xEV Propulsion System Control-Overview and Current Trends 2021-01-0781
Propulsion system control algorithms covering the functional needs of xEV propulsion (‘x’ donates P0-P4 configurations) systems are presented in this paper. The scope and foundation are based on generic well-established HEV controller architectures. However, unlike conventional HEV (series, parallel and power split) powertrains, the next generation of integrated electric propulsion configurations will utilize a single micro controller that supports multiple control functions ranging from the electric machines, inverters, actuators, clutch solenoids, coolant pumps, etc. This presents a unique challenge to architect control algorithms within the AUTOSAR framework while satisfying the complex timing requirements of motor/generator-inverter (MGi) control and increased interface definitions between software components to realize functional integration between the higher level propulsion system and its sub-systems. This paper lists three areas that system control algorithms typically cover: 1) mode determination and reference command conditioning, 2) serviceability, and 3) safety. Furthermore, this paper focuses on Propulsion Integration Metrics which comprises of control features that impact efficiency, NVH, drivability and performance. Definition of these metrics and specific details of algorithms in these areas are well documented in the literature, and this paper aims to provide current trends and an overview to highlight algorithm interdependence, control architecture, and calibration considerations that impact system level objectives in the context of electrified propulsion. In conclusion, the paper looks ahead to adoption of wide band gap devices (e.g., SiC MOSFETs) in automotive high voltage traction inverters and its potential propulsion system level impact.