Abstract: Precisely controlled piezo diesel fuel injector can improve diesel engine performance. By taking energy dissipation, heat sinking and hardware cost into consideration, a driving module using switching voltage amplifier was designed. A static open loop pulse width modulation (PWM) control method was proposed to control the charging/discharging procedure by turning ON/OFF the MOSFET. As the solution of the difficult calibration of control parameters, an online self-tuning method was implemented. The application test was taken on the fuel bench. Control parameters were estimated through simulation and subsequently tuned online. The results show that the module assures fast response of the injector and stable injection quality, so meets the working requirement of the diesel engine.

Key words: diesel engine, fuel injector, piezo actuator, driving module, self-tuning of control parameters