Vehicle Technologies in Transition
JAE and Yazaki are two companies on the forefront of automotive innovation. We talk to experts from both about the challenges of autonomous and electric vehicles.
By Gale Morrison and Connector Supplier vehicle
Technology is dramatically changing every aspect of modern car design and function. Electric drive trains are undergoing dramatic refinements and reaching full viability. From sophisticated safety systems to adaptive cruise control, lane keeping, and automatic braking, elements of autonomy are becoming part of standard vehicle operations. Fully autonomous vehicles are on the horizon and the implementation of 5G infrastructure will hasten their arrival. These developments are made possible by great advances in automotive interconnect technologies.
We talked with two companies that are innovating connectivity products for the automotive market to find out what challenges the industry faces as it moves ever closer to full electrification and, eventually, full automation. Jussi Takaneva is a general manager at Japan Aviation Electronics (JAE), a leading supplier of automotive electronics and high-powered connectivity products for electric vehicle charging. Eric Varton is the chief engineer of advanced development for core engineering at Yazaki, a leader in automotive electronics wiring.
Automotive systems are involving more data capture and storage and more software expertise than ever. What challenges does that bring for your company and your customers?
Takaneva: More data capture and storage means, among other things, higher transmission speeds and more connectors to various sensors. This, of course, leads to the need for more innovative products and systems. For the world of passive connectors and cable harnesses, the impact of software expertise is not always directly linked. Of course, especially in area of autonomous driving and related software and electronics, the customer base providing these solutions is much wider and innovations are coming from other industries as well, including software-based providers.
Varton: One of the biggest challenges is that we want to enable failover rather than failsafe. We also want to enable or support this huge reliance on data within the safety systems. That’s nearly as important, if not more important, than moving electrons around for electric distribution.
How is your company innovating as we enter a new phase of platform engineering for electric vehicles?
Takaneva: For the platform engineering developments, it is important to be involved in the developments from the early beginning. We have to support our customers and provide scalable and future-proof products, which will, of course, typically end up being used for a longer period and with higher volumes. Especially when platforms are shared across various regions or even OEMs, it is important and sometimes challenging to find the balance between all various requirements. JAE is especially focused on providing products for various battery management systems (BMS) and innovating in the area of high-voltage applications.
Varton: In the electrical distribution system (EDS) of a car, there is a wholesale change in requirements that come with the higher current and higher voltages associated with faster charging. That means higher power, since power is a product of current times voltage, and as more power is required, that means that increased current requires us to increase the size of the wire. But you can’t just change the material size without effecting equilibrium of the entire system. In a hybrid power train, that might mean larger-gauge wire and more power, and then you are effecting weight. But if you change to aluminum, that requires completely different connector systems.
In a perfect world, we’d have one global standard: same interface, same geometries. Of course, that is not the world we live in. We have different voltages, different frequencies, different legislative and regulatory bodies like UL, and so many more.
What do we see next on the connector and cabling roadmap for faster electric vehicle charging? How do you adjust for geographical differences?
Takaneva: The world of electric vehicle charging products is rapidly changing and continuing to evolve. The requirements for faster charging speeds and higher power bring new challenges involving weight, cost, cooling, etc. Recent developments take the charging power well above the megawatt level, and this will truly take the current charging infrastructure to its limits. JAE is active in various development groups and standards, such as CHAdeMO and CharIN, which extend across regions to help surmount geographical differences. The other trend, of course, is to bring the customer an affordable and purposeful charging solution. These systems include products like home DC charging, vehicle-to-grid (V2G) systems, and innovative automatic and wireless charging solutions.
The volume of sensors and overall electronic content employed in vehicles is ever increasing. How does the harness design keep up?
Varton: With electrification and advanced driver-assistance systems (ADAS), and eventually autonomous systems, we just see more density. Instead of two connectors with 20 pins, you might have two connectors with 50 pins. OEMs want fewer power connections and more data connections. A lot of the EDS wiring connectors are driven by the device side. But remember, the fewer interconnections between the harness, the greater reliability. If you have 60–100 circuits, adding connectors of multiple sizes, and maybe even data and power together, that drives a whole new list of potential issues. And, as always, the overall reliability of the system is impacted by the number of times the wire has to pass through a connector. A lot of manufacturers are looking at limiting the number of connectors. Then you have to accommodate that a typical mid-size vehicle body harness is going to weigh in at 75 or 100 pounds, and a human operator has to put that in the vehicle. How do you, in your architecture, make sure that weight does not increase without manufacturing impacts or impacts to reliability? OEMs are asking, how do I make it lighter? Vehicle architectures are continually being refined and changing to try and reduce wiring but, as you integrate, you introduce a single point of failure for multiple systems.
Fully battery-electric vehicles are bringing new safety and reliability challenges for wiring and connector makers. How is your company solving these issues?
Takaneva: There is a change in the test requirements to improve safety and reliability. Higher currents, voltages, and temperatures, especially in tough environments where there is vibration, humidity, and high or low temperatures, bring new challenges. In the area of electric vehicle charging — products the end-user is physically touching — the safety requirements are very important. New and robust materials and innovative serviceability options are some of the features JAE is offering to customers. Our innovative electric vehicle charging products in the KW Series take these issues into account.
Varton: In a fully battery-electric vehicle, the powertrain’s electrical system has battery stores and the motor and an inverter between the motor and battery. You need to move large amounts of power safely between the motor and battery. That can be 400, 500, 600 volts or, in a bus or commercial vehicle, 800 or 1,000 volts. The greater current requirement, the larger the wire has to be. Most electronics modules in a car can’t handle high voltage. The majority of control systems are operating down around 12V. Small semiconductor regulators take that even further down to 5V. Then there is no danger to driver or occupants if there is a short or contact. The industry is certainly coalescing around 48V, the highest multiple of 12V that’s less than 60V. At 60V, there are risks from short circuits to drivers and passengers.
You also introduce other problems with higher volts. At 48V and higher, you ionize the air between the contacts. Should you create an arcing event, there’ll be damage to electrical systems, and these can be very expensive components. We see the need for newer approaches there. Say there is a short next to insulation or the carpeting in the cabin — that could create a fire. We need to make sure we are protecting for arc faults and direct shorts and providing for isolation between the higher voltage areas and the rest of the system.
These different architectures drive the need for new components. That might mean larger terminal sizes, or that might mean you terminate to different materials. One small change to the system can have wide-ranging effects throughout the system and vehicle. With lithium-ion battery packs, we’ve seen a fire can start two days later in the collision lot. There are some precautions we haven’t had to address in the past that we need to address now. It’s just very important to understand how energy is flowing. What is the state of our battery and battery charge? How do we tell the driver his range? We have to do a lot of calculation. More precision current sensing is a focus for us right now. Battery management computers and algorithms, putting energy into the battery from a charging station and doing that into hundreds of thousands of cells at once. At those interconnects, we can do precision current sensing and thermal sensing.
As we get closer to battery electric vehicles, the move to electrification changes materials, connectors, manufacturing strategies, and design approaches. You need to start your design digitally in new ways so you can reuse and capture what you have engineered and let it drive or inform future designs.