110kV Oil-Immersed Main Transformer

110kV three-phase two-winding / three-winding on-load tap-changing main transformers are core equipment for 110kV regional central substations, widely used in Zambia provincial power grid construction, large-scale mining concentrated power supply bases, mega photovoltaic power station booster stations, industrial park hub substations and urban power grid upgrading projects.

Products strictly comply with IEC 60076 international standard and national GB 1094 series power transformer standards. Adopt high-performance mineral insulating oil for insulation and heat dissipation, equipped with on-load voltage regulation switch to adapt to large-amplitude grid voltage fluctuation in Zambia remote areas. Our factory supports full customized design of main transformers with all-copper winding, and two unified unit price quotation standards are available for overseas project bidding: 0.0901 USD / W (Standard energy efficiency model) & 0.102 USD / W (Ultra-low loss energy-saving model). The high-efficiency version is about 13.21% higher in unit price, suitable for long-term grid grid-connected operation to reduce comprehensive power loss cost.

1. Ultra-High Grade Reinforced Insulation System for 110kV Voltage Level

High voltage winding adopts multi-layer interleaved composite insulating paper + electrostatic shielding structure, lightning impulse withstand voltage up to 480kV, with extremely large insulation safety margin. Effectively resist thunderstorm overvoltage, line switching surge and long-distance line voltage drop of Zambia 110kV overhead transmission network, prevent main insulation breakdown and inter-turn short-circuit accidents. Core winding all adopt 99.99% oxygen-free copper transposed wire, strong anti-short-circuit mechanical impact capability, can withstand short-circuit current impact of power grid fault without coil deformation.

2. Low-Loss High-Grade Silicon Steel Core & Dual Price Scheme

Iron core uses high-permeability laser-dot oriented silicon steel sheet, 45° full miter lap cutting process, no binding hole structure, greatly reduce no-load loss, no-load noise and no-load excitation current.

• 0.0901 USD/W: Standard energy efficiency main transformer, lower one-time project procurement cost, applicable to temporary power supply and short-cycle infrastructure substation projects;

• 0.102 USD/W: National first-class ultra-low loss energy-saving main transformer, no-load & load loss indicators are significantly optimized, annual power consumption loss is greatly reduced, very suitable for provincial grid hub substations and large photovoltaic booster stations with 24-hour uninterrupted operation.

3. On-Load Tap Changer & Stable Voltage Output

Equipped with built-in on-load tap voltage regulating switch, voltage adjustment range commonly ±8×1.25% (customizable ±4×2.5% according to local grid requirements). It can complete voltage regulation under load without power cut, solve the problem of large voltage fluctuation at the end of Zambia long-distance transmission lines, and ensure the stability of 35kV / 10kV outgoing side voltage.

4. Multi-Level Heat Dissipation Mode & Strong Overload Capacity

Support three cooling modes optional:

1. ONAN Natural Circulation Natural Air Cooling

2. ONAF Natural Circulation Forced Air Cooling

3. OFAF Forced Circulation Forced Air Cooling

Equipped with multi-group top-mounted radiators and dedicated cooling fans; can achieve 130% long-term overload operation under forced air cooling condition, and 150% emergency short-time overload to cope with peak power consumption of mines and industrial loads.

5. Complete Protection System & Outdoor Anti-Corrosion Structure

Standard complete protection accessories: main oil conservator, capsule oil storage tank, pressure relief explosion-proof valve, gas relay (buchholz relay), winding & oil temperature online monitoring system, moisture absorber, oil sampling valve, grounding device, lifting jack and transportation fixing support. Tank body adopts thickened steel plate, sandblasting derusting + epoxy anti-rust primer + outdoor weather-resistant heavy-duty anti-corrosion finish paint, anti-high temperature, anti-humidity and anti-light salt fog, adapt to Zambia tropical climate for long-term outdoor unattended operation. All sealing parts use imported high-temperature resistant fluorine rubber to eliminate oil leakage risk.

6. Shipping Plan to Zambia (Sea & Air)

Sea Transportation (Mainstream Solution for Main Transformer)

Fill qualified transformer insulating oil completely before delivery, adopt ISPM15 standard fumigation wooden box or steel frame reinforced packaging, suitable for large-capacity main transformer bulk order, low unit logistics cost, longest transportation cycle.

Air Transportation (Only for Small Capacity Main Transformer)

Must implement strict pretreatment before air shipment:

1. Thoroughly drain all insulating oil from main tank, radiator, oil conservator and pipeline;

2. Closed hot air circulation drying, remove all residual oil film inside coil and tank;

3. Seal all flanges and nozzles, inject dry nitrogen with dew point ≤-40℃ and maintain micro positive pressure;

4. Apply magnetic field detection report and non-dangerous goods transportation condition appraisal certificate. Extra fees for oil drainage, drying, nitrogen sealing and inspection documents will be generated; oversized main transformers are generally not recommended for air freight due to aircraft cabin size limit.

7. Full Customization & Export After-Sales Guarantee

Customizable items: Capacity, winding form (two-winding / three-winding), high-low voltage combination (110/35kV, 110/10.5kV, 110/35/10.5kV), impedance voltage, tap range, cooling mode, protection configuration, remote communication protocol (MODBUS-RTU / IEC61850). Full set of Zambia customs clearance documents: factory official type test report, ISO9001, CE, IEC certification, fumigation certificate, commercial invoice, packing list, magnetic inspection document (air freight only). 5-year global whole machine warranty, lifelong cost price supply of spare parts; provide full English operation, maintenance and installation manuals. We can dispatch senior electrical engineers to Zambia for on-site installation guidance, commissioning and personnel operation training.

1. Two-Winding Main Transformer (110±8×1.25% / 10.5kV)

2. Three-Winding Main Transformer (110±8×1.25% / 38.5 / 10.5kV)

Q1: Can 110kV main transformer be transported by air to Zambia?

A: Only small-capacity models below 10MVA have the possibility of air shipment, and oil draining, drying, nitrogen sealing, magnetic inspection and non-dangerous identification are mandatory. Large-capacity main transformers exceed aircraft size and weight limit, only sea freight is available.

Q2: What is the difference between two quotation units 0.0901 USD/W and 0.102 USD/W?

A: 0.0901 USD/W is standard loss main transformer with lower initial bid cost; 0.102 USD/W is low-loss energy-saving type, the loss parameter is reduced obviously, which can save a large amount of grid loss electricity fee in long-term operation, the unit price increases by about 13.21%, both adopt full pure copper winding.

Q3: Can parameters be customized according to Zambia national grid standards?

A: Fully support customization, including voltage combination, tap mode, impedance value, protection logic, communication signal, anti-lightning reinforcement structure, all can be adjusted according to local power grid technical specifications.

Q4: What after-sales technical support can be provided?

A: 5-year whole machine warranty, lifetime preferential supply of spare parts. Provide complete English version drawing, test report and operation manual. Engineers can be sent to Zambia for on-site installation, commissioning and operation training upon customer's request.