Power Plant Upgrade

The challenge

  • Uneconomical operation of the power plant; there was the need for more than 3 persons at any moment for monitoring the engines’ operation at the power plant. Furthermore, engines were not operating at their optimum performance level.
  • Manual only control of the power plant’s produced power, voltage and frequency.
  • Control cards were based only on analogue control. Furthermore most of them had become obsolete during the years of operation.
  • Lack of any data recording system; no investigation of any incident could be executed.
  • Inadequate monitoring and alarms annunciation.
  • There was no permission to change operational parameters. Under/over frequency/voltage levels protection and operating voltage setpoint could not be changed.
  • Lack of any remote command system existence.
  • Lack of technical support for complex problems.

MAS solution

  • Installation of completely new power management control panels including state of art Woodward EGCP-3 controllers for nine main diesel generators of the plant.
  • Installation of a new Siemens S7-300 plc system for under-frequency and overload protection. Data and alarm logging (10msec accuracy) are also included while all station’s basic information is presented in a graphical way at a dedicated panel pc.
  • Installation of high-accuracy network analyzers for all main feeders of the power plant.
  • Central HMI (Scada) installation for monitoring and logging. Communication with diesel generator controllers, plc and network analyzers is implemented through Modbus protocol. All related information is presented with graphical and user-friendly way. Remote access (with security levels) is also fulfilled.
  • Installation of completely new engine protection and control panels for four 2 and 4 stroke engines of the plant with high importance. All the old cards were replaced with brand new plc system based on Siemens S7-300 series. New control and protection equipment was installed in the place of old obsolete analog equipment.
  • HMI (Scada) installation for monitoring and logging; each one of the four engines had its own dedicated HMI with all necessary equipment. Remote access was also fulfilled for all applications.


  • High availability of the power plant system due to the new sophisticated control units that were installed.
  • Multiple modes of operation of the power management system; automatic/fixed power export/manual mode have been implemented.
  • Economical operation due to high performance level that the engines are operating.
  • Precise control of generators’ voltage and frequency. Improved control of transient load demand.
  • Protection against total blackout by complex algorithms that ensure normal operation of the plant.
  • Capability of adding 1 or more new diesel generators which can run in parallel with the current installed units.
  • Electrical and mechanical data monitoring and recording of the whole plant.
  • User friendly HMI application with remote access from the central PPC offices in Athens.
  • 24/7 technical support.