Assessing Utility Harmonic Impedance Based on the Covariance Characteristic of Random Vectors

This paper presents a new method to calculate the utility harmonic impedance and the harmonic voltage emission level at the point of common coupling (PCC). Since harmonic current at the PCC commonly exhibits negligible dependence on the utility side background harmonic, the variable item of the background harmonic in the deviation formulation can be eliminated by using the covariance characteristic of random vectors. And then, the utility harmonic impedance, the customer harmonic voltage emission level, and the background harmonic can be calculated in real time. Based on the analysis results of the simulation and the field test case, it shows that the proposed method is effective to reduce the calculation errors caused by the fluctuation of background harmonic, and satisfactory results can be achieved.

[1]  Paulo F. Ribeiro,et al.  Guide for assessing the network harmonic impedance , 1997 .

[2]  Yao Xiao,et al.  Harmonic impedance measurement using voltage and current increments from disturbing loads , 2000, Ninth International Conference on Harmonics and Quality of Power. Proceedings (Cat. No.00EX441).

[3]  Alessandro Ferrero,et al.  Harmonic power flow analysis for the measurement of the electric power quality , 1995 .

[4]  Wilsun Xu,et al.  Measurement of Harmonic Sources in Three-Wire Single-Phase Supply Systems , 2007 .

[5]  W. M. Grady,et al.  Revenue and harmonics: an evaluation of some proposed rate structures , 1995 .

[6]  A. Testa,et al.  A New Method for Statistical Assessment of the System Harmonic Impedance and of the Background Voltage Distortion , 2006, 2006 International Conference on Probabilistic Methods Applied to Power Systems.

[7]  J. D. van Wyk,et al.  On techniques for localization of sources producing distortion in three‐phase networks , 2007 .

[8]  Yilu Liu,et al.  A method for determining customer and utility harmonic contributions at the point of common coupling , 2000 .

[9]  W. Xu,et al.  Measurement of Network Harmonic Impedences: Practical Implementation Issues and Their Solutions , 2001, IEEE Power Engineering Review.

[10]  Gian Carlo Montanari,et al.  Design of shunt capacitor circuits for power factor compensation in electrical systems supplying nonlinear loads: a probabilistic approach , 1997, IAS '97. Conference Record of the 1997 IEEE Industry Applications Conference Thirty-Second IAS Annual Meeting.

[11]  Yang Hong-geng.  A METHOD FOR ASSESSING HARMONIC EMISSION LEVEL BASED ON BINARY LINEAR REGRESSION , 2004 .

[12]  A. Cataliotti,et al.  A Novel Approach Based on Nonactive Power for the Identification of Disturbing Loads in Power Systems , 2007, IEEE Transactions on Power Delivery.

[13]  B. Blazic,et al.  Methods for estimating customer voltage harmonic emission levels , 2008, 2008 13th International Conference on Harmonics and Quality of Power.

[14]  Liu Yingying,et al.  Partial Least-Squares Regression Based Harmonic Emission Level Assessing at the Point of Common Coupling , 2006, 2006 International Conference on Power System Technology.

[15]  Wilsun Xu,et al.  An Investigation on the Validity of Power-Direction Method for Harmonic Source Determination , 2001 .