Abstract reprinted with permission of SAE International.Find a library where document is available. By this approach, standard cost effective solenoid injectors equal or even exceed the performance of piezo injectors. Information about the valve needle motion is gathered from the electrical injector signals in the electronic control unit by utilizing the solenoid injector itself as a sensor. A new sensorless closed-loop control system results in substantial improvement of the dosing performance of solenoid injectors. Compared to piezo injectors solenoid injectors show a much larger tolerance band at low fuel quantities. Besides full valve needle lift, both types of injectors are also analyzed in ballistic operating mode for minimum injection quantities. The investigation focuses on dosing performance, temperature influence and the impact of production tolerances. The performance of outwardly opening piezo-electric actuated fuel injectors is compared with conventional inwardly opening solenoid injectors. Cold start is the most critical phase concerning emission levels. They must perform precise fuel metering, enhanced linear flow range and multi-pulse injection cycles in order to meet tight emission limits and low fuel consumption. Piezoelectric Fuel injectors have what are called stacks of Piezo material in them stacked on top of one another. This results in a change such as pressure or movement in that material. Dosing Performance of Piezo Injectors and Sensorless Closed-Loop Controlled Solenoid Injectors for Gasoline Direct InjectionĪdvanced combustion strategies for direct injection gasoline engines require high performance fuel injectors. Mercedes-Benz has introduced the world’s first gasoline engine with piezoelectric direct injection and spray-guided combustionthe Stratified-Charged Gasoline Injection (CGI) engine. Piezoelectric fuel injector fundamentally works by applying an electrical current to a material.
0 Comments
Leave a Reply. |