Baihetan–Jiangsu

Overview

The Baihetan-Jiangsu HVDC project is a major power transmission system in China, designed to transmit clean hydroelectric power from the Baihetan Hydropower Station in Sichuan province to Jiangsu province in eastern China. This ultra-high-voltage direct current (UHVDC) transmission line stretches approximately 2,080 kilometers, passing through five provinces.

Technical Specifications

The project utilizes an 800 kV UHVDC transmission system with a rated transmission capacity of 8 million kilowatts (8 GW). It is the world's first UHVDC project to employ an innovative hybrid cascaded transmission technology, combining conventional line-commutated (LCC) with multi-level voltage source (MMC VSC) technologies into one scheme.

Project Route and Stations

The transmission line begins at the Butuo converter station in Liangshan Prefecture, Sichuan Province, and terminates at the Changshu converter station in Jiangsu Province. The sending-end converter station is located at Baihetan, while the receiving-end converter station is in Zhebei.

Advanced Technologies

One of the project's notable features is its use of controllable self-recovery energy dissipation devices, which provide millisecond-level energy balancing. This technology allows the hybrid UHVDC link to quickly switch from a dependent grid to a supporting grid, enhancing the overall stability and flexibility of the power transmission system.

The Baihetan-Jiangsu UHVDC project incorporates advanced technologies to address technical challenges. It uses UHVDC classic valves for efficient long-distance power transmission with low losses, while the VSC-based HVDC technology helps stabilize the AC grid at the receiving end. The project also employs DC breakers and high-voltage live tank and dead tank breakers to enhance safety, reliability, and efficiency.

Environmental Impact

The Baihetan-Jiangsu UHVDC link deliversr more than 30 billion kilowatt-hours (kWh) of clean electricity annually. This significant power transmission capability contributes to reducing coal consumption by approximately 14 million tons per year and decreasing carbon dioxide emissions by over 25 million tons annually.

Strategic Importance

The project plays an important role in China's west-to-east power transmission strategy, helping to balance electricity supply and demand across different regions of the country. It enables the efficient transfer of surplus electricity from the hydropower-rich southwestern regions to the energy-intensive eastern provinces, supporting economic growth and promoting sustainable development.

Technological Significance

From a technical standpoint, the Baihetan-Jiangsu UHVDC project represents a significant advancement in power transmission technology. Its hybrid design and high voltage rating push the boundaries of HVDC transmission, setting new standards for efficiency and capacity in long-distance power transfer.