Inrush Current Testing

Inrush current testing is used for a variety of purposes including sizing fuses and carrying out power supply performance verification. Effective, accurate inrush testing can do more, including enabling power quality measurements and generating exemplars for machine-learning systems monitoring the power line. Some off-the-shelf AC power supplies offer capabilities for controlled inrush testing, but control dynamics and power limitations affect the shape, peak, and time constants of the results. Also, AC power sources obscure details of the grid connection to a load. To provide more accurate and relevant results, a phase-controlled switch is demonstrated as an alternative that can be used in situ. Established or existing line impedance is automatically included for realistic measurements. This paper reviews the design and performance of a proposed phase-controlled switch, and also reviews application of the measured data for line impedance estimation.