Cloud Model Based Evaluation of Equipment Sensitivity to Voltage Sag

The sensitivity of sensitive equipment to voltage sags depends on the characteristics of voltage sag on the power supply site and the voltage tolerance of equipment. It is multi-uncertain including stochastic and fuzzy. Cloud model is used to present the sensitivity of equipment in this paper. The direct normal cloud generator was used to translate the qualitative distribution of VTC into quantitative one. After the numerical values of probability density function of VTC was calculated, the failure probability of equipment was determined. The simulation results for PC have proved that the proposed method is correct and reasonable.