Abstract: Various embodiments includes a method for determining energization data for an actuator of an injection valve of a motor vehicle comprising: receiving input data at a control unit; and determining the energization data based on the received input data into account with the control unit. Determining the energization data includes using a polynomial regression model.

Abstract: A method for identifying faulty components of a fuel injection system is disclosed, wherein a secondary injection is performed individually by each injector during a test routine, after the secondary injection several predefined parameters of the fuel injection system are determined, and a combined assessment of the determined parameters is used to draw conclusions about whether or not components of the fuel injection system are faulty.

Abstract: The invention relates to a method and a device for actuating an injection valve, which has a piezo actuator and a nozzle needle, of a fuel injection system of an internal combustion engine, in which method a control unit, in a manner dependent on a setpoint stroke height of the piezo actuator in successive injection cycles, outputs a control signal for changing the actual stroke height of the piezo actuator, characterized in that the control unit changes the setpoint stroke height of the piezo actuator, for compensation of the temperature dependency of the capacitance of the piezo actuator, in a manner dependent on the temperature of said piezo actuator.

Abstract: Various embodiments includes a method for determining energization data for an actuator of an injection valve of a motor vehicle comprising: receiving input data at a control unit; and determining the energization data based on the received input data into account with the control unit. Determining the energization data includes using a polynomial regression model.

Abstract: The present disclosure relates to internal combustion engines. The teachings thereof may be embodied in methods for determining a state of an injection valve of an internal combustion engine. Some methods may include actuating the piezo actuator in a pulse-width-modulated manner; recording the T on and/or T off switching times of the pulse-width-modulated piezo output stage of the piezo actuator; and evaluating the recorded switching times to derive the state of the injection valve.

Abstract: The present disclosure relates to fuel injectors. The teachings may be embodied in a method for characterizing a hydraulic coupling element. The fuel injector may have a piston to pressurize a hydraulic medium and a pin connecting the piston to a piezoactuator. The method may include applying a charging current to the piezo actuator low enough that the leakage flow prevents a pressure differential and the nozzle needle remains closed; discharging the piezo actuator with a current high enough to release the mechanical connection between the piston and the pin; detecting when the piston impacts on the pin; and characterizing the coupling element based on the time between discharge and impact.

Abstract: The invention relates to a method and a device for actuating an injection valve, which has a piezo actuator and a nozzle needle, of a fuel injection system of an internal combustion engine, in which method a control unit, in a manner dependent on a setpoint stroke height of the piezo actuator in successive injection cycles, outputs a control signal for changing the actual stroke height of the piezo actuator, characterized in that the control unit changes the setpoint stroke height of the piezo actuator, for compensation of the temperature dependency of the capacitance of the piezo actuator, in a manner dependent on the temperature of said piezo actuator.

Abstract: A piezo-driven fuel injector is modeled by measuring the actuation current and the actuation voltage of the piezo injector, transforming the actuation current and the actuation voltage into the frequency domain, forming a complex conductance from the actuation current transformed into the frequency domain and the actuation voltage transformed into the frequency domain, and determining one or more parameters of the piezo injector from the complex conductance. Once the complex conductance is determined it is used to detect a fault in the piezo injector.

Abstract: A method for identifying faulty components of a fuel injection system is disclosed, wherein a secondary injection is performed individually by each injector during a test routine, after the secondary injection several predefined parameters of the fuel injection system are determined, and a combined assessment of the determined parameters is used to draw conclusions about whether or not components of the fuel injection system are faulty.

Abstract: The present disclosure relates to internal combustion engines. The teachings thereof may be embodied in methods for determining a state of an injection valve of an internal combustion engine. Some methods may include actuating the piezo actuator in a pulse-width-modulated manner; recording the T on and/or T off switching times of the pulse-width-modulated piezo output stage of the piezo actuator; and evaluating the recorded switching times to derive the state of the injection valve.

Abstract: The present disclosure relates to fuel injectors. The teachings may be embodied in a method for characterizing a hydraulic coupling element. The fuel injector may have a piston to pressurize a hydraulic medium and a pin connecting the piston to a piezoactuator. The method may include applying a charging current to the piezo actuator low enough that the leakage flow prevents a pressure differential and the nozzle needle remains closed; discharging the piezo actuator with a current high enough to release the mechanical connection between the piston and the pin; detecting when the piston impacts on the pin; and characterizing the coupling element based on the time between discharge and impact.