b'14 Partner News Spring 2024EnterpriseAnalyse to optimise - EV charging AC supply (pink) and current (green), zoomed in to a50Hz mains cycleStarting the charge cycleMany charging issues arise from poor negotiation between the EV and the charger at the start of the cycle. Poor connections causing voltage drops could also cause the Andy Norrie MIET, Operations Director,charge to halt. We cant see all of this in one trace (yet), but we can see the current Quarch Technology ramping up (yellow) alongside a 6volt drop (brown) which will be due to resistive losses in the cables.As the number of electric vehicles (EVs)However, a more detailed analysis revealedAt higher charging currents we start to see on the road increases, so does thethat the charger was only drawing powersignificant losses, even in heavy copper demand for efficient and reliable chargingfrom one phase, and well below its 7.4 kWcables. Some EV charging cables are liquid infrastructure. With a variety of chargercharging capability. Why is it not drawingcooled to help dissipate the heat better.designs being introduced annually, itsmore than this? The vehicle and charger crucial to understand how well thesespecs suggest that it can charge faster,chargers perform. but that is not happening here.Performance can be gauged in terms of efficiency, reliability, or charging speed. To do this effectively, we need both comprehensive data and the tools to analyse it. Most EVs and charging stations display real-time charging rates, which are essential for billing and monitoring.Start of charge cycle: RMS voltage (brown), RMS current However, this data is often basic and not(yellow), Power Factor (purple)readily available for in-depth study.3 phase voltage capture, with current (green) being drawn only on phase 1 (pink) The Future of EV Charging analysisCase Study: Kia eNiro and Evolt Charger This study is just the tip of the iceberg. Power Factors and anomalies Many other metrics like Total Harmonic We are capturing at 8,000 samples perDistortion, Crest Factor and charging second, so a lot more information appearsefficiency can be calculated from the raw as we begin to look in more detail. Thedata captured here. The visualisation of data relationship between voltage and currentis also very useful, as it often prompts us to waveforms gives us Power Factor whichask, why does that happen? when looking is the ratio of real power (which performsat an unusual point in the trace. Its rare useful work), to apparent power (the totalfor us to capture data that answers more power flowing in the circuit). We measure aquestions than it asks!Power Factor of 0.99 which is very good. In our first test, we used a Kia eNiro and anMany charging stations are imported into Evolt charger. Being able to plug togetherHowever, we observed a consistentthe UK by operators of charging networks. the required part in a few seconds makes itdistortion in the voltage waveform. ThisIt will be important to ensure that they are easy to capture a trace. could be from the supply to the charger, ordesigned correctly and can operate on the an artefact of the charger design. grid at scale, a task that will require both At first glance, the data seemedtest equipment and specialist knowledge to unremarkable - the car charged at a steadyreview the data. 3.6 kW before shutting down.'