Detection of High-Resistance Connections in Industrial Power Systems During Induction Motor Start-up

We propose a methodology for detecting and isolating high-resistance connections (HRC) in industrial power systems during induction motor (IM) start-up. Negative sequence components are analyzed during the IM start-up transient in different points of the electric system of an industrial plant. The effects of HRC are evaluated using an analytical model of an industrial power system in steady state and validated with numerical simulations obtained of a transient model. These results show not only the possibility to detect HRC but also its isolation from unbalance voltage conditions of the grid. In addition, an approximation of the total power of motors affected by the HRC is calculated with our proposal. This power and the electric one-line diagram of the industrial plant allow us to determine the location of HRC. Finally, the proposal is validated by using experimental results obtained in a meat processing industry.