High Voltage Direct Current (HVDC) Transmission Technology

High Voltage Direct Current (HVDC) transmission is an efficient long-distance power transmission technology, particularly suitable for inter-regional grid interconnection and large-scale renewable energy transmission. Compared to traditional AC transmission, HVDC offers lower losses and enhanced stability over long distances, making it especially advantageous for submarine cable applications or connections between grids with different frequencies.

The core technology involves converter stations that transform AC power to DC for transmission, then invert it back to AC at the destination. Key technical components include thyristor-based converters or IGBT-based voltage source converters (VSCs), which implement sophisticated control algorithms for power flow regulation and system stability. HVDC systems typically incorporate PID controllers for maintaining DC voltage and power balance, with protection logic handled through programmable logic controllers (PLCs).

The advantages of HVDC include reduced line losses, improved grid controllability, and support for asynchronous grid interconnections. With the growing adoption of renewable energy generation, HVDC technology plays a crucial role in enabling global energy interconnections, often implemented through modular multilevel converters (MMCs) that provide superior harmonic performance and fault ride-through capabilities.