Magnetically coupled components target frequencies of up to 500kHz

When compared to components that are not magnetically coupled, SMP’s offerings are less expensive, more compact and produce lower loss balances. The quality factor is set without exposing the choke to any thermal load, and EMC considerations are reduced. The magnetising and leakage inductances can be specifically set by adjusting the magnetic coupling. This is done by varying the geometries of the injection molded parts and using different coil types, such as separately wound coils, bifilar coils or superimposed wound coils.

The range of magnetically coupled components is designed for currents of up to 2000A and frequencies of up to 500kHz, which can be increased to 2MHz in special applications. SMP uses powder composite materials that have been developed and manufactured entirely in-house and feature lower eddy current and magnetic reversal losses. The three-dimensional isotropy of the materials results in compact, lightweight structures, because the magnetic circuits are minimised. This also lowers the magnetic field strength and reduces the quantity of winding material needed. Special magnetorestriction-free materials ensure that components run very quietly. These materials, which are developed and produced according to individual customer specifications, have a high saturation induction, up to 2 Tesla. The oscillation behaviour of the choke can be adjusted specifically by using certain materials or appropriate, magnetically coupled constructions with multiple coils.

Depending on the application, the magnetically coupled components from SMP are constructed for use as transducers, medium-frequency transformers, flux-compensating chokes or controlling chokes. Controlling chokes are produced by adding another coil in the role of transformer. They are implemented, for example, for control signals, to monitor choke saturation, measure current, adjust the quality factor and set a specific induction by premagnetising the magnetic material.

The components can be manufactured with dimensions ranging from 19 to 300mm, weighing 0.05 to 130kg, and up to temperature class H. Protection classes up to IP66 are available according to the intended application. All components are RoHS and REACH-compliant, and the materials used are UL listed. SMP has its own, UL-approved insulation system and in-house capability to issue UL certification up to 1000A. For currents higher than 1000A, certification is carried out externally.