Reduction of the Electromagnetic Torque Oscillation during the Direct on Line (DOL) Starting of a 6 kV Motor by Means of a Controlled Vacuum Circuit-Breaker

Abstract

This article deals with the issue of the reduction of the oscillation of electromagnetic torque in the case of a direct on line (DOL) starting of a 6 kV induction motor. Such engines are used in drive systems where frequent starting may be required. Direct starting in such systems may reduce the mechanical and thermal durability. Therefore, the article presents a method of DOL starting of a 6 kV induction motor with the use of vacuum circuit-breakers and appropriate switching of the voltages supplying the electric machine. To confirm the advantages of the proposed solution, computer simulation and experimental tests were carried out, which are presented and discussed in the article. The obtained results confirm the advantages of the proposed solution, compared to the classic starting known from the literature.

Keywords

• oscillations of the electromagnetic torque
• direct on line (DOL) starting of induction motors
• vacuum circuit breaker