Current and Voltage Measurement Method Based on Magnetic and Electric Field Sensors for Smart Grid Applications

Voltage and current measurement play essential roles in energy counting, relay protection, smart equipment control etc. Nowadays, the current transformer and potential transformer, which have been used for centuries, cannot meet the newly requirements of digitization, miniaturization, convenience and lower cost for sensors in smart grid. In recent years, the technology and materials of magnetic field sensor which based on magnetoresistance effect, and the electric field sensor which based on inverse piezoelectric effect, have developed rapidly and are widely used in industry. Current and voltage measurement method, which utilizes three magnetic field sensors and one electric field sensor, is derived and proposed in this paper. By applying the proposed method, the current and voltage of the conducting wire can be measured without magnetic core, coil and the contact with the conducting wire, and the measured results are not affected by the position of the conducting wire. Simulation models of the measurement method were established in MATLAB software, and several calculations were executed under various conditions. The validity of the proposed method was verified by analyzing the simulation results.