Metallization for Inner Series Patterns
Series circuits of capacitors are not only realisable by discrete components but also directly integrated into the metallization. A compact capacitor wound element can be achieved, suitable for the highest operating voltages, using a detailed pattern of free margins.
An inner series design is generally the ideal solution if:
- the increase of the operating voltage of the capacitor is limited by the thickness of the dielectric material (film thickness not available, too high field stresses at edges and surfaces)
- the field stress (V/µm) of the dielectric material is to be limited, e.g. to avoid corona discharge safely
Steiner offers a wide spectrum of free margin sequences, in band or oil masking technology, that can be combined with every metallizing type plus segmented lines.
2-fold series patterns are normally symmetrically laid out and typically wound by using one film with a centre margin and the other film with margins on both sides.
Multiple series patterns require a precise calculation, including the winding off-set, to ensure the voltages inside the capacitor are spread equally.
The example above represent a 13-fold series pattern of a film width of 120mm.
The margin sequence:
F2-M16-F2-M16-F2-M16-F2-M16-F2-M16-F2-M16-F2-R10 = 120mm
results in part capacities of an active area of each 7mm.
We will gladly support you during the design of series patterns for your applications.