ElaadNL investigates power quality when electric vehicles are charging


ElaadNL is a knowledge and innovation centre with the aim of successfully integrating electric vehicles and charging infrastructure with the electricity grid. Some of the main research and testing topics are smart charging, cyber security and also power quality. In the area of power quality, ElaadNL investigates  the impact on the grid voltage quality when electric vehicles are charging. For its field measurements, ElaadNL uses the PQube, supplied by CN Rood. We spoke to Thijs van Wijk, test lab manager at ElaadNL, about power quality and the cooperation with CN Rood.


The urgency of researching power quality

ElaadNL is currently doing a lot of research into power quality and its impact. Research that is sorely needed according to Thijs van Wijk. “We are investigating the impact on the power quality when charging electric vehicles. We do this by testing vehicles and DC chargers in our lab, where we can measure any disturbances in a controlled environment, and by carrying out field studies to learn about the impact on the grids. This information is used for in-depth research into the specific effects of charging electric vehicles, such as the so-called supraharmonic disturbances. These disturbances are in a frequency range for which there are no emission standards (2-150kHz) and therefore no limits have been set yet. There is also much uncertainty about the impact of such disturbances on equipment and how they move through the grids. With our research, we are contributing to the development of knowledge on this subject, which in turn will contribute to the development of new standards in this area.”


The supraharmonic disturbances cause serious issues

Research and regulation is needed to solve and prevent the problems. Thijs van Wijk: “The supraharmonic disturbances that we see can lead to charging problems, problems with energy measurement or cause strange behaviour of other equipment, such as buzzing induction cookers. In addition, it can lead to accelerated ageing of components in the electricity grid, but also of all connected electronic equipment. Research shows that the disturbances are often absorbed by other devices. Here they cause heat gain, and thus perhaps faster ageing of the device.”


Measuring voltages and currents with a grid emulator

In the ElaadNL test lab, power quality is measured very accurately and in a controlled manner using a grid emulator. Thijs van Wijk: “With a grid emulator we create a clean electricity grid. While testing the charging process, which involves charging at different speeds, we use special measuring equipment to determine whether the device under test is causing any disturbances. The voltages and currents are measured up to one million times per second, which provides a very detailed picture. The grid emulator is also used to create a disturbed grid. This allows us to analyse how an electric vehicle or a DC charger reacts to the disturbance or whether the device is immune.”



Powerside PQube travel for field measurements

ElaadNL also investigates the impact of electric vehicle charging on the grids by means of field measurements. Thijs van Wijk: “For long-term measurements, ElaadNL has installed 5 PQubes travel from CN Rood at various charging stations. The relative compactness, robustness and the connection possibilities make it an ideal device for semi-permanent measuring set-ups at cramped locations, such as in a distribution cabinet or even in a charging station. And most importantly: the PQube can measure voltage disturbances in the supraharmonic range and produces a daily report, which we receive automatically in the mail every day. This way, we can easily gather data over a longer period of time, which can then be used for research. For instance, research into the visibility of certain trends.”


Very satisfied with CN Rood’s service

Thijs van Wijk is very satisfied with CN Rood’s service. “Both during the purchase and the commissioning, ElaadNL benefited greatly from the support provided by CN Rood. The PQube travel is a perfect mobile measuring device which we also use gratefully. CN Rood tested and configured the PQube travels and delivered them to us, so we could start using them quickly. CN Rood was also readily available for support!”


About ElaadNL

ElaadNL tests the charging of all kinds of electric vehicles, from passenger cars to electric buses and trucks and the associated charging infrastructure.

We do this in the Elaad Testlab in Arnhem, a meeting place for new models and innovations in the field of charging electric vehicles and research into the interaction with the underlying power grid.

Producers of electric cars, buses, trucks and other forms of electric mobility and of all matching charging infrastructure and ICT communication services are welcome in our open test lab. Together we can improve products and services to enable a smooth transition to smart and sustainable charging of electric vehicles.