Internal combustion engine and method for operating an electromechanical camshaft adjuster

An internal combustion engine, comprising:

• a crankshaft;
• a camshaft;
• an actuating gearing configured to electromechanically adjust the camshaft;
• an actuating motor configured to operate the actuating gearing via a motor shaft;
• a first device configured to detect an angular position of the crankshaft;
• a second device configured to detect a reference position of the camshaft;
• a third device configured to detect an angular position of the motor shaft;
• a camshaft control unit configured to:
• control the actuating motor,
• determine an angular position of the camshaft solely based on signals received from the second device and the third device, and
• calculate a phase angle of the camshaft with respect to the crankshasft based on (i) signals received from the first device, the second device, and the third device, and (ii) a transmission ratio of the actuating gearing;
• and
• an engine control unit linked to the first device and to the camshaft control unit, the engine control unit configured to control the engine based on the phase angle of the camshaft,
• wherein an accuracy at which the phase angle of the camshaft is calculated is at least 5 times greater than an accuracy at which the angular position of the crankshaft is detected.

An internal combustion engine comprising:

• a crankshaft;
• a camshaft;
• an actuating gearing configured to electromechanically adjust the camshaft;
• an electric motor configured to operate the actuating gearing, the electric motor including a rotor;
• a camshaft control unit;
• a first sensor configured to detect an angular position of the crankshaft;
• a second sensor configured to detect a reference position of the camshaft;
• and
• a third sensor configured to detect an angular position of the rotor;
• and
• an engine control unit configured to:
• receive the detected angular position of the crankshaft from the first sensor,
• receive the detected reference position of the camshaft from the second sensor,
• determine a timing relationship between a reference position of the crankshaft and the reference position of the camshaft, and
• asynchronously transmit the timing relationship to the camshaft control unit;
• wherein the camshaft control unit is configured to:
• receive the detected angular position of the rotor from the third sensor,
• determine a phase value of the camshaft with respect to the crankshaft based on the timing relationship, the detected angular position of the crankshaft, the detected angular position of the rotor, and a transmission ratio of the actuating gearing, and
• control the electric motor based on the phase value of the camshaft, and wherein an accuracy at which the phase value of the camshaft is determined is at least 5 times greater than an accuracy at which the angular position of the crankshaft is detected.