Optimizing Start-Up Procedures to Decrease Magnetizing Inrush Current in Power Transformers

The energization of a power transformer (PT), accompanied by a magnetizing inrush current (MIC), is an important aspect that affects the stability of the electrical grid. This process can lead to significant voltage drops, which, in turn, depend on the ratio of generation capacities to those of the PT being energized. Two effective methods are examined in this article for mitigating MIC in PTs: the implementation of a preinsertion resistor (PIR) and the Point-on-Wave (POW) method. Technical specifications from Brush Company's generators and ABB Company's transformers are utilized in this study, employing EMTP-RV software for analysis. The findings of this research aid in designing electrical power systems (EPSs) by offering insights into limiting MIC in PTs, which is vital for system stability and equipment protection during the startup.