CN109188197B - Evaluation system and method for health index of high-voltage cable - Google Patents

Abstract

The application discloses an evaluation system and a method for a high-voltage cable health index, wherein the system comprises: the basic parameter analysis unit is used for comparing test data or online monitoring data of basic parameters of the high-voltage cable with a regulation standard; the inspection parameter analysis unit is used for comparing test data or online monitoring data of inspection parameters of the high-voltage cable with a rule standard; the fault probability parameter analysis unit is used for comparing test data or online monitoring data of the fault probability parameters of the high-voltage cable with a rule standard; the operation history parameter analysis unit is used for comparing the test data or the on-line monitoring data of the operation history parameters of the high-voltage cable with the regulation standard; and the comprehensive processing unit is used for obtaining the health index evaluation results of transverse comparison analysis among different high-voltage cables and longitudinal trend analysis of the same high-voltage cable. The invention has the advantages that: the health index evaluation is applied to the operation and maintenance work of the high-voltage cable, and the engineering application value is very high.

Description

An evaluation system and method for high-voltage cable health index

technical field

The present invention relates to a system and method for evaluating the health index of high-voltage cables.

Background technique

With the increasing application of high-voltage cables, some high-voltage cables have been running for many years in terms of cable operation years, and their health status management is very necessary and urgent. Due to other reasons, the breakdown of high-voltage cable lines within the design life has also led to a large increase in the number of power outages, which has brought challenges to the operational stability and power supply reliability of urban transmission and distribution lines. At present, the external environment of cable operation continues to deteriorate, coupled with poor cable construction technology and improper maintenance, which will cause hidden dangers to the health of cables that cannot be ignored. In recent years, high-voltage cable failures have occurred frequently. The above problems seriously threaten the safe operation of the power grid, but it is obviously very difficult and extremely uneconomical to replace all the old cables with a huge cost and a huge project. Therefore, it is very necessary to conduct a comprehensive evaluation and management of the health status of high-voltage cables. Effectively track the reliable operation of high-voltage cables to reduce or even eliminate vicious accidents of high-voltage cables.

CN103499777A discloses an evaluation method and system based on ultra-low frequency partial discharge detection. The method is as follows: according to the new laying or operation of the cable line, determine the power cable that needs to be evaluated for insulation performance; Disconnect and take safety measures; conduct ultra-low frequency partial discharge detection on the cable line through the ultra-low frequency cable partial discharge diagnosis and positioning system; systematically analyze the partial discharge detection results by comparing the cable path and the laying of the intermediate joint position , to effectively evaluate the insulation performance of the cable line; the system is: test power supply, filter, coupling capacitance and detection impedance, partial discharge detector. The obvious disadvantage of the prior art is that the health index of the high-voltage cable cannot be effectively evaluated comprehensively, and the operating state of the high-voltage cable cannot be managed scientifically in a targeted manner.

SUMMARY OF THE INVENTION

The purpose of the present invention is to overcome the above deficiencies and provide an evaluation system for the health index of high-voltage cables, which is simple to implement and can effectively evaluate the health index of high-voltage cables.

In order to achieve the above purpose, the technical solution adopted in the present invention is: an evaluation system for the health index of high-voltage cables, characterized in that it includes: a basic parameter analysis unit, which is used for test data or online monitoring of the basic parameters of high-voltage cables The data is compared with the regulation standard to obtain the first information data; the inspection parameter analysis unit is used to compare the test data or online monitoring data of the inspection parameter of the high-voltage cable with the regulation standard to obtain the second information data; the failure probability parameter analysis unit is used to The third information data is obtained by comparing the test data or online monitoring data of the failure probability parameters of the high-voltage cable with the regulations and standards; the operation history parameter analysis unit is used for the test data or online monitoring data and regulations of the operation history parameters of the high-voltage cable. Standard comparison, to obtain the fourth information data; the comprehensive processing unit is used for data processing according to the test data of the basic parameters, inspection parameters, failure probability parameters, operation history parameters or online monitoring data and various information data of the regulations and standards, The health index evaluation results of the horizontal comparative analysis between different high-voltage cables and the longitudinal trend analysis of the same high-voltage cable are obtained.

Another object of the present invention is to provide a method for evaluating the health index of high-voltage cables, which is characterized by comprising: a basic parameter analysis unit compares the test data or online monitoring data of the basic parameters of the high-voltage cable with the regulations and standards, and obtains the first 1. Information data; the test data or online monitoring data of the inspection parameters of the high-voltage cable by the inspection parameter analysis unit are compared with the regulations and standards to obtain the second information data; the test data or online monitoring of the failure probability parameters of the high-voltage cable by the failure probability parameter analysis unit The data is compared with the regulations and standards to obtain the third information data; the operation history parameter analysis unit compares the test data or online monitoring data of the operation history parameters of the high-voltage cable with the regulations and standards, and obtains the fourth information data; the comprehensive processing unit obtains the fourth information data according to the basic parameters , inspection parameters, failure probability parameters, test data of historical operation parameters or online monitoring data and various information data of regulations and standards, perform data processing, and obtain horizontal comparison analysis between different high-voltage cables and longitudinal trend analysis of the same high-voltage cable. Index evaluation results.

The beneficial effects of the present invention are:

The implementation is simple. The basic parameters, inspection parameters, failure probability parameters and operation history parameters of high-voltage cables are classified and scientifically evaluated and managed, so as to accurately and comprehensively obtain the evaluation conclusion of the health index. The evaluation score is less than 60 points, indicating that the cable is in If it is not in a healthy state, it needs to be repaired immediately; 61-70 points belong to a critical health state, prompting cable maintenance personnel to pay attention and analyze the reasons for the decline of the health level; 71-85 points belong to a qualified health state, and preventive tests are carried out according to the normal cycle; 85 The above points are considered to be in good health, and the period of pre-test and maintenance can be appropriately extended. A unified, comprehensive and shareable information data platform has been established; the application of health index assessment in the operation and maintenance of high-voltage cables has been realized, which has strong engineering application value.

Description of drawings

The drawings described herein are used to provide further understanding of the present application and constitute a part of the present application. The schematic embodiments and descriptions of the present application are used to explain the present application and do not constitute an improper limitation of the present application. In the attached image:

FIG. 1 is a schematic structural diagram of the evaluation system for the health index of high-voltage cables according to the present invention.

FIG. 2 is a schematic diagram of the method for evaluating the system for the health index of high-voltage cables according to the present invention.

Detailed ways

As used in the specification and claims, certain terms are used to refer to particular components. It should be understood by those skilled in the art that hardware manufacturers may refer to the same component by different nouns. The description and claims do not use the difference in name as a way to distinguish components, but use the difference in function of the components as a criterion for distinguishing. As mentioned in the entire specification and claims, "comprising" is an open-ended term, so it should be interpreted as "including but not limited to". "Approximately" means that within an acceptable error range, those skilled in the art can solve the technical problem within a certain error range, and basically achieve the technical effect. Subsequent descriptions in the specification are preferred embodiments for implementing the present application, however, the descriptions are for the purpose of illustrating the general principles of the present application and are not intended to limit the scope of the present application. The scope of protection of this application should be determined by the appended claims.

Please refer to Fig. 1, the evaluation system for the health index of high-voltage cables of the present invention includes: a basic parameter analysis unit, which is used to compare the test data or online monitoring data of the basic parameters of the high-voltage cable with the regulations and standards, and obtain the first information data ;The inspection parameter analysis unit is used to compare the test data or online monitoring data of the inspection parameters of the high-voltage cable with the regulations and standards to obtain the second information data; the failure probability parameter analysis unit is used for the test data of the failure probability parameters of the high-voltage cable. Or compare the online monitoring data with the regulations and standards, and obtain the third information data; the operation history parameter analysis unit is used to compare the test data or online monitoring data of the operation history parameters of the high-voltage cable with the regulations and standards, and obtain the fourth information data; comprehensive processing The unit is used to perform data processing according to the test data of the basic parameters, inspection parameters, failure probability parameters, operation history parameters or online monitoring data and various information data of the regulations and standards, and obtain the horizontal comparative analysis and comparison between different high-voltage cables. Health index assessment results of longitudinal trend analysis of the same high-voltage cable.

Preferably, the basic parameter analysis unit performs modeling based on fuzzy mathematical theory.

Preferably, the patrol parameter analysis unit is modeled based on artificial neural network theory.

Preferably, the failure probability parameter analysis unit is based on rough set theory for modeling.

Preferably, the basic parameter analysis unit includes a basic parameter sampling module; the patrol parameter analysis unit includes a patrol parameter sampling module; the failure probability parameter analysis unit includes a failure probability parameter sampling module; the operation history parameter analysis unit includes a Historical parameter sampling module.

Preferably, the basic parameter sampling module, the patrol parameter sampling module, the failure probability parameter sampling module and the operation history parameter sampling module are connected to the comprehensive processing unit through a communication module.

Preferably, the integrated processing unit includes a central controller, and the central controller is connected to the basic parameter sampling module, the patrol parameter sampling module, the failure probability parameter sampling module, and the operation history parameter sampling module through a communication module.

Preferably, the communication module includes a switch matrix module connected in sequence, a signal input and output device, a digital multimeter, a function generator and a spectrum analyzer.

As an extended embodiment, the high-voltage cable health index evaluation system includes a hardware device layer, a data processing and application layer; the hardware device layer provides data for the data processing and application layer.

As an extended embodiment, the hardware device layer adopts a new type of portable live detector measurement result transcription device, so that it has the function of fully electronically reading and dumping the results of the existing power distribution equipment state monitoring instrument, so as to realize the Inheritance of the instrument; based on the type, quantity, location and cost-benefit analysis of the sensors, determine the optimal layout scheme of the sensor array, and construct the state data perception sensor array for the calculation of the high-voltage cable health index; adopt a universal adapter suitable for the collection of high-voltage cable health index information , realize the standardized output of the signal; develop the automatic test software based on the health index state information collection terminal to complete the automatic test and transmission of the health index state information.

As an extended embodiment, the high-voltage cable health index evaluation data platform adopts an object-oriented method, based on a database management system (Database Management System, DBMS), establishes a sound data platform, realizes data stratification, classification, and hierarchical management, and supports query , calling and tabulation and other information use methods, and can realize information exchange and sharing with the existing database of the power grid.

The present invention also provides an evaluation method for the health index of high-voltage cables, which includes: a basic parameter analysis unit compares the test data or online monitoring data of the basic parameters of the high-voltage cable with regulations and standards, and obtains first information data; a patrol parameter analysis unit Compare the test data or online monitoring data of the inspection parameters of the high-voltage cable with the regulations and standards to obtain the second information data; the failure probability parameter analysis unit compares the test data or online monitoring data of the failure probability parameters of the high-voltage cables with the regulations and standards to obtain the first Three information data; the operation history parameter analysis unit compares the test data or online monitoring data of the operation history parameters of the high-voltage cable with the regulations and standards, and obtains the fourth information data; the comprehensive processing unit obtains the fourth information data according to the basic parameters, inspection parameters, failure probability parameters, The test data of historical parameters or online monitoring data and various information data of regulations and standards are processed to obtain the health index evaluation results of the horizontal comparative analysis between different high-voltage cables and the longitudinal trend analysis of the same high-voltage cable.

Preferably, the method of the present invention includes: performing data collection to obtain basic parameters, inspection parameters, failure probability parameters, test data or online monitoring data of historical operation parameters related to the state of the high-voltage cable; the evaluation score is less than 60 points, indicating that the cable is If it is in a non-healthy state, it needs to be repaired immediately; 61-70 points belong to a critical health state, prompting cable maintenance personnel to pay attention and analyze the reasons for the decline of the health level; 71-85 points belong to a qualified health state, and preventive tests are carried out according to the normal cycle; A score of 85 or more is considered to be in good health, and the period of pre-test and maintenance can be appropriately extended.

As an extended example, determine the scoring function of the high-voltage cable health index:

N---Number of subcomponents

FRi---Subcomponent failure rate

PSCi---local score of subcomponent

SCMAX---Maximum score

SCmin---minimum score.

As an extended embodiment, determine the membership function of the rating level: Substitute each state quantity into the corresponding single-item state quantity scoring function for scoring, and then substitute the obtained score into the membership function of each rating level.

As an extended embodiment, each index weight coefficient K of basic parameters, inspection parameters, failure probability parameters, and operation history parameters is calculated, and the evaluation method and maintenance strategy of high-voltage cables based on four factors are studied. At the same time, the present invention will study the proportion of scores. , so that high-voltage cables can be classified and scientifically comprehensively evaluated and managed, and the evaluation is carried out according to the following score weight evaluation block diagram. Combined with the different weights of the four factors, the score evaluation conclusion can be obtained. The coefficient K represents the comparison between test data or online monitoring data and regulations and standards. Corresponding coefficient, the evaluation conclusion can be used for the lateral comparative analysis between different cables and the longitudinal trend analysis of the same cable.

As an extended example, the base state scores are obtained by training the database.

As an extended embodiment, the manufacturing and life indices of high-voltage cables are collected. According to the life equation, there is a life index n value, and n≥9 is required internationally.

As an extended example, the parameters of high-voltage cable laying and bending radius are collected. my country's national standard GB50168-92, "Electrical Installation Engineering, Cable Line Construction and Acceptance Specifications" stipulates the electrical laying radius: single-core 20D, multi-core 15D . In the current numerous cable bidding, some requirements meet the bending radius of 10D, but when the 275KV cross-linked cable is laid at a temperature of 105 ℃, the conductor is compressed and the insulation is deformed by 10% (2.5mm). It is also said that if the overload temperature reaches 130 °C, the general bending radius is not acceptable, and it should be greater than 30D. This test was published in the International Large Grid Report in 1984. For this reason, our country's 220KV communication cable stipulates that the minimum bending radius is 25D. Therefore, the bending radius is also a factor affecting the life of the cable, which cannot be ignored.

As an extended example, collect the operation and overload parameters of high-voltage cables. Overload refers to the operation when the temperature exceeds 90°C, and there are short-circuit, short-term and emergency overloads, which are affected by temperature; overvoltage refers to exceeding the maximum operating voltage; Voltage, there is lightning overvoltage, is the effect of voltage. Overload and overvoltage will affect the cable life. DC tests have been shown to be detrimental to cross-linked cables, mainly due to space charge effects, especially for medium and high voltage cables. Due to the high absolute value of the test voltage, it is more likely to damage the cross-linked insulation and space charge, and it is easy to cause insulation breakdown during the DC discharge process, or during the subsequent high-voltage no-load process.

As an extended embodiment, through the detection of partial discharge and dielectric loss of the cable, the operating state parameters of the cable are collected, so as to predict the life of the cable. Under the action of high voltage, the internal insulation of high-voltage electrical equipment such as cables is discharged. This kind of discharge only exists in the local position of the insulation, and will not immediately form the entire insulation penetration breakdown or flashover, so it is called partial discharge. The amount of partial discharge is very weak and cannot be detected by people's intuition, such as hearing with eyes and ears, and only a highly sensitive partial discharge measuring instrument can detect it.

As an extended embodiment, the detection of partial discharge is based on various phenomena generated by partial discharge, and the state of partial discharge is characterized by a physical quantity that can express the phenomenon. When partial discharge occurs inside insulating equipment, many physical and chemical phenomena occur. Some are electrical, such as electric pulse, increased dielectric loss, electromagnetic wave radiation, etc.; some are non-electric, such as ultrasonic, light, heat, etc. The corresponding detection methods can be divided into two categories: electrical measurement method and non-electrical measurement method , such as pulse current method, high frequency detection method, ultra-high frequency detection method, ultrasonic detection method, optical measurement method, chemical detection method, infrared detection method, transient ground voltage and other detection methods. Among them, the pulse current method, the high frequency detection method, the ultra-high frequency detection method, the ultrasonic detection method and the transient ground voltage are put into practical application.

As an extended embodiment, the partial discharge test system detects the ultra-high frequency, ultrasonic, radio frequency, and high frequency partial discharge signals of high-voltage cables in real time; can make pre-judgment of high-voltage cable defects according to the characteristic values of partial discharge; provides a more intuitive spectrum The analysis function provides an important analysis basis for PD pattern recognition; during PD detection, it can effectively identify the interference of mobile communication and digital TV frequency bands to PD signals; it has the function of noise interference pulse suppression, which can effectively filter out background noise; , with the monitoring software, the position of the monitored partial discharge can be locked, so as to effectively eliminate the fault.

As an extended embodiment, the high-frequency current transformer installed on the grounding cable in the grounding box divides the sensed current signal into three channels and sends them to the partial discharge signal frequency measurement circuit, the partial discharge signal strength measurement circuit and the low-frequency grounding current respectively. Signal measurement circuit; the intelligent monitoring terminal divides the input signal of the partial discharge signal frequency measurement circuit into high frequency partial discharge signal and instantaneous narrow pulse partial discharge signal according to the duration; at the same time, the partial discharge strength measurement circuit is triggered to measure the signal strength, and the high frequency partial discharge signal is measured. The frequency and intensity of the partial discharge signal are time-weighted to obtain the defect level of the high-voltage cable; the instantaneous narrow pulse partial discharge signal is counted according to the time period; for those exceeding the preset defect level and the pulse count set value, it is used as the alarm status information; Connect the sensed low-frequency current signal to the low-frequency signal interface of the intelligent monitoring terminal with a transmission cable, obtain current data after AD conversion, and judge the state of direct grounding according to the preset value; externally installed gas sensor, temperature and humidity sensor and water level The signal of the alarm is converted by the intelligent monitoring terminal to determine whether the set gas concentration limit, humidity limit and water level alarm effective value are exceeded. If the limit is exceeded, the alarm status information is output; the optical fiber temperature measurement installed in the middle joint of the cable The sensor transmits the signal to the single-chip microcomputer for AD conversion through photoelectric conversion, and the obtained temperature value is compared with the temperature limit value of the intermediate joint. If the limit value is exceeded, an alarm state is output; the ultrasonic probe installed outside the explosion-proof box of the intermediate joint detects the partial discharge signal of the intermediate joint. After pre-amplification and logarithmic detection circuit, it is converted into a pulse signal and transmitted to the single-chip microcomputer, and compared with the partial discharge limit value of the intermediate joint, if the limit is exceeded, the alarm state is output; all data and alarm state information are transmitted by the wireless GPRS module to the remote monitoring server; The monitoring computer connected to the remote monitoring server can refresh these data and status information through the web page.

The advantages of the present invention are:

The implementation is simple. The basic parameters, inspection parameters, failure probability parameters and operation history parameters of high-voltage cables are classified and scientifically evaluated and managed, so as to accurately and comprehensively obtain the evaluation conclusion of the health index. The evaluation score is less than 60 points, indicating that the cable is in If it is not in a healthy state, it needs to be repaired immediately; 61-70 points belong to a critical health state, prompting cable maintenance personnel to pay attention and analyze the reasons for the decline of the health level; 71-85 points belong to a qualified health state, and preventive tests are carried out according to the normal cycle; 85 The above points are considered to be in good health, and the period of pre-test and maintenance can be appropriately extended. A unified, comprehensive and shareable information data platform has been established; the application of health index assessment in the operation and maintenance of high-voltage cables has been realized, which has strong engineering application value.

The above description shows and describes several preferred embodiments of the present application, but as mentioned above, it should be understood that the present application is not limited to the form disclosed herein, and should not be regarded as excluding other embodiments, but can be used in various and other combinations, modifications and environments, and can be modified within the contemplation of the application described herein, using the above teachings or skill or knowledge in the relevant art. However, modifications and changes made by those skilled in the art do not depart from the spirit and scope of the present application, and should all fall within the protection scope of the appended claims of the present application.

Claims (6)

1. an evaluation system for high-voltage cable health index, is characterized in that, comprises: The basic parameter analysis unit is used to compare the test data or online monitoring data of the basic parameters of the high-voltage cable with the regulations and standards, and obtain the first information data; The inspection parameter analysis unit is used to compare the test data or online monitoring data of the inspection parameters of the high-voltage cable with the regulations and standards, and obtain the second information data; The failure probability parameter analysis unit is used to compare the test data or online monitoring data of the failure probability parameter of the high-voltage cable with the regulations and standards, and obtain the third information data; The operation history parameter analysis unit is used to compare the test data or online monitoring data of the operation history parameters of the high-voltage cable with the regulations and standards, and obtain the fourth information data; The comprehensive processing unit is used to process data according to the test data of the basic parameters, inspection parameters, failure probability parameters, operation history parameters or online monitoring data and various information data of the regulations and standards, and obtain the horizontal comparison between different high-voltage cables Analysis and health index evaluation results of longitudinal trend analysis of the same high-voltage cable; the integrated processing unit performs data processing according to the algorithm:

Among them, N---the number of subcomponents, FRi---the failure rate of the subcomponents, PSCi---the local score of the subcomponents, SCMAX---the maximum score, SCmin---the minimum score; the basic parameter analysis The unit is modeled based on fuzzy mathematics theory; the patrol parameter analysis unit is modeled based on artificial neural network theory; the failure probability parameter analysis unit is modeled based on rough set theory. 2. The evaluation system for high-voltage cable health index according to claim 1, characterized in that, The basic parameter analysis unit includes a basic parameter sampling module; The patrol parameter analysis unit includes a patrol parameter sampling module; The failure probability parameter analysis unit includes a failure probability parameter sampling module; The operation history parameter analysis unit includes an operation history parameter sampling module. 3. The evaluation system for high-voltage cable health index according to claim 2, wherein the basic parameter sampling module, the patrol parameter sampling module, the failure probability parameter sampling module and the operation history parameter sampling module communicate with each other through the communication module. The integrated processing unit is connected. 4. The evaluation system for the health index of high-voltage cables according to claim 3, wherein the comprehensive processing unit comprises a central controller, and the central controller patrols the basic parameter sampling module through a communication module. The parameter sampling module, the failure probability parameter sampling module, and the running history parameter sampling module are connected. 5. The evaluation system for high-voltage cable health index according to claim 4, wherein the communication module comprises a switch matrix module connected in sequence, a signal input and output device, a digital multimeter, a function generator and a spectrum analysis instrument. 6. An evaluation method for high-voltage cable health index, characterized in that, comprising: The basic parameter analysis unit compares the test data or online monitoring data of the basic parameters of the high-voltage cable with the regulations and standards, and obtains the first information data; The inspection parameter analysis unit compares the test data or online monitoring data of the inspection parameters of the high-voltage cable with the regulations and standards, and obtains the second information data; The failure probability parameter analysis unit compares the test data or online monitoring data of the failure probability parameter of the high-voltage cable with the regulations and standards, and obtains the third information data; The operation history parameter analysis unit compares the test data or online monitoring data of the operation history parameters of the high-voltage cable with the regulations and standards, and obtains the fourth information data; The comprehensive processing unit performs data processing according to the basic parameters, inspection parameters, failure probability parameters, test data of operation history parameters or online monitoring data and various information data of the regulations and standards, and performs data processing according to the algorithm:

, and obtain the health index evaluation results of the horizontal comparative analysis between different high-voltage cables and the longitudinal trend analysis of the same high-voltage cable.

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