ما هي الفروقات بين High Voltage Direct Current Transmission و High Voltage ِ Alternate Current Transmission?

Despite alternating current being the dominant mode for electric power transmission, in a number of applications, the advantages of HVDC makes it the preferred option over AC transmission.

Examples include:

·         Undersea cables where high capacitance causes additional AC losses (e.g., the 250-km Baltic Cable between Sweden and Germany).

·         Endpoint-to-endpoint long-haul bulk powertransmission without intermediate taps, for example, in remote areas.

·         Increasing the capacity of an existing power grid in situations where additional wires are difficult or expensive to install.

·         Allowing power transmission between unsynchronized AC distribution systems.

·         Reducing the profile of wiring and pylons for a given power transmission capacity, as HVDC can carry more power per conductor of a given size.

·         Connecting a remote generating plant to the distribution grid; for example, the Nelson River Bipole line in Canada (IEEE 2005).

·         Stabilizing a predominantly AC power grid without increasing the maximum prospective short-circuit current.

·         Reducing corona losses (due to highervoltage peaks) compared to HVAC transmission lines of similar power.

·         Reducing line cost, since HVDC transmission requires fewer conductors; for example, two for a typical bipolar HVDC line compared to three for three-phase HVAC.

HVDC transmission is particularly advantageous in undersea power transmission. Long undersea AC cables have a high capacitance.