Simulation Study on Voltage Sag Detection in Phase-Locked Loop of Complex Coefficient Filter
In three-phase power systems,the single-phase voltage drop problem has become the biggest hidden danger affecting the normal operation of power equipment.In this paper,for the traditional single-phase voltage dips detection method with large computation volume,poor dynamic performance and low detection accuracy,we propose an improved voltage dips detection algorithm based on complex coefficients filter phase-locked loop,which realizes the cross-decoupling through the introduction of phase-shift operator,greatly reduces the computation volume of the detection,improves the dynamic performance of the algorithm and the detection accuracy,and is particularly suitable for the rapid real-time compensation of voltage dips,which has a large practical engineering application value.Matlab/Simulink simulation results show that the proposed method can quickly and accurately detect the depth of transient drop,and the accuracy and real-time performance meet the demand of real-time voltage drop detection.