Method for operating piezo actuator of fuel injector in accumulator type injection system for IC engine, involves evaluating piezo voltage of piezo actuator by acquiring two values of piezo voltage in response to change in fuel pressure

摘要

The piezo voltage (U) between the connections (30,32) of a piezo actuator (28) is acquired under the effect of fuel pressure (p) in the injection system (10). When the fuel pressure changes, two values of the piezo voltage, each corresponding to the fuel pressure value and independent of the outside potential, are acquired. The piezo voltage is evaluated using the acquired piezo voltage values. An existing pressure sensor (22) detects the fuel pressure. An independent claim is also included for a controller for the piezo actuator of a fuel injector.