基于i_p-i_q运算方式与离散积分均值滤波的瞬时三相谐波检测方法

Instantaneous harmonics detecting for three-phase circuits based on i_p-i_q calculating mode and discrete integral average filter algorithm

根据瞬时无功功率理论,在基于三相谐波ip-iq运算检测方式的基础上,利用三相三线制电网的有功电流ip和无功电流iq只含3k(k为整数)次谐波的特征,设计应用离散积分均值的滤波方法提取基波的直流分量,再从该直流分量重构得到基波及要检测的谐波分量。理论分析和Matlab仿真实验表明,该检测算法在谐波检测方面既具有较快的响应优势与数字滤波器的准确性,又可以减少运算过程计算量,具有较高的应用价值。

This paper discusses harmonic detection of three-phase circuits based on i_p-i_q calculating mode instantaneous detecing method. With the i_p(i_q ) containing only 3k harmonics (k is integer), the filter can be designed as a moving average filter. This paper proposes a filtering algorithm to obtain direct component of foundational current by using discrete integral average calculation. The foundational current can be reconstructed by transforms, and harmonic currents can be gained by reducing.This filter algorithm is lesser in calculation. Theoretical analysis and simulation show that the detecting method has an advantage of dynamic performance of digital filtering in harmonic detecting system and it can be used in harmonic detection of three-phase circuits.