Dynamic Modeling of a Piezoelectric Actuated Fuel Injector

As engine designers look for ways to improve efficiency and reduce emissions, piezoelectric actuated fuel injectors for common rail diesel engines have shown to have improved response characteristics over solenoid actuated injectors and may allow for enhanced control of combustion through multi-pulse profiles or rate shaping. This paper summarizes the development of a simulation model for a piezoelectric fuel injector and associated driver that can be used for injector design and control system verification. The model injection rate, piezo stack voltage, and piezo stack current are compared to experimental injection rig data for two different rail pressures.