Why are the Electronic frequency multi-frequency generators so important？

Electronic frequency multi-frequency generators are not ordinary tools for routine maintenance, but mandatory diagnostic equipment used at critical junctures such as equipment manufacturing, new installation and commissioning (handover testing), and post-overhaul, to perform "deep health checks" on core power equipment (PTs, transformers, GIS, cables).

In short: they are specialized "CT scanners," ensuring the "smooth flow" (healthy insulation) and "sensitive nerves" (precise signal transmission) of transformers, instrument transformers, and other equipment, forming a crucial link in building a robust smart grid security defense.

Their importance lies in their irreplaceable technical means to ensure the safe and reliable operation of the power grid.

• Problem: Many serious insulation defects (such as inter-turn short circuits, winding deformation, and internal particles in GIS) cannot be exposed in conventional power frequency withstand voltage tests.
• Solution: Multi-frequency testing, by altering the electric field frequency distribution, can accurately excite and detect these "potential" defects, preventing equipment from being put into use with defects present.

• Principle: According to the formula V = 4.44fNBA, voltage (V) is proportional to frequency (f) and magnetic flux density (B). The only way to increase voltage V without causing core burnout due to magnetic flux density B saturation is to simultaneously increase frequency f.
• Importance: This is the only safe and effective method for rigorous insulation testing of electromagnetic PTs and transformers.

• Problem: Testing capacitive equipment (such as GIS and long cables) at power frequency requires enormous power capacity (KVA), making the equipment bulky and impassable in the field.
• Solution: Required power capacity S x f. Theoretically, increasing the frequency from 50Hz to 150Hz can reduce the power capacity requirement by 2/3, allowing for field testing with relatively lightweight equipment.

Standard basis: The International Electrotechnical Commission (IEC) and national standards (GB) clearly stipulate that the insulation testing of the above-mentioned equipment requires induced withstand voltage testing or frequency conversion withstand voltage testing.

1. IEC 60076-3 (Power Transformers)
2. IEC 61869-1 (Instrument Transformers)
3. GB 50150-2016 (Acceptance Testing Standards for Electrical Equipment in Electrical Installations)