27,5-35kV Three-phase oil-immersed power transformers ТМ, ТМГ type

TECHNICAL DATA OF THE TRANSFORMERS

  The marking structure for ТМ, ТМГ type transformers: 

ТМ, ТМГ - ХХХХ / ХХ  У1:

• Т – three-phase transformer.
• М – cooling with natural circulation of oil and air.
• Г - transformer hermetically sealed (no expansion tank).
• ХХХХ – transformers rated power,  kVA.
• ХХ – the voltage class of HV winding, kV.
• У(УХЛ)1 – climatic version У(УХЛ) and allocation category 1 (ГОСТ 15150-69).

The transformers has a backbone with three-rod-core laminated magnetic system, assembled of cold-rolled electric steel sheets using "Step-Lap" technology. The windings are cylindrical-shape, are placed on core rods concentrically. The tank of a power transformer is equipped by fittings for filling, sampling, filtering and draining of the transformer oil, as well as for connecting a cooling system and vacuum pump.

Transformers are suitable for indoor and outdoor use and for use in the following conditions:

- altitude up to 1000 m;

- temperate and cold climates - У1 (УХЛ1);
- Operating temperature range: from -45°C (У1) or -60°C (УХЛ1) to +40°C
Transformers are not suitable for use in the following conditions:
- In the explosive and corrosive medium (containing gases, vapors, dusts and others in an increased concentration);
- Vibration or shock;
- With frequent on-load reconnections on the feeding side.

Transformers are equipped with:
- Oil-level indicator. Designed to control the oil level in the expansion tank;
- Thermometer. Designed to control the temperature characteristics of the transformer. By default, are set to the transformers with rated capacity 1250kVA or more;
- Gas relay. Designed for visual inspection of the evolved gas. By default, are set to the transformers with rated capacity 1600kVA or more;
- Rollers. Designed for relocation the transformers in longitudinal and transverse direction. By default, are supplied with the transformers of 1000 kVA  capacity and above;
- Contact terminals (LV side). Designed for LV side easy connection by the customer. By default, are supplied with the transformers of 630 kVA and above.
The transformer provides voltage regulation, with control range ± 2x2.5% of the rated voltage. Type of control - ПБВ (switching without excitation). Switching the transformer to another level should be operated in off-load mode.
Upon customers request, accessories can be added or changed.
The design of the transformer
The transformer consists of the following units:
- The transformer tank;
- The active part rigidly attached to the cover;
- Entries;
- Oil conservator;
- Dehumidifier;
- Protective and control devices
  Transformer tanks are made with welding connections, has rectangular shape and made of a corrugated cheeks providing volumetric expansion of the oil at different ambient temperatures. The corrugated cheeks are cooling elements (the tanks with radiators can be manufactured on customers request).
  The cover is rectangular. HV, LV entries, ПБВ switch, expander control devices are mounted on the cover.
  The active part consists of a core, LV winding, HV winding.
The frame consists of a magnetic core, upper and lower yoke is pulled yoke beams. The three-rod magnetic core is made of cold rolled electrical steel using "Step-lap" blending scheme.
LV and HV windings are made of aluminum wire (copper wire on request).
Since permanent inmrovements involving to our transformers, LV windings can be made of aluminum foil.
Transformers are compliant to TУ 31.1-13608660-062: 2007
Transformers made according to ГОСТ 11677, 11920.