Design and tests of a hybrid-optical direct current transformer

The designs and tests of a hybrid-optical direct current transformer (HOCT) are demonstrated, which consists of a shunt, a coil, an opto-electric transmission system and some electronics. The experiment results show that the DC measurement meets the 0.2 accuracy class standards and the harmonic measurement confirms with GB/T 14549-93 for harmonic of public power. (4 pages)