Radiation monitoring system for Kudankulam NPP:
project development and implementation goes ahead
by Daria Plyshevskaya
Upon results of the tender, PROM Engineering
(Russia) was awarded a contract for the manufacture and supply
of an automated radiation monitoring system (ARMS) in the framework
of constructing two power units of Kudankulam NPP with WWER-1000
reactors in India.
The Kudankulam NPP ARMS has a number of considerable
advantages when compared to the existing systems at Russian nuclear
plants today due to the great reliability provided by its system
structure, the wide range of objectives that it can achieve, the
use of state-of-the-art instrumentation with wide measurement
ranges, software usability and equipment serviceability.
ARMS is the major system for control of radiation
safety at the NPP. It allows damage to one or other of the protective
barriers to be identified at an early stage and prevents the penetration
of radionuclides into the environment. Information exchange between
the Automatic Process Control System and ARMS enables continuous
analysis of the NPP to be carried out and failures with the main
process equipment to be predicted.
ARMS combines both continuous and periodical
monitoring of the radiation process
monitoring of the radiation status in a power unit and at
monitoring of gaseous and particle releases into the atmosphere
monitoring of radionuclide releases into the open aquatic
monitoring of the spread of radioactive contamination
monitoring of collective and individual radiation doses received
The ARMS system for use at a nuclear plant is
a complex system worked out according to an hierarchical approach.
It consists of self-contained subsystems for routine operation
and for emergency control. For emergency control the subsystems
are made with dual redundancy for measuring channels, communication
and power supply lines. It must be able to function for all the
types of NPP operation, including design basis and beyond design
basis accidents, right up to NPP decommissioning.
Work on monitoring the scope for optimization
at the Kudankulam ARMS has gone beyond the period of detailed
project development. The optimization of the ARMS project focused
on the selection of the most informative parameters for monitoring
at the NPP, which is equipped with a WWER-1000 (pressurized water
reactor) type reactor. This has lead to the complete reconsideration
of the whole project bearing in mind the new capabilities of the
latest up-to-date equipment (computer facilities and measurement
instrumentation) and the latest normative requirements. Furthermore,
the main aims were was to consolidate the maximum possible number
of radiation control objectives within a single automated system
and to assign main monitoring functions to the measuring of channels
in permanent automatic mode.