Objectives

Metrology for electric vehicle charging systems

Objectives

The project focuses on the development of metrology capabilities for the traceable evaluation of EVCSs under realistic operating conditions.

The specific objectives are:

  1. To define representative on-site operating conditions for EVCSs in terms of local grid disturbances and local grid impedance under live grid operation. For this, dedicated measuring equipment will be developed for measuring local grid disturbances and local grid impedances up to 150 kHz. With this equipment measurements will be performed at, at least, five sites with DC chargers and five sites with AC chargers with a variety of (i) charger brands, (ii) operating modes and (iii) charging power levels.
  2. To develop traceable methods and test benches for the characterisation of EVCSs under representative operating conditions for both AC and DC charging in accordance with IEC 61851-1. For AC chargers, the characterisation will be performed at low and medium power, and for DC chargers the characterisation will be done at low, medium and high power. The characterisation involves the evaluation of (i) metering accuracy and energy transfer efficiency with a target uncertainty of 0.1 % (with respect to nominal power) and (ii) generated conducted emissions up to 150 kHz. For AC EVCSs, test benches will be developed for three-phase systems at 230 V up to 100 A and charging power levels up to 44 kW; for DC EVCSs, test benches will be developed for voltages up to 800 V, currents up to 500 A and charging power levels up to 350 kW.
  3. To develop the required metrological infrastructure for on-site verification of EVCS energy metering, in support of legal metrology and acceptance testing, with a target uncertainty of 0.5 %. This will include the development of reliable methods for EVCS energy metering evaluation based on commercially available equipment, which have been validated under representative operation conditions, including smart charging and bidirectional energy transfer.
  4. To facilitate the uptake of the technology and measurement infrastructure developed in the project by the measurement supply chain, standards developing organisations (IEC TC 69, WELMEC WG 11, OIML TC 12/p 3, EC WgMI E01349), and end users (e.g., EMN Smart Electricity Grids, EMN Clean Energy, EVCS operators, grid operators, EVCS manufacturers).