Project preparation phase

Considering that the decision of a new installation has been made (based on the results of a feasibility study, economic aspects, risks analysis, etc.), the I&C project can be engaged. The objective of this “preparation phase” is to prepare the tender that allows afterwards to contract the I&C system implementation.

2.5.1.1. Project plan and project management

The most important and perhaps the most decisive aspect for the success of an I&C project is the project management throughout the entire implementation process of the I&C systems. Once the decision of constructing a new NPP has been made, a project leader for I&C systems needs to be appointed, who will be in charge of mediating between the involved parties and ensure that the I&C project will be successfully completed.

A project plan has to be developed to allow the work to be done cost effectively, in a timely manner, and with minimal risks. This project plan includes, in particular:

— The project team organization, in which all the stakeholders (operator, process maintenance team, engineering team, etc.) must be represented;

— The different project phases, from the system specification to the commissioning, and the activities to ensure the acceptance of the system;

— The procurement and contract management arrangements;

— The documentation that has to be delivered during the project, in particular for an I&C project. This should include the items referenced in Section 2.5.2;

— The project planning, which establishes a schedule for the overall I&C project; identifying the approximate human resource needs, evaluating economic/financial resources for I&C;

Power plant Operation & Maintenance Specification & Requirements I&C System Specification Phase I&C System Design Phase I&C Systems Implementation

Integration tests

Validation of the System on site (SAT) Validation on platform (FAT)

I&C System Modernisation/retrofit Specification

Operation & Maintenance I&C System modification Design I&C Systems modifications Implementation

Decommissionning Modification Specification & Requirements New I&C Project ManagementI&C Modernization Management

FIG. 43. I&C project management.

— The interaction with the licensing bodies. A specific characteristic of a nuclear plant — and consequently of the I&C system — is the safety requirements. Therefore, interaction with the safety authority bodies must be identified from the beginning of the project;

— The quality management plan, which defines the quality management measures for the whole I&C life cycle to ensure that the I&C system is planned, manufactured, installed and operated so with adequate quality level.

A good quality management requires quality plans describing quality management measures from all parties:

the utility, the vendor and the subcontractors. The quality management planning should envelop but not necessarily being limited only to the following quality planning aspects that are especially applicable for digital I&C systems:

The following IAEA documents — although primarily dealing with modernization projects — are applicable to new I&C projects: Refs [17, 18].

2.5.1.2. Power plant operation and maintenance (O&M) specification and requirements

The first step of the project is the identification of the requirements specification for the various functions required for operating and maintaining the process. This will contribute to the definition of the I&C functions and associated requirements as identified in the functional view (see Section 2.3.1), in its environment (process, operator and maintenance).

Two main activities are performed:

(1) Functional analysis: Based on the plant process description, the functional analysis contains the definition of all the needed functions for operation and maintenance in different plant conditions (normal and abnormal).

The analysis of the “process-oriented” functions can be done in a top-down approach, where the top level represents the most general or fundamental objectives of the plant (generation of electrical power, protection from radiological hazards). The lowest level represents very detailed functions, which will be implemented, among others, in the I&C system or will be performed by an operator.

(2) Operational specification: Together with the functional analysis, the operational specification gives the basic philosophy of how the plant is intended to function in different conditions. At this stage, a task analysis is performed and the assignment of functions between human and system is done [19].

With new digital technologies used for HSIs, particular attention has to be paid to human factors acceptance by the operators [10].

The appropriate maintenance aspects of the I&C system have to be anticipated in the early stage of system design in order to ensure the following maintenance-related functionality:

— I&C system accessibility (especially during plant operation);

— On-line monitoring, alarming and event logging related to the I&C system performance, data networking and I&C system functionality;

— On-line maintainability;

— On-line software changes implementation;

— Configuration control;

— System administration;

— Sufficient scope of manuals, procedures and instructions for I&C system maintenance and administration;

— Maintenance requirements, such as hardware calibration, software backup, disaster recovery (in the event of total system failure), etc.

2.5.1.3. System specification

The system specification describing what is expected from the I&C system, as a basis for the collaboration with the I&C supplier, can be split into two parts. The first one is the detailed functional specification, which is the description of all the functions that must be implemented in the I&C system in order to comply with the O&M functional specifications. As a minimum requirement the detailed functional specification should define the following:

— Scope of input signals for each functionality (inputs from the process, signals from the process data base);

— Definition of algorithms/logic using input signals, constants and manually entered values;

— Scope of output signals (algorithm outputs, calculated values, output signals to the process);

— Basic HSI specification related to the HSI features associated with subject functionality;

— Functionality acceptance criteria requirements to be validated during the factory and site acceptance testing;

— The second one is the requirements specification, which covers:

— The I&C requirements in response to the O&M functional requirements (response time, accuracy, uncertainty, set points, etc.);

— The requirements for the development process from the basic design to the validation phases. Special attention should be paid in an early stage to identifying the rules, regulations, codes and standards to be followed during the implementation, as well as to the documentation provided and needed by different parties during the whole I&C life cycle. Particular attention has to be paid to qualification and validation;

— The requirements for environmental endurance (EMI, seismic, etc), and its operability and maintainability according to the safety importance or category of a given item. (Fault-tolerance, separation, redundancy, diversity, reliability, availability, testability, etc.).

Developing the requirement specification has proven to be the most important phase in all I&C projects.

Therefore, care should be taken to ensure that the specification is as complete, sufficiently detailed and comprehensive as possible, covering all plant states and assumed abnormal conditions.

Although focusing more on upgrades using digital instrumentation and control systems, Ref [20] contains detailed information on the requirements specification covering all the phases of a project, and so can be referred to also for new installations.

2.5.1.4. Simulator specification

Together with the specification of the I&C system, the specification of a simulator is highly recommended to be used for staff training before final commissioning of the plant (operator and maintenance teams) and for validation phases. Due to different environmental and technical circumstances the requirements for the simulator can be defined as a separate document.

2.5.1.5. Bidding and contracting

The recommendations presented in Ref [18] for a modernization of an I&C system are also applicable here for a first installation.