Material is the Key in New All-Mode EMC filters from SMP

The material is the key in new all-mode EMC filters with high frequency stability produced by Sintermetalle Prometheus GmbH & Co KG (SMP), a manufacturer of custom inductive components, filter systems, cores and molded parts based upon soft magnetic materials. 

The new specifically developed materials are now effective for frequencies up to the gigahertz range. The all-mode construction simultaneously damps both differential mode and common mode interference, eliminating the need for additional common mode filters, the company says. 

EMC filters reduce interference currents and voltage spikes in power converter systems which are generated by parasitic effects and cyclic elements of the system. The material plays a critical part in this, as Johannes Gemenetzis, managing director of SMP, says.

Johannes Gemenetzis

“The objective is to achieve stable inductance at the working point over the entire frequency spectrum in order to maximize interference suppression. Compared to the standard technologies which use materials such as ferrite, electrical steel sheets and nanocrystalline ribbon, interference levels with the new All-Mode EMC filters are as much as 40dB lower,” said, Gemenetzis.

The new filters are compact and up to 40 percent lighter. They are noiseless because they are made from magnetostriction-free materials. “Due to the stability of their inductivity, these solutions are designed with lower inductance, thus enabling a more dynamic system. The voltage spikes which occur periodically with the switching frequency of the inverter are drastically reduced, so the lifetime of the electric motor is much longer. The overall efficiency of the system is improved due to very low material losses. Moreover, fewer filter components are needed, so volume is reduced and the cost effectiveness of the power electronic system as a whole is increased substantially.” Today’s fast switching SiC and GaN semiconductors place substantial demands on the magnetic materials, a situation which these products are fully equipped to handle, said Gemenetzis.

New EMC filters from SMP

SMP specialises in the customer-specific development and manufacture of filter systems and inductive components. The component portfolio is designed for currents of up to 2000 A, up to 3000 A for special applications, and for frequencies up to the gigahertz range. The materials have been developed and manufactured by SMP specifically for this purpose and have high saturation induction of up to 2 Tesla. The individual components can be produced with dimensions from 19 mm to 300 mm and weights from 0.05 kg to 130 kg.

Their filter systems and inductive components are used in all aspects of power electronics including industrial applications, automation, railway drives, electromobility, marine engineering, medical technology, energy supply and aerospace. 

Based in Germany, SMP operates from two production locations including the headquarters in Graben-Neudorf and another in Austria. Virtually all of its production is customized, with an export rate of more than 50% worldwide.

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