CORBA-BASED INTEROPERATION IN SUBSTATION AUTOMATION SYSTEMS

The International Electrotechnical Commission (IEC) 61850 standard describes the communication inside the substation automation system (SAS) setting the base for new interoperating devices that share information using the Ethernet network infrastructure. More recently, the request of time synchronization among SAS components for the timestamping of critical events or synchrophasor measurement has generated a very high interest in the IEC 61850 working group for distributed synchronization protocols like IEEE 1588. This paper analyzes the current situation, matching different implementations of the IEEE 1588, and their respective accuracy, with the requirements of typical SAS applications: from the millisecond synchronization accuracy required by fault recorder application to the microsecond required by the sampled values (SV). The main focus of this paper is on the integration of IEEE 1588 with real already existing systems, and the goal is the performance comparison of different architectures. For these reasons, experimental tests have been carried out using a real SAS network infrastructure [redundant gigabit optical fiber Ethernet network managed using rapid spanning tree protocol (RSTP)]. The results show that, under ideal conditions, the IEEE 1588 protocol can achieve synchronization accuracy slightly worse (80 ns) than legacy IRIG-B systems (15 ns). However, IEEE 1588 makes possible a great cabling reduction and a simplified maintenance when synchronization is directly transferred on the SAS system bus. On the other hand, experiments highlight that nodes connected through a legacy RSTP infrastructure, which does not support IEEE 1588 messages, can lose the time synchronization in the case of network traffic or reconfiguration of the network. Therefore, the integration of IEEE 1588 over existing IEC 61850 station bus is basically a tradeoff between installation costs and performance since it requires the replacement of already installed Ethernet infrastructure. In the last part, this paper analyses the challenges for the next SAS generation that has to combine on the same plants the high accuracy IEEE 1588 implementation with high-availability protocols based on IEC 62439. Since the lifetime of an SAS is more than ten years and the adoption of these technologies takes several years, some solutions that introduce synchronization and high-availability protocols guaranteeing compatibility with existing technologies have been analyzed, too. For instance, an adaptation block that (when attached to a high-availability network) reconstructs the interface signals (e.g., synchronization signals) required by traditional bay has been proposed.

The rapid pace of technological development shows no sign of slowing. Technological development has had and is still having a big impact on Substation Automation Systems. Nowadays, with the move towards electrical utility deregulation throughout the world, it is imperative to exploit the latest trends. Utilities and industry must be able to provide an even more efficient and cost-effective service. They must ultimately optimise their assets and stay ahead of the competition. This paper describes, by reflecting back on Substation Automation history, today's developments and how users could utilise them in their Substation Automation Systems. In addition a summary of the gained benefits is given and some references are shown.

Electrical substation is one of the most important parts of power system network. Over the years, the substations have undergone several structural and technical modifications. The IEC 61850 standard launched by the International Electrotechnical Commission (IEC) has created a strong platform for modern Substation Automation Systems (SAS) based on Digital Communication Systems. To increase the system reliability and efficiency, the Substation Communication Network (SCN) should have a quicker response, especially during electrical faults. According to the IEC 61850 standard, the end-to-end (ETE) time delay for transmission and control of data has to be less than 4-ms which is achievable when the data packet size is smaller. However, when the packet size is larger, it exceeds the delay time limit. Hence, sending smaller data packets could be a solution, but sending too many smaller packets might create congestion in network incurring another delay issue. This paper presents a different network topology that is designed in Optimized Network Engineering Tools (OPNET) environment which is capable of transmitting and controlling larger data packets within the 4-ms time delay limit as recommended by the IEC 61850 standard.

SAS enable them to meet workplace challenges and make sure that they are exploring accessibility ideas with the support of a better use of tools of monitoring. This study aims to shed light on the critical role of SAS in energy project management. It will provide actionable strategies for project managers to harness creativity and innovation, ultimately leading to more successful and sustainable project outcomes. By bridging the gap between creativity and project success, this research will contribute significantly to the discourse on innovation and leadership in the energy sector. A sample of 100 respondents has been chosen from the relevant group practising SAS at their workplace. The data has been further executed with the help of relevant approaches of PLS software where statistical operations are applied to ensure validity and reliability in the output. The output justifies that there is a positive role of SAS in increasing the project success parameter because of positive implications in the perspective of a theoretical outline and solutions for the problem-solving techniques application. The study recommends that policymakers should facilitate the project managers to meet the challenges in the energy sector by implementing SAS. The study has positive implications and is helpful for the project managers and the decision-makers in the energy sector to apply the modern tools of SAS.

Communication network is the infrastructure of intelligent substation in smart grid, and it plays a vital role in substation automation system (SAS). The traditional Ethernet network cannot fulfill the requirements of SAS, and these requirements consist of centralized network management and control, dynamic resource allocation flow. In this paper, Software Defined Network (SDN) is used to manage and control the communication network of SAS. Based on SDN and IEC61850, firstly, shortcoming of current SAS network management is illustrated. Then, some new features about SAS have been designed, such as realization principle, application technology, function modules and workflows of network management. Finally, simulation experiments are designed to verify network management function. The simulation results validate the effectiveness of dynamic and real-time supervision in SAS communication network.

Object-oriented technology is very helpful in improving the reliability, portability and maintainability of engineering softwares. This paper applies the idea of object-oriented technology in the substation automation and realizes an object-based distributed substation automation system. The resulting substation automation system is logically composed of system units and the units themselves are composed of objects so that the entire system shows an object hierarchy. By this structure, the distributed substation automation system will be characterized with reliability, portability and maintainability.

On behalf of the editorial committee of International Journal of Automation Technology, I would like to sincerely ask all of you a favour of me to activate this journal since I am convinced that the automation technology is indispensable to the convenience and prosperity of human being. The automation technology began with the development and introduction of numerical control (NC) machine tools in the latter of 1950s. In 1960s, the technology was applied to assemble electric goods and automobiles together with the development of a wide variety of automationrelated methods such as industrial robots, semiconductor technologies and so on. In 1970s, this tendency had greatly affected the automation of production systems, which was called FA (Factory Automation or Flexible Manufacturing System), that is, flexible systems to rapidly cope with the change in the sort and quantity of products. The construction of FA is still continuing even now. The current state of art in production automation is the evolution by making the most of IT (Information Technology), where there are infinite tasks to be solved, for example, the cooperation with design, manufacturing and sales, life cycle control of products from production to waste by IC tag, product liability management, lean production taking account of environment protection and energy saving, product development with individuality and characteristic, production sustaining human skill, manufacture of high value-added products, development of future products, etc. After the bubble disruption in 1990, Japan has been suffering from the economical recession for 15 years, thus resulting in hanging low of automation technology development as well as decreased equipment investment. In addition, our serious problem in Japan is the disappearance of valuable technologies and manufacturing spirit by the mass retirement of engineers who have born the automation technology and supported excellent product manufacture. Thus, it is an important issue to improve and develop the automation technologies further. From the above mentioned viewpoint, the journal focuses on the advanced automation technologies ranging from fundamental technologies to a variety of industrial applications, which meet the requirements, especially from industries. The journal covers all sorts of automation technologies regarding design, manufacturing, assembly, inspection, transportation, logistics, machine tools, robotic system, control system and instruments, and so on. There are some journals with respect to the automation specific to scientific and fundamental research, however, no journal exists, which aims at providing engineering researches and practical developments. Thus, the journal takes up a large amount of practical examples relating advanced automation technologies as review papers, research and development papers, news and interview so that the readers can take interest in the journal. The editorial committee wants IJAT to serve engineers and managers for the requirement of automation technology developments, and is all concerned for your contribution to IJAT.

With the rapid application and development of artificial intelligence technology in the civilian field, the research on intelligent combat and command systems in the military field is also intensifying. In order to improve the cognition and decision-making ability of international command and control system, this paper elaborates the overall technical framework of the system, and brings forth intelligent solutions and development suggestions in situation cognition, planning, decision making, and action control.

Improvement of electricity distribution management is stimulated by energy market deregulation and dictates investment choices for power stations, distribution lines, remote control centres and electrical substations. The aim of this paper is to look at various strategies followed by utilities for the choice and installation of protection and control systems in electrical substations. It focuses on substation refurbishment corresponding to the most common situation found in industrialised countries. The first part of the paper briefly introduces the main reasons for modernising the substation level. It then looks at the various industrial policies that may be adopted depending of the utility objectives.

This paper describes the status and trends of the technical activities ongoing, as well as background circumstances, in protection and control systems in Japan to achieve ensuring stable power supply, improving efficiency, reducing cost, and protecting the natural environment at the same time. Several measures and systems accomplished to establish a reliable power supply network system are reported. Status on applying IT technologies to wide area communication and substation facilities are explained with several examples. Approaches to improve the reliability in the distribution substation are presented, followed by the anticipated effects of introducing distributed generation into the distribution networks.

The analysis of different power system events is important for the successful operation of the system and the optimal design and configuration of protection and control systems. The paper analyzes the types of system events, available data sources and requirements for the development of hierarchical event analysis systems. The need for common record formats and configuration data are discussed. The importance of accurate time-synchronization and methods to achieve it is also described.

As the power grids are integrated into one big umbrella called a communication protocol plays a key role in successful operations. The successful deployment of smart grid interoperability is a major hurdle that must be overcome. The micro grid, a small power system that distributes energy resource, is operated in diverse regions. Different vendors use different communication protocols in the operation of the micro grid. Recently, the IEC 61850 has been legislated to solve the interoperability problems in power utility automation. The present paper presents a micro grid system based on the IEC 61850 protocol. It consists of a micro grid monitoring system, a protocol converter that transforms serial data to IEC 61850 data, and distributed energy resource controllers for diverse DER nodes. A developed communication gateway can be deployed for DER controllers with serial links to exchange data with IEC 61850-based devices. The gateway can be extended to IEC 61850-based distribution automation systems, substation automation systems, or SCADA.

Over a number of years researchers have reported associations between osteoporosis or low bone mineral density and signs that can be detected on dental radiographs, particularly in the width of the inferior mandibular cortex and the texture of the trabecular bone. As patients visit the dentist more regularly than they visit their doctor, there is the possibility that such signs could be used as a means of identifying individuals at risk of developing osteoporosis or suffering from consequent fracture. This paper reviews the historical background behind this research and the current status, including recent developments in automation of measurement using computer image analysis.

A UTOMATION, it would seem, is here to stay. Advantages in speed and accuracy seem likely to make the use of computing machinery more common, despite the relatively high initial cost. In view of recent developments in automation and high-speed data processing, it is appropriate to ask, Do possibilities for automation exist in cartography? And if so, where can these possibilities be found? In order to answer these questions, the preparation of maps should be viewed as a complex dataprocessing system. Certain similarities then become apparent between data processing in general and cartographic processing in particular.

Distribution protection relays have changed significantly during the last decade. These advanced multifunctional IEDs are today at the bottom of the communications architecture of many substation protection, automation and control systems (SPACS). Testing of these devices requires good understanding of their functionality, the available tools and the purpose of the test. (4 pages)