Iec 6193612021 Link -

IEC 61936-1:2021 provides updated international requirements for the design and installation of electrical power systems exceeding 1 kV AC and 1.5 kV DC, featuring restructured clauses for protection and new guidelines for safe working procedures. This third edition improves clarity on maintenance distinctions and expands requirements for gas-insulated switchgear (GIS). Purchase the full standard directly from the IEC Webstore .   IEC 61936-1 2021 - High Voltage Power Installations AC Safety

Since there is no academic "paper" written by a single author regarding this specific standard (as it is a technical standard published by the International Electrotechnical Commission), I have developed a comprehensive technical overview paper below. This document is structured to analyze the standard, its scope, and its critical implications for electrical safety and infrastructure design.

Technical Analysis: IEC 61936-1:2021 Standard for Common Rules for the Design and Erection of Electrical Power Installations Date: October 2023 Subject: Power Systems Engineering, Safety Standards, Infrastructure Design

Abstract IEC 61936-1:2021 is the cornerstone international standard governing the design and erection of AC electrical power installations with nominal voltages exceeding 1 kV. This paper analyzes the technical framework provided by the standard, focusing on its updated safety philosophies, insulation coordination requirements, and structural design criteria. It explores how the 2021 revision modernizes guidelines for substations and switchgear to accommodate evolving grid technologies, including the integration of renewable energy sources and digital monitoring systems. iec 6193612021 link

1. Introduction The safety and reliability of high-voltage power systems are paramount for modern society. IEC 61936-1:2021 provides the "common rules" for the design and erection of electrical power installations, serving as the primary reference for engineers, utilities, and regulators. This standard applies to power installations with AC voltages above 1 kV up to 110 kV (with guidance applicable up to 220 kV and beyond). It replaced the 2014 edition (IEC 61936-1:2014), introducing necessary updates to reflect advancements in switchgear technology, insulation materials, and safety protocols. 2. Scope and Objectives The primary objective of IEC 61936-1:2021 is to ensure that power installations are designed and built to provide adequate safety for personnel and reliable operation under normal and fault conditions. Key areas covered include:

Insulation Coordination: Rules for clearances and creepage distances. Erection Guidelines: Structural integrity of supports and busbars. Safety Measures: Protection against electric shock, fire, and explosion. Documentation: Requirements for layout plans, diagrams, and maintenance records.

3. Key Technical Updates in the 2021 Edition The 2021 revision introduced several significant technical shifts compared to the 2014 version: 3.1 Insulation Coordination and Clearances The standard refines the calculation of minimum air clearances. It emphasizes the relationship between the Rated Lightning Impulse Withstand Voltage (LIWV) and the Rated Power Frequency Withstand Voltage . The 2021 edition provides updated tables for phase-to-earth, phase-to-phase, and phase-to-structure clearances, ensuring designs can withstand transient overvoltages more effectively. 3.2 Earthing (Grounding) Systems IEC 61936-1:2021 works in close conjunction with IEC 61936-2 for earthing. The standard reinforces the requirement for Earth Potential Rise (EPR) calculations. It specifies that earthing systems must limit touch and step voltages to safe levels, explicitly accounting for fault currents from modern inverter-based resources (like solar and wind farms), which can have different fault characteristics than traditional rotating machines. 3.3 Gas-Insulated Switchgear (GIS) and SF6 Alternatives A critical update involves the handling of switchgear. With the global push to reduce SF6 (Sulfur Hexafluoride) gas due to its high Global Warming Potential (GWP), the 2021 edition adapts design rules to accommodate GIS technologies that use alternative insulation gases (e.g., fluoroketones or compressed air). This includes updated pressure vessel safety guidelines and leak detection requirements. 3.4 Temporary Protective Earthing The standard has clarified the requirements for connections for temporary protective earthing (TPE). These are the connection points where maintenance crews attach portable earthing devices to de-energize lines. The 2021 version specifies stricter guidelines on the mechanical strength and placement of these connection points to protect workers during maintenance. 4. Design and Safety Philosophies 4.1 Protection Against Electric Shock The standard mandates a multi-layered approach to safety: IEC 61936-1 2021 - High Voltage Power Installations

Barriers and Enclosures: IP ratings (Ingress Protection) are strictly defined to prevent unauthorized or accidental contact with live parts. Obstacles and Placing Out of Reach: For open-air substations, the standard defines "arm's reach" and safe working distances. Voltage Grading: The use of insulation grading to prevent surface tracking on support structures.

4.2 Fire Protection and Oil Containment For installations using oil-filled transformers and reactors, IEC 61936-1:2021 dictates:

Bunding (Containment): Oil containment pits must be sized to contain 100% of the oil volume of the largest transformer plus a safety margin for rainwater and foam used in firefighting. Separation Distance: Firewalls or spatial separation between transformers to prevent fire spread are recalculated based on thermal radiation analysis. This paper analyzes the technical framework provided by

5. Implications for Industry 5.1 Renewable Energy Integration As renewable energy plants (Solar PV, Wind) typically connect at medium to high voltages, IEC 61936-1:2021 serves as the governing standard for the on-site substations. The shift towards higher voltage DC collection systems (HVDC) is acknowledged, though the primary focus remains on AC installations. Engineers designing grid-interconnection points must strictly adhere to these guidelines to satisfy grid operators. 5.2 Digitalization and Instrument Transformers The 2021 revision aligns better with digital substations. It addresses the installation of non-conventional instrument transformers (NCITs) and electronic current/voltage sensors, which require different physical mounting and shielding considerations compared to traditional oil-paper insulated transformers. 6. Conclusion IEC 61936-1:2021 represents a vital evolution in power system standards. By modernizing insulation coordination rules and integrating safety protocols for new types of switchgear and renewable energy sources, the standard ensures that electrical infrastructure remains safe and robust. For engineers and project managers, compliance with this standard is not merely a regulatory hurdle but a fundamental engineering practice to mitigate risk, ensure longevity of assets, and protect human life.

References and Further Reading