculating a natural index function value after the periodic water film migration duty ratio index takes a negative value, and multiplying the calculation result by the nominal creepage distance to obtain the dynamic effective creepage distance, wherein the natural index function is used for representing the nonlinear attenuation characteristic of the effective insulation path under the water film migration effect.
7. The digital twinning-based subway electric hidden trouble shooting and intelligent fire fighting linkage method according to claim 6, wherein comparing the dynamic effective creepage distance with a minimum safe creepage distance preset according to an insulation fit standard, when the dynamic effective creepage distance is smaller than the minimum safe creepage distance, determining that there is an electric fire hidden trouble and automatically generating an operation and maintenance work order including a fault component positioning and insulation handling instruction, comprises: The method comprises the steps of searching an insulation matching standard database according to voltage of an effective value of a component to the ground, environmental pollution level and insulating material group, determining the minimum safe creepage distance, extracting the minimum value of the dynamic effective creepage distance in the latest preset number of driving cycles, and generating an operation and maintenance work order if the minimum value is smaller than the minimum safe creepage distance, wherein the content of the operation and maintenance work order comprises component numbers and positions of alarm objects, numerical comparison evidence of the minimum safe creepage distance of a triggering work order and the dynamic effective creepage distance, and an action sequence comprising power failure isolation, appearance inspection and insulation cleaning.

Description

Digital twinning-based subway electric hidden trouble investigation and intelligent fire-fighting linkage method Technical Field The invention relates to the technical field of digital twinning, in particular to a subway electric hidden trouble shooting and intelligent fire-fighting linkage method based on digital twinning. Background Urban rail transit systems are used as the traffic aorta of modern cities, and underground stations and section tunnels thereof are in relatively closed and environmentally complex underground spaces for a long time. In order to maintain the normal running of the train and the safety and comfort of passengers, a large number of high-voltage and low-voltage electric equipment such as a ring control cabinet, a contact net supporting insulator, a cable connector, a power illumination distribution box and the like are deployed in the subway. Because the underground environment has the characteristics of high humidity, easy condensation and dust aggregation, and the severe piston wind effect caused by the high-frequency entrance and exit of the train, the surface of the insulating medium of the electrical equipment is subjected to composite stress caused by air flow impact, temperature alternation and wet and hot corrosion for a long time. The stability of the electrical insulation performance is directly related to the reliability of a subway power supply system, and once insulation breakdown or surface flashover occurs, serious electrical fire accidents are easily caused, so that the train is stopped. In order to monitor the operation state of electrical equipment and prevent fire, existing subway operation and maintenance systems generally employ an environment and equipment monitoring system (BAS) or a fire automatic alarm system (FAS) for passive monitoring. The main technical means comprises: 1. Environmental data are collected in a station hall, a platform and an equipment room through temperature and humidity sensors, when relative humidity or temperature exceeds a preset fixed value (for example, humidity is more than 85% or temperature is more than 80 ℃), an alarm is triggered, 2, a key cable connector is subjected to periodic temperature scanning through an infrared thermal imaging technology or a temperature sensing optical fiber, 3, a residual current transformer is used for monitoring real-time leakage current of a power supply loop, and when the leakage current amplitude breaks through a safety threshold, a power supply is cut off. Part of advanced schemes attempt to utilize big data statistics to analyze historical fault rules and make regular manual inspection and cleaning plans so as to maintain the insulation level of equipment. However, the above prior art has significant technical limitations in facing intermittent strong disturbance conditions of the subway. Firstly, the static threshold method cannot adapt to a dynamic environment, the periodic operation of a subway train can cause severe transient fluctuation of the air pressure, the air speed and the humidity of a local microenvironment, the traditional fixed threshold monitoring always regards the high-frequency fluctuation as noise to carry out smooth processing, so that the instantaneous high risk caused by the superposition of environmental stress at a specific driving moment is omitted, secondly, the existing method only independently monitors the scalar quantity of the humidity or the heat without the mechanism analysis of multivariable field coupling, ignores the moisture of an insulating surface under the action of a strong electric field, but can migrate and spread, the pure high humidity is not equivalent to insulation failure, the dynamic process of communicating a creepage path under the driving of the electric field cannot be revealed, the false report and the danger without the existence of the alarm are caused, finally, the early warning has obvious hysteresis, the existing current monitoring or the thermal imaging usually gives an alarm after the irreversible damage (such as carbonization channel formation) or the obvious short circuit occurs, at the moment, the optimal preventive maintenance window is always missed in an early stage, and the insulation degradation process cannot be realized. Disclosure of Invention The invention provides a digital twinning-based subway electric hidden trouble shooting and intelligent fire-fighting linkage method, which solves the technical problems in the background technology. The invention provides a digital twinning-based subway electric hidden trouble shooting and intelligent fire-fighting linkage method, which comprises the following steps: the method comprises the steps of constructing a digital twin model comprising the nominal creepage distance of an electric component and the distribution characteristic of a surface electric field, establishing a driving period synchronous time sequence taking a driving interval as a reference according to a train