基于固定频率二阶广义积分器的改进型i_(p)-i_(q)谐波检测算法

Improved i_(p)-i_(q) Harmonic Detection Algorithm Based on Frequency-fixed Second Order Generalized Integrator

针对电网存在频率突变、直流分量和多次谐波时传统i_(p)-i_(q)算法谐波检测精度不高的问题,提出一种基于固定频率二阶广义积分器的改进型i_(p)-i_(q)谐波检测算法。该算法首先利用改进型固定频率二阶广义积分器滤除电网中直流成分和多次谐波,并克服传统二阶广义积分器产生的正交信号不等幅问题;然后利用一种基于改进型固定频率二阶广义积分器的锁相环提供更准确的电网频率,从而得到更准确的检测效果。最后,仿真算例验证了所提方法的有效性。

To solve the problem that the accuracy of traditional i_(p)-i_(q) algorithm is not high when there are frequency mutation,DC component and multiple harmonics in the power grid,an improved i_(p)-i_(q) algorithm based on frequency-fixed second order generalized integrator(SOGI)was proposed.Firstly,the improved frequency-fixed second order generalized integrator was used to filter the DC component and multiple harmonics in the power grid,and unequal amplitude problem of the orthogonal signal generated by the traditional second order generalized integrator was overcome.Secondly,a phase locked loop(PLL)based on the improved frequency-fixed second order generalized integrator was used to provide more accurate power grid frequency,so as to obtain more accurate detection effect.Finally,a simulation example verifies the effectiveness of the proposed method.