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The driving comfort is an important factor for buying decisions. For the interior noise of battery electric vehicles (BEV) high frequency tonal orders are characteristic. They can for example be caused by the gearbox or the electric drive and strongly influence the perception and rating of the interior noise by the customer. In this contribution methods for measuring, analyzing and predicting the excitation by the dynamic torque of the electric drive are presented. The dynamic torque of the electric drive up to 3.5 kHz is measured on a component test bench with the help of high frequency, high precision torque transducer. The analysis of the results for the order of interest shows a good correlation with the acoustic measurements inside the corresponding vehicle. In addition an experimental and numerical modal analysis of the rotor of the electric drive are performed.

The number of full electric and hybrid electric vehicles is rapidly growing [1][2][3]. The new technologies accompanying this trend are increasingly becoming a focal point of interest for rescue services. There is much uncertainty about the right techniques to free trapped occupants after an accident. The same applies to vehicle fires. Can car fires involving vehicles with a lithium ion traction battery be handled in the same way as conventional vehicle fires? Is water the right extinguishing agent? Is there a risk of explosion? There are many unanswered questions surrounding the topic of electric vehicle safety. The lack of information is a breeding ground for rumours, misinformation and superficial knowledge. Discussions on various internet platforms further this trend. Tests were conducted on three lithium ion traction batteries, which were fuel-fired until burning on their own. The batteries were then extinguished with water, a surfactant and a gelling agent.

SAE paper 2013-01-0213 [1] described firefighting tests with Li-Ion traction batteries. However, additional knowledge and experience has been gained since then. In 2018 and 2019, DEKRA Accident Research and the Department of Anesthesiology of the University Medical Center Göttingen conducted crash tests far beyond standard with four battery electric vehicles. Three of the vehicles’ batteries were used to test a new method of firefighting. A specially designed lance was used to pierce the battery housing, which enabled water to be directly fed into the housings themselves. The method proved to be very effective, but the tests also showed some limitations. The information gleaned from this series of tests and experience gained from other tests was used as a basis for the formation of a multidisciplinary group of experts.

Electric cars are getting popular more and more and the expectations of the customers are very challenging. Concerning comfort, the situation is clear: customers want an electric car to be quiet and without any annoying noise from the powertrain. To develop an electric powertrain with a minimum noise level and minimized whining it is necessary to have an accurate CAE-simulation and precise criteria to assess whining noise. Based on the experience with electric powertrains in research cars the CAE-modelling was improved and a new ‘whining intensity factor’ was acquired for the development of Daimler's electric cars. The results are a very low noise level and a minimized whining noise, nearly not noticeable giving a comfortable sound to the customers of the smart electric drive and the B-Class Electric Drive.

In the next 20 years the share of small electric vehicles (SEVs) will increase especially in urban areas. SEVs show distinctive design differences compared to traditional vehicles. Thus the consequences of impacts of SEVs with vulnerable road users (VRUs) and other vehicles will be different from traditional collisions. No assessment concerning vehicle safety is defined for vehicles within European L7e category currently. Focus of the elaborated methodology is to define appropriate test scenarios for this vehicle category to be used within a virtual tool chain. A virtual tool chain has to be defined for the realization of a guideline of virtual certification. The derivation and development of new test conditions for SEVs are described and are the main focus of this work. As key methodology a prospective methodical analysis under consideration of future aspects like pre-crash safety systems is applied.

The automotive industry has recently started implementing magnetic gears, in different types, as an alternative design for transmission systems. One such design being the Magnetic planetary gear permanent magnet (MPG-PM) machine. The current methodology and the relevant formulae help to design the magnetic planetary gear system, which does not have design considerations for permanent magnet machines and the influence of magnetic fields. The influence of design characteristics of PM machine, Magnetic field and its material plays a vital role in designing the MPG-PM for electric vehicle applications. A method of optimizing the Gear topology design parameters of a magnetic planetary gear permanent magnet machine (MPG-PM machine) is proposed. The Analytical calculations regarding the design parameters are proposed in relation to power, gear ratios, and other design constraints like packaging parameters i.e., outer diameter, the overall length of the machine.