Because the dry-type transformer made of NOMEX paper as insulating material is not easy to burn, and the energy released during combustion is much smaller than that of epoxy resin dry-type transformer, it is easy to meet the internationally recognized combustion test requirements. After the dry-type transformer is scrapped at the end of its service life, the treatment and recovery of its insulating material degradation material will also better meet the requirements of environmental protection than epoxy resin. Therefore, it can be considered that the environmental performance of NOMEX paper is much better than that of epoxy resin, and it is more suitable for use in countries and regions with high environmental requirements.
1. The iron core is made of cold-rolled silicon steel sheet with high magnetic conductivity grain orientation (CRGO), fully inclined and holeless binding, and has a built-in pull plate structure, which is beautiful and clean in appearance, low no-load loss and low noise.
2. The high voltage coil is of continuous structure, with good heat dissipation, which makes the overload capacity of the transformer stronger. The low voltage coil is of foil type, which enhances the stability of the coil and improves the short-circuit resistance; The coil adopts a unique vacuum pressure impregnation H-class flame retardant paint, and is cured at high temperature. The surface can be dustproof, moisture-proof and antifouling.
3. In order to reduce the vibration and noise of the transformer, the iron core and coil, the iron core and clamp, and the support are all placed with high-voltage elastic silicone rubber elements.
4. Hengfengyou Electric can provide protective enclosure, air cooling device and thermal protection device according to user needs.
5. Contact us for more information about Hengfengyou NOMEX dry-type transformer（ hfy@hengfengyou.com )。
3、 Comparison between Hengfengyou NOMEX paper insulated dry-type transformer and Hengfengyou electric epoxy resin cast transformer:
1. The most outstanding advantage of Class H OVDT dry-type transformer is its strong overload capacity. This is due to its thin insulation layer, good ventilation and heat dissipation, and small difference between the maximum temperature rise and the average temperature rise. For products made of NOMEX paper, it also uses the insulation temperature between Class C materials (220 ℃) and Class H products (180 ℃).
2. Class H OVDT dry-type transformer has good thermal shock resistance and can effectively prevent cracking.
3. The coil repair of OVDT products is relatively easy.
4. From the energy released during combustion, the epoxy casting type is much larger.
5. From the perspective of environmental protection performance, epoxy casting is not as good as Class H OVDT, especially in the degradation treatment and recovery.
6. The moisture-proof property of Class H products with VPI process can reach the high quality level under the condition of complete manufacturing process.
7. Under the condition that the quality of materials and technology is guaranteed, the partial discharge level of Class H OVDT dry-type transformer is roughly equal to that of epoxy casting type.
8. In principle, the size and quality (weight) of Class H products can be smaller than that of Class F.
9. From the perspective of the development requirements of dry-type transformer technology, in the new draft of IEC60076-11 standard, it is proposed that three tests must be carried out in the future: fire resistance (F), environmental adaptability (E) and thermal shock resistance (C). From the perspective of meeting these three tests, Class H OVDT dry-type transformer is more advantageous than epoxy casting type.
4、 Certification of NOMEX paper-insulated dry-type transformer by authority
1. NOMEX paper-insulated dry-type transformer is the only dry-type transformer below 35 kV certified by UL of the United States and CSA of Canada.
2. NOMEX paper-insulated dry-type transformer is the only dry-type transformer that meets the most authoritative European standards CENELEC, NCRM and HD464 in terms of fire protection and climate adaptation.
3. NOMEX paper-insulated * was recognized in 1992 to meet the highest quality and fire protection standards of EDF in France. "
*NOMEX paper, also known as Nome paper, is a synthetic aromatic amide polymer insulating paper with high mechanical properties, flexibility and good electrical properties, and can maintain its characteristics at high temperatures. It is widely used in generators, transformers, electrical equipment, electromechanical and household appliances.
