Vacuum impregnation
High dielectric performance at reduced thickness
A transformer operating in high-frequency applications has two opposing requirements:
- effective coupling between the windings, to minimize stray inductance; this implies placing the windings as close together as possible;
- effective insulation between the windings, to create a galvanic barrier between the two circuit potentials; this requires the introduction of insulating materials between the windings, increasing the distance between them, negatively affecting stray inductance.
Sirio achieves an optimal balance between these two targets, minimizing the thickness of the insulating barrier thanks to the selection of suitable materials and vacuum impregnation of the components.
Dedicated additional high-temperature treatments of the component complete this strategic technology, which is implemented in five resin-treating plants.
Thanks to this technological expertise, Sirio can achieve insulation levels of up to 20 kV/mm.
automation
Features consistency
In high-frequency applications, mechanical consistency is crucial: even a slight misalignment of turns can result in variations in coupling between windings. This leads to differences in electromagnetic behavior from one transformer to another, potentially causing unpredictable converter performance.
Even highly skilled operators cannot maintain the same level of mechanical precision throughout an entire workday when using manual winding machines, since winding accuracy depends heavily on individual skill.
From the very beginning, Sirio recognized that automation was the winning strategy to ensure consistent mechanical precision and repeatable product quality.
Automated machines are computer-controlled, eliminating potential errors such as incorrect turn counts or improper insulation layering. They also ensure precise wire connection to output pins, automatically monitoring soldering quality.
In addition to improving product quality, a high level of automation reduces production time and provides significant cost advantages.
100% testing
Long-term reliability
Our transformers are used in industrial equipment that must operate for years.
The reliability of Sirio transformers is achieved through a combination of several factors:
- high-quality raw materials;
- step-by-step testing during production;
- 100% final inspection.
Two other important elements positively influence reliability:
- the use of certified procedures during design, production, and testing (Sirio has been ISO 9001 certified since the early 1990s);
- the absence of partial discharges in the insulation within the transformer’s operating voltage range.
Partial discharges damage the insulation over time and cause internal short circuits. Our vacuum casting technology eliminates air cavities and therefore partial discharges in the insulation layers.
Sirio also has instruments capable of detecting partial discharges at test voltages up to 30 kV.
