GB/Z 109-2025 Active

This document provides guidelines for the analysis of the AC and DC electrical systems of nuclear power plants. Electrical system analysis is used to demonstrate that the power supply and distribution systems can support the safe operation and shutdown of nuclear power plants, and that nuclear power plants can enter a controlled state and ultimately achieve a safe state after experiencing anticipated operational events or accidents.
This document is applicable to:
—— Verifying the design of new nuclear power plants;
—— Demonstrating the adequacy and impact of major modifications to the electrical systems of operating nuclear power plants;
—— Evaluating and determining the operational limits and constraints of operating nuclear power plants.
The relevant provisions of this document also apply to nuclear power plants in the decommissioning phase.
This document is not applicable to:
—— Digital controllers used in electrical systems (such as controllers for rectifiers, inverters, sequencers, and electrical protection devices);
—— Environmental conditions (such as temperature, humidity, etc.) and external events (such as earthquakes, floods, fires, high-energy electromagnetic pulses, etc.) that may affect equipment selection or protection requirements, excluding external events such as lightning and geomagnetic bursts;
—— Additional or special content related to independent power systems, such as the power supply used as a security measure for nuclear power plants;
—— Content related to improving the reliability of nuclear power plant electrical systems through the adoption of statistical or diversity and redundancy solutions;
—— Personal safety protection measures during the installation, maintenance, and operation of electrical systems, as well as routine personal safety requirements.
The methods or tools used in the analysis include:
—— Validated and confirmed simu