Power-line energizing system for active power electronic current transformer

The design of an appropriate power supply is a crucial technological problem when manufacturing an electronic transformer. This paper proposes a new structure for designing such a power supply using a special current transformer (CT), which has two iron cores. The inner core has an air gap. A model is presented and a simulation based on Ansoft Maxwell is made. The results of the simulation agree well with the theoretical analysis, and this demonstrates the feasibility of the scheme of the double-iron-core structure. As long as the inner iron core is not saturated, the overall magnetic flux will continue increasing, so the induced voltage can be prevented from being zero for the majority of the time (except when the induced voltage changes polarity). By means of rectifier, filter, stabilization and DC-DC the voltage induced from the bus bar is converted into three stable voltages supplying the sensor head.