ISO 5474-4:2025

Overview

ISO 5474-4:2025 - "Electrically propelled road vehicles - Part 4: Magnetic field wireless power transfer (MF‑WPT)" specifies functional and safety requirements for on‑board vehicle equipment that enables magnetic field wireless power transfer between supply devices and electric vehicles (EV). Intended for passenger cars and light commercial vehicles, the standard covers safety, power transfer performance, ground clearance, interoperability with off‑board systems, and test procedures for EV power circuits (EVPCs) implementing wireless charging.

Key Topics and Requirements

• Safety requirements: emergency shutdown, protection against electric shock, insulation coordination, thermal protection, and safeguards for people exposed to electromagnetic fields (ICNIRP guidance) including requirements to protect the functionality of cardiac implantable electronic devices (CIEDs).
• Power transfer and efficiency: rated output power, transferred power, and minimum power transfer efficiency expectations including behavior for unmatched power levels between on‑board and off‑board devices.
• Frequency and electromagnetic compatibility (EMC): specified operating frequency ranges and EMC limits plus testing procedures to ensure compliance with emissions and immunity requirements.
• Geometrical operating space & ground clearance: defined alignment, alignment tolerance area, centre alignment point, and required ground clearance parameters to guarantee reliable MF‑WPT operation.
• Functionality & interoperability: requirements to ensure EV devices operate reliably with supply devices from different manufacturers and under varied environmental conditions.
• Test procedures and conformance: detailed test setups and procedures for MF‑WPT power transfer; normative annexes include reference supply power circuits for EVPCs with rated output power ≤ 3.7 kW and ≤ 11.1 kW and informative annexes on alternative implementations and exposure conformance.

Practical Applications and Who Uses It

ISO 5474-4:2025 is essential for:

• Automotive OEMs and EV system integrators implementing wireless charging systems.
• Wireless charging equipment manufacturers (EV secondary/EVPC design).
• Component suppliers (coils, power electronics, control and communication modules).
• Test laboratories and certification bodies validating MF‑WPT safety, EMC and interoperability.
• Regulators and public charging infrastructure planners assessing vehicle compatibility and safety. Practical uses include designing compliant EV on‑board chargers for stationary wireless charging pads, specifying vehicle‑side requirements for supplier contracts, and performing conformity testing and safety assessments.

Related Standards

• IEC 61980‑1 / ‑2 / ‑3 (WPT system general, communication, MF‑WPT specifics)
• IEC 61980‑4 / ‑5 / ‑6 (supply device power levels and dynamic WPT - referenced for scope exclusions)
• ISO 5474‑1 (general conductive power transfer requirements)
• ISO 6469‑3 (electrical safety for EVs)
• ISO 20653 (IP protection)
• ICNIRP guidelines (human exposure to low‑frequency fields)

Keywords: ISO 5474-4:2025, MF‑WPT, magnetic field wireless power transfer, wireless charging, EV, EVPC, interoperability, power transfer efficiency, safety requirements, EMC, testing.