An electrode line is a component of a high voltage direct current (HVDC) transmission system. It is basically an electrical connection from a static inverter plant, which connects a ground level electrode with both anode and cathode plates. The electrode line assists the static inverter plant in its normal operations as a terminal for HVDC systems, which is a critical function as the plant is responsible for converting direct current (DC) into a three phase alternating current (AC) for commercial and residential applications. A typical static inverter terminal usually houses transformers, DC switch gears, harmonic filters, AC switch gears and capacitors.
The purpose of an electrode line in an inverter plant is to prevent the electrochemical corrosion of wires and equipment, and to steer clear of electromagnetic interference in the surrounding areas. High voltage direct current from the plant can cause the corrosion of cables, sheaths and water pipes that pass underneath the station. Electromagnetic interference can affect radio signals, telephone signals or even railway lines installed nearby. An electrode line enables utility companies to be able to locate and connect to electrodes closer to the static inverter plant using shorter cables. As a result of the electrode line, there are fewer power outages and less interference with other electrical cables.
High voltage direct current supply is a crucial infrastructure for the development of any region. Power utility companies consider them to be the backbone of electricity transmission. The major component of HVDC systems is the static inverter plant which serves as the interface for medium voltage range power transmission to homes and businesses. This is normally achieved through the use of controllable electrical valves which are configured in three phase bridges. Such a configuration has several benefits including improving the stability of alternating current systems, providing safety from voltage fluctuations and reducing the need to increase the short circuit capacity imposed on the AC switchgear.
Once a static inverter plant has been set up in a particular area, it needs to be grounded. A ground electrode cannot simply be placed at the station itself due to certain risks. For instance, a direct current may enter into the transformers through the primary neutral and cause DC saturation. As a result, the anode and cathode electrodes should be located in an area with sufficient thickness and conductivity. It should be far from human settlement as well as far from underground cables and pipelines.