How can you reduce a triplen harmonics neutral current?

Adding harmonic filters at the load is an effective method for reducing triplen harmonics neutral current. Triplen harmonics, which are multiples of the third harmonic (i.e., 3rd, 9th, 15th, etc.), have a unique characteristic of being in phase and can sum up in the neutral conductor, leading to overheating and potential overload conditions. By implementing harmonic filters, you can actively mitigate these harmonics before they enter the neutral system.

Harmonic filters work by either passively or actively filtering out the unwanted harmonic frequency components while allowing the fundamental frequency to pass through. This reduction in triplen harmonics helps to alleviate the associated neutral current issues, ultimately improving the overall power quality and reliability of the electrical system.

The other options do not directly address the issue of triplen harmonics as effectively. For instance, rewiring the circuit may not directly reduce harmonics unless specifically designed to do so, and increasing transformer capacity generally deals with load capacity rather than harmonic generation. Decreasing load demand may reduce the total current but does not specifically target harmonic mitigation. Therefore, the most viable approach for managing triplen harmonics is indeed to add harmonic filters at the load.