Voltage sag have a significant impact on sensitive equipment and cause economic losses to users. Due to different power system conditions and load conditions, VTC (Voltage Tolerance Curve) of sensitive equipment has an area of uncertainty, so the fault condition of sensitive equipment is difficult to determine. In this paper, an equipment sensitivity evaluation method based on kernel density estimation is proposed. This method evaluates the probability density function of VTC based on the sample data of VTC without making any subjective assumptions about the distribution. Adjustable speed drive is taken as an example, and the proposed method is compared with the traditional method in case studies. The results show that the proposed method has smaller evaluation error and better adaptability compared with the traditional methods.
