An impedance matrix constrained-based method for harmonic emission level estimation

The harmonic impedances are important for both utility companies and their customers. The data have many uses, such as estimating harmonic emission levels, designing filters. Complex independent component analysis is a well-accepted method for harmonic impedance estimation. However, a lack of data points for each calculation leads to wrong results. To increase the feasibility of this method, we proposed a constrained complex independent component analysis-based method by adding the essential feature of the harmonic impedance matrix. Thus, the recovered source signals, which are highly consistent with the original source signals can be found when the data quantity for each calculation is little. The method has been verified using simulation studies and extensive field data. The results show that the proposed method can serve as a useful tool to support the harmonic impedance calculation task of utility companies and their customers.