High-Efficiency and Energy-Saving 110 kV Oil-Immersed Transformers for Long-Distance Transmission Lines

As power transmission distances continue to expand, long-distance transmission lines place increasingly stringent demands on core power equipment. Among them, 110 kV high-efficiency and energy-saving oil-immersed transformers play a critical role in ensuring stable, economical, and reliable power delivery. Driven by advances in materials, insulation systems, and intelligent monitoring technologies, these transformers now offer significantly improved efficiency and operational reliability for modern transmission networks.

Performance Requirements for Long-Distance Transmission Transformers

Compared with conventional distribution networks, long-distance transmission systems operate under more complex conditions. Extended transmission distances lead to cumulative energy losses along the line, while large and frequent load fluctuations require transformers to operate continuously under high load. In addition, voltage stability and system reliability are more critical, as maintenance intervals are longer and outage-related costs are significantly higher. As a result, 110 kV transformers used in long-distance transmission must deliver low losses, high reliability, long service life, and stable performance.

Technical Features of 110 kV High-Efficiency Energy-Saving Oil-Immersed Transformers

Low-Loss Core Design

Modern 110 kV energy-saving oil-immersed transformers adopt high-performance grain-oriented silicon steel or amorphous alloy core materials. Compared with conventional designs, no-load losses can be reduced by approximately 30% to 50%. Optimized magnetic circuit design ensures efficient operation even under voltage fluctuations commonly encountered in long-distance transmission lines.

Advanced Insulation and Cooling System

To meet the demands of continuous and high-load operation, these transformers use high-temperature-resistant insulating paper combined with advanced insulating oil, significantly improving thermal endurance. Enhanced cooling systems, including intelligent air cooling or forced oil circulation, automatically adapt to load variations. Fully sealed tank structures effectively prevent oil aging and moisture ingress, extending maintenance cycles and making them ideal for remote transmission corridors.

Integrated Intelligent Monitoring

Built-in online monitoring systems enable real-time data collection of critical operating parameters such as oil temperature, load current, and partial discharge levels. Through Internet of Things (IoT) connectivity, operators can remotely assess transformer health and perform predictive maintenance, reducing the risk of unexpected failures in long-distance transmission networks.

On-Load Tap Changer for Voltage Regulation

To address voltage drop and fluctuation over long transmission distances, 110 kV oil-immersed transformers can be equipped with on-load tap changers. This allows voltage adjustment without interrupting power supply, improves voltage quality at the receiving end, and enhances grid dispatch flexibility. This function is especially important for inter-regional transmission systems with variable load conditions.

Main Application Scenarios

High-efficiency 110 kV oil-immersed transformers are widely applied in regional grid interconnection projects and inter-regional power transmission lines. They are commonly used in step-up substations for thermal, hydropower, wind, and photovoltaic power plants, as well as hub substations in urban main grids supplying electricity to suburban and remote areas. In addition, they are suitable for captive power plants and dedicated transmission lines serving large industrial and mining enterprises.

Selection and Configuration Recommendations

Key Technical Parameters

Transformer capacity should be selected based on actual load characteristics and anticipated future expansion. Short-circuit impedance must be matched to transmission line parameters to ensure system stability. For voltage regulation, on-load tap changer configurations with a regulation range of not less than ±8 × 1.25% are recommended. For outdoor installations, a protection level of at least IP55 is advised to ensure adequate dustproof and waterproof performance.

Recommended Intelligent Configurations

To further enhance reliability and operational efficiency, intelligent configurations such as online partial discharge monitoring, oil chromatographic analysis sensors, intelligent temperature control systems, and remote communication interfaces supporting IEC 61850 protocols are strongly recommended.

With the continuous expansion of power grids and the accelerating transformation of energy structures, high-efficiency and energy-saving 110 kV oil-immersed transformers are becoming indispensable in long-distance power transmission. Their advantages in low losses, high reliability, mature technology, and intelligent operation make them an ideal solution for regional grids and inter-regional transmission projects. Through proper selection, configuration, and standardized operation and maintenance, these transformers provide strong technical support for the safe, economical, and sustainable development of modern power systems.