This paper describes optimal three-phase filter design based on the measured dominant mode of interference. The modes of interference are determined by simultaneously measuring currents and voltages in all phases in time domain, using a multi-channel digitizer. The measured results are evaluated in frequency domain after fast Fourier transform. While usual electromagnetic compatibility measurement equipment is evaluating only one single channel, the described multi-channel technique allows rapid estimation of dominant modes, for stationary loads, but also for cyclo-stationary, transient and nonlinear loads. Using this method, the topology of power line filter for sufficient suppression of a specific mode of interference from commercial of the shelf three-phase power converter is estimated.

A conventional conducted emission test provides insufficient information in terms of differential and common mode interferences. Only the normal mode interference can be measured, which complicates the design or optimization process for a power line filter if needed. Moreover, measurements performed with conventional test receivers are time-consuming and only one measurement channel is available. In this paper, a measurement approach for digital mode decomposition is presented using multiple channels simultaneously. Results obtained with the proposed approach are compared with regular active and passive separation networks.

All-electric aircraft present a new electromagnetic environment in which electromagnetic interference filtering is playing an important role. Together with a maximum take-off weight, the critical need exists for the optimized filtering solutions. A conventional conducted emission test provides insufficient information for the filter design and implementation since it evaluates only normal mode interference and only the total noise that is present in the system can be measured. This paper presents the measurement procedure using multichannel time-domain measurements to evaluate differential and common mode interference that propagate towards both sides of the system in the powertrain of all-electric aircraft. By implementing the described technique, the optimal volume, weight, and placement of filters can be found.

Electromagnetic interference filters are being characterized in terms of their insertion loss. CISPR 17 provides measurement procedures for assessing normal, common, and differential mode insertion loss. Respectively, this requires three different setups to fully characterize the filter. This paper shows an alternative to the CISPR 17 setup resulting in a time-efficient measurement approach that allows the evaluation of all modes of insertion loss of the filter in a single measurement setup. Furthermore, it is extended to an approximate worst-case measurement, as in CISPR 17. Complimentary, the suggested setup is used to perform insertion loss measurements of a filter including line impedance stabilization networks, to assess the more realistic performance of the filter in the conducted emission test.

No abstract