中文摘要：

将电压暂降事件与敏感设备的电压耐受特性曲线相结合，综合考虑幅值、持续时间和暂降频次三要素的作用，提出利用过程性能指数评估电压暂降对敏感设备的影响程度。首先根据幅值和持续时间计算单一事件相对于电压耐受特性曲线的严重程度指数，然后结合暂降频次计算电压暂降严重程度指数的均值和标准差，最后根据均值和标准差计算电压暂降过程性能指数、年电压暂降过程性能指数，作为评估电压暂降对敏感设备影响程度的指标。通过仿真，验证了该方法的实用性和正确性。

英文摘要：

This paper combines voltage sag event with the tolerant curve of voltage sag on sensitive equipment. Comprehensively considering amplitude, duration and sag frequency, the process performance index is proposed to estimate the influence degree of voltage sags on sensitive equipment. According to amplitude and duration, the severity index relative to the tolerant curve of voltage sag is obtained. Mean and standard deviation of the severity indices of voltage sag are calculated based on the annual frequency, the process performance index of voltage sag and the annual process performance index of voltage sag are obtained according to mean and standard deviation, which are treated as the index to estimate the influence degree of voltage sags. Through simulation, the effectiveness and practicality of the proposed method are validated.