Abstract
Keywords
stop-start operation, bidirectional crankshaft sensor, start time reduction, fuel economy
Abstract
Siemens VDO has set up a demonstration vehicle to evaluate different stop-start strategies to reach future CO2 targets. This vehicle is equipped with both a SSG-system (Side mounted Starter Generator) and a conventional starter. Both starter technologies are combined with a so-called startoptimization strategy, implemented in the engine control unit (ECU). The start-optimization strategy is based on injection/ignition upon start request without performing a new synchronization. This requires knowledge of the absolute engine stop-position by the ECU. For that purpose, Siemens VDO also developed a new bidirectional crankshaft sensor, for tooth- and direction detection on toothed - or encoded target wheels. Experimental results show the potential benefits of this solution in terms of starting time and fuel economy.