Tokyo Electric Power Co.(TEPCO) owns and operates diesel power-generation equipment that supplies power to the Tokyo Islands. To raise efficiency of the operation work, TEPCO decided to adopt a remote control and monitoring system, and MHI received the first order for the system. This system, controls and monitors the diesel generators, electrical systems and common auxiliaries at Kozushima Island from Oshima Island.
The system was finished its installation at the end of March 2003.
It was necessary to provide the same level of control and monitoring functions, quick response, and high reliability in the control room of the plant in conditions wherein communication is based on micro-wave and has a low speed (96 kbps x dual redundancy), and the communication speed changes according to weather conditions such as storms.
Moreover, to reduce operation expenses, cost reduction for the system was required, as is future easy system expansion.
As MHI's DCS, DIASYS Netmation is a system based on the latest general information technology and is available for control and monitoring under low-speed communication circumstances, Because its communication is Internet based, MHI is able to provide
solutions for all problems involved and has received a high evaluation from TEPCO.
Furthermore, a detailed description of DIASYS Netmation can be found at the following URL.
http://www.diasys-netmation.com/english/

• Control and monitoring operations of the Kouzushima Island power station are available from two Operator Stations installed at the Ooshima power station.

• The communication line is duplicated. One is TEPCO’s house line 96kbps (46kbps x 2 lines) and the other is NTT (Japanese telephone company)’s dedicated line 128kbps (32kbps is used for maintenance of the system)
• The condition of the diesel generators and ITV images can be monitored from the PDP large display (50 inches)
• Reports can be printed from a printer installed at the Ohshima power station

Ooshima control room

Example of supervision display

• Most appropriate system for remote control and monitoring systems of the Power plant on the Islands
  The system has CPU parts at the monitored station (Kouzushima Island), Operator station installed at monitoring station calls up the necessary data when required to the display. To ensure that the data size in the communication line will be at a minimum and so that it will be possible to achieve a fast response using a low speed communication line.
  Moreover, as the controller acquires the data and store it, the data will be stored without lack of data, even in the event of a communication failure.
  That is to say, DIASYS Netmation will be available for the low speed and an unstable communication infrastructure and the most suitable system for the remote control and monitoring system between the Islands power station.
• The system adopts the latest Information technology to achieve a cost effective and easily expansible system
  DIASYS Netmation adopts defacto standards and the latest general information technologies, such as IP protocol communication or Windows etc., so that general products such as PC can be adopted to achieve the lowest price.
  Moreover, system expansion, fusion of office automation is simplified.
• High reliability
  DIASYS Netmation is developed to be used as the DCS of thermal power plant, which high reliability is required. To achieve the high reliability, the system is designed to adopt appropriate redundancy, such as CPU, power supply and network etc.