A New Method for Characterizing Voltage Sag Tolerance

It is of great concern to relevant users to accurately describe the tolerance of sensitive equipment to voltage sag. Based on this, this paper presents a description of the voltage sag tolerance of the actual sensitive process by using the process immunity time and the corresponding indexes. The production process controlled by the sensitive equipment is regarded as the sensitive process, and the immunity time is obtained by the change of physical parameters which can be monitored as well as quantitatively reflect the process affected by the voltage sag. Then an interval characterizing the voltage sag tolerance of the sensitive process can be obtained by analyzing and calculating the proposed indexes. The rationality and feasibility of the proposed method are verified by modeling and simulating the speed regulation process of the motor controlled by AC-DC in MATLAB/Simulink.