Project Overview

The Ningxia–Hunan ±800kV Ultra High Voltage Direct Current (UHVDC) Transmission Line Project is a major power infrastructure undertaking aimed at improving long-distance electricity transmission from Ningxia to Hunan Province. The project contributes to China’s west-to-east electricity transmission initiative, supporting the delivery of power to central and eastern regions while facilitating the use of renewable energy.

Spanning approximately 1,500 kilometers, the transmission line represents a large-scale deployment of UHVDC technology. Key components include:

• Converter stations at sending and receiving ends for DC-AC power conversion

• High-capacity conductors designed to reduce transmission losses over extended distances

• Transmission towers adapted for diverse terrains, including desert, mountainous, and urban areas

The project enhances interregional grid connectivity and contributes to energy diversification by integrating power generated from cleaner sources.

Construction Plan & Execution

1. Route Survey & Planning

Extensive topographic, meteorological, and geological assessments were conducted to determine an optimal transmission route. The line traverses a range of environments, including:

• Desert areas in Ningxia, where structures were designed with sand-resistant coatings

• Mountainous regions requiring rock-anchor foundations and helicopter-assisted installation

• Forested and urban zones in Hunan, where environmental and social impacts were considered during planning

Geographic Information Systems (GIS) and electromagnetic compatibility (EMC) studies were applied to manage transmission efficiency and minimize interference with nearby infrastructure.

2. Tower Foundations & Structural Engineering

Multiple foundation types were adopted to suit varying soil and terrain conditions:

• Rock-anchor foundations in mountainous zones for structural reinforcement

• Deep pile foundations in loose soils to prevent shifting

• Raft foundations in populated or restricted areas to reduce land impact

Transmission towers featured:

• Steel lattice structures designed for high-voltage loads and weather variability

• Surface treatments for resistance against corrosion, wind, and temperature extremes

• Aerodynamic profiles to reduce wind load and mechanical stress

Construction methods included both aerial tower assembly and ground-based techniques depending on accessibility.

3. Conductor Installation & Stringing

To support long-distance transmission, the conductor installation process involved:

• High-performance conductors engineered for minimal energy loss

• Precision stringing techniques to maintain alignment and tension

• Insulation systems adapted for high altitudes and humidity

Polymer insulators were applied for their electrical and mechanical characteristics under diverse environmental conditions.

4. Converter Stations & Grid Integration

Converter stations in Ningxia and Hunan enable AC-DC and DC-AC conversion, with features such as:

• Thyristor valve systems for controllable voltage regulation

• Cooling equipment suited to a wide range of operating temperatures

• Harmonic filtering and compensation devices for smoother integration into the AC grid

This arrangement supports dynamic power adjustment and contributes to transmission efficiency across the corridor.

Design & Technical Services

1. Power System Optimization & Electrical Engineering

Design services covered:

• Load flow and fault current analysis to guide system configuration

• EMC design to limit interference with communication and protection systems

• Insulation coordination strategies adapted to environmental conditions

2. Smart Monitoring & Control Systems

The project incorporates monitoring and control technologies, including:

• Fault detection systems for proactive maintenance

• SCADA-based remote management platforms

• Automated protection systems to support grid responsiveness

3. Environmental & Sustainability Measures

Environmental considerations were integrated throughout the project, including:

• Route alignment adjustments to avoid sensitive areas

• Land restoration and reforestation efforts where applicable

• Tower-mounted bird diverters to reduce impacts on local wildlife

After-Sales Service & Maintenance

1. Scheduled Maintenance & Inspection

Ongoing support includes routine inspections and diagnostics for:

• Converter station components such as transformers and filters

• Tower integrity in various climate zones

• Conductor and insulator maintenance for system longevity

2. Emergency Response & Fault Repair

A support team is available to address potential issues, including:

• Voltage irregularities or power disruptions

• Weather-related structural damage

• Equipment replacement to minimize operational interruptions

3. System Upgrades & Future Expansion

Services are available for long-term adaptability, including:

• Conductor upgrades to meet evolving demand

• Next-generation converter technology deployment

• Predictive maintenance applications using data analytics

4. Training & Technical Support

We offer:

• On-site and remote training programs for grid operators

• Technical workshops on UHVDC systems

• Round-the-clock support channels for system optimization and troubleshooting

Conclusion

The Ningxia–Hunan ±800kV UHVDC Transmission Line Project represents a significant effort to improve long-distance power delivery and support renewable energy integration within China’s national grid. Through adaptable engineering, digital monitoring systems, and continued technical support, the project contributes to the modernization of interregional energy infrastructure.

For more information about UHVDC transmission solutions, system design, or maintenance services, please contact us.