Coreless Transformer for Power Quality Measurement at Medium Voltage Level

Original scientific paper Measurement of grid voltage harmonic components is an important part of power quality measurements. Current high voltage transformers with iron core are not linear and cannot easily be used for accurate measurement of "polluted" voltages in wide frequency range. In this paper, design details of a new coreless voltage transformer for power quality measurement are given. As a proof of concept, two transformers, shielded and unshielded, were realized. Measurement results of transformer parameters, results of transformer behaviour simulation and results of transformer linearity measurement are presented. These results show that the proposed transformer can be used for power quality measurement at low and medium voltage levels (up to 35 kV) with harmonic voltages up to 50 order.