Knowledge of the Phase is crucial for the Analysis of all dynamic hydraulic Systems

Modern powertrains place high demands on the integrated control systems to ensure stable and efficient operation of the dependent processes: Be it combustion processes of classical drive concepts even with climate-neutral fuels or a reduction of the power demand of the coolant pumps of an electric vehicle to reduce energy losses in the vehicle periphery. Many vehicle-specific control loops are controlled, regulated and optimized with the aid of pressure sensor signals. Here, optimization is often exclusively based on low static measurement deviations, robustness and the price of the sensors used. The current standard in sensor data sheets lacks information on measurement or signal quality in the acquisition of dynamic signals. A comprehensive investigation of the dynamic behavior of pressure sensors and an evaluation of the acquisition quality of highly dynamic system states provides a decisive contribution to the development and specific optimizations. This paper presents results of a highly dynamic calibration system and focuses not only on the amplitude fidelity of the sensor signal, but also explicitly considers the phase offset of individual sensor types. The dynamic behavior of pressure sensors incl. measuring amplifiers with analog and digital filters is evaluated. The phasing always represents a great challenge in the interpretation of the measurement signals and the derivation of the system behavior. This topic is even more important by the persistent increase of digital sensors in vehicles. The occurrence of aliasing effects in the asynchronous data acquisition by the ECUs and the integrated digital signal processing already in the sensor can lead to errors in the downstream sensor signal processing. Their effects and interactions can usually be sufficiently compensated and thus controlled with detailed knowledge of the occurring signal influences. Initial results of a dynamic investigation of digital pressure sensors are also the subject of this publication.