自适应锁相环的设计与仿真

在三相电压不平衡时,负序分量会在Park变换后产生一个2倍基频的波动,进而影响对基频分量相位的提取。针对一般的锁相环在电网三相不平衡时无法准确锁定电网的相位,本文提出一种基于陷波器的自适应锁相环,利用自适应陷波器(ANF)能够输出两个相互正交分量的特点,生成两个能抵消dq坐标系的负序分量,这样就实现了基波的正序负序分离。在Matlab/Simulink中建立仿真模型进行验证,结果表明了文中所提的方法在电网不平衡时可以准确地锁定电网的相位。

Design and Simulation of Adaptive Phase-locked Loop

When the fundamental frequency of the three-phase is not balanced,a negative component of the voltage will be extracted.In view of the fact that the general phase-locked loop (PLL) can not accurately lock the phase of the power grid when the three-phase power grid is unbalanced,this paper proposes an adaptive phase-locked loop based on notch filter.The adaptive notch filter (ANF) can output two mutually orthogonal components to generate two negative sequence components which can offset the dq coordinate system.Thus,the separation of positive sequence and negative sequence of fundamental wave is realized.The simulation model is established in Matlab / SIMULINK for verification.The results show that the proposed method can accurately lock the phase of power grid when the power grid is unbalanced.