Charging mobile machines correctly

00:00:00: Hello everybody and welcome to a new episode of our tech podcast by Bosch RexRot.

00:00:10: My name is Robert Wieber and today we are going to talk about charging mobile machines.

00:00:16: And my guest today is Eric Engel.

00:00:17: Welcome Eric.

00:00:18: Hi Robert.

00:00:19: Please introduce yourself briefly to the listeners.

00:00:24: My name is Eric Engel.

00:00:25: I am since April 2022 in Bosch RexRot.

00:00:30: Previously I did my master thesis or my masters in mechanical engineering in AVTR-Aachen.

00:00:37: With the focus of automotive engineering.

00:00:41: During my studies I was able to get a look into the automotive sector and there are some

00:00:47: internships and working as a working student.

00:00:51: Afterwards I did my master thesis for corporate research in Bosch Central in Röningen.

00:00:59: And there I get in touch with a guy from the E-Line project from Bosch RexRot and then

00:01:05: he came to me and asked if I wanted to join as a software developer in ULM for the E-Line

00:01:12: project.

00:01:13: And now I am here.

00:01:14: Why do we need to record an episode on charging?

00:01:18: I think charging is simple.

00:01:20: Yes, so charging is an everyday task for everyone.

00:01:24: Everyone has at least one device which is battery electrified.

00:01:29: So the main difference for charging in the off-highway market is that it is a different

00:01:35: voltage level.

00:01:36: So basically we are in a range of 700 to 800 volts and due to that we have additional functions

00:01:45: or safety related functions that has to be taken into account for charging off-highway

00:01:52: machines.

00:01:53: And we have different grids in different countries and different standards and yeah.

00:01:58: So basically in the European Union we have the three phase grid with 230 volts and in

00:02:07: North America there is the 110 to 120 volt grid with one phase, pretty common.

00:02:18: But in addition we have several countries, for example, Brasilia with hybrid, I would

00:02:25: call it.

00:02:26: So you have several parts with the three phase grid from the EU and also the one phase grid

00:02:33: from North America.

00:02:35: So this is like pretty difficult for the OEMs, so for our customers.

00:02:41: Can you explain us the Bosch RexRoot product?

00:02:46: What is your charging product?

00:02:49: So our charging product is mixed between a hardware solution to enable the voltage, the

00:02:57: charging of the battery and also a software package where we enable different charging

00:03:03: standards in the market.

00:03:05: So because I was wondering because you are a software engineer, why do the team from

00:03:11: E-Line needs a software engineer?

00:03:13: Can you explain this a little more detailed?

00:03:16: So we have different forms of charging.

00:03:20: One is the AC charging, there we are limited to 22 kilowatts in power.

00:03:26: In addition we have the DC charging here, we are not limited in the power, but we have

00:03:36: to communicate with an EVSE so with a charging station.

00:03:40: So your part is to enable the communication, a proper communication?

00:03:46: This is the part of the software to enable the communication and also have some safety

00:03:53: functions enabled that the vehicle for example is not overloaded.

00:03:58: So basically this is like the interface for the customer, the communication of the limits

00:04:05: of the vehicle.

00:04:06: So for example how much current is allowed and how much voltage.

00:04:11: Why is this so difficult to develop or why is it so important to develop a product for

00:04:17: this approach?

00:04:20: So the problem here is that in the off highway market we have different use cases.

00:04:28: So if we are for example on the highway or on the road then the loading is pretty similar

00:04:37: to the automotive market.

00:04:39: So for example for tractors it is really important, but if we are in different use cases then

00:04:47: the customer uses like own charging standard I would call it.

00:04:52: So he just connects.

00:04:54: That sounds very crazy.

00:04:56: So he is connecting directly to the grid.

00:04:59: That's why we have like the challenge of the different grid forms.

00:05:03: And also you have like higher power demands for DC charging in the off highway market because

00:05:11: yeah you need more energy compared to the automotive market.

00:05:17: What are the challenges with mobile machines concerning charging?

00:05:22: Is it a topic of robustness or what are the three main challenges?

00:05:28: So the main challenges in the off highway market are firstly the robustness against mechanical

00:05:34: loads.

00:05:36: Then we have the use case that the vehicle.

00:05:40: So what is the solution?

00:05:41: What is the solution to do that?

00:05:43: The solution is that if we choose components you have to use components which are…

00:05:49: It's a sourcing topic.

00:05:50: Yeah, definitely.

00:05:52: So basically on one hand you have the components that has to be chosen wisely and also the

00:05:59: topic of the PCB layout.

00:06:01: So we are doing like a reclusive testing and for that we are taking account the additional

00:06:08: loads from the off highway market.

00:06:11: And in addition we have use cases for the off highway market where the vehicle is connected

00:06:19: to the grid for the whole time of usage.

00:06:22: So basically during operating you have like long cables which are connected to vehicle

00:06:29: to be the main power source.

00:06:32: So this vehicle for example don't have a battery.

00:06:36: For the third we have the parallel operation topic because with one onboard charger it's

00:06:43: in several use cases not possible to deliver the required power.

00:06:49: So that's why it is possible for our onboard charger to connect them in parallel.

00:06:54: That you have like four times for example the power that one onboard charger can deliver.

00:06:59: I want to go into detail to your product.

00:07:03: Can you describe the listeners' yop?

00:07:06: product? Is it a hardware component packed with software? And where is it situated in

00:07:13: this whole charging process?

00:07:15: So basically, we have two different hardware variants, one for the EU grid and the second one

00:07:24: for the American grid. And on the software side, we have two different different software

00:07:30: packages. The first one, also the main software package is the send alone variant. Here it is like

00:07:38: complete whole solution for the customer. So the communication and also all functionality is done

00:07:47: by the onboard charger. So basically, it is a pretty complex device inside. But the onboard

00:07:53: charges your product. Yeah, this is our product. The OBC. Yeah, the OBC. Yes. So the onboard

00:07:59: charger is a pretty complex component inside. But for the interface for the customer, it is a

00:08:05: pretty easy device to implement into the vehicle. So so the first one is the standalone solution

00:08:12: standalone solution, right? And the second one is a slave solution for the slave solution. The

00:08:18: loading communication is done by an different controller. So for example, the vehicle control

00:08:24: unit can do this task. And here the vehicle control unit is then doing the loading communication.

00:08:30: Okay. And the OBC is just transferring the energy. Okay, what is the demand of standalone

00:08:37: solutions? Is the demand higher than a slave solution? Yeah, so the charging topic is also for

00:08:43: the our customers a pretty new topic. Due to that, the standalone variant is more required or more

00:08:52: demanded from the market. When we talk about this standalone, the safety is a very important topic.

00:08:58: What, what requirements on safety do you have with your OBC? So for the OBC, we took the on the

00:09:07: market demanded safety standards into account during development phase. So for example, the ISO 13849.

00:09:17: So this is like functional safety on on the Charter side here. And how do you integrate this OBC

00:09:25: into the customer's system? Can you go because we are focused on the standalone solution? Can

00:09:30: you go a little bit more in details? So for OBC, we have like three main interfaces. So on the one

00:09:38: hand, we have the HV interface. Here the OBC is connected to the battery. So to the intermediate

00:09:47: circuit. The second interface is the AC connection. It is the connection to the inlet. So to the

00:09:55: interface to the loading station. And the third interface is the low voltage interface here is

00:10:02: the communication also the power supply of the PCB enabled. Yeah. And how difficult is it for

00:10:11: customers for your customers to manage this? So they choose the standalone because you manage

00:10:17: everything for them? Or why is it choose this solution? So this is like the main aspect here.

00:10:23: The problem is that the market is really dynamic. So we have for example, like the NACS standard.

00:10:32: Yeah, it's a Tesla standard. The Tesla standard, right? So this is like a whole new topic in the

00:10:38: United States and was pretty fast decision. And for example, for I think there was no decision

00:10:44: everybody said, okay, we will do like that. It was like that. Yes. Yeah, correct. And for several

00:10:50: countries, we don't have a charging standard which is communicated. So here, for example,

00:10:57: like Africa or Asia, maybe it will be CCS or NACS. And everything depends on this inlets, right?

00:11:05: So yeah, the communication is somehow connected to the inlets. So we are also able to support

00:11:12: different inlets in the OBC. So this is done by parentization. So you have like three aspects

00:11:20: for every inlet, which is different. You have the connection to the LEDs, the actuation of the

00:11:26: locking and also the temperature sensors has to be somehow different supported for every inlet.

00:11:34: What does NACS now mean for your software and for your hardware?

00:11:40: So the NACS is basically a different charging communication standard. So here, the OBC has

00:11:48: to do the right handshakes to enable this. So you have to adapt the software. On the other hand,

00:11:56: it is for example, for the NACS, there is also then the Tesla inlet supported. And for that,

00:12:03: like I said, you have to take three problems. So for example, the LEDs, the actuator and the

00:12:12: temperature sensor has to be enabled in the OBC. So it's a new job for you, a new task?

00:12:17: It's a new task, yes. It's a new software task, right? Yeah. So it's a very complex market you

00:12:23: mentioned. Why did you choose to go in this market as a Bosch Rex road? Because it's very

00:12:30: complicated. If somebody changes something, you have to change the software. What is so

00:12:34: special and so interesting at the market? Yeah, so basically, we are working on that because

00:12:41: for a battery electrified vehicle, it is an important component. And we are as the

00:12:47: E-Line team are selling also system architecture or system solutions. That's why it's an important

00:12:55: part of it with our experience in the off highway market. And also with the Bosch knowledge,

00:13:03: we are able to offer a solution for this problem. What's next? What's coming next?

00:13:09: What's your next task? What are your next jobs to do, Eric? So currently, our main focus is on the

00:13:17: start of production on the off the shelf start of production of the OBC and DC-DC.

00:13:24: This contains much work in documentation, for example. Also, one major task currently is to

00:13:33: check the market. There's a new Tesla. Yeah, for example, if there is a new Tesla to the standard

00:13:39: or something like that, to offer here also solutions to the customer to be state of the

00:13:45: art with the onboard charger. And also we are working to enable further inlets. So basically,

00:13:53: to enlarge our portfolio of the inlets. This is also a main task. Yeah, we wish you all the best.

00:13:59: Thank you, Eric. It was a pleasure. Thank you, Robert. Yeah.

00:14:11: [ Silence ]