IEC 61851-24:2023

Overview

IEC 61851-24:2023 is an international standard developed by the International Electrotechnical Commission (IEC) that defines the digital communication protocols for conductive DC charging systems between electric vehicle (EV) supply equipment and electric vehicles. This standard specifically focuses on the control of DC charging within conductive charging systems, accommodating rated supply voltages up to 1,000 V AC or 1,500 V DC, and a rated output voltage up to 1,500 V DC. It operates in conjunction with IEC 61851-23 and applies to charging mode 4, enabling efficient and safe power transfer.

This second edition updates key technical aspects of the standard, aligning Annex A and B with the latest IEC 61851-23:2023 revisions, enhancing compatibility, reliability, and interoperability of DC charging systems. Key highlights focus on digital communication architecture, control processes, and exchanged information parameters essential for managing DC charging operations.

Key Topics

• Scope and Application
  The standard addresses digital communication between DC EV supply equipment and EVs, ensuring seamless control of conductive DC power transfer. It supports digital communication for three defined system types (A, B, and C) with detailed protocols in the annexes.

• Digital Communication Architecture
  IEC 61851-24 specifies a layered digital communication framework, including physical and data link layers primarily based on Controller Area Network (CAN) protocols. This facilitates robust, noise-resistant communication essential for precise charging control.

• Charging Control Process
  The document outlines a comprehensive control process for DC charging, including handshake sequences, parameter negotiation, safety checks, and ongoing charge monitoring to optimize performance and protect both equipment and vehicles.

• Information Exchange Parameters
  Parameters exchanged between EV and supply equipment include voltage, current levels, battery status, charging modes, and error conditions. These enable dynamic control adjustments to meet the needs of varying EV battery chemistries and capacities.

• Bi-directional Power Flow Support
  Annex A includes provisions for digital communication controlling bi-directional power flow, supporting charging and discharging operations where EVs can feed power back to the grid or local loads.

Applications

IEC 61851-24:2023 is crucial for manufacturers, system integrators, and operators involved in:

• Designing and developing DC conductive charging stations compatible with digital communication protocols to enhance smart charging capabilities.
• Implementing vehicle-side communication systems that align with international charging infrastructure for universal interoperability.
• Ensuring compliance with safety and operational requirements for high-voltage DC charging services.
• Supporting advanced features such as vehicle-to-grid (V2G) and controlled power flow management for sustainable energy integration.
• Facilitating enhanced user experience through faster, reliable charging with robust communication-supported control and monitoring.

This standard plays a pivotal role in the global EV ecosystem by enabling standardized communication for efficient, safe, and interoperable fast DC charging systems, accelerating electric mobility adoption.

Related Standards

• IEC 61851-23 – Defines requirements for DC EV supply equipment; complements IEC 61851-24 by specifying hardware and operational modes.
• IEC 61851-1 – General requirements for electric vehicle conductive charging systems, foundational for parts 23 and 24.
• ISO 15118 – Covers high-level communication protocols for vehicle-to-grid communication including digital key exchange and smart charging functionality.
• IEC 61850 – Used for communication networks and systems in substations, relevant for integrating charging stations into electrical grids.

By adhering to IEC 61851-24:2023 and related standards, stakeholders ensure interoperability, safety, and performance in modern DC conductive EV charging systems worldwide.

Keywords: IEC 61851-24, electric vehicle charging standard, DC charging communication, conductive EV charging, digital communication protocol, IEC standard, vehicle-to-grid, EVSE communication, charging control process, CAN communication, EV supply equipment.