EV CHARGING ISSUES Innovation and Operations Centre, it has also developed technologies that provide direct insight into the vehicle side of charging. Bishop explains, “The vehicle telematics unit we developed sits in the vehicle, connecting to the CANbus that runs the powertrain management, battery management systems and chassis management systems, which allows us to see the whole charging experience on the vehicle side, rather than from the charger side. Particularly, how the BMS within the battery is interacting with the charger.” Being able to monitor cell-level voltages in the battery pack has revealed some interesting findings, he says. “We were looking at an issue recently, whereby [a vehicle] ABOVE: On-the-ground feedback from charging networks is vital to refine systems BELOW: Ford’s rapid software updates tackle incompatibilities charged initially at a high rate, 150-plus kilowatts, and then just nose-dived. Everyone was blaming the charger, and what we could see was that the battery temperature sensors internally were peaking at 50°C, which is the absolute limit for internal cell temperatures in the pack. We could see the temperature slowly falling as the cooling system became effective, and then it resumed the charge.” Gridserve’s data collection plays a key role in the development of vehicle chargers, particularly for OEMs. Bishop’s team provides manufacturers with detailed reports to support their efforts. Gridserve’s research hub also includes an in-house test facility, used to evaluate new chargers, test software updates and replicate identified issues. “We get vehicles from different manufacturers in here and try to reproduce some of the problems we’ve seen on the network because we can hang test equipment easily here,” Bishop explains. A range of vehicle types, charging scenarios and power levels can be assessed. Gridserve can also inject fault conditions to see how the charger responds when a vehicle doesn’t behave as expected. The company runs an extensive range of tests that examine not only how the charger interacts with the vehicle, but also the charger’s impact on the power grid. “Chargers are not particularly grid-friendly items because they change a lot of harmonics that get transferred onto the grid supply,” Bishop comments. “They also generate adverse power factors. Looking at those and the overall conversion efficiency and things like that is all part of the evaluation process for new products.” What happens at a Testival? Much of the industry’s collaboration happens at Testivals – specialized events organized by the Charging Interface Initiative (CharIN). So what actually happens at a Testival? Held several times a year in different regions, these events bring together key players from across the EV ecosystem and provide the space, equipment and structure needed to run interoperability and performance tests. CharIN supplies detailed test plans to guide participants through various testing scenarios, helping to ensure consistency and meaningful outcomes. Events for 2025 are scheduled in Europe and North America, where engineers will run a range of tests, including: Communication protocols: Evaluating the implementation of communication protocols, such as ISO 15118, which are critical to a seamless charging experience; End-to-end plug-and-charge testing: Analyzing the functionality of plug-and-charge, including the back-end systems, using valid and expired certificates to assess security and interoperability; Smart charging: Exploring features such as charging schedules that optimize charging based on various factors; Bidirectional power transfer: Assessing the ability of bidirectional power transfer to allow vehicles to draw power from the grid and return power when needed; Security testing: Scrutinizing security measures, including encryption and authentication, to protect charging transactions; Safety testing: Evaluating safety features, such as plug locking mechanisms, in various scenarios to ensure a safe and reliable charging experience for users. 52 JUNE 2025 www.AutomotiveTestingTechnologyInternational.com
Automotive Testing Technology International June 2025: Page 52
