110kV Customized 12500kVA 20000kVA High-Voltage Electric Power Transformer
The Customized 12500kVA and 20000kVA High-Voltage Electric Power Transformer is engineered to meet the demanding requirements of grid transmission, industrial distribution, and large-scale power infrastructure. Designed with fully customized voltage configurations, high-grade copper windings, advanced insulation systems, and optimized oil-immersed cooling structures, it ensures exceptional efficiency, stable voltage regulation, and long-term operational reliability. This transformer supports heavy-load operation, complex grid environments, and diverse installation conditions, making it suitable for substations, industrial plants, renewable energy integration, and major commercial facilities. With flexible design options, strict quality control, and compliance with international standards such as IEC, IEEE, and ANSI, it delivers robust performance and extended lifecycle.
- Primary Voltage Ratings 110kV, 115kV or others
- Secondary Voltage Ratings 11/10.5/6.6/6.3kV or customized
- H.V. Tap Range ± 8×2.5% HV taps or others
- Type Oil-immersed power transformer
- BIL up to 350kV
- Standards IEEE, ANSI, IEC
- Application utility substations, industrial power distribution networks, renewable energy plants
- Power Rating 12500kVA 20000kVA
- Certificate UL , CESI , CE
- Cooling Method ONAN/ ONAF
- Opeartion Step Down & Step Up
Technical Specifications
Customization Optional
Packing and Shipping
Manufacturer Test
Routine Testing
Application
Technical Specifications
110kV Customized 12500kVA 20000kVA High-Voltage Electric Power Transformer
Technical Specifications
Accessories
| Rated Power | 12500kVA 20000kVA |
| Rating Primary Voltage | 110kV, 115kV |
| Secondary Voltage |
6.3 kV 6.6 kV 10.5 kV 11 kV Customized |
| Frequency | 50/60Hz |
| Vector Group | Dyn11, YD11, YNd11 |
| Winding Material | Aluminum/Copper |
| Efficiency | As IEEE, CAS Std or Customized |
| Impedance Voltage | As IEC |
| Altitude | ≤1,000m or Customized |
| Enclosure material | Mid Steel |
| HV Bushing |
| LV Bushing |
| OLTC/NLTC |
| Lifting hook for complete transformer |
| Name plate |
| Oil temperature |
| Winding temperature |
| Radiators |
| Oil level |
| Pressure relief valve |
| CT |
Customization Optional
110kV Customized 12500kVA 20000kVA High-Voltage Electric Power Transformer
Our Customized 12500kVA and 20000kVA High-Voltage Electric Power Transformers offer full flexibility in electrical, structural, and material configurations to meet diverse grid and industrial requirements. Clients can specify primary and secondary voltage levels across a wide range, insulation class, vector group, impedance selection, cooling method (ONAN/ONAF/OFAF), and advanced protection features. Winding materials are available in high-conductivity copper or aluminum, depending on load characteristics and budget preferences. The core can be customized using high-permeability grain-oriented silicon steel or premium-level amorphous alloys for enhanced energy efficiency. Additional options include reinforced insulation systems, low-noise magnetic designs, enhanced dielectric strength, and compact or extended tank structures to suit site limitations.
Mechanical customization options include weatherproof enclosures, seismic-resistant structures, anti-corrosion surface treatment, HV/LV bushing specifications, customized radiators, and integrated monitoring devices such as DGA sensors, temperature controllers, OLTC monitoring systems, and IoT-based smart transformer modules. Customers may also choose custom accessories, including tap changer types, oil purification systems, protection relays, and terminal configurations. All transformers can be built to comply with IEC, IEEE, ANSI, GOST, or customer-specific technical requirements. Our engineering team works closely with clients throughout design, simulation, prototyping, and manufacturing to ensure exact performance alignment and long-term operational reliability.
Packing and Shipping
110kV Customized 12500kVA 20000kVA High-Voltage Electric Power Transformer
All Customized 12500kVA and 20000kVA High-Voltage Electric Power Transformers are packaged using heavy-duty, export-grade protective materials to ensure maximum safety during transportation. Before packing, each transformer undergoes oil draining (if required), mechanical locking of moving parts, and sealing of all air passages. The transformer tank is coated with anti-corrosive paint, and all external components are securely fastened. High-voltage bushings, radiators, conservators, and control cabinets can be packed separately in wooden crates lined with moisture-proof materials to prevent vibration or damage during transit.
For long-distance shipping, transformers are typically mounted on reinforced steel skid bases or heavy-duty pallets to support their weight and maintain stability. Shock-absorbing pads are applied at critical contact points, and the entire transformer is wrapped with heat-sealed protective film and waterproof coverings. Humidity indicators and desiccants are placed within the packing area to ensure insulation and metallic components remain protected under fluctuating environmental conditions. Clear labeling, lifting guides, and handling instructions are applied on all sides, complying with international transport codes.
We coordinate land, sea, and multimodal shipping methods depending on the destination and project schedule. For overseas deliveries, transformers are transported in open-top containers or via bulk shipping, depending on dimensions and weight. All units are secured using heavy-duty chains, locking beams, and support brackets to prevent shifting during transit. Our logistics team manages route planning, loading supervision, port handling, customs clearance, and delivery to ensure seamless transportation.
Upon arrival, on-site unpacking and inspection guidelines are provided to the customer. Detailed installation manuals, test reports, and component lists accompany every shipment. Optional services include on-site supervision, unloading assistance, oil filling, and commissioning support. With our rigorous packing and shipping procedures, every Customized 12500kVA and 20000kVA transformer arrives safely and ready for installation in demanding operational environments.
For long-distance shipping, transformers are typically mounted on reinforced steel skid bases or heavy-duty pallets to support their weight and maintain stability. Shock-absorbing pads are applied at critical contact points, and the entire transformer is wrapped with heat-sealed protective film and waterproof coverings. Humidity indicators and desiccants are placed within the packing area to ensure insulation and metallic components remain protected under fluctuating environmental conditions. Clear labeling, lifting guides, and handling instructions are applied on all sides, complying with international transport codes.
We coordinate land, sea, and multimodal shipping methods depending on the destination and project schedule. For overseas deliveries, transformers are transported in open-top containers or via bulk shipping, depending on dimensions and weight. All units are secured using heavy-duty chains, locking beams, and support brackets to prevent shifting during transit. Our logistics team manages route planning, loading supervision, port handling, customs clearance, and delivery to ensure seamless transportation.
Upon arrival, on-site unpacking and inspection guidelines are provided to the customer. Detailed installation manuals, test reports, and component lists accompany every shipment. Optional services include on-site supervision, unloading assistance, oil filling, and commissioning support. With our rigorous packing and shipping procedures, every Customized 12500kVA and 20000kVA transformer arrives safely and ready for installation in demanding operational environments.
32
32 years of industry experience
Manufacturer Test
110kV Customized 12500kVA 20000kVA High-Voltage Electric Power Transformer
Progress test
During the progress test of the Customized 12500kVA and 20000kVA High-Voltage Electric Power Transformer, multiple evaluations are conducted throughout the manufacturing cycle to ensure compliance with design specifications. Core lamination verification, winding process inspection, insulation dimension checks, and clamping force assessments are performed at each key stage. Intermediate electrical tests include winding resistance measurement, turn ratio verification, insulation resistance checks, and partial discharge evaluation. Mechanical components such as tank welding seams, bushing assemblies, and radiator structures are also inspected for structural integrity and dimensional accuracy. Oil quality tests and OLTC functional checks are completed prior to final assembly. The progress test ensures that every essential component meets the required standards before the transformer enters final testing and commissioning.
Design Tests
All transformers will be tested after finishing the production test items as below:
♦ Leak testing with pressure for liquid-immersed transformers
♦ Test of transformer oil
♦ Measurement of voltage ratio and check of phase displacement
♦ Measurement of winding DC resistance
♦ Measurement of d. c. Insulation resistance between each winding to earth, and check of the core and frame insulation
♦ Capacitive bushing test
♦ Measurement of dissipation factor (tan δ) of the insulation system capacitances, and determination of capacitances windings-to-earth
♦ Measurement of no-load loss and current at 90%,100%,110% of rated voltage
♦ Operation test on on-load tap-changer
♦ Measurement of short-circuit impedance and load loss
♦ Lightning impulse test
♦ Induced-voltage test with partial discharge measurement
♦ Auxiliary wiring check
♦ Current transformer test
♦ Frequency response analysis test
Transformer Factory Acceptance Test
The Factory Acceptance Test (FAT) for the Customized 12500kVA and 20000kVA High-Voltage Electric Power Transformer includes a comprehensive set of tests performed in accordance with IEC and IEEE standards. Routine tests include applied voltage, induced voltage, insulation resistance, turn ratio, polarity, no-load loss, load loss, impedance voltage, and partial discharge measurement. Special tests such as lightning impulse tests, temperature rise tests, and sound level checks are conducted based on customer requirements. The OLTC undergoes full operational simulation under different tap positions. Mechanical inspections verify tank pressure strength, oil leakage resistance, bushing alignment, and cooling system performance. All results are documented in detailed FAT reports for customer approval prior to shipment.
Routine Test - Transformer Turns Ratio/TTR (All Tap Voltages)
Purpose of Testing
The purpose of the transformer turns ratio (TTR) test is to confirm whether the voltage ratio between each tap of the transformer meets the design requirements and ensure that the transformer winding is connected correctly. By measuring the voltage ratio of each tap, it is possible to detect whether there is a fault or deviation in the transformer winding.
Testing Equipment
TTR tester: such as Doble, Megger, Omicron and other brands of transformer winding ratio tester.
Voltage source: usually AC 10 V to 30 V , used to test different voltages for each tap.
Temperature and humidity meter: used to record environmental conditions during the test to ensure test accuracy.
Current probe: used to measure the load current of the winding and ensure the accuracy of the test results.
Voltage source: usually AC 10 V to 30 V , used to test different voltages for each tap.
Temperature and humidity meter: used to record environmental conditions during the test to ensure test accuracy.
Current probe: used to measure the load current of the winding and ensure the accuracy of the test results.
Pre-Test Preparation
Disconnect all transformer tap-changers from the power supply and ensure that all equipment is properly grounded and discharged.
Perform the test under suitable environmental conditions: relative humidity below 75% and no rain (recommended temperature: 20-30°C). Avoid high humidity or bad weather that may affect the test accuracy.
Perform the test under suitable environmental conditions: relative humidity below 75% and no rain (recommended temperature: 20-30°C). Avoid high humidity or bad weather that may affect the test accuracy.
Test Progress
Perform the test under suitable environmental conditions: relative humidity below 75% and no rain (recommended temperature: 20-30°C). Avoid high humidity or bad weather that may affect the test accuracy.
Measure and Record
Start the test and record the following parameters:
The voltage ratio between the windings
Deviation of the measured value from the rated ratio
The voltage ratio between the windings
Deviation of the measured value from the rated ratio
Temperature Correction
If necessary, perform temperature correction on the measured turns ratio data (especially when testing at higher or lower temperatures). Generally, the standard reference temperature for temperature correction is 20°C.
Repeat Testing (if necessary)
Test the transformer's windings of different voltage levels (high voltage, medium voltage, and low voltage) separately to ensure that the turns ratios of all windings are normal.
Evaluation Criteria (Reference)
Turns ratio error ≤ 0.5% (pass)
0.5% < Turns ratio error ≤ 1% (caution)
Turns ratio error > 1% (further inspection or corrective action required)
0.5% < Turns ratio error ≤ 1% (caution)
Turns ratio error > 1% (further inspection or corrective action required)
*These comprehensive tests ensure that each transformer meets performance standards and operates
reliably under various conditions.
Application
This customized high-voltage transformer is ideal for utility substations, industrial power distribution networks, renewable energy plants, mining operations, steel mills, and large commercial power infrastructures. It supports long-distance transmission, heavy-load operation, grid voltage regulation, and stable high-voltage distribution in demanding operational environments.
Technical Advantages
● 30+ years of manufacturing experience
● ISO and UL certified production
● Customized cable and transformer solutions
Product Packaging
Transformers Packaging (1)
Transformers Packaging (2)
Transformers Packaging (3)
Transformers Packaging (4)
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Transformers Packaging (8)
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What is a Transformer?A transformer is an electrical device used to change the voltage of alternating current (AC). It works on the principle of electromagnetic induction, converting high-voltage current into low-voltage current or low-voltage current into high-voltage current. Transformers are widely used in power transmission, distribution systems, and various electronic devices.
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What are the main uses of a transformer?The main use of a transformer is voltage conversion. Transformers are used in power transmission systems to help transfer electricity from power plants to consumers. In addition, transformers are also used in electronic devices such as chargers, televisions, power adapters, etc., to adjust the voltage to meet the requirements of different devices.
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Do you have UL listed?Yes, our transformer has UL listed. We have exported to America many pad mounted transformer,substation transformer and HV.
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