30MVA Oil Type Transformer with On-load Tap-changer for High-energy Demand

Pearl Electric's Transformers with On Load Tap Changing (OLTC) are engineered to dynamically regulate voltage output without interrupting power supply, ensuring seamless operation in environments with fluctuating load demands. 

This transformer with On Load Tap Changing (OLTC) refers to a type of transformer that is equipped with a tap changer mechanism designed to adjust the turns ratio and regulate the output voltage while the transformer is in operation. Unlike traditional off-circuit tap changers, OLTC allows for tap changes without interrupting the power supply.

Designed for precision and reliability, these transformers are ideal for power distribution networks, industrial complexes, renewable energy systems, and mission-critical facilities. They provide precise voltage control and ensure reliable and stable power supply, enhancing the performance and efficiency of high-energy demand electrical systems.

Product Parameters

Features of 30MVA Oil Type Transformer with On-load Tap-changer for High-energy Demand

Voltage regulation : The OLTC feature enables real-time adjustments to the transformer's turns ratio, allowing precise control over the output voltage to maintain desired levels even during fluctuating load conditions.

Continuous operation:  Tap changes can be made while the transformer is energized, eliminating the need for power interruptions or shutdowns during voltage adjustments.

Flexibility: With multiple tap positions available, OLTC transformers offer flexibility in accommodating varying input voltages and load requirements, ensuring optimal performance and efficient power distribution.

Power quality improvement: By regulating the output voltage, OLTC transformers help improve power quality by minimizing voltage fluctuations and maintaining a stable supply to connected loads.

Load optimization: OLTC allows for adjustments to match the changing load demands, optimizing energy efficiency and reducing energy wastage.

Advatages of 30MVA Oil Type Transformer with On-load Tap-changer for High-energy Demand

Enhanced Cooling Efficiency: Mineral oil efficiently dissipates heat generated during high-load operations, reducing thermal stress on windings and insulation. This prolongs the transformer’s lifespan and maintains performance under continuous heavy loads.

High Load Capacity and Reliability: Suitable for industrial plants, utility substations, or large commercial complexes, this capacity ensures robust power handling without overload risks. OLTC optimizes efficiency across variable loads, aligning with fluctuating energy demands.

Operational Continuity: OLTC eliminates the need to de-energize the transformer during adjustments, crucial for industries requiring uninterrupted power, such as manufacturing or data centers.

Cost-effective: While initial costs may be higher, the combination of oil cooling (reducing wear) and OLTC (optimizing efficiency) lowers energy losses and operational expenses over time. Scalability via OLTC also defers costly upgrades as demand grows.

Durability and Longevity: Oil-type transformers are typically designed for outdoor use, withstanding harsh environments. Proper maintenance (e.g., oil testing) ensures decades of service, especially under thermal management provided by oil.

Applications of 30MVA Oil Type Transformer with On-load Tap-changer for High-energy Demand

This combination of robust design, adaptive voltage control, and efficient cooling makes the 30MVA oil-type transformer with OLTC a cornerstone for high-energy demand scenarios.

Industrial Complexes: This transformer is ideal for use in regional and national power grids where reliable energy distribution is critical. Steel mills, chemical plants, and manufacturing facilities with heavy machinery that cause variable loads，and efficient cooling for sustained high-energy demands in outdoor industrial settings.

Renewable Energy Integration: Compensates for voltage fluctuations caused by intermittent renewable output，this kind of transformer connecting wind/solar farms to the grid, where generation varies with weather.

Mining Operations: 30MVA supports energy-intensive extraction and processing activities，this transformer is suitable for remote mines with high-power equipment (e.g., crushers, conveyors) and long transmission lines，the advantage of OLTC mitigates voltage drop over long distances and handles load swings from heavy machinery.

Data Centers: Ensures voltage regulation despite rapid load changes from server activation/deactivation，this transfomer is suitable for facilities requiring stable power for servers and cooling systems.

Electric Railway Networks：This transformer make outdoor installation along rail corridors aligns with safety protocols，can adjusts voltage to maintain consistency during sudden load spikes (e.g., multiple trains starting)，that ideal for power supply for trains/subways with frequent acceleration/deceleration.

Power Generation Plants：auxiliary transformers in hydroelectric/thermal plants for internal power distribution facilitate efficient grid interconnection at optimal transmission voltages.

Transformer Production Technology

• TRANSFORMER WINDINGS

For the low and high voltage coils, either copper or aluminum can be used as conductor material according to the standards or customer requirements. Winding are separated as LV Windings and HV Windings.

Conductor types according to voltage level and load losses:

-On LV coil: Foil (sheet) or paper insulated rectangular sectioned

-On HV coil: Enamel insulated round or paper insulated rectangular sectioned conductors are used.

The windings are made of resin coated DDP and special Kraft paper resistant to high shock and electrical withstand. The structure of this specially formed layer insulation increases the impulse voltage properties. The layer insulation also helps in achieving another important goal: to produce a rigid coil without space.

• VENTILATION

Transformers are naturally cooled with ONAN ventilation. According to customer requirements, transformers with ONAF ventilation can be also manufactured.

• TRANSFORMER CORE

The core transformers are made of cold rolled grain oriented silicon steel (CRGO).

The steels are choosen according to no-load loss value M5, MOH, HI-BI quality class and 0,30-0,23 mm thickness range.

Cores are cut fast and without burr by modern transformer lamination cut machine. The cores are aligned according to the project data with step-lap method to reduce losses and noise.

• ACTIVE PARTS

Active part is formed by the placement of the coils to core legs and alignment of the upper core. Yoke clamps and wedges are placed to compress the coils. Cover, terminal and tap changer installations are done to make it ready for first pre-tests. The alignment of the insulations on the cover, accessories and other equipments are done according to the customer requirements

• TANK AND PAINT

Tanks are in 2 types: with radiator and corrugated walls. Tank base and top covers are made of mild steel. Corrugated walls of front and side surfaces o the tank also forms the cooling surfaces.

Front and side surfaces are made of steel sheet in tank with radiator,

Tanks are sealed with welding. Tanks are cleaned with special chemicals and dry before painting. Corrosion resistant and hardly adhesive undercoat paint is applied as two layers. After undercoating the tanks are subjected to drying process. After drying process, topcoat paint is applied on the undercoating according to the customer's dye thickness requests. The tanks wait in the drying Owens. RAL 7033 color code is used as to coating paint (or with different colors as per customer requests). Inner surface of the tank is coated with special varnish.

• DRYING AND FILLING

Low Frequency Technology for Drying and Filling Oil immersed type distribution transformer, the insulation materials have to be dried before oil filling. This drying process affects the quality of the transformer directly. Pearl Electric chose Vacuum Drying Technology for drying and filling under vacuum environment. Humidity is reduced to minimum in the oil and in the active part of the tank by this process.

FAQs of  30MVA Oil Type Transformer with On-load Tap-changer for High-energy Demand

1. What is the purpose of an On-Load Tap-Changer (OLTC) in a 30MVA transformer? 

The OLTC allows voltage adjustment without interrupting power flow, ensuring stable voltage output even during load fluctuations. This is critical for high-energy demand applications like industrial plants or grid substations, where sudden load changes (e.g., motor startups, renewable energy variability) require real-time voltage regulation.

2. Why choose a 30MVA rating for high-energy applications?

A 30MVA transformer balances power capacity and cost-effectiveness for medium-to-large-scale operations. It is ideal for: industrial complexes (steel mills, chemical plants)；urban substations serving 10,000+ households；renewable energy farms (solar/wind) requiring grid synchronization.

3. How does the OLTC handle voltage fluctuations in renewable energy integration?

Renewables like solar/wind farms generate variable power due to weather conditions. The OLTC adjusts the transformer’s turns ratio in real time to: compensate for voltage drops during low generation；prevent overvoltage during peak generation；ensure seamless grid compliance (e.g., IEEE 1547 standards).

4. How does this transformer support grid stability during peak demand?

OLTC adjusts taps to compensate for grid voltage drops during peak loads, and maintains power factor, reducing strain on transmission lines.

5. Can 30MVA oil type transformer with on-load tap-changer be customized?

Yes, transformers can be customized to specific requirements, including winding material (copper or aluminum) and insulation options (mineral oil or FR3 oil).