A Magnetic Field Reconstruction Scheme for Inductive Power Transfer Systems to Cross Metal Appliances

Inductive power transfer (IPT) technology is considered as a feasible solution to achieve meter-level wireless power supply for state-aware devices of smart grids at high-voltage potential points through cascaded insulators. Power transfer is, however, believed to be severely affected by the influence of metal appliances such as aluminum flanges. A magnetic field reconstruction scheme for IPT systems to cross metal appliances is proposed in this article. The impact of metal appliances on the IPT system is analyzed under the above scenarios. The proposed metal crossing scheme (MCS) can significantly suppress the coupling coefficient attenuation and eddy current loss of the IPT system caused by aluminum flanges. The mechanism of MCS is analyzed through electromagnetic field theory, and the parameters are optimized to achieve better results. Models of the electrical circuit and magnetic circuit are constructed, and the MCS-IPT composite system is analyzed. A prototype of the system is built to simulate two-stage post insulators containing an IPT system. The multicomponent power losses of the IPT system under different scenarios are compared and analyzed. Considering the influence of the aluminum flanges and the proposed MCS, the power transfer efficiency of the system can still exceed 80%.