I. Product Introduction

The SZ20-110kv series three-phase oil-immersed on-load tap-changing power transformer is a new generation of ultra-high energy efficiency distribution equipment developed to meet national carbon peaking and carbon neutrality goals as well as power grid energy-saving upgrades. It strictly complies with GB 1094 power transformer standards and GB 20052-2020 mandatory energy efficiency standards.

Adopting high-permeability low-loss oriented silicon steel sheets and oxygen-free full-copper windings, combined with advanced vacuum oil filling, integral compression and fully sealed manufacturing technology, as well as high-precision on-load tap-changer, it can realize continuous, stable and uninterrupted voltage regulation under load conditions.

With the advantages of ultra-low loss, ultra-low noise, strong short-circuit resistance, high reliability and long service life, it is the preferred high-end energy-saving transformer for urban grid renovation, industrial park power supply, new energy access, large public buildings and rail transit.

II. Technical Parameters (Take SZ20-110kv as an example)（customizable）

• Model: SZ20-110kV

• Voltage combination: 35±3×2.5%kV / 10.5kV

• Voltage regulation: On-load tap-changing

• Connection group: Dyn11

• Rated frequency: 50Hz

• Cooling mode: ONAN / ONAF

• Insulation level: LI95AC35kV

• Energy efficiency class: Class 1 (GB 20052-2020)

• Operating temperature: -40℃ ~ +40℃

• Altitude: ≤1000m

• Protection class: IP00

• Executive standards: GB 1094, GB 20052-2020

III. Main Features

1. Level 1 energy efficiency, ultra-high energy saving

   Adopts ultra-low loss core and optimized electromagnetic design. No-load and load losses are much lower than SZ18 and traditional models, reaching Class 1 energy efficiency of GB 20052-2020, greatly reducing long-term operating costs.

2. On-load voltage regulation, uninterrupted power supply

   Equipped with high-performance on-load tap-changer, enabling automatic voltage regulation without power outage under load fluctuation, ensuring stable output voltage for applications requiring high power continuity.

3. Full-copper windings, strong short-circuit withstand capability

   Adopts full-copper windings, high-strength insulation structure and integral fastening technology, featuring high mechanical strength, low partial discharge, strong resistance to short-circuit impact, stable operation, low failure rate and long service life.

4. Low noise and vibration, environment-friendly

   Optimized core and oil tank with shock absorption and noise reduction design, low operation noise and vibration, ideal for residential areas, indoor substations, hospitals, schools and other noise-sensitive places.

5. Compact structure, easy operation and maintenance

   Fully sealed oil-immersed structure prevents insulation oil aging, moisture and leakage. Complete pressure, temperature, oil level monitoring and protection devices are equipped, making installation and maintenance convenient.

6. Wide adaptability, high reliability

   Can operate stably under complex conditions such as high/low temperature, high humidity and dusty environments, suitable for long-term continuous operation in power grids, industries and new energy projects.

IV. Application Scenarios

• Power grid system: Urban and industrial park substations, regional distribution stations, energy-saving replacement of old transformers, grid capacity expansion and quality improvement.

• Industrial power supply: Metallurgy, petrochemical, coal, mining, manufacturing and other high-power, high-stability load sites.

• New energy: PV power stations, wind power grid connection, energy storage stations, large charging station supporting transformers.

• Public buildings: Data centers, airports, high-speed rail stations, hospitals, stadiums, shopping malls, office buildings and other important load places.

• Infrastructure & transportation: Rail transit, highways, ports, terminals and other scenarios requiring high-reliability and energy-saving power supply.