Optimal design of moving average filter and its application in distorted grid synchronization

This paper focuses on the optimal design of Moving Average Filter (MAF). The necessary and sufficient condition for MAF to filter out a group of harmonics with specified orders simultaneously is deduced based on the presented model. Accordingly, the enhanced MAF (EMAF) algorithm is proposed and used for the fast open-loop phase locking of the distorted grid. Compared with the Cascaded Delayed Signal Cancellation (CDSC) algorithm, the superiority of EMAF is highlighted from the aspects of dynamic response time, transient oscillation amplitude, required data storage size, thorough harmonics elimination and random noise suppression ability. The experiments validate the advantage of the proposed EMAF algorithm.