100 MVA High Voltage Power Transformers-132/22 kV | Malaysia 2023

Power transformers – the heart of stable energy and the backbone of a robust power grid! 

01 General

1.1 Project Description

Two 100 MVA 132kV power transformers were delivered to Malaysia in December 2023. The two 100 MVA high voltage power transformers were supposed to be used in the TikTok data center in Malaysia. The rated power of this power transformer is 100 MVA with ONAN/ONAF cooling, the high voltage is 132 kV with +7×1.5% to -17×1.5% tapping range(OLTC), the medium voltage is 33 kV with ±2×2.5% tapping range(NLTC), and the low voltage is 22 kV. The two 132kV main transformers, using the company’s model for the SFSZ-100000/132 three-coil air-cooled on-load voltage regulator transformer, they formed a vector group of YNd1d1.

The 100 MVA high voltage power transformer is a robust and reliable electrical device designed to transfer electrical energy between different voltage levels efficiently. Our power transformers are manufactured using high-quality materials and state-of-the-art technology to ensure optimal performance and long-term durability. In 2025, our client placed another order for the same specifications, choosing the 100 MVA large power transformers for their new data center project, demonstrating continued trust in our products and services.

We ensure that each one of our delivered units has undergone rigorous full acceptance testing. We provide one-package service from consulting, quoting, manufacturing, installation, commissioning, training to after sale services, our products are now operating in more than 50 counties in the world. We aim to be your most reliable supplier as well as your best partner in business!

1.2 Technical Specification

100 MVA high voltage power transformers specification and data sheet

1.3 Drawings

100 MVA high voltage power transformers diagram drawing and size.

02 Manufacturing

2.1 Core

The iron core is made from high-grade, grain-oriented silicon steel laminations, which are stacked and tightly bound together to form a solid core. The use of such materials is essential for reducing energy loss due to eddy currents and hysteresis. The primary function of the iron core is to provide a low-reluctance pathway for the magnetic flux generated by the transformer’s primary winding. This magnetic flux induces a voltage in the secondary winding, thus facilitating the efficient transfer of electrical energy from one circuit to another.

2.2 Winding

The windings of the two high voltage power transformers are continuous, high mechanical strength, good heat dissipation performance, with 1 to 6 flat wires on the strut and wound into a cake line segment. Cake with oil or oil channel and paper ring crisscross separated, both ends of the oil channel and insulation ring.

2.3 Tank

The transformer tank is made of welded steel plates and reinforced to provide mechanical strength and protection to the internal components of the transformer to withstand transport, handling and overpressure under fault conditions without distortion. When the transformer is working normally, the oil tank base can be checked without using any special tools. In order to ensure the safety of personnel, during the normal loading period, the ambient temperature is 40 ° C, the maximum temperature of the tank surface (where people can reach) is 70 ° C.

2.4 Final Assembly

The final assembly of high voltage power transformers includes the integration of components such as iron core, winding and insulation structure to form a complete transformer device. The process includes the following steps: Core Assembly: assembling the core components together, and stacking high-grade silicon steel sheets to provide efficient magnetic circuits and reduce energy losses. Winding Assembly: the installation of winding coils on the core, including primary and secondary windings, requires precise process and insulation to ensure electrical performance and safety. Tank structure assembly: this involves assembling the tank, radiator, and cooling system into a complete housing to provide good protection and isolation. Insulation Structure: assemble protection and insulation structure to ensure that windings and other key components are protected and isolated. Oil filling device: ensure that the transformer is cooled and insulated by injecting insulating oil into the oil tank.

03 Testing

a) The following tests shall not be carried out until the physical examination and the pre-handover test have been carried out in accordance with the requirements.

b) No-load test and no-load impact closing test (the cooler is not in operation)

① The transformer should be connected to the voltage from the power side, because the power side is equipped with protective devices to ensure that the power is cut off in an abnormal situation.

② Switch the signal contacts of the gas relay of the transformer to the tripping circuit of the transformer power supply.

③ The time limit of overcurrent protection is set as instantaneous action.

④ After the transformer is connected to the pressurized line, the voltage should be slowly increased from zero to the rated voltage for 1h, during which the transformer should not have any abnormal phenomenon.

⑤ After the above test, the voltage should be gradually increased to 1.1 times the rated voltage, and no abnormal phenomenon should be maintained for 10 minutes, and then gradually reduced. If the site does not have the conditions for slowly increasing pressure, it can be changed to no-load 1h test run, when the top oil temperature is lower than 42 ° C, do not start the radiator fan or do not put the cooler.

⑥ For the on-load regulator transformer, the on-load tap-changer is electrically operated at the rated voltage for two weeks and finally adjusted to the rated tap-changer position.

⑦ No-load impact closing test.

04 Packing and Shipping

4.1 Packing

1. Use strong wooden case as outer packing, and install shock-proof material in case, such as foam, air cushion, to reduce the impact of vibration and impact on the product. 2. Protect the transformer itself, including the components of the transformer, to prevent vibration and external environment on the impact of the product. 3. Clearly mark the weight, size, port of destination address and contact information on the package.

4.2 Shipping

1. We choose sea transportation because it can accommodate large equipment and provide a relatively stable transportation environment. 2. In selecting carriers, we choose experienced and professional logistics companies to ensure that products can safely and timely arrived at the destination, and complete the customs clearance.

05 Site And Summary

Preparation: Check the foundation and equipment condition, test insulation, and prepare lifting tools.

Lifting: Lift using designated points, level the transformer, and secure bolts.

Accessories: Install bushings, radiators, and other components, ensuring proper sealing and fastening.

Oil Filling: Use an oil purifier for vacuum oil filling, check oil level, and sealing.

Testing: Conduct insulation, ratio, no-load, and short-circuit tests.

Grounding: Install grounding system and test resistance.

Commissioning: Verify installation, perform gradual load testing, and put into operation if no issues occur.