Dc capacitors - Import export

It works - even in your smaller DC links! A few years ago, our PK16TM pioneered the large-scale shift from batteries of electrolytic DC link capacitors to energy-efficient and highly reliable film capacitors which has become so common nowadays. The E61 range makes the benefits of this substitution available for DC links with smaller powers now. With their pin terminals, these capacitors can be integrated directly into your printed circuit board. The capacitors of the E61 series are optimized for high rms and surge currents. Along with their high specific ratio of capacitance to volume, they offer long-term stability and storability, as well as excellent self-healing without loss of capacitance. It is our advanced know-how in special capacitor film coating, combined with many decades of practical experience in designing and manufacturing capacitors, which have allowed us to develop this range with its numerous advantages over traditional electrolytic capacitors:

In modern applications of power electronics, AC capacitors are among the most critical links in the chain of components when it comes to long operating life, safety and reliability of operation. Decades of proprietary ELECTRONICON experience in metallizing capacitor films and designing high-end capacitors have created our very own Know-How, for instance in special metallizing patterns, our SINECUT slitting technology and optimized winding geometries. This enables us to design AC capacitors with a high specific ratio of capacitance to volume, high AC-voltage load capacity and outstanding suitability for high rms and surge currents. The cylindrical capacitors of our universal AC/DC series "E62" are perfect for non-sinusoidal voltages and pulsed currents, e.g. as damping or commutation capacitors switched in parallel to a thyristor, or connected in series with a resistor (damping of undesirable voltage spikes during the switching of power semiconductors).

E57 are designed to fit directly to the terminals of your IGBT. Our range comprises standard as well as custom-tailored solutions which can be adapted to the specific geometrical and electrical requirements of your application environment. Connection is made through low-inductance copper bars which may vary in number, size and position according to your specifications. The UL:V0 plastic case houses compact and stable cylindrical windings, connected in parallel for maximum current strength and lowest possible selfinductance; it is filled with polyurethane resin, covered by a layer of UL94:V0 compliant resin protecting the winding package from humidity. Our highly reliable SecuMet™ film guarantees secure self-healing properties even under the most demanding operating conditions. Some of our E57 capacitors can be operated at ambient temperatures up to 105°C and are therefore suitable for usage in automotive and other critical applications

The capacitors of our SR17™ series were developed especially for the maintenance of older traction converters manufactured in the 1970s?1990s. By consequent development of our well-proven MKP-technologies, we managed to place self-healing DC-capacitors with very high energy density and stability of capacitance into can dimensions smaller than, or identical to, those of the traditional MP-capacitors (SIEMENS/EPCOS codes B25353), which makes them ideal drop-in replacements for maintenance and retrofit programmes. Moreover, the low-loss polypropylene dielectric permits a far higher AC ripple load than with the conventional MP-capacitors. Our SR17™ are housed in a hermetical stainless steel cylinder. As opposed to the oil-filled MP-models, these are filled with an eco-friendly solid resin which does not only make them safe against leakage of liquids but also insensitive to the shocks and vibrations common in traction applications. The same applies to their robust plastic insulators.

Thanks to the special kind of films and coating patterns used in our E56/E59-capacitors, clever winding geometries and refined internal construction, they unite large capacitance, very small self-inductance and high surge current sustaining capability (up to 700kA) as well as the possibility of high rms currents (up to 750A). Instead of flat pack windings, our capacitance is formed by compact cylindrical windings, avoiding the mechanical stress and instabilities at the edges of flat packs. Special terminals allow for additional reduction of the self-inductance. At the same time, they are extremely overvoltage-proof. They are especially suited for buffer storage circuits of converters, filter circuits and such like. The capacitors are housed in aluminium or steel cases and filled with solid resin which makes them absolutely dry and leakage-proof. Their shape and dimensions can be adapted to the individual requirements of our customers.

The special kind of films and coating patterns used in our oil-filled E63-capacitors give them a high specific ratio of capacitance to volume and makes them extremely overvoltage proof. Very good self-healing characteristics and the integrated overpressure protection (" BAM ") ensure safe operation and controlled disconnection in the event of overload or failure at the end of operating life. Hence the E63s are interesting particularly for applications with high AC ripple currents, e.g. as smoothing or supporting capacitors in buffer storage circuits, in sensitive environment with high safety requirements. Note that the presence of an overpressure mechanism adds substantially to the self-inductance of the capacitor, and limits the surge current rating. If self-inductance and surge current are important issues, then our E50 or E53 ranges may be considered as a more adequate option.

The PK16™ capacitor can be universally used for the assembly of low inductance DC buffer circuits and DC filters; with its high energy density it can replace banks of series-connected electrolytic capacitors as well as large film capacitors in rectangular cases. The capacitance in a DC buffer circuit must be sufficiently sized to both handle and smoothen the occurring ripple currents. The traditional use of series-/parallel-connected electrolytic capacitors offered large capacitance at seemingly low cost, however the low cost per microfarad is countered by the very low current strengh, the high sensitivity to voltage and current surges, as well as a substantial risk of failures in the field, resulting in high maintenance cost. Our advanced know-how in special capacitor film coating and many years of practical experience in designing and manufacturing capacitors have allowed us to develop our PK16™ range with high capacitance density.

E53 and E55 capacitors have a particularly low series resistance and high pulse strength. Using sophisticated metallizing patterns, our SINECUT slitting technology and clever winding geometries, they are especially suited for the damping of GTO thyristors and low-inductance buffer circuits with high rms currents. Along with their very good ratio of capacitance to volume, these components do also have very good self-healing characteristics without loss of capacitance. Their very low self-inductance makes them suitable for use in high-current applications with medium frequencies. The capacitors of the E53 product family are housed in flame-retardant plastic cans (V0) and filled with solid resin. Special care has been taken both in terms of design and conservative electrical rating to ensure reliable operation even under tough environmental conditions. Connection is usually made through robust axial terminals with internal thread.

AC capacitors require a hermetical casing in order to operate safely and without processes of chemical corrosion. The latter would result in deterioration of metal coating, decrease of capacitance as well as rise of loss factor and – consequentially – failure of the capacitor. DC capacitors – even though less sensitive to humidity – may suffer from excessive operating conditions as well. Another serious issue is the operation in conditions of extreme heat, and there are situations where placement in a cooling liquid is the only way. Certain high voltage applications may require the immersion of all components in insulation oil, such as MIDEL. Quite a few cooling or insulation oils behave aggressively towards metallized polypropylene, causing swelling of the film and deterioration of the contact layers. They must therefore be kept away from the capacitor elements. In the past, mostly MKV capacitors (with oil-impregnated paper electrodes) had to be used in such situations.