The advancement of artificial intelligence and communication technologies has driven innovation of the automotive industry. Riding on a wave of connected, autonomous, shared, and electronic qualities, the characteristics of electric vehicles (EV) and autonomous vehicles are fused to shape future cars. This trend not only shifts focus to road safety and pedestrian safety, but also takes into account environmental protection and the energy-saving goal to achieve sustainability.
On May 30th, DEKRA iST was invited to attend 2024 Future Car Technology Forum held by EETimes at the HNBK International Convention Center. Wangchu Chen, Director of the High-Power Engineering Department of DEKRA iST, delivered a speech on "Exploring the New Trend and Challenge of EV Powertrain and Self-driving Vehicle on Reliability Validation by International Standards." In addition to the technology development in the automotive industry and the differences in the new edition of the commonly used international standard ISO 16750 for road vehicles, he also pointed out the issues usually faced by customers, as well as the potent solutions that DEKRA iST proposes to all kinds of bottlenecks when undergoing testing for automotive components.
History of EV Development and Market Challenges
In retrospect of the EV development journey, the first chargeable electric vehicle was born since the automotive electronics have been mature in 1859. The first hybrid electric vehicle hit the market in 1990, followed by a BEV (Battery Electric Vehicle), where the power is supplied by batteries and output by motor. These vehicles offer convenience while reducing carbon emissions at the same time. The emergence of electric vehicles has gradually transformed the future of the automotive market. Furthermore, hydrogen vehicles, garnering increasing attention, has become pivotal in future car development, but there are still some technical challenges to be solved.
Wangchu Chen highlighted, SDV (Software Defined Vehicle) that everyone talks about is also closely connected to the development of vehicles nowadays. For traditional vehicles, each ECU (Electronic Control Unit) is dedicated to different functions which govern the operation of parts and components. As the amount of electronics mounted on a vehicle goes up year by year, the number of ECUs required is also growing. A high-end car model even needs 150 ECUs. Therefore, to address the limit of the electronical/electric architecture (EEA), a centralized control system based on DCU (Domain Control Units) was invented. Then the technical evolution gave rise to the regional architecture ZCU (Zonal Control Unit). The upgraded architecture has been further integrated into a computer hub that gives command. Here, we can refer to it as HPC (High-Performance Computing). SDVs (Software-Defined Vehicles) can constantly refresh their hardware with new features through software updates by OTA(Over-The-Air) technology. All the ECUs are driven by HPC to enable the new features. As smart vehicles have been pushed forward, some problems may arise. For example, communication between ECU and HPC will need higher bandwidth when camera image data is incorporated. This issue presents a significant hurdle for the automotive electronics industry.
Integration and Updates of Automotive Standards
The standards for EV powertrain application have been on a pathway to market and technical innovations. For example, GB/T 29307 (standard set by the People's Republic of China), GB/T 18488 for environment testing, and T/CSAE 143 recently launched demonstrate that EV powertrain system originally assembles individual and single component (traction inverter, gearbox, reducer, and e-motor), and evolve continuously to perform components integration to an all-in-one system.
The international standards for traditional automobiles have also seen consolidation and revisions. Below is a summary of the major updates:
- Performances:IEC 60785 (1984) and IEC 60786 (1984) were combined into ISO 21782 (2020).
- Environment:ISO 16750 (2003) was revised in 2010. During the period, ISO 19453 (2018) was regulated specifically for electric vehicles. In 2023, a new edition of ISO 16750 was released, and integrated contents from ISO 19453.
- E-load:ISO 21780 (2020) was developed on the basis of LV 148 (2013), and ISO 21498 (2021) was developed on the basis of LV 123.
- IP code:ISO 20653 (2006) was revised in 2013 and 2023.
Considering that the testing items for traditional fuel cars are not completely applicable to electric vehicles, ISO 16750 was updated with regards to automotive electronics to reflect condition improvements and new definitions:
- ISO 16750-1General:Addition of operating modes for 48V, Hi-voltage class B, definition of different loads, and auxiliary device (liquid cooling system).
- ISO 16750-2 Electrical Loads:Extension of voltage frequency range from 25kHz to 200 kHz to fit electric vehicles with a DC/DC converter; introduction of test requirements for supply voltage under short duration (reaches10µs) at Micro Interruption test.
- ISO 16750-3 Mechanical Loads:Due to the absence of some parts and components of traditional vehicles, testing methods cannot fully apply to those of electric vehicles. Consequently, more specific items and definitions have been introduced so that when suppliers are putting passenger and commercial vehicles to test, they can select applicable testing conditions. Additionally, the number of mechanical shock test is increased, and the drop test will vary in testing conditions and specifications depending on different weights.
- ISO 16750-4 Climatic Loads:Going with thinking model of OEMs, the process starts with temperature measurement on DUT before testing. Parts and components should reach thermal balance and dwell time is calculated in order to make sure DUTs under set-up conditions. Meanwhile, introduction of humidity cycling test, and partial discharges at altitude test.
It is important to note that one distinct characteristic of automotive standards is sequential testing requirements. For instance, LEG 1 requires three samples to be tested all items from start to end. This is a significant difference between automotive and commercial standards.
Conclusion
The development trend of future cars will lean toward high power density, including all-in-one, high voltage, and high power. Fueled by AI and intelligent vehicles, SDV is recognized as a contributing force in the industry. In response to these trends, the international standard ISO 16750 has undergone revisions in four crucial areas: general - updated definition of operating modes; electrical loads - addition and adjustment of voltage and performances; mechanical loads - testing conditions specific to fuel, hybrid, or electric vehicles; climate loads - updated testing conditions for thermal stability, and so on.
Suppliers of automotive part and component can proactively screen potential quality risks through the reliability tests specified in the ISO 16750 standard. Thus, they are more likely to minimize unforeseen issues of products used in a vehicle and satisfy fundamental requirements. Additionally, during automotive validation, customers are often confronted with a myriad of intricate challenges. Wangchu Chen exemplified the following testing experiences and insights for industry peers to consider:
- Adopt a cooling solution for automotive components or perform the temperature shock testing with high temperature and low temperature water applied in turns.
- Switch the voltage and frequency of charging stations during validation tests, and record all parameters and complicated wave forms
- Take care of the needs for full scope of voltage.
- Low voltage with high current may appear in the parts and components testing of Level 3~5 autonomous driving vehicles.
- Special validation requirement for humidity in VW 80000.
- Examine its operating modes on ice-covered surfaces, soak samples in ice water, and assess its heat dissipation capacity on mud-coated surfaces, and so on.
DEKRA iST is committed to delivering solutions, drawing on our wealth of testing experiences and service capacity to provide professional consultation in automotive standards. We collaborate closely with customers to navigate a diverse array of validation challenges.
Wangchu Chen is invited by EETimes & EDN Taiwan/Asia/India to have an interview of future vehicle insights.
To make all your PROBLEMS SOLVED, we provide professional advisory and validation service.
For more information or service, please feel free to email to 📧 sos@dekra-ist.com