In this paper, we propose an information model supporting maintenance schedule coordination that flexibly accepts operators' requirements without any impact on other classes.
AbstractIn this paper, we propose IP-based computer network architecture for communications of facility maintenance information. This architecture enables realization of overlay network on the IP network to control the communications. We also examined a feasibility of the architecture with an experiment system. The result shows that the feasibility of the architecture is confirmed.Keywords: Facility maintenanceIP networkNetwork controlNetwork management Additional informationNotes on contributorsHiroyuki YusaHiroyuki Yusa received the B.S. and M.S. degrees in electrical engineering from Tokyo University of Science, Japan, in 1993 and 1995, respectively. In 1995, he joined the Central Research Institute of the Electric Power Industry (CRIEPI). His work has been in the research of distributed object, mobile agent, and active network technology and management systems for telecommunication networks. He is a member of IEEJ and IEICE.Tetsuo OtaniTetsuo Otani received the B.S. degrees in instrumentation engineering, M.S. and Ph.D degrees in computer science from Keio University, Japan, in 1992, 1994 and 2003, respectively. He has worked for Central Research Institute of Electric Power Industry since 1994. His work has been in SCADA systems for power systems and related data exchange. He is a professional engineer in Japan (Information Engineering). He is a member of IEEE, IEEJ, IEICE and IPSJ.Masahiro KuronoMasahiro Kurono received the B E., M.E. and Dr. Eng. degrees from Nagoya University in 1982, 1984 and 1999, respectively. He joined the Central Research Institute of the Electric Power Industry, Tokyo, in 1984. Since then, he has been engaged in research on the optical communications and the applied optical sensors.
We developed a SCADA server as a prototype to evaluate the applicability of IEC 61850 for the operation of large-scale photovoltaic (PV) generation systems. IEC 61850 and Web-service technology (IEC 61400-25-4) are applied to the data model and the server communication protocol. We also developed a test client for the conformance test, which was then executed. The result showed that the server conformed to IEC 61850 on the data model and protocol. Therefore, the applicability of IEC 61850 to the operation of a large-scale photovoltaic (PV) generation system is confirmed.
This paper introduces an architecture for computer communications applied to the operation and maintenance of power systems, the distributed real-time computer network architecture (DRNA). The architecture consists of four functional entities, namely, application programs associated with information models, an adaptation function, a transport function, and network- and security-management functions to achieve seamless, real-time, adaptive, and secure information exchange between distributed power system control devices. DRNA uses off-the-shelf and standardized technologies along with dedicated ones. Through careful application of the technology, an experimental setup of a distributed cooperative voltage-control network was constructed in a power system simulator to verify the architectural concept. The implemented technologies include mobile agents, middleware for prioritized and redundant communication schemes, label-switched and Ethernet-based transport networks, and a secure virtual private network. The experiment demonstrated the effectiveness of DRNA.
The paper proposes a basic design of IEC 61850-based communication adapter consisting of a common module that performs majority of communication transformation processing and a custom module that primarily performs the modulating and demodulating of payload information specific to each legacy communication protocol. The paper also shows an evaluation result of the proposed 61850 adapter with its prototyping in functionality and performance.
In this paper, we propose a communication method with IP-based wide area networks for SCADA systems. This method controls communications between substations and a control center and can be implemented as a communication middleware. The method supports functions for UDP-based transmission, route control of double route transmission, retransmission control and priority control. The functions work cooperatively to assure reliable and real-time communications. We also examined the effectiveness of the method under circumstances where there are not only transmission delay and route breakdown in network but also information congestion in computer. The results show that the proposed method is more effective for assuring real-time and resilient feature than TCP-based communication method.
To realize smart grid technologies such as load control, load leveling and demand response and solve problems caused by connecting many DERs to a distribution network, a distribution automation system (DAS) and energy management system (EMS) are respectively essential components. The communication of these systems has generally been handled by proprietary or vendor-specific protocols to date. Conversely, in intra- and inter-substation communication, the IEC 61850 has started to gain acceptance in supervisory control communication, due to its interoperability supporting multi-vendor environments. If the IEC 61850 can be applied to communications in DAS and EMS, this is expected to reduce the maintenance and equipment costs of each system. To do so, we must first evaluate the applicability of the IEC 61850 from the perspective of Logical Nodes (LN) and Data Objects (DO), which are data models defined in IEC 61850. This paper focuses on the DAS and building EMS (BEMS) and provides the evolution. We choose BEMSs because we expect many EMSs to be installed in homes or buildings in the near future and anticipate that building energy management functions will include home energy management functions. This evaluation result shows that most data items appearing on such communications can be represented as standard LNs and DOs but several data items cannot be easily represented as the same.
The authors have defined information models for power systems and devices based on object oriented technology, and designed Global and Local information models. The Global information model is used for EMS/SCADA and power systems operation in the control center, and the Local information model represents the behavior of components and devices in the power station and/or substation. Similar information models are being developed by IEC-TC57 as IEC61970 and IEC61850, and by EPRI as CCAPI and UCA2.0, aiming for standardization of open and multi-vendor systems integrated by cooperating EMS/SCADA systems, or equipment and devices. The information models are based on those of IEC and EPRI, and they are expanded for distributed processing in network environments. The authors implemented IEC61970 as the Global information model and IEC61850 as the Local information model with Java Class library. Also, the authors developed a prototype system that consists of a personal computer (PC) as control center, and 2 PCs as substations, and a network computing terminal with current and voltage sensors as another substation. The authors implemented agent applications for simple SCADA and simulation of the power systems devices (ex. Power Transformer, Circuit Breaker) to evaluate the cooperation between agent applications and the information model, and proved the usefulness of the information model. The authors examined the functional expansions for distributed environments, and clarified their ease of implementation and effectiveness.
This paper shows the design of a middleware for IP-based power system communication networks and evaluated results. The middleware ensures the quality of service (QoS) and reliability in three types of communications; mobile agent, message exchange and streaming data. The IP-based networks for power system operation and maintenance enable wide-area remote operation for SCADA and realize remote maintenance for facilities to promote flexible and efficient work. The networks are required to support real-time communications and take measures to avoid overloading and failures. These should ensure QoS and reliability for each application. However, as it is difficult for present IP network equipment to adapt to these requirements, we designed the middleware to satisfy them. We also implemented and evaluated this
