Constant slip control system of an asynchronous motor

Abstract

Asynchronous motors are efficiently controlled using the scalar method. Main problems appear when the motor is fully loaded and desired rotation speed is slow. In such cases, the motor slip exceeds the magnitude of the nominal slip, causing the increase in stator current. The constant slip method was designed to control hardly loaded asynchronous motor. In this particular situation, the constant slip method provides a better efficiency than the scalar method. The magnitude of the motor current refers to the slip: the less is the slip, the less is the magnitude. It is impossible to find the optimal slip for minimization of current with the help of a model. Therefore, the nominal slip value was used as optimal.

Article in Lithuanian.

Pastovaus slydimo asinchroninio elektros variklio rotoriaus greičio valdymo metodas

Santrauka. Pasiūlytas pastovaus slydimo asinchroninio elektros variklio rotoriaus greičio valdymo metodas ištirtas modeliuojant, gauti rezultatai palyginti su skaliarinio valdymo metodo tyrimo rezultatais. Tyrimo rezultatai parodė, kad pastovaus slydimo asinchroninio variklio greičio valdymo metodas yra pranašesnis už skaliarinio valdymo metodą, kai valdomo variklio greitis yra nedidelis ir jo apkrova yra artima nominaliajai.

Reikšminiai žodžiai: asinchroninis variklis, rotoriaus slydimas, dažnio keitiklis, inverteris, valdymo sistema.

Keyword : asynchronous motor, slip, frequency converter, inverter, control system