Electrical device e.g. electric motor, operating method, involves continuously changing pulse width modulated frequency between upper and lower pulse width modulated frequencies in time-dependent manner

摘要

The method involves continuously changing pulse width modulated frequency between upper and lower pulse width modulated frequencies (f ob, f un) in a time-dependent manner, where the value of the upper frequency is changed in a load-dependent manner when an output power of an electrical device e.g. electric motor, is reduced. The value of the lower frequency is changed when the output power of the electrical device is increased. The lower frequency is 500 hertz and the upper frequency is 25 kilo hertz. An independent claim is also included for an electrical device.