Inverter EMI modeling and simulation methodologies

A numerical prediction of electromagnetic interference (EMI) allows evaluation of EMI performances at the design stage and before prototyping. It can also help reduce the post-prototype EMC cost by minimizing late re-design and modifications of a drive implementation. This paper describes two simulation approaches with time and frequency domain simulations and verifies them with experimental results. Both time and frequency domain simulation approaches are found effective as long as the noise source and propagation path are properly modeled. The 3 dimensional finite element analysis (FEA) based parasitic parameter extraction tool - Ansoft Spicelink™™ has been used substantially. To gain additional degree of confidence, the results obtained from FEA are verified with closed-form solutions and actual measurements.