Drehmomentfluktuationen

Drehmomentfluktuationen, often translated as torque fluctuations or torque ripple, refer to the variations in torque output of a rotating machine, particularly electric motors and internal combustion engines. These fluctuations are inherent to the operating principles of many electromechanical systems and can arise from various sources.

In electric motors, common causes include the discrete nature of magnetic flux distribution in the stator and rotor, cogging torque due to the interaction of rotor teeth with stator slots, and uneven current distribution in the windings. These factors lead to a pulsating torque rather than a perfectly smooth one. The magnitude and frequency of these fluctuations depend on motor design, number of poles and slots, control strategy, and load conditions.

For internal combustion engines, torque fluctuations are primarily caused by the intermittent power delivery from the combustion process of individual cylinders. The firing of each cylinder produces a pulse of torque, and the alternating firing sequence of multiple cylinders results in a net oscillating torque on the crankshaft. Factors like engine displacement, number of cylinders, firing order, and intake/exhaust manifold design influence the amplitude and pattern of these torque variations.

Drehmomentfluktuationen can have several detrimental effects. They can lead to increased noise and vibration, reduced efficiency, premature wear of mechanical components such as gears and bearings, and inaccuracies in positioning systems that rely on precise rotational control. Mitigation strategies often involve careful design considerations, advanced control algorithms, and the use of damping mechanisms or flywheels to smooth out the torque delivery.