TITLE:
Detection of the Critical Duration of Different Types of Voltage Sags for Synchronous Machine Torque Oscillation
AUTHORS:
Jaber Alipoor, Aref Doroudi, Morteza Ghaseminezhad
KEYWORDS:
Flux Trajectory Analysis; Power Quality; Synchronous Motor; Torque Pulsations; Voltage Sag
JOURNAL NAME:
Energy and Power Engineering,
Vol.4 No.3,
May
14,
2012
ABSTRACT: Voltage sages are classified in seven types that in each type, the voltage amplitude and angle of phase voltages are different. We demonstrated that voltage sag types have different effects on synchronous motor, especially on its torque pulsations. Torque pulsations are different in shape of oscillations and moreover, peak torque when voltage magnitude is restored has different correlation with sag duration, as sag type varies. By flux trajectory analysis, we mathematically extracted the critical durations for different types of voltage sags, in the case that the sag begins at the zero angle of the voltage wave. In order to observe the validity of the results, we simulated a synchronous motor subjected to different types of voltage sags. The simulation results confirmed the claim.