100kVA–20MVA Solar Step-Up Transformer for PV Power Plants
The 100kVA–20MVA Solar Step-Up Transformer is engineered specifically for modern solar power plants, providing efficient voltage elevation from inverter output levels to medium- or high-voltage grid requirements. Designed for continuous operation under fluctuating solar loads, this transformer ensures stable power transmission, low energy losses, and high operational reliability. Featuring a robust oil-immersed insulation system, the transformer delivers excellent thermal performance and long service life even in harsh outdoor environments. High-quality copper or aluminum windings, optimized magnetic core design, and advanced cooling configurations contribute to superior efficiency and reduced lifecycle costs. The transformer complies with IEC and IEEE standards, making it suitable for utility-scale photovoltaic projects, distributed generation systems, and renewable energy substations. With flexible capacity coverage from 100kVA to 20MVA, it adapts seamlessly to small, medium, and large solar installations.
- Primary Voltage Ratings 11kV - 33kV or others
- Secondary Voltage Ratings 0.315kV, 0.38kV, 0.48kV, 0.6kV, 0.69kV, 0.8kV or customized
- H.V. Tap Range ± 2×2.5% HV taps or others
- Type Solar Step-up Transformer
- BIL 30/200kV, 30/170kV, 30/150, 30/95 or others
- Standards IEEE, ANSI, NEMA, IEC, GB
- Application ground-mounted solar power plants, industrial PV systems
- Power Rating 100kVA–20MVA
- Certificate UL ,CESI
- Cooling Method ONAN, KNAN
- Opeartion Step-up
Technical Specifications
Customization Optional
Packing and Shipping
Manufacturer Test
Routine Testing
Application
Technical Specifications
100kVA–20MVA Solar Step-Up Transformer for PV Power Plants
Technical Specifications
Accessories
| Rated Power | 100kVA–20MVA | |
| Rating Primary Voltage | 11kV - 33kV or others | |
| Secondary Voltage | Customized | |
| Frequency | 50/60Hz | |
| Vector Group | Dyn11,Ynd11,Dyn11yn11,YNd11d11 | |
| Winding Material | Aluminum/Copper | |
| Zero-Sequence Impedance | Customized | |
| Altitude | ≤1,000m or Customized | |
| Color | ANSI 70 Light gray/Munsell 7GY3.29/1.5 or customized etc | |
| Tank material | Mild Steel, 304 Stainless Steel | |
| HV Bushing |
| LV Bushing |
| Tap changer |
| Oil level gauge |
| Oil temperature indicator |
| Pressure relief device |
| CT |
| Lifting hook for complete transformer |
| Name plate |
| Radiators |
| Oil upper filtering valve |
| Oil drain valve with 3/8" sampler |
| Terminal box |
Customization Optional
100kVA–20MVA Solar Step-Up Transformer for PV Power Plants
The 100kVA–20MVA Solar Step-Up Transformer offers extensive electrical customization to meet diverse photovoltaic project requirements. Primary and secondary voltage ratings can be precisely configured to match inverter output levels and grid connection standards, including common ranges such as 400V, 690V, 800V, 1kV, 6.6kV, 10kV, 11kV, 33kV, or higher. Vector group selection is optimized for solar inverter compatibility, ensuring minimal harmonic interaction and stable synchronization with the utility grid. Customers may choose copper or aluminum windings based on efficiency targets, cost considerations, and thermal performance expectations. Tap changer options include off-circuit tap changers or on-load tap changers (OLTC) for voltage regulation under variable solar generation conditions.
Mechanical and environmental customization further enhances adaptability to site conditions. The transformer tank can be designed for outdoor installation with corrosion-resistant coatings suitable for desert, coastal, or high-humidity environments. Cooling methods such as ONAN or ONAF are selectable according to capacity and ambient temperature. Noise level optimization, fire safety features, intelligent monitoring systems, and digital temperature indicators can be integrated upon request. Accessories including surge arresters, cable boxes, and protection relays are configurable to align with EPC specifications. This flexible customization approach ensures seamless integration into any solar power plant design.
Packing and Shipping
100kVA–20MVA Solar Step-Up Transformer for PV Power Plants
The packing and shipping process for the Solar Step-Up Transformer is designed to safeguard structural integrity and electrical performance throughout transportation. Prior to packing, each transformer undergoes a final inspection to ensure all components are securely assembled and free from surface defects. External fittings, terminals, and accessories are carefully protected using reinforced covers and cushioning materials to prevent mechanical damage during handling.
Depending on project logistics and destination, the transformer may be shipped oil-filled, nitrogen-filled, or vacuum-sealed. For long-distance or overseas transport, moisture-proof wrapping and anti-corrosion treatments are applied to protect insulation systems and metallic surfaces. Bushings, radiators, and auxiliary equipment may be detached and packed separately in dedicated crates to minimize transit risk.
The transformer body is mounted on heavy-duty steel or treated wooden skids engineered to support the unit’s weight and maintain stability during lifting and transport. Shock-absorbing materials and internal bracing reduce vibration stress during road, rail, or sea transportation. All wooden packaging complies with international phytosanitary regulations such as ISPM 15.
Clear labeling, lifting instructions, center-of-gravity markings, and safety warnings are applied to each package. Complete shipping documentation—including packing list, test reports, manuals, and certificates—is provided to ensure smooth customs clearance and on-site installation. This systematic approach guarantees safe delivery and rapid commissioning upon arrival.
Depending on project logistics and destination, the transformer may be shipped oil-filled, nitrogen-filled, or vacuum-sealed. For long-distance or overseas transport, moisture-proof wrapping and anti-corrosion treatments are applied to protect insulation systems and metallic surfaces. Bushings, radiators, and auxiliary equipment may be detached and packed separately in dedicated crates to minimize transit risk.
The transformer body is mounted on heavy-duty steel or treated wooden skids engineered to support the unit’s weight and maintain stability during lifting and transport. Shock-absorbing materials and internal bracing reduce vibration stress during road, rail, or sea transportation. All wooden packaging complies with international phytosanitary regulations such as ISPM 15.
Clear labeling, lifting instructions, center-of-gravity markings, and safety warnings are applied to each package. Complete shipping documentation—including packing list, test reports, manuals, and certificates—is provided to ensure smooth customs clearance and on-site installation. This systematic approach guarantees safe delivery and rapid commissioning upon arrival.
32
32 years of industry experience
Manufacturer Test
100kVA–20MVA Solar Step-Up Transformer for PV Power Plants
Progress Test
Progress testing for the Solar Step-Up Transformer is conducted throughout the manufacturing process to ensure consistent quality and adherence to design specifications. Incoming raw materials such as electrical steel, winding conductors, insulation paper, and transformer oil are inspected and tested prior to production. Core assembly inspections verify lamination alignment, stacking pressure, and dimensional accuracy. During winding and insulation processes, in-process inspections confirm conductor tension, insulation thickness, and winding geometry. Coil assemblies undergo drying and vacuum treatment to remove residual moisture and enhance dielectric strength. Intermediate electrical checks, including winding resistance and insulation resistance tests, are performed before final assembly.
Tank fabrication and welding are inspected for structural integrity, followed by pressure and leakage tests. Prior to oil filling, internal cleanliness is verified to prevent contamination. All results are recorded in progress inspection reports, ensuring full traceability and early identification of potential deviations.
Design Tests
All transformer will be test after finished the production, test items as below:
♦ Insulation Power Factor
♦ Winding Resistance
♦ Impulse Tests
♦ On load Loss Test
♦ No Load Loss Test
♦ Leak Test
♦ DC Insulation Resistance Test
♦ Transformer Turns Ratio/TTR (All Tap Voltages)
♦ Impedance Voltage & Load Loss (Rated Voltage)
♦ Excitation & No-Load Loss (Rated Voltage)
♦ Applied Voltage
♦ Induced Voltage
♦ Lightning Impulse
♦ Insulation Resistance (Rated Voltage)
♦ Temperature Rise
Transformer Factory Acceptance Test
The Factory Acceptance Test confirms that the transformer meets all electrical, mechanical, and performance requirements. Routine tests include winding resistance, voltage ratio, polarity, and vector group verification. No-load and load loss tests confirm efficiency targets.
Dielectric tests such as applied voltage and induced voltage withstand tests validate insulation performance. Oil samples are tested for dielectric strength and moisture content. Functional testing of monitoring devices and accessories completes the FAT process, with results documented for customer approval.
Mechanical inspections ensure proper assembly, sealing, and accessory installation. Cooling system performance and alarm functions are tested. Upon completion, a comprehensive FAT report is issued prior to shipment release.
Routine Test - On load Loss Test
Purpose of Testing
The purpose of On-load Loss Test is to measure the active power loss of the transformer under rated voltage and rated load, evaluate its energy efficiency level and design compliance, and provide a basis for energy consumption calculation and performance optimization during operation.
Testing Equipment
Power transformer test system (e.g. OMICRON, ISA, Tettex, Vanguard, etc.)
Voltage source and current source (usually rated voltage, or adjusted according to the test standard, such as 10 KV, 20 KV, 35 KV, etc.)
Temperature and humidity meter (used to record ambient temperature and humidity for correction of test data)
Voltage source and current source (usually rated voltage, or adjusted according to the test standard, such as 10 KV, 20 KV, 35 KV, etc.)
Temperature and humidity meter (used to record ambient temperature and humidity for correction of test data)
Pre-Test Preparation
Disconnect the transformer high voltage, low voltage and neutral power supply to ensure that the equipment is properly grounded and safely discharged.
The test environment should be dry and rainless, with a relative humidity of less than 75% and a recommended temperature range of 20–30°C.
The test environment should be dry and rainless, with a relative humidity of less than 75% and a recommended temperature range of 20–30°C.
Test Progress
Connect the Test Instrument:
Connect the test equipment to the appropriate terminals of the device under test and ensure that all wiring is correct and the device is well grounded.
Apply Test Voltage:
Apply the specified test voltage at the rated frequency and adjust the low voltage side to maintain the rated current (or specified current).
Connect the test equipment to the appropriate terminals of the device under test and ensure that all wiring is correct and the device is well grounded.
Apply Test Voltage:
Apply the specified test voltage at the rated frequency and adjust the low voltage side to maintain the rated current (or specified current).
Measure and Record
Start the test and record the following parameters:
On-Load Loss Power
Input Power and Output Power
Current
Voltage
Temperature (temperature rise or winding temperature)
Ambient temperature and humidity during the test
On-Load Loss Power
Input Power and Output Power
Current
Voltage
Temperature (temperature rise or winding temperature)
Ambient temperature and humidity during the test
Temperature Correction
The measured loss data is corrected based on a reference temperature (usually 20°C) to ensure the accuracy of the results.
Repeat Testing (if necessary)
Test different tap positions (Tap Changer) and record and compare the load loss data of each tap point.
Evaluation Criteria (Reference)
Evaluate the test results based on the equipment type and manufacturer requirements. If the load losses are low and the efficiency is high, it is considered "normal".
Test standard
IEEE C57.12.01 & IEEE C57.12.91 (Dry-Type)
*These comprehensive tests ensure that each transformer meets performance standards and operates
reliably under various conditions.
Application
Ideal for utility-scale solar farms, distributed PV plants, and renewable energy substations, this solar step-up transformer efficiently boosts inverter output voltage for grid connection, ensuring stable and reliable power transmission.
Technical Advantages
● 30+ years of manufacturing experience
● ISO and UL certified production
● Customized cable and transformer solutions
Product Packaging
Transformers Packaging (1)
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Transformers Packaging (3)
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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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