Non-contact Current Measurement Method for Multi-conductor in Digital Twin Based on Magnetoresistance Sensors and PSO

Nowadays, power grid is in process of digital transformation. In order to realize the digitalization and digital twin of power grid, an extensive sense network based on all sorts of smart sensors must be established. Among the sense network, current is one of the most important sense quantities, which provide fundamental data for monitoring, metering and protection of power grid. Most of the present current measurement methods require the contact with the conductor, and can only measure one current at the same time. However, there are plenty of multi-conductors in power grid such as bundled line and multicore cable, which require a new measurement method to obtain values of multiple currents simultaneously. Thus, a non-contact current measurement method for multi-conductor is proposed in this paper. Tunnel Magnetoresistance (TMR) is adopted as core sense unit. Electromagnetic field theory and Particle Swarm Optimization (PSO) are applied to achieve the measurement of multiple currents. Simulation models and examples are established and analyzed to verify the accuracy and efficiency of the proposed method.