基于新型变步长算法的自适应三相电路谐波检测

Adaptive harmonic detection of 3-phase circuits based on a novel variable step-size algorithm

三相电路谐波自适应逐相检测系统存在动态性能与稳态精度的矛盾,瞬时无功功率理论ip-iq运算方式的三相电路谐波检测系统中,三相谐波检测也直接受到直流分量分离的速度与稳态精度的影响。基于Least Mean Square(LMS)算法自适应理论,推导出自适应检测新型最佳迭代变步长算法,克服自适应算法的动态性能与稳态精度的矛盾,并且将该变步长算法分别运用于三相电路谐波逐相自适应检测与基于无功功率理论ip-iq运算的三相电路谐波检测直流量分离,提高三相谐波检测的质量。理论分析与仿真验证表明,新的迭代变步长算法可以改进三相电路谐波检测跟随性能与准确性能。

There is a contradiction between the dynamic performance and the steady-state error in the adaptive independent harmonic detection of 3-phase circuits. The 3-phase harmonic detection based on the ip-iq calculation mode of instantaneous reactive-power theory is also affected directly by the separation speed of DC components and the steady-state error. Thus, this paper proposes an adaptive optimal variable step-size （OVS） of iteration process based on least mean square （LMS） algorithm to deal with the above mentioned contradiction, and applies the novel method to the adaptive independent harmonic detection of 3-phase circuits and the 3-phase harmonic detection based on the ip-iq calculation mode of instantaneous reactive-power theory, which improves the quality of the 3-phase harmonic detection. Theoretical analysis and simulation results show that the proposed method can detect 3-phase circuits rapidly with lesser steady error.