suurjännitetasavirtasiirto

suurjännitetasavirtasiirto, often abbreviated as HVDC, is a method of transmitting electrical power using direct current (DC). This is in contrast to the more common high-voltage alternating current (HVAC) systems. HVDC technology is particularly advantageous for long-distance power transmission and for interconnecting asynchronous AC grids. The key components of an HVDC system include converter stations at both ends of the transmission line. These stations convert AC power to DC for transmission and then convert it back to AC at the receiving end.

The primary advantage of HVDC is its efficiency over long distances. Unlike AC, DC power transmission experiences lower losses, especially for very long lines or when transmitting large amounts of power. This is due to the absence of reactive power and skin effect, which are inherent to AC transmission. Furthermore, HVDC can transmit more power over the same right-of-way compared to AC. Another significant benefit is the ability to connect AC systems that operate at different frequencies or are not synchronized. This is crucial for international power grids and for integrating diverse renewable energy sources.

HVDC systems are also beneficial for underwater or underground transmission, where the capacitance of AC cables can limit power transfer. For shorter distances, however, the cost of the converter stations can make HVDC less economical than HVAC. The development of thyristor-based converter technology has significantly improved the efficiency and reliability of HVDC systems, making them a viable and increasingly important option for modern power grids.