ML24306A074
| ML24306A074 | |
| Person / Time | |
|---|---|
| Site: | Pennsylvania State University |
| Issue date: | 11/04/2024 |
| From: | Penn State College of Engineering, Pennsylvania State Univ |
| To: | Office of Nuclear Reactor Regulation |
| References | |
| Download: ML24306A074 (9) | |
Text
Description of Hardware The upgraded Reactor Safety System (RSS) at PSBR will be a hybrid system integrating the following major subsystems:
Wide Range Channel Power Range Channel Tricon Safety System
Wide Range & Power Range Channels The Wide Range Channel and the Power Range Channel provide reliable neutron flux measurement from reactor shutdown to reactor full power level or from 1 nV to 1010 nV in a harsh environment. It is designed to measure neutron flux while operating in a high gamma radiation and electrically noisy environment, and it also monitors fuel temperature. Both channels are hardwired analog systems composed solely of passive and active electronic components. These two analog channels are part of the RSS at PSBR and have been in service since 1992.
Tricon Safety System The Tricon Safety System is a triple modular redundant (TMR) safety controller platform designed for safety-critical applications. It uses three independent microprocessors that continuously check each other to ensure high reliability and fault tolerance. The TMR architecture ensures that the system remains fully operational even if one of its processors fails. The application program deployed on the Tricon Safety System is designed to replace the analog relay logic circuitry in the RSS, specifically for executing scram and interlock functions. Tricon Class 1E Grade refers to the specific qualification and reliability standards that the Tricon safety system meets for use in nuclear power plants, particularly regarding safety-related systems.
The Tricon Safety System (V9-V10) has received Class 1E qualification from the USNRC, which is approved to be used in nuclear power plants for critical safety applications.
Software Development Plan (1 of 3)
Project Scope and Objectives - The application software is designed for deployment on the Tricon Safety System at PSBR, replacing the analog relay circuitry of the RSS by replicating its established safety functions.
Requirements and Specifications - Details both functional (what the software should do) and non-functional (performance, security) requirements that the software must meet.
Development Methodology - The software development methodology for the application program will follow the waterfall model. The development process shall include the following phases with documentation and sign-off for each phase before advancing to the next.
Development Phases I. Requirement Definition - Define the functional requirements for the application program on the Tricon Safety System for the Reactor Safety System (RSS) at PSBR, each function must outline what the system is expected to achieve, along with clear pass/fail criteria to ensure each requirement is verified during testing.
II. Design, Test, and Refinement - Design application software to ensure all core functions were covered. Bench tests using simulated inputs then verified the program's performance, followed by a detailed review to compare test results with pass/fail criteria. Any issues identified were addressed through refinements to the program, optimizing it for reliable operation and ensuring all requirements were met.
III. Implementation & Commissioning Test - Install the application program in the operational environment and conduct commissioning tests to confirm it functions as designed.
IV. Deployment - Update SOPs and design documents. Provide training for operators on system functionality, controls, and safety procedures.
Software Development Plan (2 of 3)
Team Roles and Responsibilities:
Application Program Developer: Mr. Adams Tong, Sr. Research Engineer at PSBR.
Technical Reviewer: Mr. Daniel Beck, Engineering Project Manager at PSBR Project Manager: Dr. Jeffrey Geuther, Associate Director of Operations at PSBR Technical Consultant: Mr. Ryan Marcum, Technical Sales Consultant at I & C Operative.
Timeline and Milestones - TBD.
Risk Management - Using the original RSS schematic as the blueprint, we do not anticipate great challenges or risk in the creation of the application program. In addition to the technical support from the system manufacturer, we have contacted Mr. Ryan Marcum, who has years of experience with the Tricon Safety System, to provide technical consulting service as needed.
Software Development Plan (3 of 3)
Testing and Quality Assurance - Software Validation Test shall be conducted during development phase II. Commissioning Test shall be conducted during development phase III.
Maintenance and Support - Post-release maintenance will be determined after PSBR engineering has received maintenance training from the manufacturer.
Software V&V & Documentation Plan Both Software Validation Test and Commissioning Test shall follow approved validation test procedures created by the developer. Test procedure shall be approved by the reviewer and/or the project manager. The test procedure shall include the following subsections:
Purpose and Scope - Define the objectives, scope, and intended use of the V&V activities.
V&V Approach - Describe the overall approach for the V&V Activities.
V&V Activities - Outline validation methods for each test case and metrics for validation success.
The validation test shall be conducted by the developer, with a member of the operations team present. The developer shall submit a validation test report to the project manager for review and final approval at the conclusion of the validation test.
The validation test report is the validation test procedure with the test result for each test case.
Hardware Test Plan The Tricon Safety System was commercially developed by Framatome Inc. Factory Acceptance Testing was conducted by Framatome in 2020 in accordance with the Hardware Validation Test Procedure [Doc #: 63-9302046-HVT-002]. The test results are documented in the Factory Acceptance Test Report [Doc #: 66-9302047-FATR-000].
Test Case #15 to Test Case #19 are hardware validation test for the Tricon Safety System.
The Commissioning Test will function as the comprehensive hardware test for the integrated system, covering the Wide Range channel, Power Range channel, and Tricon Safety System.