This Application Note provides a compact and practice‑oriented guide for designing a three‑phase EMC mains filter. Its goal is to offer developers a clear and structured workflow—from analysing disturbance sources, to the mathematical design of filter components, and finally to simulation and validation in the EMC laboratory. The methods presented are based on real measurements performed on a 4 kW industrial fan with an integrated inverter, demonstrating how the required filter attenuation can be derived from these results.
Using a fully calculated example, the document illustrates how the filter is structured, dimensioned, and simulated with LTspice. In addition, the Application Note addresses important practical aspects such as
The described procedures enable the development of a robust and cost‑efficient EMC filter for three‑phase applications while ensuring compliance with the required emission limits.
Download: ANP137
