Resonance Identification and Attenuation for EMC Study in AC-HERIC Topology

In this paper, validation of a studied Electromagnetic interferences (EMI) mitigation methodology is carried out. The method is applied to AC-HERIC topology as another topology of transformerless single-phase PV inverters, which contains a variety of switching cells. For this reason, a proposed high-frequency model is simulated using a SPICE-based circuit type to predict the conducted EMI generated in this topology. The mitigation strategy entails locating the switching cell that is considered to be the most disturbing source of conducted EMI. Subsequently, variations of some intrinsic parameters of the Si-MOSFET of the selected EMI source. Then, a considerable effect on electromagnetic interference in the high-frequency range (150 kHz- 30MHz). The results are shown in the time and frequency domains to demonstrate that mitigating conducted EMI in power inverters with multiple switching cells is possible by choosing a Si-MOSFET reference with the right intrinsic parameters for the most disruptive cell.