A method for controlling and regulating the rotational speed of a converter-fed asynchronous machine

摘要

The performance and utilisation of a converter used to control a variable frequency asynchronous motor. Are improved. Dynamic motor contrl is ensured at high frequencies and low currents. The impressed direct current (Id) between rectifier (T1...T6) and inverter (T11...T16) is made dependant upon the required motr current for the particular speed and load point at which it is desired to operate. Measurement of the direct current (IBist) is only used as a limiting signal for the dc circuit. The required motor current (Isoll) may be determined from a characteristic simulator (11) and a knowledge of required and actual speed and actual current (Imist).