HVDC Full Form | Full Form of HVDC

High Voltage Direct Current Transmission

HVDC stands for High Voltage Direct Current Transmission.
It refers to the massive transmission of electricity within the form of DC over long distances by means of submarine cables or overhead transmission lines.
This method of transmitting electricity over long distances is preferred over HVAC as HVDC lines are less expensive and losses also are less as compared to HVAC transmission.
HVDC is additionally popularly referred to as Electrical Super Highway or Power Super Highway.

How does HVDC transmission work ?

Ac power is generated within the generating station.
The AC power needs to be converted into DC power before starting the transmission of electricity as this system uses Direct Current for the transmission of large amounts of electricity. So, this system may be a combination of a DC (Direct Current) circuit with two power electronics converters at each end of the circuit for AC to DC and DC to Ac conversion.
In other words, there's a rectifier terminal at one end of the HVDC substation and an inverter terminal at another end.
The DC power moves through the overhead lines and at the user end an inverter is placed in order to convert DC power into AC.
The power of the end which sends the electricity and user end is usually equal i.e. input power is equal to output power.
A single transmission line with a converter at both the ends is termed as two-terminal DC system.
When there are two or more converter stations and DC transmission lines it's referred to as multi-terminal DC substation.

Basic Components of HVDC

Converters : They're used for the conversion of AC to DC and DC to AC.
Smoothing Reactors : They're connected serial with the HVDC transmission lines.
Electrodes : They're used to connect the system to earth.
Harmonic filters : They're used to minimize the voltage and current distortion of the converters.
DC Lines : It's the overhead transmission lines.
Reactive Power Supplies : It helps maintain voltage to deliver active power through transmission lines.
AC Circuit Breakers : They're used to clear the faults within the transformer and to disconnect the DC link.