Development of an optical current transformer for adjustable speed pumped storage systems

The design and testing of a passive optical current transfnrmer utilizing the Faraday effect is described. The Optical Current Transformer (OCT) was developed to measure the rotor excitation current of R 400 MW Adjustable Speed Pumped Storage System. Overall dimensions of the bulk optic sensor are 250 x 250 x 40 mm and the OCT hnctinns as an nvercurrent sensor to a maximum current35000 A This OCT has heen practically applied at the Ohkawachi Power Plant of the Kansai Electric Power Co., Inc. since December 1993.