基于背景谐波最小波动能量的系统侧谐波阻抗估计

系统侧谐波阻抗的计算是估计谐波发射水平的关键。文中提出了一种基于背景谐波最小波动能量的系统侧谐波阻抗估计方法。利用公共连接点量测数据的波动量构造全息矩阵,形成波动方程,将系统侧谐波阻抗的求解转化为一个最小二范数问题,用Lagrange乘子将等式约束条件并入目标函数中形成最小波动能量目标函数,精确筛选出背景谐波波动最小的波动量样本,从而求取系统侧谐波阻抗。仿真分析与实际工程案例表明该方法在求取系统侧谐波阻抗时可以有效抑制背景谐波的干扰,具有准确性和有效性。

Harmonic Impedance Estimation on System Side Based on Minimum Fluctuation Energy of Background Harmonic

The calculation of the harmonic impedance on the system side is the key to estimate the harmonic emission level. This paper proposes a method for estimating the harmonic impedance on the system side based on the minimum fluctuation energy of background harmonic. The method requires a holographic matrix constructed by the fluctuation of measurement data at the point of common coupling to form the wave equation, which changes the solution of the harmonic impedance on the system side into a least two-norm problem. The equation constraint is incorporated into the objective function by the Lagrange multiplier to form the objective function of minimum fluctuation energy. And the fluctuation sample with the smallest background harmonic fluctuation is accurately screened to obtain the harmonic impedance on the system side. The simulation analysis and field case show that the method can effectively suppress the interference of background harmonics when obtaining the harmonic impedance on the system side, which proves that the proposed method is accurate and effective.