SC (B) 11-50-2500kVA/10kV dry transformer series epoxy resin cast dry-type transformer

Model Meaning

Product Features

High insulation strength: The epoxy resin used for casting has an insulation breakdown field strength of 18-22kV/mm, and has approximately the same lightning impulse strength as oil immersed transformers with the same voltage level. The insulation temperature level is F level, with a maximum allowable temperature of 155 ℃ and a winding temperature rise limit of 100K.

Strong short-circuit resistance: Due to the material properties of the resin and the fact that the winding is cast as a whole, it becomes a rigid body after heating and curing, resulting in high mechanical strength. Through sudden short-circuit tests, it has been proven that very few dry-type transformers are damaged due to short circuits.

Outstanding disaster prevention performance: Epoxy resin is flame retardant, flame-retardant, and can self extinguish, without causing secondary disasters such as explosions.

Superior environmental performance: Epoxy resin is a chemically extremely stable material that is moisture-proof and dustproof. It can operate reliably even in harsh environments such as atmospheric pollution, and can even operate normally at 100% humidity. After shutdown, it can be put back into operation without drying or preheating.

Maintenance free: With a comprehensive temperature control and temperature display system, epoxy cast dry transformers can now achieve maintenance free operation, greatly reducing the burden on operators and lowering operating costs.

Low operational losses and high operational efficiency.

Low noise.

Small size, light weight, easy installation and debugging.

No need for a separate transformer room, no need for core inspection, saving floor space and corresponding civil engineering investment, with strong overload capacity.

We can provide H-grade insulation products according to user requirements.

core

The iron core is made of high-quality cold-rolled silicon steel sheets, with a 45 ° fully inclined joint structure. The core column is tied with insulating tape, and the surface of the iron core is sealed with insulating resin paint to prevent moisture and rust. The clamps and fasteners are surface treated to prevent rust.

High voltage casting coil

Main materials and characteristics:

The coil uses F-grade insulated copper wire as the conductor, and glass fiber and epoxy resin composite material as the insulation. Its coefficient of expansion is similar to that of copper conductor, and it has good impact resistance, temperature change resistance, and crack resistance. All components of glass fiber and epoxy resin have self extinguishing properties, do not sustain combustion, and do not produce toxic gases or pollute the environment. Epoxy resin has good insulation properties and is particularly suitable for making high-voltage coils.

manufacturing process

The coil is wound on a high-precision winding machine. During winding, fiberglass is laid on the inner and outer layers of the coil, and ventilation ducts are designed when the transformer capacity is large. After the coil winding is completed, it is vacuum dried. The entire pouring and solidification process can be monitored at any time on the computer terminal and automatically adjusted by the computer according to the situation. Make the coil free of bubbles and voids.

Low voltage foil coil

For low voltage and high current coils. The short-circuit stress during short circuit is relatively high, and the number of low-voltage turns is small. The larger the low-voltage current, the more prominent the problem of unstable ampere turns when using wire winding type, and the heat dissipation problem also needs to be considered. At this time, using foil winding for low voltage can better solve the above problems. Firstly, foil products do not have axial turns or axial winding helix angles, and the high and low voltage windings have balanced turns, resulting in less axial stress on the transformer during short circuit. Secondly, due to its thin insulation, it is easy to set up multiple layers of air ducts in the process, which also solves the heat dissipation problem. The low-voltage foil coil is wound on an automatic foil winding machine and welded internally using argon gas protection welding on the winding machine, with high precision, low welding resistance, and no external welding process. DMD insulation is used between winding layers, and the rear end is sealed and cured with resin after winding.

Transformer outgoing line method

Distribution transformers can be manufactured with conventional outgoing lines, standard enclosed busbar outgoing lines, and standard side outgoing lines according to different interface forms, and special outgoing lines can also be designed according to user requirements.

Product standards

JB/T 3837-2010     GB 1094.11-2007

Fixed high voltage: 10 (10.5, 11, 6, 6.3, and 6.6) kV

Rated low voltage: 0.4kV

Tap range: Non exclusion voltage regulation: (± 5%, ± 2 × 2.5%)

On load voltage regulation: (± 4 × 25%)

Connection group: D yn11   or  Y yn0

Insulation level: L175AC35/AC5

Technical Parameter

SC (B) 11 10kV epoxy resin cast type non excited voltage regulating distribution transformer