A Novel Current Reconstruction Method Based on Elastic Net Regularization

Indirect current measurement method has played a pivotal role in power grid, owing to the development of inverse problem theory. In this article, a general current source reconstruction method based on the current element model was theoretically proposed. The method discretized the unknown current source region and aimed to reconstruct the actual current distribution according to the synthetical characteristics of discretized current elements. An approximated linear calculation model was derived to construct the inverse relationships between the current element and magnetic field distribution. To solve the ill-posed inverse problem, the elastic net regularization methods under non-Bayesian and Bayesian regimes were presented. The theoretical analysis was implemented under different noise levels. Four current distributions concerning the line current and volume current in practical applications were reconstructed by the two elastic net regularization methods. The results indicated that the methods were feasible in solving this ill-posed inverse problem, obtaining the current parameters and magnetic field distribution effectively. This novel regularization method can be utilized in the measurement of irregular current forms in electrical equipment, leading to an effective and robust approach in operation state acquisition and fault diagnosis of electrical equipment in power grid.