Current Sensing Architecture in Electric Power Steering Systems

This technical report discusses the critical role of current sensing architecture in Electric Power Steering (EPS) systems, particularly in the context of achieving ASIL-D compliance. It outlines various current sensing methodologies, including traditional low-side shunt sensing, multi-phase low-side sensing, and in-line sensing architectures. The report details the limitations of traditional approaches, such as measurement gaps and complex reconstruction algorithms, which can hinder performance and complicate safety analysis. It also presents the advantages of in-line sensing, which provides continuous measurement and simplifies diagnostics, thereby enhancing system reliability. The report emphasizes the importance of choosing the right architecture to improve control performance and facilitate certification processes. Additionally, it highlights the benefits of integrated magnetic current sensors, which reduce power loss and component count while ensuring robust diagnostics and compliance with automotive standards.