3150kva 35/0.4KV Oil Immersed Distribution Transformers

3150kva 35/0.4KV Oil Immersed Distribution Transformers

1. Technical Parameters

2. Product Description

3150kva 35/0.4KV Oil Immersed Distribution Transformers are high-capacity, low-loss medium-voltage power distribution equipment designed for 35kV grade power grid systems. As a mainstream heavy-duty oil immersed power transformer in industrial and utility power industries, this three-phase distribution transformer focuses on 35kV high voltage to 0.4kV low voltage step-down conversion, perfectly solving the large-load power distribution and voltage matching demands of large industrial bases, regional power grids and new energy power stations.

This 35kV 3150kVA oil filled transformer adopts upgraded S11-M low-loss manufacturing technology, equipped with high-quality cold-rolled oriented silicon steel sheet core and 100% pure copper winding coils. The optimized core lamination and winding layout effectively suppress magnetic flux leakage, greatly reduce no-load and load operating losses, and deliver excellent energy-saving performance compared with traditional old-fashioned transformers. Adopting fully sealed corrugated oil tank structure, the whole machine isolates external moisture, dust and corrosive gas, effectively preventing insulating oil aging and deterioration, and ensuring long-term stable insulation performance.

Configured with standard no-load off-circuit tap changer, this heavy-duty oil immersed distribution transformer allows manual voltage adjustment under power-off conditions to adapt to grid voltage deviation in different regions and stabilize output voltage within the standard range. All finished products pass strict factory tests including insulation resistance test, power frequency withstand voltage test, short-circuit resistance test and temperature rise test. Certified with ISO9001 quality system and fully compliant with international electrical safety standards, this 3150kVA medium voltage transformer features stable operation, strong overload resistance and ultra-low noise, becoming the preferred power transformation equipment for large-scale power distribution and grid upgrading projects.

3. Core Product Features

3.1 High-efficiency Energy-saving & Low Operating Loss

Adopting first-class energy-efficient silicon steel core and high-conductivity copper windings, the 3150kVA 35/0.4KV oil immersed distribution transformer achieves extremely low no-load loss and load loss indicators. The overall energy consumption is far lower than national standard requirements, which effectively reduces long-term grid operation loss and user power consumption costs. It supports 24-hour full-load continuous operation, showing outstanding energy-saving advantages in long-term stable power supply scenarios.

3.2 Stable Voltage Output & Strong Anti-fluctuation Ability

The professional Dyn11 connection group design ensures balanced three-phase voltage and current output, effectively suppresses harmonic interference and avoids three-phase unbalanced power supply faults. The ±2×2.5% no-load voltage regulation range can cope with conventional grid voltage fluctuations in different regions, calibrate terminal voltage deviation, and ensure 0.4kV low-voltage output is always within the safe and standard range. With 7% standard short-circuit impedance, the equipment has strong short-circuit impact resistance to protect rear-end electrical equipment.

3.3 Excellent Heat Dissipation & High Load Adaptability

Equipped with standard ONAN natural oil circulation heat dissipation system, insulating oil circulates freely inside the fully sealed tank to evenly take away operating heat without local overheating. The optimized oil circuit and heat dissipation structure improves heat exchange efficiency, enabling the transformer to stably bear long-term rated load and short-term overload operation. It can adapt to continuous power supply demands of high-load industrial parks and large power distribution stations.

3.4 High Safety & Strong Environmental Adaptability

With high insulation level of AC95kV and LI170kV, this 35kV large-capacity oil immersed transformer has excellent lightning impulse resistance and breakdown resistance. The fully sealed structure has good moisture-proof, dust-proof and anti-corrosion performance, adapting to indoor distribution rooms and outdoor open-air installation environments. It can operate stably in the temperature range of -25℃ to +40℃, suitable for complex and harsh industrial and outdoor power distribution scenarios.

3.5 Low Maintenance & Ultra-long Service Life

The integrated fully sealed oil tank completely avoids insulating oil oxidation and leakage, eliminating the need for frequent oil replacement and routine maintenance. The internal mechanical and electrical structure is firm and compact, with strong mechanical shock resistance and anti-aging ability. The designed service life of the whole machine exceeds 30 years, which greatly reduces later operation and maintenance costs, equipment downtime loss and replacement frequency, realizing long-term unattended stable operation.

4. Core Purpose & Application Scenarios

4.1 Core Purpose

As a key core device of 35kV medium-voltage power distribution system, 3150kva 35/0.4KV Oil Immersed Distribution Transformers mainly undertake the step-down conversion function from 35kV high-voltage grid power to 0.4kV low-voltage industrial and civil power. It is responsible for regional large-capacity power distribution, voltage stabilization and power transmission matching, solves the problems of high loss and unstable voltage in long-distance low-voltage power supply, and provides safe, stable and efficient power guarantee for various high-load power consumption terminals and grid-connected systems.

4.2 Typical Application Scenarios

Large Industrial Park Power Distribution: Widely used in large manufacturing industrial zones, chemical industrial parks, metallurgical bases and mining enterprises. The 3150kVA large capacity perfectly matches the centralized high-load power demand of multiple production workshops and large mechanical equipment, realizing stable and low-loss regional power supply.

Urban & Rural Power Grid Upgrading: Suitable for urban central power distribution stations, suburban grid reconstruction and rural large-scale power grid capacity expansion projects. It replaces outdated high-loss transformers, improves regional power supply capacity and voltage stability, and meets the growing industrial and residential electricity demand.

New Energy Power Station Supporting: Ideal for large centralized photovoltaic power stations, wind power plants and energy storage power distribution systems. It completes voltage conversion and grid matching for new energy power generation, stabilizes grid-connected voltage quality, and supports large-capacity new energy grid-connected power transmission.

Public Infrastructure Power Supply: Applied to large-scale comprehensive commercial districts, hospital clusters, university campuses and urban public service facilities. It provides continuous and stable large-capacity power guarantee for high-density power consumption areas to ensure normal operation of public infrastructure.

Key Engineering & Regional Power Guarantee: Used for national key infrastructure projects, industrial concentration zones and regional independent power supply systems. It adapts to long-term full-load operation and ensures reliable power supply for important projects and regional power systems.

5. FAQ (Frequently Asked Questions)

5.1 What are the advantages of 3150kVA 35/0.4kV oil immersed transformer compared with dry-type transformers of the same capacity?

For 35kV high-voltage and large-capacity 3150kVA power distribution scenarios, oil immersed distribution transformers have obvious comprehensive advantages. First, the oil cooling system has better heat dissipation efficiency and stronger continuous overload capacity, more suitable for long-term full-load operation of high-load power stations. Second, the fully sealed oil immersed structure has better anti-aging and anti-corrosion performance, adapting to outdoor and harsh industrial environments that dry-type transformers cannot adapt to. In addition, it has lower manufacturing cost and longer service life under the same capacity, with lower long-term operation and maintenance costs, making it more cost-effective for large-scale grid and industrial power distribution projects.

5.2 What is the difference between no-load voltage regulation and on-load voltage regulation for this 35kV 3150kVA transformer?

This standard 3150kVA oil immersed distribution transformer adopts no-load off-circuit voltage regulation, which requires power-off operation for tap adjustment. It is suitable for most conventional power distribution scenarios with stable grid voltage and infrequent voltage fluctuation, featuring simple structure, low failure rate and low cost. On-load voltage regulation transformers can adjust voltage under live operating conditions, suitable for scenarios with frequent grid voltage changes and high power supply stability requirements. For conventional industrial power distribution and urban and rural grid projects, no-load voltage regulation models can fully meet the demand with higher cost performance and more stable operation.

5.3 What daily maintenance work is required for long-term operation of 3150kVA 35/0.4KV oil immersed transformer?

This fully sealed large-capacity oil immersed transformer has low daily maintenance pressure. Daily inspection only needs to check the oil tank for oil leakage, confirm the integrity of high and low voltage bushings, monitor operating noise and real-time temperature, and ensure no sundries are stacked around the equipment to maintain smooth heat dissipation. It is recommended to test insulating oil performance and insulation resistance every 3 years, and conduct a comprehensive mechanical and electrical overhaul every 10 years. Avoid long-term overload operation and operation beyond the specified temperature and altitude range, which can effectively extend the service life and ensure stable and safe operation of the equipment for a long time.