Design Of Wireless Current Transmitter On The Low-voltage Side Of Distribution Transformers

For a long time, stealing electricity is too difficult to be forbidden, it has beengetting more various, more intelligent and industrial, which, not only brings hugeeconomic loss to power companies, but also disrupts the normal supply ofelectricity. Currently, the common problem, that power companies meet inanti-stealing, consists of hard evidence and outdated technology of anti-Stealing. Itis an important issue to improve the technical level of anti-stealing that theresearchers and inspectors have to face. Therefore, it is of practical significancesignificant to develop an intelligent inspection device for power companies.The wireless current transformer showed in this paper is an important part oflow-voltage intelligent anti-Stealing device. It collects the current signal from thelow-voltage three-phase line of the transformer, and transmits to the inspect host bywireless. Compared with the current parameters of the user’s meter, It can preventelectricity stealing between the transformer and the meter, which fills the currentgap of the research of anti-current-stealing device.This paper has analyzed the principle and workflow of each component,provided the overall design of the wireless Current transmitter, chosen pluggableprecision Rogowski coil as a measuring probe, calculated the RMS of the currentcombined with a three-phase meter metering IC ADE7878. It eliminates the impactof time drift and temperature drift with digital integrator and offset calibration. Thedesign of low-power dissipation control module reduces power consumption of thesystem.In addition, this paper introduces the power supply design of the wirelesscurrent transmitter. Proved by the analysis of magnetic field and magnetic, it is aneffective solution of magnetic saturation. The design of subsequent processingcircuit, consists of transient overvoltage protection, monitoring circuit,rectifier-filter circuit, DC-DC circuit, power management circuitry and rechargeablebatteries.it guaranteed the long-term stable supply of energy, ensured that the powersupply can be adapted to a wide current range.The wireless current transmitter system meets the design index, proved bydebug. Otherwise, it is verified, that, the subsequent processing circuit can supply stably through the simulation of the output voltage of the coil verified.