EMI Investigation of Power Electronics Interfaces in Modern Electricity Grids

With the increasing penetration of power converters-interfaced resources in the modern networks, the electricity grids may suffer from the electromagnetic interference (EMI) issues, which result in the voltage surges and transients, threatening the reliable operation of the adjacent sensitive devices. In this paper, the EMI performances of the back-to-back converters, taken into account the impacts of switching frequency, operation modes (uni-direction and bi-direction), and passive filter (common mode filter and decoupling filter), are investigated and analyzed. The common mode equivalent circuit of the power converter is presented in this paper to explain the propagation path of the EMI between the inverter and rectifier. The field measured results are presented to clearly show the EMI performances of the commercial power converters.