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csi developing a test bench

Electric cars have long been more than just vehicles - they could serve as mobile power sources in the future, helping to stabilize the power grid and supply energy. The development engineers at csi are working intensively on the innovative concepts of vehicle-to-grid (V2G) and vehicle-to-home (V2H). In order to verificate the charging and discharging processes efficiently, csi has developed an advanced mobile test bench that enables the testing and verification of bidirectional charging processes on vehicles during development.

“Stand still!”
Don't worry, that's not a command, but a brief description of what your vehicles are essentially doing all day long. It’s true: our cars are generally stationary and do absolutely nothing for 23 hours a day on average. 
However, we can make something of this fact, at least with electric vehicles. In this case, we can use the electric car as an energy storage unit and feed back any energy not required from the battery into the power grid, or use it as a power source for our own home. And that is precisely what the Vehicle-to-Grid (V2G) and Vehicle-to-Home (V2H) concept are all about, on which our development engineers at csi have been working intensively. Generally speaking, a great deal of energy would accumulate if all electric cars and plug-in hybrids were to be used as mobile power sources. Indeed, so much so, that the technology could offer significant benefits in terms of stabilising the power grids and optimising energy distribution. And that would then pay off – for everyone: power generators and consumers due to greater security of supply, but also for electric vehicle owners, who could then earn money by feeding electricity into the grid in the event of energy shortages, or drawing electricity form the grid at times of overcapacity. Sounds good, doesn't it? This is also the view of the "German National Charging Infrastructure Control Centre", which operates under the umbrella of the federally-owned NOW GmbH. At the start of the year, it presented a roadmap for bi-directional charging, outlining recommended actions for politicians, businesses and local authorities. If everything runs according to plan, electric cars will be able to be used as power grid buffers from 2028.

 

Attention – here's the full download!
For V2G, V2H and all conceivable future V2X applications to work, however, both the high-voltage batteries and the control unit software of the on-board chargers must be designed for this purpose. That's why bi-directional charging is a very hot topic for all major car manufacturers. And discharging too, believe it or not. Up to now, discharging the battery meant running it empty. That’s just super! Not as in Super-Plus petrol, but rather as in super elaborate in terms of time and personnel.

However, as we are generally against ultra-complicated and time-consuming solutions at csi, our Electric and Electronic department simply developed an innovative test bench capable of simulating the charging and discharging processes of electric vehicles, and thus obviating the annoying need to run the battery empty. And when we do something, we do it right. That's why the csi test bench is capable of taking into account the different charging standards stipulated by different countries, and thus can be used universally. We are able to test the control unit software of the on-board chargers for plug-in hybrid vehicles (PHEVs) and electric vehicles (EVs), which are responsible for charging and discharging functions – to the...."drum roll please"...latest standard ISO 15118-20!

Reporting for delivery
We have been supporting various automotive manufacturers and start-ups with our test bench in Gaimersheim for 2.5 years, and have also completed reliable test discharges as well. Word then got around, which explains why we received an enquiry at the start of 2023 from a very renowned OEM from the automotive sector, asking whether we would be able to develop a customised test bench for their specific requirements and sell it to them. We hadn't done something like that before, but it is precisely challenges like these that really excite us! A crucial point with this project was the fact that we would not be the ones operating the test bench – it was to be operated by our customer.  To ensure that this would be possible without hours of instructions and long manuals, it was crucial that the Human Machine Interface (HMI) was designed to be as user-friendly as possible and achieve the highest possible level of automation. At the same time, the customer needed to be able to adapt the test bench to their requirements with regular software updates. That worked so well that we are currently completing the second test bench for this very customer. Even though we designed the first test bench as a mobile, very compact unit on heavy-duty castors, which could be relatively easily used at different and changing locations, the customer wanted to further increase flexibility and capacity with a second test bench. 

This won't do any harm, as you are undoubtedly aware of the fact that bi-directional charging is an issue that we will be discussing more frequently in future. It'll be worth it.

Let us know if you have a really exciting issue on the agenda and need an outside perspective. After all, we are no longer just rooted in the automotive world. And we are at least as flexible as our test benches. Put us to the test!

Markus Geiger

Markus Geiger

Head of E/E