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Metal film capacitors

Metal film capacitors for onboard power grids

Electronicon capacitors for power electronics can be used for a wide variety of applications, even when extremely non-sinusoidal voltages and pulsed currents are present. Both AC and DC capacitors are available. AC capacitors are periodically recharged during operation, whereas DC capacitors are periodically charged and discharged without a recharge.

The application of AC capacitors

AC capacitors serve as damping or snubber capacitors connected in series with a resistor and are designed for the damping of undesirable voltage spikes caused by the so-called carrier storage effect during the switching of power semiconductors. When applied as commutation capacitors, they are switched in parallel to a thyristor and designed to quench its conductive state. Since commutating capacitors are periodically and abruptly recharged, the peak current will substantially exceed the RMS value. Furthermore, AC capacitors are used in low-detuned or close-tuned filter circuits for filtering or absorbing harmonics.

Metal film DC capacitors

The scope of application for DC capacitors is similarly diverse: Smoothing capacitors help reduce the AC component of fluctuating DC voltage. Supporting capacitors, DC filters, or DC link capacitors are used for energy storage in intermediate DC circuits, e.g. in frequency converters for polyphase drives, transistors, and thyristor converters. They must be able to absorb and release very high currents within short periods, the peak value of the current being substantially greater than the RMS value.

Why choose Electronicon’s metal film capacitors?

  • Over 80 years of experience in capacitors
  • High capacitance density with fivefold the current strength of conventional electrolytic capacitors
  • Own (in-house) metallization of the film
  • Very accurate low FIT rates
  • Compact dimensions: box-type and cylindrical shape

Components you can rely on!

  • Low inductance
  • Very low power dissipation losses
  • High life expectancy
  • Hermitical sealed housing – can be operated under extreme conditions
  • Break-action Mechanism (BAM) – an internal safety mechanism

Applying metal film capacitors in your maritime DC power systems?

Metal film capacitors can be universally used for the assembly of low-inductance DC buffer circuits and DC filters; with their high energy density, they can replace banks of series-connected electrolytic capacitors. The capacitance in a DC buffer circuit must be sufficiently sized to handle and smoothen the occurring ripple currents. The field of applications is extensive and includes (e-)transportation, electrical drives, energetics, industry, power supplies, and the maritime industry.

Our experienced consultants are happy to advise you on the right product for your onboard power systems. KWx makes sure you will always meet your special electrical and mechanical specifications!

Contact our specialist Peter for more information about this topic

Astrolkwx team member Peter van den Berg

Peter van den Berg

Peter's extensive knowledge of power electronics, electronics and IT combined with his application knowledge, with specialization in maritime DC power grids makes him the perfect sparring partner to electrical engineers.

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