A novel single-phase phase-locked loop based on adaptive filter

The single-phase phase-locked loop (SPLL) plays a very important role in single-phase power systems. This paper presents a new kind of SPLL based on the adaptive filter. First the least mean square algorithm based adaptive filter is used to produce the required orthogonal signals. Moreover, the decoupling function between the front-end orthogonal signals generator (OSG) and the post-stage phase locked loop is realized in the proposed SPLL structure. Compared with traditional OSG and SPLLs, the proposed SPLL can provde better dynamic performance because its bandwidth can increase significantly due to the decoupled structure. Finally, the experimental results demonstrate the feasibility of the presented SPLL.