146 MVA BESS Application Transformer

  • Primary Voltage Ratings: 66 kV
  • Secondary Voltage Ratings: 33 kV
  • H.V. TAP RANGE: -10 % to +15 %
  • TYPE: Sealed Power Transformer
  • Standards: AS
  • Application: Battery Energy Storage System
  • Power Rating: 146 MVA
  • Cooling Method: ONAN

The 146 MVA transformer is specifically engineered for Battery Energy Storage System (BESS) power stations. Designed with a double-split configuration, it mitigates electromagnetic interference and circulating currents, thereby reducing harmonics and enhancing power quality. With an IP56 protection rating, it is suitable for outdoor installation and can operate within a maximum 72.5 kV system.

Quote Now
Rating 146 / 73 / 73 MVA
Phase 3
Frequency 50 Hz
Nominal primary voltage 66 000 V
Nominal secondary voltage 33 000 V / 33 000
Vector group YN0d11d11
Impedance 12.0%
Operating mode Duty
Location Outdoor
Degree of protection  IP56
Full load temperature rise  65℃
Mean sound level at 1 metre 70.2 dB
Harmonics compliance As per design

Contact Daelim Transformer for special requirements

 

System highest voltage - primary 72.5 kV
System fault level - primary TBC
Method of earthing - primary Solid
System Highest Voltage - Secondary 36 kV
System fault level - secondary 1000 A (TBC)
Method of earthing - secondary Impedance Earthed
Core 1 - Differential CT - Set 1 300-1000/1A 0.06PX600R3.5 AT 1000/1A
Core 2 - Differential CT - Set 2 300-1000/1A 0.06PX600R3.5 AT 1000/1A
Core 3 - Metering CT 300-1000/1A 0.5M 15VA
Core 4 - Feeder CT - Set 2 300-1000/1A 0.06PX600R3.5 AT 1000/1A
Core 5 - Feeder CT - Set 1 300-1000/1A 0.06PX600R3.5 AT 1000/1A
Secondary CT - WTI As per design
Type OLTC on Primary winding
Tapping Range -10 % to +15 %
Principal tap 66,000 V
Number of tap positions 21
Change per step 1.25%

The transformer featuring a sealed tank and layered winding structure crafted from copper, ensures durability and reliability. Equipped with an on-load tap changer at high voltage, it allows for seamless voltage adjustments without interrupting power supply or load equipment operation. With 21 gear settings, each providing a voltage adjustment value of 1.25%, the transformer offers a range of voltage adjustments from -10% to +15% of the rated voltage value, adapting flexibly to line voltage fluctuations.

The transformer is equipped with an externally readable oil level gauge featuring a low oil level alarm and trip mechanism, along with an oil temperature gauge incorporating a high oil temperature alarm and trip function. Additionally, it includes winding temperature RTDs and an oil temperature gauge with winding temperature alarm and trip capabilities. An automatic pressure relief device is also integrated into its design. Moreover, the main oil tank is fitted with a Buchholz relay for enhanced safety and monitoring.

With an A-class insulation level, the primary side of the transformer boasts an insulation level of 72.5 kV (rms), a power frequency withstand voltage of 140 kV (rms), and a lightning impulse withstand voltage of 325 kV. Similarly, the secondary insulation level is rated at 36 kV (rms), with a power frequency withstand voltage of 70 kV and a lightning impulse withstand voltage of 170 kV.

Related Products

DOE
AS
GOST