Profile Metallization
Summary matrix of the types of metallization:
Types of metallization
- 1. Constant Resistance
Metallized layers with constant resistance can be made with purest aluminium or zinc with a variable share of aluminium. Our process is capable of evaporating even large areas with an evenly distributed metal layer with the help of mathematical simulation models.
- 2. Heavy-edge (RV)
"Heavy-edge" is the classical solution to enable a stable and low resistive contact to the end-spray (shoop) of the capacitor.
We offer a wide range of choices regarding the metal ratio between the surface resistance of the heavy-edge and the active area.
- 3. Profile Metallization, Wide Heavy-Edge
The best possible compromise and optimisation on low electrical losses and high break down voltages can be achieved by combining a wide heavy-edge with high Ohms on the surface at the free margin side. A wound capacitor must always have one of the two films with a good self-healing behaviour using a high resistive area; typically 1/3 low resistivity and 2/3 high resistivity are designed over the film width.
In collaboration with our customers we precisely define the resistance profile by a drawing.
- 4. Profile Metallization, soft transition, linear resistance
Metallization, with a defined profile of the surface resistance (= Rs), allows the minimisation of the losses at each and every single point inside the capacitor (Pr = I² Rs).
During the design phase the tan. δ, self-healing and breakdown voltage can be rated and optimised mathematically. A profile drawing with the precise resistance profile will then be provided to our customer.
Remarks:
The sketches symbolise the metallized layers of aluminium (yellow) and zinc (red). In the profile drawings provided by us the surface resistance is normally illustrated reciprocally.