Identification of Power Lines with Currents Varying Strongly with Changes in Nodal Powers in a Power System

Excessive power (current) flows on the branches (power lines and transformers) of the Power System (PS) may entail serious consequences. Therefore, the possibility of finding the branches of PS where such flows may occur is very desirable for: (i) expansion planning (modernization) of PS, (ii) operational activities of the dispatcher. The paper presents an original method that provides the indicated possibility. The method uses the information contained in the measurement data of nodal powers, branch active and reactive power, or branch currents if PMU devices are in PS. The method was developed using the data mining approach. Knowledge of the strength of correlational relationships between magnitudes and arguments of nodal powers in PS and branch-current magnitudes is used to find the branches on which changes in current magnitudes are strongly related to changes in nodal powers. The considerations show that the considered relationships are not linear. Therefore, the method uses the Kendall’s rank correlation coefficient in the intended investigation. The results of applying the method allow determining soft clusters in PS, which is its additional advantage. The case study shows the use and properties of the proposed method, which are discussed further. The paper ends with conclusions.