Empowering the Future: Designing Secure and Remotely Managed Electric Vehicle Chargers

Matt: Yeah, that's one of the advantages of Ventus is you wouldn't have access to actually configure that device. So, again, when we're working through that pre-sale stage, going through the engineering, and understanding exactly where you're connecting to. We build an image of that, and we create that consistency across the platform. So, the customer does not have access to that device to make any changes. That also allows our support desk to understand exactly what's going on at those destinations and provide complete support. So, while, again, if you do need to make some changes in the future, that would go through our engineering department, and we would deploy that throughout your entire portfolio, and so that you would not have access to those devices.

Dunstan: So, the EV chargers are out on the street; they're unmonitored, and there is no one standing there guarding them, so they are open to physical attacks. And the government, certainly in the UK and other countries, have recognized this. And there are mandated anti-tamper mechanisms. These can be sort of old-fashioned. Certainly in the UK, the regulations don't specify how you do it. 

One way we've done it is using an accelerometer, and it can measure not only tampering, for example if somebody takes a charger and take off the wall, and they play with it. But also, any impact of a vehicle into the charger as well, such as a maintenance function. Some people use micro switches, magnetics, or something more old-fashioned, like more like a sort of custom wire. 

The problem with electronic methods, of course, is that they're going to measure tampering whilst the actual charger's turned on. But if you use something like an accelerometer, it basically can actually measure if there's been a change to the actual charger configuration. So, if you take it off, tamper with it, and then put it back on again, unless it's put on exactly as it was installed, you might be able to spot that. But yeah, there is a mandated necessity for having some form of anti-tamper.

Matt: We do provide dual-SIM connectivity. We utilize the Ventus devices or the Digi devices. Again, during that design phase, we would choose the best hardware for what you're looking to actually connect out there, and we do that with seamless failover between the carriers. So, if we're working in the U.S. here, we would use the Verizon, AT&T Mobile, and we would choose the best on two carriers for that location, and embed those within, for that seamless connectivity between them.

Bob: Yes, if you're already building power and control cabinets, we can help you use some of the parts and pieces, and then develop a compliant rapid charger. I think Dunstan would say too; our products would not be compliant out of the box. You would need to go and get certification yourself, on the finished rapid charger.

Dunstan: Yes, the fastest way to market is to use approved inverter modules, which connect over CAN bus, to the Digi ConnectCore® 93 module or whichever particular SOM and motherboard you're using. You can use CAN to control the inverters, and then you use the EEL board to control the AC side of it and the Versinetic REMORA board to do the power communication so that supports the 50118 and DIN standards.

Just picking up one of the questions we had earlier about Tesla charging standards. So, anyone, if you got a Tesla, you know that they'll work with standard DC chargers using the DIN standard, which we can support. They've got their own locked-down proprietary standards as well, which we wouldn't support. So, we can create a DC charger which will charge a Tesla fine, like any other DC charger, but obviously not like a Tesla proprietary supercharger.

Bob: Basically, there are other OTA services on the market. The difference is that ours is tuned precisely to Digi ConnectCore system-on-modules and our software stack. So, it's integrated into our stack, and it's metered directly to the ConnectCore SOM, so you can get specific information sent out. You don't have to adapt a generic over-the-air service to your specific product or your specific hardware. It's already fine-tuned and ported to the ConnectCore SOM, and gets you to market faster that way.

Chris: If you break into a charger, and you look at what you can actually attack, as I was saying, you actually have the certificates burnt into the SOM. You can't access those. You can't read them back out again. And so that gives you protection against a scammer basically trying to hack the charger and put their own app on. So, for instance, they might want to reroute you to some other payment, fake payment terminal, or whatever. But effectively, the software is locked down through this chain of trust, all the way from that certificate being burnt onto the processor, right through to the file system and the app being launched. So, that's the main protection against those sort of physical attacks.

Matt: Most EV chargers have their own proprietary software and applications. So, the customers that we're working with today have full visibility into that. Ventus is really sending that traffic data securely. We're moving that data from point A to point B, so that's flowing into the customer's application that they have, and they can view all that data there. We can also look if there's APIs, to bring that into our platform, again, for that single pane of glass.

Bob: There is actually a draft of that from August 2023, that is being prepared for EV chargers. It's part of the overall U.S. cybersecurity rules, and I think that, you know, Dunstan made a great point. There's a lot of focus on medical devices right now, but right up there with the medical devices are products that connect to the critical infrastructure. So, there will be government regulation. If you take a look, that is in process right now, and you can see that in the U.S. It's driven by the National Institute of Standards and Technology, or NIST. So, the draft is there. There's process where we get feedback so I would expect something to actually pass within the next one to three years from now.

Dunstan: There are similarities and commonalities, and there are differences. The U.S. is different from, say, Europe and Australia, Asia, Middle East, and Africa, with the NACS standard. So, obviously, there's been this large amount of government infrastructure support put in, and that's only available to open networks fast chargers. So, it's obviously telling things you already know, like Tesla opening up their standard, to allow other vendors to use their chargers. But, I mean, the rest of the world, there's different standards in China, but certainly Europe, Australia, we're using CCS, CCS2, and gradually, what we're seeing is that countries typically are starting with a sort of dumb charger, fairly unregulated sort of industry, but they're rapidly moving towards secure and smart charging, because of issues around power grid stability. And there are still quite a few countries that have very low EV take-up, where you can use dumb chargers. But Australia is a good example, a place where we've got customers. It's a high-income, advanced country, but they've been quite late to the party in terms of EVs.

At the moment, you can still install dumb chargers, but, again, the government's now going through the sorts of regulations that the U.S. and Europe went through previously. So that's basically set to change going forward. One of the presentations I've done over the last two years has been around comparing 10 different countries, and what they're doing. So, I can provide more information on that offline.

There was a question about whether we could do two, about delta 61851 modules. Basically yes, we could do a design for two CCS guns on that, effectively in the way that we would use a Digi module, with dual Remora boards for the powerline communications. I'm not familiar with the exact modules you're using, but they're normally using CAN bus to control, which you can control from the module. But yeah, it's not like an off-the-shelf thing. This is something that we'd have to get involved with some design work with, to do that for you.

Matt: So, TLS, Transport Layer Security, or OCPP, which would be in your charger — a lot of customers choose to utilize that over the Internet. Obviously, the Internet has its own risks, so a lot of our customers utilize our private network. We're PCI-compliant; we could send that traffic back to the payment card processors, so it's just an additional level of security. I don't think there's enough that you could do around security, in regards to your communication and your EV charger, so the more that you could add layers to that, the better that application.

Matt: So, obviously, cellular doesn't work everywhere. It's great where it does. We do have locations where there are connectivity issues, and we see that. We provide full broadband services as well, so if the customer needs dedicated Internet access, broadband, fiber, whatever is needed, Ventus provides the full suite of services, again, on that single invoice, providing that cellular connectivity and broadband services if needed.

Dunstan: Chargers can be designed around lots of different microprocessors. So, there's been a general move on the home charger, the basic end of the market, to move to a sort of microcontroller-type architecture, just because it's very price-competitive. However, public chargers, and DC chargers in particular, are pretty much all based around Linux, because they've usually got, like DC charge, you’ve usually got screens, you've got more sophisticated user interfaces. But, in terms of actual performance, with 15118s, on the Plug and Charge standard, there are some time-critical aspects to it, in terms of turning around the certificate exchange that we were talking about earlier. So, whilst the charger, like, a dumb charger, and what you might call a first-generation smart charger, isn't particularly demanding on CPU usage. It can work with a low-end source application processor, like an i.MX 6UL. Once you get into 15118, and Plug and Charge in particular, that does have more of a requirement on it, in terms of how fast it operates. So, none of the aspects of EV charging itself require sophisticated, super-fast processors, but it's more the aspects that we've been talking about on this seminar, around security, but also things like user interface, that will probably determine what sort of micro, or hardware architecture you pick.

Dunstan: Certainly, in the UK, if you're under 22 kilowatts — and this again applies internationally — basically, you don't typically have a payment terminal. A lot of these sorts of chargers, where they're shared chargers, but say it's a residential, it's a block of flats, typically, you'd use an RFID card. So, something like a MIFARE card. And certainly, like that LINKRAY product that I mentioned earlier allows us to whitelist RFID cards. Again, it's using OCPP, which is secure, to talk to the chargers, but it's not requiring necessarily to, a cloud connection. This wouldn't be suitable for handling payment processes, as you allude to in your question.