Frequency and duration of voltage drop in plants with intermittent loads

The authors present a fast and approximate method for calculation of frequency and duration of voltage drops in plants which have a large number of intermittent loads such as welders and robots. The intermittent nature of welder and robot loads is approximated by the Markov model for computing the frequency and duration. A novel approach combining the Markov model with voltage drop calculations by aggregating states is presented to compute the magnitude, probability, frequency, and duration of voltage drops. In addition, this method is used to analyze flicker problems due to intermittent loads and evaluate the effectiveness of mitigation methods.<>