Assessment of Point on Wave Switching of Power Transformer
Keywords:
Closing angles, Inrush current, Point-on-wave (PoW) controlled switching, Power transformer, PSCAD, Transient voltage dip (TVD), VGAPAbstract
Point-on-wave (PoW) switching of power transformers is a controlled switching technique aimed at reducing inrush currents and associated electromagnetic transients. Traditional circuit breaker operations introduce high inrush currents due to random closing angles, leading to equipment stress, voltage dips, and power quality issues. PoW switching mitigates these problems by synchronizing breaker closing instances with the transformer’s residual flux and the voltage waveform. This study explores the principles of PoW switching, its impact on transformer energization, and its advantages in enhancing system reliability, reducing mechanical stress, and improving overall power system efficiency. Simulation results and practical implementations demonstrate the effectiveness of this technique in minimizing transformer inrush currents, ultimately extending the operational lifespan of power transformers and associated electrical components.
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