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ObjectivesTo enhance the intelligent management of substation equipment maintenance, timely identify and mitigate the risks of failures caused by device overheating, and ensure the safe and stable operation of the power grid, the temperature situation awareness and auxiliary decision-making scheme of substation equipment were proposed.MethodsThe research was carried out from four aspects: the perception layer, the understanding layer, the prediction layer, and the auxiliary decision-making layer. In the perception layer, the K-nearest neighbor (KNN) classification algorithm was used to analyze the correlation of multi-class temperature data. In the understanding layer, a BP neural network was employed to construct a historical data transmission model to address missing historical data issues. In the prediction layer, a temperature prediction model combining autoregressive integrated moving average (ARIMA) and support vector machine (SVM) was designed to handle nonlinear data and noise. In the auxiliary decision-making layer, the grey relational analysis was applied to analyze the relationship between equipment temperature changes and fault risks.ResultsThe verification results of numerical examples based on the proposed scheme show that the scheme realizes the effective perception of the future temperature variation trends of the equipment and provides a basis for the identification of equipment defects.ConclusionsThrough multi-dimensional and deep-level temperature data analysis, the proposed scheme reveals the potential correlation between equipment temperature and fault risk, realizes the prediction of the operational trend of substation equipment, and provides a reference for the optimization of operational mode and the formulation of equipment maintenance plan.

Real-time monitoring of temperature changes in substation equipment is crucial for preventing failures and ensuring a stable power supply. Currently, temperature monitoring of substation equipment primarily relies on manual infrared thermometry, which has limitations such as strong operational dependence, susceptibility to interference, and difficulty in detecting internal faults. The luminous intensity ratio (LIR) is a stable optical parameter unaffected by factors such as spectral loss and environmental influences, making it suitable for temperature detection. The multi-emission characteristics of rare-earth-doped upconversion (UC) materials are highly compatible with LIR technology, demonstrating their potential in high-precision temperature monitoring. Here we introduces a non-contact temperature monitoring method for substation equipment based on NaErF4@ NaYF4 core-shell UC materials and LIR technique. Experiments show that the method has high accuracy and sensitivity within temperature range of 25 °C to 225 °C, with a sensitivity as high as 35 x 10-3 °C-1, effectively monitoring temperature changes both inside and outside the equipment. This provides a new technical solution for temperature monitoring of substation equipment. [ABSTRACT FROM AUTHOR]

Copyright of Fly Ash Comprehensive Utilization is the property of Hebei Fly Ash Comprehensive Utilization Magazine Co., Ltd. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Power Generation Technology is the property of Power Generation Technology Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Objective With the increasing power supply load required by metro, the operation of oil-immersed equipment such as wet-type transformers under overload conditions is extremely prone to fire, posing a threat to the safety of ceiling structure. To avoid or reduce the possibility of transformer fires, it is necessary to investigate the smoke movement patterns and the variation characteristics of ceiling temperature in main transformer room during fire. Method Taking the 110 kV Qichuan Substation of Jinan Rail Transit Line 3 as example, through theoretical analysis and numerical simulation, considering the comprehensive effects of ventilation conditions, fire heat release rate, and fire source height, the temperature characteristics of smoke below the ceiling in main transformer room during fire are investigated. Result & Conclusion When mechanical ventilation is activated, the organization of indoor airflow will affect the distribution of smoke temperature below the ceiling. Wind replenishment causes the fire plume to deflect, leading to the maximum temperature rise point shifting towards exhaust vents, with the maximum temperature rise slightly lower than when mechanical ventilation is closed. The dimensionless maximum ceiling temperature rise can be divided into two regions: when the flame does not impinge on the ceiling, it exhibits a linear relationship between the dimensionless maximum temperature rise and the ratio of Q2/5 and (hef-h0) (where Q is the fire heat release rate, hef is the distance from fire source surface to the ceiling, h0 is the virtual point source height); when the fire flame impinges on the ceiling, the dimensionless maximum temperature rise is a constant, and a prediction model for the dimensionless maximum temperature rise of the ceiling is proposed. Based on simulation data, prediction models for temperature decrease of ceiling jets driven by weak and strong fire plumes are proposed.

Copyright of Urban Mass Transit is the property of Urban Mass Transit Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

As a branch of quantum information technology， quantum communication technologies hold significant value for enhancing communication security in future substations. This paper delves into the current development status and engineering feasibility of various quantum communication technologies. A cryptographic comparison between traditional asymmetric key encryption systems and quantum key distribution （QKD） encryption systems is presented. The technical characteristics of three communication architectures and the generalizability of their engineering applications are analyzed. The potential application scenarios of quantum communication technologies in substations are outlined， along with suggestions for addressing challenges encountered in their application.

Copyright of Journal of Beijing University of Technology is the property of Journal of Beijing University of Technology, Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Zhejiang Electric Power is the property of Zhejiang Electric Power Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Railway Construction Technology is the property of Railway Construction Technology Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Purposes Owing to the varietry of electrical equipment and the complex connection between them in transformer station, there are many common problems includeng relatively limited location and picture contrast of equipment, insufficient target images and markers in practical applications, and inaccurate electrical equipment image segmentation brought by the traditional way. In this paper, CNN (Convolutional Neural Network) is combined with Transformer to form a new model for segmentation of electrical equipment, and a new SE-Transfomer (Substation Equipment Transformer) network based on codec structure is proposed. Methods To obtain the local context information, the coder extracts the spatial feature map by using CNN at first. Meanwhile, the feature map is carefully modified with multi-scale feature inputs for global feature modeling. The decoder extracts global deep features using Transformer and performs stepwise up-sampling to predict the detailed segmentation map. SE-Transfomer is extensively experimented on the dataset of Liangjiazhuang Transformer Station in Shanxi province, and its longitudinal results of Dice, Recall, Specificity, and RMSE (Root Mean Square Error) are 89.31%, 90.52%, 89.62%, and 11.32, respectively. Findings The results indicate that SE-Transfomer obtains comparable or higher results than previous state-of-the-art segmentation methods on the scanning of electrical equipment in the transformer station.

[Introduction] With the rapid development of power electronic equipment and artificial intelligence and other high-tech, DC (Direct Current) system has been popularized and applied in substations. The grounding fault of the substation DC system has become an important factor affecting the safe and stable operation of the substation. [Method] Firstly, the DC system of the substation was introduced, and its components, typical types of DC ground faults and their adverse effects were analyzed. Then, the principle of five common DC ground fault finding strategies was emphasized. [Result] Based on their respective research status and application scenarios, the advantages and disadvantages of various finding strategy are compared and analyzed. [Conclusion] Combined with the existing problems and technical development trends, the future research directions of DC grounding fault detection at home and abroad are prospected from the perspectives of accurate fault location, complex fault identification, finding accuracy and the improvement of the endurance of portable insulation detection device.

Copyright of Journal of Guangxi Normal University - Natural Science Edition is the property of Gai Kan Bian Wei Hui and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In order to improve the ability of remote monitoring and intelligent prevention and control of the operating environment and public safety status of intelligent substation equipment, a substation intelligent auxiliary control system based on three-dimensional model was proposed. According to the equipment selection and layout requirements of substation intelligent auxiliary control system, the database was developed and designed. The 3D model was used to share the 3D design results of substation intelligent auxiliary control system. The 3D design of substation intelligent auxiliary control system was completed through 3D design model verification and infrared dual-authentication 3D modeling, and the 3D modeling algorithm was optimized to obtain the 3D modeling output results. The simulation results show that the system has good output power stability, strong anti-interference ability, high efficiency of closed-loop management and processing of operation and maintenance, which is conducive to improving the remote monitoring and intelligent prevention and control ability of substation equipment. [ABSTRACT FROM AUTHOR]

Aiming at the problems of low efficiency, low level of intelligent operation and low level of data informatization application encountered in the current substation equipment test operation, a mobile laboratory platform based on grid cloud data management was developed. This paper focused on the theoretical process of the result judgment of the expert analysis system embedded in the mobile laboratory platform. Combined with the practical application cases of transformer differential protection after operation, according to the test results of low-voltage short-circuit impedance method, capacitance method, frequency response characteristic method, transformation ratio and direct resistance test, the reliability of the embedded expert analysis system to analyze the winding deformation caused by the short circuit impact of the transformer was illustrated. Finally, according to the results of the dismantling inspection after returning to the factory, the validity of the platform in the field application was further verified.

Copyright of Railway Construction Technology is the property of Railway Construction Technology Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Southern Energy Construction is the property of Southern Energy Construction Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

When the current method is used to draw the graph model of the new energy substation, the graph configuration software is not used, which leads to the long time spent in generating the graph model and the low quality factor of the graph model. An integrated generation method of new energy substation graphics and models based on graphic configuration software was proposed. The graphic configuration software was designed by graphic attribute automatic drawing module, primitive model library building module, equipment primitive graphic information saving and expanding module, system specification description(SSD) reading and analyzing module, SSD model and equipment primitive association module and primary equipment graphic drawing module. The inner model graphics and outer model graphics of substation were designed in the graphic configuration software, and the optimization objective function is established. particle swarm optimization (PSO) was used to solve the optimization objective function. The experimental results show that the proposed method is more efficient, of better quality and of higher practical applicability. [ABSTRACT FROM AUTHOR]

In order to realize real-time and multi-dimensional control of substation risk early warning, a substation risk early warning and control system based on edge computing is designed. The sensing layer collects the operation data of substation equipment through the Internet of Things equipment, and transmits the data to the edge layer through the communication between edge equipment and external equipment. After receiving data, edge layer parses the data through the communication protocol to complete data consistency, and packages cloud services downstream data sending to the cloud computing layer. The layer uses cloud computing to compute and analyze substation equipment data and transmit it to the application layer. The application layer adopts support vector machine (SVM) algorithm to establish a risk early warning mechanism, divide the risk data attribute, and obtain warning value. Based on this, the risk situation corresponding to the early warning value is predicted by the logistic regression risk prediction model, and the probability of failure is obtained to complete the substation risk warning. Meanwhile, the early warning results are presented on the visual interface, and the corresponding risk warning is controlled and controlled by the control channel. The test results show that the communication jitter results of the system are all below 15 ms, which can realize the calculation of risk probability, obtain the number of various risk warnings of the substation, have good work energy efficiency, and realize the multi-dimensional risk warning and control of the substation.

To carry out research on the particle size distribution, micro -morphology, and composition characteristics of combustible combustion smoke particles, and comprehensively understand the smoke information of fires. Methods The cable outer sheath, rubber tires, wire insulation layer, insulating cardboard, transformer oil, and fire residue oil at the combustion site of the substation fire were collected. Through combustion simulation experiments, use a particle matter classification sampler to collect the smoke particles released by combustion and analyze the particle size distribution characteristics of different smoke particles and their distribution in different deposition sites of the human respiratory tract. By comparing the scanning electron microscope images of different particle sizes of smoke dust, the micro-morphology and elemental composition of different particle sizes were surveyed. Results Based on ion chromatography analysis, Cl- emission factor was 0.089 2-1.207 2 滋g/g, accounting for 57.3%-67.9% of water-soluble ions, and there were differences in its particle size distribution characteristics between solid and liquid combustibles. Conclusions The smoke particles released by different combustibles were mainly particles with a diameter less than 0.25 滋m, and there were differences in Cl - emission factors. These differences could be used as the basis for evaluating the source of smoke dust and respiratory exposure assessment of personnel at fire scenes. [ABSTRACT FROM AUTHOR]

Copyright of Power Generation Technology is the property of Power Generation Technology Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Aiming at the safety and stability issues of the proposed substation in Pingdingshan City, Henan Province, the substation was taken as the research object. Based on the basic geological conditions and mining conditions of the substation, the goaf was detected comprehensively the transient electromagnetic method and drilling detection. By analyzing the longitudinal profile of apparent resistivity obtained by transient electromagnetic detection and the relationship curve between formation depth and apparent resistivity, it could be seen that there are low resistance anomalies in some depths. The horizontal range of the low-resistance anomaly area was further determined by analyzing the horizontal profile of apparent resistivity. The relationship between the drilling depth and the core rate obtained by drilling detection could accurately determine the depth range where the rock formation is relatively broken and has a small amount of water leakage. It could be determined that the abnormal area of the mined-out area is located in the west of the proposed area according to the comprehensive analysis of the two detection results, and there are uncertain factors in the safety and stability of the mined-out area underlying the substation, and effective mined-out area governance measures must be taken to ensure the safe and stable operation of the substation.

With the construction of the national smart grid, there are more and more sensors in substations, and due to the large area of substations, how to unify the management, monitoring, and maintenance of substation devices has become an urgent need. Wireless mesh network has the ability of self-organization of network and self-healing, and can independently control each node to meet the above requirements. In this paper, ESP32 was used as the hardware node module, and its own WIFI module was used to configure and network the Mesh network. The connection and communication between the sensors and ESP32, the data transfer from lower computer, and the data analysis and database saving operations from upper computer were realized. In addition, a complete Mesh network framework was established. The test results show that the system has a simple and clear structure, quick deployment, easy maintenance, which basically meets the implementation of the Internet of things (IoT) in a substation environment.

Copyright of Journal of Test & Measurement Technology is the property of Publishing Center of North University of China and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Ground Improvement is the property of Journal of Ground Improvement Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Electric Drive is the property of Electric Drive Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Terminal equipment represented by inspection robots is widely used in substations. In the future, 5th-Generation (5G) mobile terminals will be more and more used in substations with the fast development of 5G technology. The performance of the communication system is closely related to the wireless channel. Therefore, it is very important to study the 5G communication channel characteristics of the mobile terminal in the substation. Aiming at the characteristics of the communication channel of 5G mobile terminals in the Three-Dimension (3D) scattering environment of substations, based on the multiple input multiple output technology, the article proposes to use geometric analysis to establish a 3D channel model, and derive the time autocorrelation function and spatial cross correlation function of the channel. Based on the 5G frequency band, the autocorrelation and cross-correlation characteristics of the wireless channel are simulated and analyzed. The influence of the Rice factor of different sizes on the wireless channel characteristics is also studied. The above simulation results show the availability of 5G terminals in substations, and broaden the research on mobile terminals using 5G communication technology in substation scenarios.

Copyright of Railway Standard Design is the property of Railway Standard Design Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

[Introduction] In order to enhance the self-rescule ability under fire conditions of the 110 kV powder substation, a fire-fighting strategy is proposed based on the ubiquitous electric power internet of things (UEP-IoT) technology. [Method] The framework of its four layers, including perception layer, network layer, platform layer and application layer was presented. The methodology on how to arrange the fire detecors, fire-extinguishing installations as well as smart management platform were explained. A detailed scheme on how to bulid the fire control system based on UEP-IoT of the 110 kV outdoor substation was given as an example. [Result] By combing the wireless sensor technology and the central management platform, the system can realize multi-level alert and self-rescue for the protected substation. [Conclusion] The results from this study will provide a valuable sample for future substation fire-fighting system design.

Copyright of Electric Power Automation Equipment / Dianli Zidonghua Shebei is the property of Electric Power Automation Equipment Press and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

For achieving the requirement of real-time video monitoring which is located in the circuit cut-over operating point of the substation of the National Grid Nanjing Branch,China Telecom Nanjing Branch developed a new real-time video monitoring system which was based on internet of things technology and 4G wireless transmission network,by creating a smart pipeline based on 4G VPDN (virtual private dial-up network).The new system has solved the problem that the cable can not be used due to the frequent changing of the circuit cut-over operating points of the substation.

Copyright of Study on Optical Communications / Guangtongxin Yanjiu is the property of Study on Optical Communications Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Acta Materiae Compositae Sinica is the property of Acta Materiea Compositae Sinica Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Mine Automation is the property of Industry & Mine Automation Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In order to prevent the occurrence that people enter the unsafe area by mistake in the substation, a high-precision patrol robot system combining UWB with machine vision is designed. This system requires personnel to wear UWB positioning tags and patrol designated routes of robots to mark sudden increase of unsafe areas and upload them to the background to achieve safety alarm protection for workers in dangerous areas. By setting an early warning area on the periphery of the unsafe area, workers will be alerted as soon as they enter the area. After testing, the rate of system failure to report (should alarm but not report) is 0.15%, and the rate of system failure to report (should not alarm but alarm) is 0.36%. [ABSTRACT FROM AUTHOR]

As smart grid is proposed in the national development strategy, the development of the intelligent substations is developing rapidly, which puts forward higher requests for the comprehensive quality of power system staff. This paper introduces a three-dimensional simulation system of substation used for teaching and training. Firstly, this paper briefly describes its software and hardware environment, introduces its function for teaching and training examination, which contains two-dimension and three-dimensional simulation. Secondly, by using three cases such as the substation busbar earth-fault simulation, substation inspection simulation and actual operation process simulation, it explains the operation flow of this system, as well as the three-dimensional characteristics and application advantages, aiming at providing training for operators and students, to improve their practical skills. This system has good compatibility, authenticity and scalability, can meet the training requirements of the power industry staff in the development of intelligent substation at the present stage, and has a good practical application effect [ABSTRACT FROM AUTHOR]

Substation is an indispensable part of the current power system, affecting people' s production and life all the time. The teaching effect of the substation system staff is related to the safe, stable and reliable operation of the entire substation system. In view of the shortcomings of the traditional substation simulation teaching system, which is complex, expensive and dangerous, a 10 kV substation in Chaozhou is used as a prototype to develop a teaching system by combining VR technology. 3DS MAX is used for substation equipment. model establishment and optimization, the C# language is used to write the corresponding script in Unity3 D software to complete the development of 10 kV substation teaching simulation system. The results show that the 10 kV substation teaching simulation system can effectively reduce the cost of the teaching system, and it is safe, easy to use, and vivid in teaching content, which can quickly improve the technical level of the substation system staff. [ABSTRACT FROM AUTHOR]

The high speed railway substation is the core component of the electrified railway,Its professional skill can he improved through training system. In view of the current status of the training system for the high speed railway substation, three levels of training systems have been built, i. e. , holistic system, special system and autonomous learning system. The characteristics and application of various training systems are compared. Practice can be carried out on real equipment, and can he simulated. Training projects can lie developed independently from the basic learning to the difficulties, and then to the overall improvement. The process of improving skill can be realized. [ABSTRACT FROM AUTHOR]

From the perspective of regulation and operation，an accident of secondary reverse charging of bus potential transformer is analyzed in dealing with the 220 kV bus voltage imbalance in a substation． In the process of reversing the bus，the secondary reverse charging of the bus potential transformer is caused by the inadequate switching of auxiliary contact of the spacing element bus． The problems existing in the field operation and dispatching disposal process are summarized，and some suggestions are put forward to provide a reference for the regulating and controlling operators to deal with such accidents． [ABSTRACT FROM AUTHOR]

In order to assess the influence of electromagnetic interference in the substation of the electric power communication system,frequency measurement method was adopted to obtain the data of 2.4 GHz electromagnetic wave path loss of the substation of 110 kV and 220 kV in a certain city.By using the method of minimum mean square error (MMSE) and cumulative sum (CUSUM) to estimate the parameters of path loss model such as path loss index and the standard deviation,the path loss model was set up according to measured data,respectively.The simulation results show that the gap between estimation results and the measured values is not big.In addition,a ZigBee simulation system was constructed to simulate the relationship of bit error rate (BER) varies with distance in two cases of the signal to noise ratio (SNR) at 5 dB and 10 dB respectively.A research basis for short distance wireless communication devices decorated in the substation environment was provided.

Copyright of Guangdong Architecture Civil Engineering is the property of Guangdong Architecture Civil Engineering Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In view of problem of misoperation of protection device caused by DC system grounding fault which often appears in substations, the concept of capacitive reactive power of DC system was proposed, and an optimized scheme of centralized power supply of DC system was designed applying optimization method of capacitive reactive power. The optimization scheme reduces DC line-to-ground capacitive character, and achieves the purpose of reducing reactive power by optimizing circuit trail on the basis of meeting supply reliability. It solves the misoperation problem of protection device and improves operating efficiency of DC system. Finally, the effect of the reactive power optimization scheme was evaluated to verify its reliability, security and economical efficiency.

By means of deduction of zero-sequence current expressions when single-phase grounding fault occurs in single substation mode and multi-substation mode of coal mine resonant grounding system, polarity relationship between transient pulse of fault line and normal line, and relationships among amplitude or width of transient pulse, grounding resistance, shunt capacitance and fault time were analyzed, and corresponding expressions were given. Polarity of transient pulse of fault line is opposite to the ones of normal lines, and amplitude of the transient pulse of fault line is the largest among all lines. The amplitude of transient pulse at the fault time is inversely proportional to grounding resistance and proportional to sin of angle of fault phase. All the normal lines have the same width of transient pulse, which is smaller than the one of the fault line, and the width of transient pulse is proportional to the grounding resistance. The Matlab/Simulink simulation proves correctness of above theoretical conclusions.

In order to study the impact of soil on the grounding grid corrosion in substation, the author expounded the reasons of grounding grid corrosion in substation and the basic types and analyzed the impact of bulk density, salt content, water content, resistivity, microorganism, pH value and other factors on grounding grid corrosion in soil. The corrosion prevention measures were proposed by cathodic protection, metal coating protection and conductive anti - corrosion coating. The analysis results show that the reason why grounding grid was corroded is that the electrochemical inhomogeneity of metal and dielectric formed corrosion cell and corrosion types vary in different soil environments. The anti - corrosion measure of increasing section of grounding body based on the local and average corrosions of grounding grid is more reliable, but the loss is very large. [ABSTRACT FROM AUTHOR]

Aiming I he problems of the traditional non - sequential Monte Carlo sampling method in power system risk evaluation, such as repeated sampling and long period of simulation, this paper proposed the improved Monte Carlo algorithm. It is a method that firstly formulates the zero - variance approximate function of each element to gel their optimal parameters, and then samples by scattered sampling method. Through the combination of the two methods, scattered sampling and Monte Carlo, the sampling efficiency of Monte Carlo is enhanced, as well as the calculation speed. Compared with the traditional sampling methods (scattered sampling and cross - entropy method) based on the IEEE RTS substation, the improved method has an advantage in little probability event. [ABSTRACT FROM AUTHOR]

On the basis of expounding the lead - acid batery deterioration and restoration technology，through the integration of the relevant research results，this paper developed pulse sets in addition to sulfur，equalizing charge detection and protection of three - phase accumulator maintenance technology，multi - channel output cycle in addition to the working mechanism of sulfur，and batery networl of real - time monitoring function in a body of the intelligent battery online monitoring and maintenance management system. The practical application shows that this system realizes network unified management of battery，accurate discrimination of battery performance and battery online desulphurization，which make the technological index reach the target value，meeting the requirement of onsite operation. [ABSTRACT FROM AUTHOR]

In order to provide technical support for preventing closing breaker with ground-wire, a new detection method based on response analysis is proposed in this paper. It is a method by which excitation signal is exerted to primary device at suitable location in substation so as to determine whether there is any ground-wire still hung on the device by analyzing the characteristics of the response signal; the impedance of the primary winding of transformer varies with the variation of signal frequency, based on the theory selecting appropriate signal frequency which can effectively identify ground- wire grounding and transformer neutral point grounding. On the other hand, it can effectively avoid the influence of voltage transformer. Experimental results prove the practicality of the proposed method. [ABSTRACT FROM AUTHOR]

Aiming at the problem of bird-repelling which exists in the substation, the drawbacks of traditional bird-repelling devices was investigated, and a new type of substation separate intelligent bird-repelling system based on ZigBee network, ultrasound technology and Doppler effects was designed where the traditional bird-repelling device was divided into two separate devices, detection equipment and drive equipment. The method of laying out the detection equipment and drive equipment were explored according to the scope of them. Communication network needs to be established among the equipment with the adoption of ZigBee technology, making detection and drive equipment to cooperate to complete the bird-repelling work and realizing the total coverage of the bird-repelling system in the substation. A kind of ZigBee network solution was provided based on CC2530 and Z-Stack protocol stack, at last, the implementations of the system were conducted, and the performance testing was undertaken in one substation. The results indicate that the bird-repelling system has provided a new solution for the bird-repelling of the substation with the performance of wide scope, high efficiency and ease of administration. [ABSTRACT FROM AUTHOR]