基于瞬时无功功率理论的谐波检测中低通滤波器的研究

Low-pass filters in harmonic detection based on the instantaneous reactive power theory

电力有源滤波器基于瞬时无功功率理论的ip、iq运算的谐波检测方法中,对低通滤波器截止频率的选取范围给出理论推导。同时,用MATLAB建立谐波检测仿真模型,针对低通滤波器截止频率及阶数对谐波检测精度和速度的影响进行仿真。通过对仿真结果的分析,得出较为理想的低通滤波器截止频率及阶数,并进行了验证。仿真结果证明,低通滤波器选择截止频率为25 Hz,阶次为3次可以有效检测谐波。

A theoretical range of cut-off frequency of low-pass filters in an ip, iq harmonic current calculation model based on instantaneous reactive power theory in active power filters （APF） is given. A harmonic detection model was established in MATLAB. Simulations were carried out focusing on the impact of low-pass filters on the accuracy and speed of harmonic detection. The choice of a cut-off frequency of 25 Hz and third-order lowpass filters was validated.