Method for artifically performing thermal and mechanical ageing of rotors for electrical machines

摘要

The method involves subjecting the rotor (1) to a primary electromagnetic field with its current tapping (3) short circuited, whereby the applied frequencies stimulate the rotor to resonant mechanical vibrations and the short circuit currents flowing in the rotor coils (6) rapidly heat the rotor. The frequency of the voltage source (5) can be fixed or variable. The rotor is shaped before applying the commutator and at least before balancing. The rotor is slowly rotated during shaping.