IEC 63046:2020

Overview

IEC 63046:2020 is an international standard published by the International Electrotechnical Commission (IEC) that defines general requirements for the Electrical Power Systems (EPS) in nuclear power plants (NPPs). This standard covers the design, architecture, operation, and maintenance of both interruptible and uninterruptible electrical power systems, including those that supply instrumentation and control (I&C) systems critical to nuclear safety. The document aligns with IEC 61513 to ensure comprehensive, safety-driven, and coherent specifications based on plant safety goals.

IEC 63046:2020 establishes high-level specifications to support reactor systems important to safety and enables electrical energy production that aids in providing the transmission grid with active and reactive power, as well as electromechanical inertia. It serves as a framework for nuclear utilities, designers, and engineers involved in the planning, implementation, and management of EPS architectures in both new and existing nuclear power plants.

Key Topics

• Scope and Application Focuses on overall EPS life cycle including design, verification, operation, and maintenance applicable for new and pre-existing NPPs.

• Safety Requirements Emphasizes the implementation of Defence in Depth, Single Failure Criterion, management of Common Cause Failures, and measures to handle Loss of Off-site Power (LOOP) and Station Black Out (SBO) events.

• Architectural Design Provides guidance for EPS architecture that supports interruption-free power supply systems, classification of systems per safety importance, and probabilistic safety requirements.

• Electrical & Functional Requirements Specifies the requirements coordinated with electrical grid operators, mitigation of electrical disturbances, and performance criteria to ensure system reliability.

• Maintenance and Quality Assurance Details maintenance considerations integrated into EPS design and outlines quality assurance plans, verification methods, and configuration management to uphold system integrity.

• Sub-system Specifications Covers detailed technical requirements for AC interruptible and AC/DC uninterruptible power supply subsystems, earthing, and coordination with external power grids.

• Verification and Testing Describes the verification process of EPS architectures, including the use of computerized modeling tools and system testing to validate performance against standards.

• Integration and Commissioning Addresses requirements for overall system integration into the plant infrastructure and documentation needed during commissioning.

Applications

• Nuclear Power Plant Design Ensures that EPS designs meet stringent safety and operational demands, enabling safe reactor operation by minimizing power interruptions affecting critical safety systems.

• Electrical System Engineering Guides engineers in designing, evaluating, and implementing robust and reliable EPS architectures that comply with international safety standards.

• Maintenance and Operations Management Assists maintenance teams in planning and conducting operations with a safety-first approach, preserving the integrity and continuous performance of EPS.

• Grid Coordination and Energy Production Facilitates interactions between the NPP's electrical system and external transmission grids, supporting grid stability through reactive power control and inertia contribution.

• Regulatory Compliance and Licensing Provides a reference framework for regulatory bodies and plant operators to assess conformance with Nuclear Safety requirements.

Related Standards

• IEC 61513 – Nuclear power plants – Instrumentation and control systems – General requirements for systems important to safety Complements IEC 63046 by focusing on I&C systems and their interactions with the EPS.

• IAEA Safety Guide SSG-34 – Design of electrical power systems for nuclear power plants Offers detailed recommendations for preferred power supply design, which IEC 63046 adopts and references.

• IEC 61508 – Functional safety of electrical/electronic/programmable electronic safety-related systems Provides foundational approaches for safety lifecycle and system integrity applicable across nuclear EPS components.

• IEEE 379 – Criteria for the design of nuclear power generating station electrical systems Addresses electrical design criteria aligning with the safety considerations highlighted in IEC 63046.

Keywords

Nuclear power plants, Electrical power system, IEC 63046, Safety requirements, Power system architecture, Interruptible power supply, Uninterruptible power supply, Reactor safety, Station Black Out, Loss of Off-site Power, Electrical disturbances, Maintenance, Quality assurance, Grid coordination, Instrumentation and control systems, Nuclear safety standards.