TE - White Papers

TE Connectivity Trend Paper /// Connectivity for Next-Generation Mobility Page 8 Connectivity for Next-Generation Mobility • Connectivity for faster high-pow- er charging • Connectivity for software-driven architectures • Reliable data connectivity in all-electric environments • Wireless data connectivity It will introduce key technical chal- lenges and requirements as well as technology solutions that are avail- able to solve them. Subsequent whitepapers will share TE Connec- tivity's technical approaches and solutions for meeting these needs. 4.1 Connectivity for High-Power Charging Faster vehicle charging will drive greater consumer acceptance of electric vehicles, especially in meg- acities which have significant space constraints. In addition, it will en- able OEMs to develop global e-car platform strategies solely driven by range capability. Fast high-power charging will also be critical for MaaS businesses that deploy large fleets of autonomous vehicles. These vehicles must be kept in service for the max- imum possible time without costly down-time for charging. Traditional e-car architectural de- sign focused on range, resulting in larger batteries for energy capaci- ty requiring longer charging time. To support city-based users, who lack private charging facilities, and longer-distance drivers who need highway-based charging, OEMs are beginning to define 500A to 650A charging systems, compared to 200A today. However, if paired with typical 50 mm 2 cables, these proposed higher power systems will lead to excessive heating. One solution would be to increase cable size. However, for 500A charging systems this would lead to prohibitively high cable weight in- creases. As a result, some OEMs are now defining 800V architectures. This would enable cables to carry a higher amount of power to achieve required charging times without be- ing excessively heavy. Thermal Management and Power Net Dimensioning Traditionally, regulators determined power ratings of terminal and con- nector designs from derating mod- elling, measuring current loads over time to test the limitations of relay and fuse technology. Ostensibly these models attempted to simulate current load peaks and their time duration. However, they were based on discrete RMS profiles, as shown in Figure 4 below, which simulated static conditions that sel- dom exist in real-life applications. Specifically, testing assumptions in- cluded longer durations of the high- est current peaks would never occur in reality, leading to a higher overall assumed power load. This practice has led to design overengineering. Combined with additional built-in safety margin to cover aging factors, this has created overly robust designs with excessive size, weights, and costs. Power-net dimensioning that includes use cas- es for high-speed charging further exacerbates this problem as fast- charging cycles of five-to 10-minutes creates loads that would be far high- er than those found in any normal electric vehicle operation. TE is driving a new approach to achieve the most realistic cable and component dimensioning for the industry's required charging per- formance. This involves creating a link between thermal and electrical models and analyzing the relation- ship of the temperature profile to the current profile in any electrical powertrain wiring. Each tiny resistor can transform electrical current into heat. As a con- sequence, it is essential to identify all components within the charging chain that is impacted and how they interact with each other. They can then create a model for each com- ponent to understand hotspots. Existing components can potentially be modified with a cooling interface, for example, to connect a passive heat sink. Active coolers, such as cooling circuits or loops, are also be- ing considered for future component design. Cooled cables, where a liq- uid coolant flows through an isolated tube inside the cable and transfers the heat into a heat exchanger, are Figure 4: Discrete RMS Profiles Used for Traditional Power Net Dimensioning

• Cover