Development of a novel dual-coil fuel injector for direct-injection spark ignition engines

Abstract

High-speed DISI injector plays a key role in DISI injector. In order to improve the dynamic response of the DISI injector, a novel dual-coil DISI injector based on vehicle battery-voltage-system was designed. A two stage driving strategy was used to drive the dual-coil injector. The transient electromagnetic FEM (Finite Element Method) model was established based on electromagnetic, mechanical and power losses. The key parameters which directly or indirectly impact on the injector performances were analyzed by simulation, including lines of magnetic flux, magnetic flux density and total loss distribution. Simultaneously, the current loss, eddy current loss and solid loss over time investigated as well. In order to validate the accuracy of the simulation results, the plunger position over time and shot-to-shot flow rate were measured by the laser displacement sensor and flow rate meter. The results indicated that, the simulation results were good agreement to the experimental results. The simulation and experimental results also proved that the comprehensive performances of novel dual-coil DISI injector better than the single-coil DISI injector, expressed as lower power losses and faster dynamic response. Therefore, it has great potential to applicate on the vehicle at enhancing the fuel economy and reducing emission.