Research on Testing Technologies of Network System in Smart Substations

The network structures of smart substations and the characteristics of industrial Ethernet switches are analyzed.The testing technologies of network systems based on smart substations are specifically elaborated.A viewpoint is proposed that special testing policy&method of smart substation networks should be followed,so that the results can reveal the real network data exchange performance of the whole station.This view ensures the safety and stability of smart substations and lays a foundation for future upgrades and expansions.

Smart Substation Integration Technology and Its Application in Distribution Power Grid

At present,smart substations use the IEC61850 standard based on the architectural framework of three layers and two networks to realize information digitization and advanced applications.Although the smart substation offers many improvements in design,equipment manufacturing,and construction,the intelligent devices used in smart substations are costly,and are also difficult to maintain since they are dispersed within a single unit.Functionality optimization and device integration,thus,have become important issues in smart substation development.This paper presents an integrated solution and implementation process for a smart substation system.In the process layer,an integrated intelligence component is developed that functions both as an intelligent terminal and a merging unit.In the bay layer,an integrated station-area protection measurement and control master device is designed to achieve such functions as protection,monitoring,control,fault recorder,and power quality monitoring.Finally,in the station control layer,an integrated information platform is established to bring together various system functions and to promote interactive sharing.Integration technology improves the economy and practicality of the smart substation,especially in a distribution power grid.

Hierarchical protection control system of smart substations

This paper analyzes the problems of the relay protections and secondary circuits of traditional substations,and introduces the hierarchical protection and control system of smart substations based on the technologies like IEC 61850 Standard,electronic instrument transformer,process level network,and wide area optical fiber communication network,etc.The hierarchical protection and control system includes three levels:local area protection,substation area protection and control,and wide area protection and control.These three levels are combined to solve the problems of the relay protections in traditional substations,thus improving protection performance and control capability of the system.

Shared-network scheme of SMV and GOOSE in smart substation

The network structure of the smart substation in common use was introduced,and the technical problems of the shared-network of sampled measured value(SMV)and generic object oriented substation event(GOOSE)were analyzed,such as the processing ability of network device and the intelligent device,the data real-time property and the network reliability,the effects to the substation in the condition of network fault,etc.On this basis,the feasibility of the shared-network of SMV and GOOSE was discussed,the implement scheme was presented,and eventually the solution of the shared-network of SMV and GOOSE was put forward,which based on the applications of the message priority control,restricting the switch number,virtual local area network(VLAN)and GARP multicast registration protocol(GMRP)classification flow control,flow rate limiting,etc.In the test-bed,the cases of shared-network and separate-network of SMV and GOOSE were compared and analyzed,and the result was valuable for reference.

Big data compression processing and verification based on Hive for smart substation

The capacity and the scale of smart substation are expanding constantly,with the characteristics of information digitization and automation,leading to a quantitative trend of data.Aiming at the existing processing shortages in the big data processing,the query and analysis of smart substation,a data compression processing method is proposed for analyzing smart substation and Hive.Experimental results show that the compression ratio and query time of RCFile storage format are better than those of TextFile and SequenceFile.The query efficiency is improved for data compressed by Deflate,Gzip and Lzo compression formats.The results verify the correctness of adjacent speedup defined as the index of cluster efficiency.Results also prove that the method has a significant theoretical and practical value for big data processing of smart substation.

Propagation Delay Measurement and Compensation for Sampled Value Synchronization in a Smart Substation

Reliable sampled value(SV)synchronization is used to ensure the reliability of protective relaying in a smart substation based on IEC 61850.In this paper,an SV synchronization method based on SV propagation delay measurement and compensation is proposed.The method does not depend on an external reference clock and has higher reliability than existing ones.The core issue in the proposed method is to measure the switching delay.The following steps are undertaken in this work:First,the composition of SV propagation delay in a smart substation is analyzed.Second,a new switch with the capability of switching delay measuring and recording is presented.Third,two laboratory tests are conducted to study the measurement accuracy of the switching delay.Finally,an SV synchronization method is presented and its application is tested on a busbar protection system to demonstrate that the proposed method can achieve SV synchronization effectively.Test results show that the measurement is sufficiently accurate for the SV propagation delay compensation.The proposed method also shows that the reliability of the protective relaying in a smart substation is significantly improved.

Distributed Protection for Smart Substations Based on Multiple Overlapping Units

Taking advantage of the information sharing mechanism in smart substations,a distributed protection based on multiple overlapping units is introduced in this paper.The area division and the construction of protection units are studied based on the principle of differential protection.Mutual perception and information interaction among units,calculation with multisource information and coordinated protection schemes are proposed to improve the reliability and adaptability of the substation protection system.A multi agent system(MAS)approach is used to model the units’working process in various situations,such as communication failure and sampled data failure.Test results demonstrate that the method can accelerate the backup protection as well as reduce the power-off range.

Solutions to Support Smart Substation Project

Based on the analysis and inductive research on the current problems, the solution to support the smart substation project is put forward to improve the construction efficiency of a smart substation, guarantee safety of operation and maintenance, and meet requirements for the design, commissioning, and operation and maintenance of a smart substation. The solution is to add innovative thoughts of "integration on design and configuration," "SCD file decoupling," "visualization of virtual secondary circuit" and "SCD file control" into the PRS-7000 series tool. As an integration tool for the design and configuration of a smart substation, PRS-7001 has effectively inherited the knowledge and operation practice of the design institute by applying a typical design template and a virtual terminal connected database. The PRS-7002 secondary circuit visual tool can display the virtual circuit connection and configuration of the SCD files in a multi-function and multiperspective way. Besides, it can effectively support commissioning, defects eliminating and overhauling. The PRS- 7003 SCD control tool has not only the off-line control functions for version management and tracing, inspection and warning for information changes and scope definition for upgrading of devices, but also the functions of process level configuration for the device and CRC online comparison.

Research on Plug and Play of IED in Smart Substations

This paper focus on the problems with smart substations such as long period of construction and design, difficulties of debugging and maintenance. According to the whole process of designing, construction, operation and maintenance of smart substations and characteristics of IED, the plug and play technology on the whole life cycle of a smart substation is proposed. Standardized virtual terminal description is used in matching the signals, standardized definitions and order of virtual terminal is used in connecting the signals, and management server is used in managing IED failures and backup. The plug and play technology can effectively improve the efficiency of design, construction, operation and maintenance of smart substations.

Trend of Standardized Design and Modular Construction for Secondary System of Smart Substations

Smart substation projects have been developed for nearly five years; it is necessary to unscramble the technology route in the whole process in order to provide a direction for the development of engineering construction. Based on the actual status quo of design and construction of the secondary system, the authors analyze the existing problems and the situation, and discuss the trend of standardized design and modular construction of smart substations.

China’s Three Gorges Reservoir Area of Intelligent Substation Project Supervision Work Method Is Discussed in This Paper

The ecological environment promotes the construction of smart grids, while the smart substation is the key to the construction of smart grids. Based on the supervision of the Zigui 220 KV smart substation project in the Three Gorges Reservoir Region of China, this paper studies how to well create the supervision for the smart substation project construction. With the research focus of “four-control, two-management and one-coordination” in the supervision and according to the problems and experience in the project construction, some reasonable suggestions are put forward, and then the accumulated methods and experience by supervisors when they are engaged in the supervision for the smart substation project construction are summarized.

Smart Power Substation Development in China

Over the past decade,China has undertaken substation intellectualization of more than 2000 substation operations in three stages.Much experience has been achieved during this developmental period.In this paper,the status of smart substation development in China is systematically presented,as well as future directions of the smart substation,such as adoption of the hierarchical protection and control system.