HVDC Transmission System Layout
The block diagram of the HVDC transmission system
There are three types of filters used which are:
1. AC Filters:
These are passive circuits used to provide how impedance, shunt paths for AC harmonic currents. Both tuned and damped filter arrangements are used.
2. DC Filters:
These are similar to AC filters and are used for the filtering of DC harmonics.
3. High Frequency (RF/PLC) Filters:
These are connected between the converter transformer and the station AC bus to suppress any high-frequency currents. Sometimes such filters are provided on high-voltage DC bus connected between the DC filter and DC line and also on the neutral side.