wilamowski-b-m-irwin-j-d-industrial-communication-systems-2011

29-4 Industrial Communication Systems
are listed in the IEC 61226 recommendations. There are typically three classes of instrumentation and
control functions for European pressurized reactor (EPR):
• F1A functions, which are performed by the reactor protection system, RPS (automatic reactor
trip, actuation of the engineered safeguard systems and their supporting systems), and by the
priority and actuator control system, PACS. This is the strongest safety rule where the behavior
must be deterministic.
• F1B functions, which are performed mainly by the safety automation system (SAS) and by the
safety information and control system (SICS). In this class, the behavior must be predictive.
• F2 functions, which are performed by the process automation system (PAS); the process information
and control system (PICS); and the reactor control, surveillance, and limitation system
(RCSL). F2 functions can be either seismic classified (F2E functions) or non-seismic classified
(F2N functions).
The priority rules are defined as follows:
• Higher class functions have priority over low-class functions; so, F1A has priority over F1B,
which has priority over F2 functions. Higher class functions must not be disturbed by lower class
functions.
• The order of priority within each control system is defined as follows: system and component
protection has priority over automated functions, which has priority over manual functions.
Automatic functions can be switched off if the process conditions allow it.
29.3 Power Plant Information Systems
and Extra-Plant Communications
Power plant information system plays an important role in operational performance. A well-designed
power plant information system helps to achieve operational efficiency by providing secure access to the
right information at the right time to the right person. It concerns in particular the integration of power
plant information system with enterprise business information system. It represents a challenging task
because these systems do not have a same lifecycle in terms of evolution and technology used.
The need of accessing process data for doing business intelligence or e-monitoring from a remote
expertise is the major motivation. Having standardized power plant information model and business
meta-model helps to reduce complexity in the integration of power plant information system and business
information system. IEC TC57-WG13 Common Information Model (CIM) provides a standard
and basic description of power plant assets.
29.3.1 Common Information Model
The most important extra-power plant communication is the information exchange for real-time and
non-real-time information, used in the planning, operation, and maintenance of power systems. IEC
TC57 WG3 and WG13 have defined, respectively, telecontrol protocols and energy management system
for real-time and non-real-time power control between the grid dispatching center and a power plant
control room.
The European Transmission System Operators (ETSO) organization also works closely with IEC
TC57 to define the CIM, IEC-61970-301 as the reference model for electric energy trading and for the
power system operation. The CIM provides, for example, a standard and basic description of power plant
assets. Generation, load model, outage, SCADA, energy scheduling, and financial packages (Figure 29.4)
are typically defined in the TC57-WG13.
© 2011 by Taylor and Francis Group, LLC