Resin-Insulated Dry-Type Transformer

Overview

The resin-insulated dry-type transformer is developed by Gaosuo Electric Co., Ltd. on the basis of advanced foreign technology, covering the SC9, SCB9, SC10 and SCB10 series of thin-insulation dry-type transformers with filler. The windings are encapsulated with epoxy resin, making the unit flame-retardant, fire-proof, explosion-proof, maintenance-free, pollution-free and compact, so it can be installed directly at the load center. With a scientific design and casting process, the product features lower partial discharge, low noise and strong heat dissipation; under forced-air cooling it can operate continuously at 140% of rated load, and is equipped with an intelligent temperature controller providing fault alarm, over-temperature alarm, over-temperature trip and black-box functions, with an RS485 serial interface for centralized monitoring and control via computer. Owing to these advantages, the resin-insulated dry-type transformer is widely used in power transmission and distribution systems such as hotels, airports, high-rise buildings, commercial centers and residential communities, as well as in harsh environments like subways, smelting plants, ships and offshore drilling platforms. The SC(B)9 series covers rated capacities from 10 kVA to 4000 kVA.

Type Designation

Core

The core is made of imported high-quality cold-rolled silicon steel sheets with a full-step-lap joint structure; the core limb is bound with F-class non-woven tape, and the core surface is encapsulated with epoxy resin, reducing no-load loss, no-load current and core noise. Clamps and fasteners undergo special surface treatment, which further improves the appearance quality of these resin-insulated dry-type transformers.

HV Winding

The HV winding is vacuum-cast with filled epoxy resin, greatly reducing partial discharge and improving the dielectric strength of the coil. Glass-fiber mesh plates fill the inner and outer walls of the winding, enhancing its mechanical strength and short-circuit-withstand capability, so the coil never cracks. The SC(B)9 series uses this cast-resin HV winding construction to keep partial discharge low over the whole service life.

LV Winding

The LV winding adopts a foil structure, eliminating the axial helix-angle problem of wire winding and balancing the ampere-turns. Axial cooling ducts in the coil enhance heat dissipation, and DMD epoxy pre-impregnated fabric is used between winding layers for integral curing.

Manufacturing Process

The coils are wound on high-precision winding machines, with the LV winding in foil structure. Ventilation ducts are provided for larger-capacity transformers. After winding, vacuum drying is carried out; the entire casting and curing process strictly follows the process requirements with rigorous monitoring and adjustment as needed. This precision casting process yields bubble- and cavity-free coils, enabling the resin-insulated dry-type transformer to achieve excellent service performance.

Temperature Control and Forced-air Cooling System

A cross-flow top-blowing cooling fan is adopted, featuring low noise, high wind pressure and an attractive appearance, which enhances the overload capability of the transformer. Intelligent temperature control further improves the operational safety and reliability of the transformer. The SC(B)9 series is rated for 10 kV class systems with F/F insulation class.

• SC(B)-9-□/□
• Rated voltage (HV, kV)
• Rated capacity (kVA)
• Performance level code
• LV foil winding
• Solid cast (epoxy resin cast)
• Three-phase

Technical Parameters (10kV Class SC(B)9 Series)

Related Products

Transformers of the same series and other types available for selection:

• 10kV Oil-Immersed Distribution Transformer