An Improved Method for Voltage Sag Detection Based on Weighted Least-Squares Estimation with Harmonic Models

作者：Lei, He^*; Lin, Xinchun; Kang, Yong; Duan, Yuping; Qiu, Jun

来源：Przeglad Elektrotechniczny, 2012, 88(10A): 238-241.

• dynamic voltage restorer
• voltage sag detection
• harmonic models
• weighted least-squares estimation

A rapid voltage sag detection method based on weighted least-squares estimation (WLSE) with harmonic models is proposed to satisfy the requirement of the dynamic voltage restorer. The covariance resetting technique is adopted to detect the voltage sag accurately and rapidly, even in condition the voltage contains considerable amount of harmonic components. The threshold of covariance resetting is larger than the steady state error between the sample and estimation of the voltage for the purpose of favorable covariance resetting only if the voltage sag occurs. The threshold of covariance resetting can be small because the steady state error will contain little harmonic components by the proposed WLSE method which have a positive impact on the detecting speed even if the depth of voltage sag is low. The algorithm has been tested under different conditions so as to verify its performance on voltage sag detection.

• 出版日期2012
• 单位华中科技大学