Introduction of a Full-Digital Substation System for Stable Power Supply and Efficiency in Construction

East Japan Railway Company (JR East) and Hitachi, Ltd. have announced a joint initiative to develop a full-digital substation system fiscal 2025. The aim of this system is to enable dual configuration of transmission lines and protection/control functions within the substation premises, ensuring stable electricity supply for railways. Additionally, the system will improve efficiency in construction reducing the size of facilities.

The current protection and control system in substations requires separate metal cables for each data transmission, making it difficult to achieve redundancy in case of failures. The upcoming full-digital substation system will leverage fibre optic technologies, allowing a single optical cable to transmit multiple pieces of information from network equipment to on-site units. This will facilitate easy duplication of data transmission, enhancing reliability.

Field tests have already been conducted at the substation of JR East, confirming the communication status under real-world conditions. As a result, both JR East and Hitachi are confident in the practical usability of the full-digital substation system and plan to introduce it into operating facilities.

The features of the full-digital substation system include the stable supply of electricity through the complete dual configuration of transmission lines and protection/control functions within substations. In case of equipment failure, the system ensures continuous operation through redundant components, providing a more reliable electricity supply than before.

Furthermore, the system optimizes space and improves construction efficiency consolidating and downsizing the monitoring control panel and protective relay panel into an integrated unit. By adopting fibre optic technologies, the number of control cables is reduced approximately 90%, minimizing clutter and saving space.

To ensure compatibility and reduce the risks of implementing a new system, the full-digital substation system adopts the international standard IEC61850. This is a significant development as it marks the first introduction of a digital substation system based on IEC61850 a domestic railway company in Japan.

The full-digital substation system installation is scheduled to begin at the Koiwa AC substation in fiscal 2025, with equipment being gradually installed starting in fiscal 2024. The transition will involve the use of 22,000 volt equipment, followed the removal of old equipment and the installation of 66,000 volt equipment in subsequent fiscal years.

In conclusion, the collaborative efforts of JR East and Hitachi aim to achieve stable power supply and digitalization of substations through the introduction of a full-digital substation system. This system not only enhances reliability but also improves efficiency in construction, benefiting the railway industry.

Definitions:
– Substation: A facility that transforms voltage levels and controls the flow of electricity in power systems.
– Duplexing: The ability to create redundancy in data transmission, ensuring continuous operation in case of failures.
– Fibre optic technologies: Technologies that use thin strands of glass or plastic fibers to transmit data as pulses of light. These fibers offer high-speed, reliable, and long-distance data transmission.
– IEC61850: An international standard developed the International Electrotechnical Commission (IEC) for power utility automation, specifying communication networks and systems required in this field.

Sources:
– East Japan Railway Company (JR East)
– Hitachi, Ltd.