| Takashi Kobayashi | Switchgear Design Dept., Kokubu Engineering & Product Div., Hitachi Works, Power Systems, |
| Eiji Ogawa | Switchgear Design Dept., Kokubu Engineering & Product Div., Hitachi Works, Power Systems, |
| Atsushi Yanaoka | Switchgear Design Dept., Kokubu Engineering & Product Div., Hitachi Works, Power Systems, |
| Mitsuo Sato | Switchgear Design Dept., Kokubu Engineering & Product Div., Hitachi Works, Power Systems, |
As regards protection relay systems that shoulder the burden of protecting and controlling electric power systems and equipment, as a result of the rapid popularization of Internet and intranet systems in recent years, information-communication technologies and digital technologies are being applied in order to improve equipment performance and save labor costs incurred in on-site operation and maintenance by means of remote supervision. Likewise, as regards a protection and control system for a distribution substation, digital protection relays have generally been used, and space has been saved by combining relay elements, and "maintenance-free" operation has been achieved by means of self-diagnosis tools. Aiming to contribute to further improvement in reliability, reduced total costs by integrating functions, and streamlining of operation and maintenance, Hitachi is developing a protection and control unit for distribution substations. The protection and control functions are combined in one unit, however, they are independent from each other. In addition, a web server is also incorporated into the unit, thereby allowing the unit to be operated remotely from distant locations. Moreover, to simplify complex system fault analysis, it provides a fault-recording function that uses a general-purpose analysis tools utilizing data based on the COMTRADE (common format for transient data exchange) format.
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The Hitachi Hyoron (Japanese Only) |
digital protection unit, distribution, protection and control system, relay, intelligent electric device
