See us at Products and services / HOFER POWERTRAIN Pioneering torque vectoring architectures The ability of electric powertrains to deliver individual control of torque at each axle requires new approaches to hardware and software n the ever-evolving landscape of automotive engineering, torque vectoring technologies represent a significant leap forward in enhancing vehicle performance and safety. Ingenious new systems enable the precise individual control of wheel torques along a vehicle’s axle, embodying a leap in electric individual wheel drive systems with new configurations, efficiency and compactness. The precise distribution and control of torque to each wheel has ushered in a new era of unique cornering behavior and driving stability. This advancement not only facilitates increased cornering speeds but also pushes the boundaries of driving safety, especially across diverse road conditions. Furthermore, torque vectoring technology has transitioned functionalities traditionally managed mechanically to now be adeptly handled by software applications, marking a transformative shift in vehicle dynamics management. Torque vectoring finds its application across a specific spectrum of vehicle segments. High-performance vehicles see a remarkable improvement in driving dynamics, off-road vehicles gain unmatched off-road capability and luxury vehicles achieve unparalleled driving comfort. This breadth of application underscores the technology’s versatility and its role in pushing the boundaries of automotive powertrain technologies. The development of the High Compact Torque Vectoring (HCTV) EDU by hofer powertrain products (HPP) is the culmination of years of expertise and innovation in the field of torque vectoring, specifically in electric individual wheel drives. Since HPP’s initial development of a concentric individual wheel drive for the Audi RSe in 2010, the journey has been marked by relentless pursuit of more efficient, space-saving designs. A significant milestone was reached with the development of the transmission for the AMG SLS Electric Drive in 2013, a vehicle that received excellent feedback from rally driver Walter Röhrl, marking a pivotal advance in drive technologies. The introduction of the first torque vectoring series transmission for the AMG SLS Electric Drive opened new possibilities in electric drive systems. The subsequent development of the transmission for the Karma Revero in 2016, the first individual wheel drive transmission for larger series production, showcased the potential for high-quality, complex drive systems within the mass market. In 2019, a strategic pivot by HPP to develop a highly compact EDU solution as an individual wheel drive led to the creation of the I 2 ABOVE: hofer powertrain’s HCTV torque vectoring series of EDUs offer a modular layout allowing them to be optimized for a range of applications HCTV, a testament to the company’s commitment to innovation and excellence in drive technology. The unique architecture of the HCTV EDU exemplifies innovative solutions to design challenges, such as the limited availability of power modules for outputs over 400kW. This challenge was met by using a 2x3-phase Power Electronics (PE) system for the dual e-motor solution instead of a 1x6-phase PE system for single e-motor applications. The architecture allows the width to be reduced and offers unparalleled flexibility in adapting to various installation spaces and customer requirements, raising the performance (power and torque) density in electric drive technology. The torque vectoring software – the linchpin of this technology – is set to redefine vehicle performance even further. By offering precise control over electric motor torque, it enhances acceleration, cornering speed, off-road capabilities and stability and enables advanced energy recuperation strategies. It accommodates configurations for two, three and four electric motors, enabling unmatched torque distribution that promises to elevate both safety and efficiency. This high adaptability across different motor configurations pushes for maximum safety and efficiency in automotive engineering, promising a future where driving dynamics are not just experienced but tailored to perfection, revolutionizing overall vehicle dynamics and driving behavior by means of software within a software-defined vehicle. Typically, torque vectoring functionality is linked partly to the vehicle control unit (VCU) and partly to the inverter. Here the VCU takes over all the functionality of vehicle state detection and generation of torque demands for each motor, while the torque vectoring EDU and its inverters take care of the torque generation, torque monitoring and synchronization of left and right inverter torque values to control the vehicle stability and safety. As we venture further into the realm of automotive innovation, the journey of torque vectoring technology and software mark important milestones on the road to automotive excellence, redefining the essence of vehicle performance and safety for generations to come. hofer powertrain To find out more, scan the QR code or visit: www.hoferpowertrain.com 52 www.automotivepowertraintechnologyinternational.com / March 2024