R1.02/01A BALAKOVO (Lots 1+2)

Balakovo nuclear power plant (NPP) consists of four VVER 1000/320 units that belong to a standard VVER 1000 reactor design. Nevertheless, Unit 1 and Unit 2 were commissioned in 1986 and 1989 respectively, and are equipped with the first generation of CIS which became obsolete, had low reliability rate, and provided limited operator's aid especially during transients, as well as accident conditions (if such occurred). The original CIS also did not comply with OPB 88/97 (General Guidelines on NPP safety) design requirements in the following areas:

Human-machine interface
Data processing
Provision of unambiguous information in compliance with the limits and conditions of the safe operation
Identification and diagnostic of reactor trip and safety system actuation;
Control room operator information support
This project therefore focused on replacement of the old obsolete Titan-2 upper logic with the "state of the art" HW and SW that would provide significantly more information to the control room personnel during normal operation, transients as well as accidents (SPDS), and would ensure high functional reliability with a minimum maintenance required.

The project scope of work included the CIS design, manufacturing the CIS components, development of CIS software (SW), programmable and technological applications, databases, and design documentation consistently with the requirements of the Russian regulations and standards. The project was implemented in three Lots as follows:

Lot 1 supply included the development of system application SW and support for CIS/SPDS.
Lot 2 supply included the CIS/SPDS hardware for Unit 1 and the CIS/SPDS set for the simulator training centre.
Lot 3 supply included the CIS/SPDS for Unit 2.
The replacement strategy included two phases; in the first phase, the CIS/SPDS was installed at Unit 1 for a trial period in order to detect any potential malfunctions or weakness of CIS and SPDS HW and SW. Only after successful trial operation phase, the CIS/SPDS equipment was installed at Unit 2. The commissioning stage of CIS/SPDS involved a comprehensive SW verification and validation, installation supervision, on-site functional test, trial operation, and fine tuning on-site.

This project aimed at upgrading the existing upper level of the plant information system called “Titan-2”, including in-core monitoring system (SVK) and operator work stations (RMOT), including all monitors and keyboards. The project particularly aimed at improving the system reliability, as well as increasing the system performance in terms of information provided to the operators. Old features of Titan-2 (HW and SW) were replaced by modern digital I&C technology, which provided entirely new spectrum of its functional capabilities, information processing and presentation to the control room personnel.

In addition to original Titan-2 function, a safety parameter display system (SPDS) has been integrated in Computer Information System (CIS), which ensures high reliability, surveillance and a comprehensive monitoring of the plant safety parameters.

The IAEA issue book for VVER 1000 reactors indentified a low reliability of I&C at VVER plants as well as inadequate accident monitoring instrumentation which is used to inform the operator of the status of safety related parameters as a safety issue.

Consequently the European Commission launched a project to address this issue in the framework of TACIS 2001 nuclear safety programme.

The overall objective of this project was to procure and install the new CIS and SPDS at Balakovo Unit 1 and 2.

Supply of CIS and SPDS for Units 1 and 2 of Balakovo NPP has been implemented by the supplier Data Systems & Solutions Ltd (DS&S). There were two contracts signed for the three lots which involved the CIS and SPDS supply for Unit 1, Unit 2 and Balakovo full scope simulator.

The first contract (27525: Lots 1 and 2) was signed in December 2003 and involved the design, manufacture, testing, adaptation to Russian language, certification, delivery; supervision of acceptance, installation, commissioning and functional tests; design and delivery of the necessary documentation, training and know-how transfer; provision of after-sales services, warranty over two years after provisional acceptance by the end User (Balakovo NPP).

Lot 1 included the system of application software development and support for CIS/SPDS (the System of the Development and Support). It was delivered to Russian Research Institute for Nuclear Power Plant Operation (VNIIAES) Moscow for their review.

Lot 2 included the CIS/SPDS for Unit 1 of Balakovo NPP and the CIS/SPDS set for the simulator training centre (CIS/SPDS for NPP and CIS/SPDS for Simulator Training Centre).

The second contract (75258: Lot 3), was signed in December 2003 and involved the supply of CIS/SPDS for Unit 2 of the Balakovo NPP.

DS&S implemented Lot 1 and Lot 2 in 2008; the Provisional Acceptance was signed by the End User in May 2008, and Final Acceptance was signed by the end User in June 2010.

DS&S implemented Lot 3 for Unit 2 CIS/SPDS in 2009; the Provisional Acceptance was signed by End User in December 2009, and Final Acceptance was signed after the end of Warranty, i.e. in March 2011.