New generation of advanced control system for large electric power network

Tokyo Electric Power Company (TEPCO) has integrated two SCADAs into one large system. The new control system manages approximately 150 power stations and substations, the maximum power demand totaling 6 GW. When we started development, we found conventional open distributed systems were not suited to developing true multivendor interoperable software. We also had other problems including a great number of facilities to monitor and severe response time requirements. We used a 64-bit Unix operating system conforming to the Single Unix Specification (SUS) as a development platform for multivendor interoperable system. The Very Large Memory (VLM) technology with 64-bit address space provided quick response time. This paper describes technology for building our control system, specifically 64-bit software adaptation and effective use of 64-bit address space. We also show significant improvement of response times with VLM technology in power applications