virtaustahdistushäviöt

Virtaustahdistushäviöt, also known as synchronization losses, refer to energy losses that occur in rotating electrical machines when the rotor's speed deviates from the synchronous speed of the rotating magnetic field. This deviation can arise from various factors, including changes in load, voltage fluctuations, or external disturbances. In AC machines, the rotor is typically driven by the magnetic field produced by the stator windings. Ideally, the rotor would perfectly follow the rotating field, maintaining synchronization. However, in reality, this perfect synchronization is not always achieved.

When the rotor's speed is less than the synchronous speed, the machine operates as a motor, and the difference in speed creates a torque that tries to pull the rotor back into synchronization. This difference in speed, known as slip, results in induction of voltages and currents in the rotor conductors. The interaction of these induced currents with the magnetic field generates torque, but also leads to resistive losses within the rotor. These are the primary virtaustahdistushäviöt.

Conversely, if the rotor speed exceeds the synchronous speed, the machine operates as a generator, and the slip has a negative value. While this scenario also involves energy conversion, the term virtaustahdistushäviöt is most commonly associated with motor operation and the losses incurred due to slip. Minimizing these losses is crucial for improving the efficiency of electric motors and can be achieved through proper machine design, load management, and control strategies that aim to maintain a stable operating speed close to synchronism.