Electronic transformers
Instrument transformers - Special transformers. Evolution

Electronic current transformers are of interest in high voltage (HV) applications, where they combine the measuring qualities of magnetic transformers with the insulating properties of optical fibers. A typical configuration is shown in figure 5. A distinction is made between measuring equipment, at line potential, a fiber optic link, ensuring insulation, and receiving equipment, at earth potential.

The primary current I_p is measured by means of a current transformer, which does not have to perform an insulation function, and whose secondary outputs to a measuring shunt. The collected voltage is then conditioned and converted into a parallel digital signal. This...