Enabling High Power Charging with Advanced Thermal Modelling

TETE Connectivity (TE) views connectivity technology as a key enabler of the evolution towards next-generation mobility.

Next-generation vehicles will increasingly contain functions for autonomous driving controlled by software hosted on central processing units that are maintained via over-the-air updates. These service-oriented architectures and the underlying data connectivity layer will increasingly take precedence in the overall physical architectural design.

In the area of electric powertrain design, range, fuel consumption, the efficiency of the electric systems and credible charging times will be primary considerations. In this respect, one key area of innovation is thermal management – enabling lighter and less bulky connector component design that can support high-power charging necessary for all types of consumers to truly embrace electromobility.

The aim for high-power charging is to charge a 300 km range in fewer than 10 minutes, but the related thermal loads would be far higher than found in any normal electric vehicle operation.

Thermal Management and Power Net Dimensioning

Traditionally, regulators determined power ratings of terminal and connector designs from derating modelling, 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 root mean square (RMS) profiles, as shown below, which simulated static conditions that seldom exist in real-life applications. 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.

TE Connectivity is driving a new approach to achieve the most realistic wire and component dimensioning for the industry’s required charging performance. This involves creating a link between thermal and electrical models and analysing the relationship of the current profile to the temperature profile in any electrical powertrain wiring.

Each tiny resistor transforms electrical current into heat. As a consequence, it is essential to identify all components within the charging chain that are impacted and how they interact with each other. A thermal model for each component to understand hotspots can then be created.

TE Connectivity is actively researching this type of thermal modelling for its power distribution portfolio in order to support heat dissipation requirements for next-generation high-power charging capable architectures. In addition, TE closely works with ZVEI (German Electrical and Electronic Manufacturers’ Association), an industry-wide initiativeto develop a harmonised simulation model.

TE Connectivity will be exhibiting at The Battery Show Europe and Electric & Hybrid Vehicle Technology Expo Europe at stand 940.