基于部分岭估计的系统谐波阻抗与谐波发射水平的评估方法

Assessing Harmonic Impedance and the Harmonic Emission Level Based on Partial Ridge Estimate

提出了利用部分岭估计原理对电力系统谐波阻抗进行估计的方法,能够有效提高谐波阻抗估计精度。采用由系统侧与用户侧构成的简单等效电路,在公共连接点处测出各次谐波电压及谐波电流。根据回归方程,利用部分岭估计求得回归系数,即谐波阻抗值,其中岭参数结合岭迹法获得,再对用户侧的谐波发射水平予以评估。该法获得的回归系数具有较小的均方误差,并且克服了广义岭估计存在对特征值过度修正的问题。运用Simulink进行仿真分析,结果表明仿真数据与理论分析较为一致。

A new method for assessing harmonic impedance is presented based on partial ridge regression. This method improves estimation accuracy of harmonic impedance. Using equivalent circuit consisted of both system side and customer side, harmonic voltage and current can be measured synchronously at public connection （PCC）. Regression coefficients is deduced through regression equation and ridge parameter is calculated by ridge trail method. The proposed method generates smaller estimation error and overcomes estimation problem resulted from generalized ridge estimation method. Simulation results proved that proposed method is useful to analyze harmonic impedance.