Open-core internal resonant transformer with inverter supply

Use of air core or open magnetic core resonant transformers is a modern technique for generating some high reactive powers necessary to test the insulation of power capacitors, cables and high power electric machines. In this paper it is shown the design of a non - conventional open core transformer with internal parallel resonance able to operate within the narrow frequency range agreed by test standards (45 – 65 Hz) by using a simple design power inverter. The transformer - inverter assembly is compact and easily transportable on site as compared to the conventional transformers with closed magnetic circuit.