Asynchronous motor-driven machine having variable torque demand, such as household refrigerator compressors

摘要

In an assembly of a work-performing machine having variable torque demand driven by an asynchronous motor, a phase-angle control device for varying the operating voltage of the asynchronous motor in accordance with the respectively required torque, the asynchronous motor being operable with substantially optimal efficiency, by means of said phase angle control device, with the operating voltage matched to the respectively required torque.