Delphi Technologies Next Generation GDi-System – Improved Emissions and Efficiency with Higher Pressure

Authors

Dr. techn. W. F. Piock, Dr.-Ing. G. Hoffmann, J. G. Spakowski MSc, Dr. G. Dober, Dipl.-Ing. B. Gomot, Dr. rer. nat. H. Hülser, Delphi Technologies, Bascharage

Year

2019

Print Info

Fortschritt-Berichte VDI, Reihe 12, Nr. 811

Summary

In 2016 Delphi Technologies successfully started production of the world’s first 350 bar GDi-System enabling its customers to address their demand for higher performance, lower fuel consumption and lower engine emissions, especially particulate emissions.
However, further benefits are achievable beyond 350 bar. Advanced combustion work has demonstrated the potential of increased fuel pressure to further reduce emissions and improve fuel consumption due to better atomization and higher combustion efficiency. These positive results triggered an evolutionary component development of a next generation GDi-System which is capable of fuel pressures up to 600 bar. The developed injector required structural modifications of the high pressure vessel, but optimization of the magnetic path has allowed retaining the same drive energy levels as today’s 350 bar injectors and has allowed maintaining the current packaging envelope. The high pressure pump carries over the 350 bar concept of an outlet metered single piston pump, but requires adaption of some of the critical components and interfaces for the significantly higher loads. The demand for higher pressures at low engine speeds has also led to the introduction of a new internal pump feature which boosts pump efficiency and consequently brake engine efficiency. Complementary to the advances on the wet components, the control system has been developed with a focus on improved injection accuracy over lifetime.
Engine results compare the key performance characteristics, fuel consumption and emissions, against a state of the art 350 bar injection system. This new technology offers an opportunity to make gasoline engines more efficient and significantly cleaner.