Choke inductors are coils for blocking electrical currents. They can buffer energy, modify impedance and filter.

Chokes are used in electrical and electronic device power supplies as well as in high and low frequency technology and power electronics. In contrast to transformers or resonant circuit inductors, chokes are often connected in series to other components or electrical loads.

We are keen to design and manufacture complex chokes. As core materials we use ferrite, powder and amorphous solids. When required, we can incorporate production preferences such as vacuum casting or impregnation as well as special casings.

The following are examples of a multitude of other available choke products.

Mains chokes

Mains chokes minimise system interference produced by rectifiers. Mains interference from inverter drives is also suppressed in compliance to EN 61558. Top quality is guaranteed through precision processing and the use of high quality materials, e.g. insulation material compliant with the B and F UL-insulation systems.

Output chokes

Output chokes are connected in front of inverters to minimise their negative effects. Voltage spikes from in-line motors are reduced to increase motor service life by diminishing insulation loads.

Features: compact construction, 3-phase versions up to 1,500 A, simple installation.

50 Hz line chokes

Line chokes are usually series connected to an electrical load. Single and three phase versions are available. They are intended to provide the following important protective functions:

  • Suppression of harmonic currents resulting from frequency-dependent inductive resistance
  • Soft start for electrical loads for reduced component stress, e.g. in rectifier circuits
  • Guaranteed short circuit voltage of 4% of the mains voltage (uk = 4%) as generally required from power supplier companies 

Common mode chokes

A large range of toroidal commaon mode chokes is available, all type of material are used and especially nancrystalline material which allow a standard range from 0.3 A up to 50 A and far more on custom designed products. All mountings are available, vertical, horizontal, bare coil, and a new range of SMD power chokes.

PFC chokes

PFC (power factor correction) chokes are used to significantly reduce mains harmonic distortions – generally in line with the mains supply in SMPS components. They function either passively for mains frequency on a laminated transformer core or as a storage choke with a powder core in an active PFC switch mode of 10 to 100 kHz.

Storage Chokes

We have solutions for your DC current filtering with our storage chokes. Our standard range goes from 0.3 A to 6.3 A and our customized solutions to several hundreds of Amperes. Vertical, horizontal, bare, in case mountings are available.

Power chokes with upright coils

Power chokes are required for a range of applications e.g. as smoothing chokes for oscillating power supplies, as filter chokes for IGBT rectifiers (sinusoidal filtering), as commutating chokes for mains inverters, as smoothing chokes for intermediate circuits as well as for many other circuit designs. We can also supply upright coiled flat-wire power chokes according to specific customer needs.

Pot core chokes

Our pot core designs are based on a range of different magnetic powder composites. We cooperate with leading core manufacturers who guarantee us reliable quality and supplies. We are able to manufacture pot cores in different standard core sizes or according to specific needs.

Technical features:

  • Less material required
  • Higher switching frequencies through low-loss materials
  • Q factor setting with no thermal load on the choke
  • Higher clock frequencies possible
  • Specific inductance settings
  • Lower EMC costs
  • Very compact and lightweight construction
  • A range of powder materials, iron powder mixes, SiFe powders and sendust

schwa-medico Transformatoren

  • Philipp-Reis-Straße 5
  • 35321 Laubach, Germany