HVDC transmission lines
Electricity is delivered to homes, schools, hospitals, businesses and industries through an integrated system of generation facilities, power lines and substations. Transmission lines carry electricity from where it is generated to where it is needed. The transmission network enables a large amount of power to travel long distances.
High-voltage direct current lines are like an interstate highway for power. HVDC lines help bolster the electric grid by efficiently moving large amounts of power.
HVDC lines are a cost-effective, efficient option for moving large amounts of power over long distances. They can easily be added to the electric grid with converter substations and allow the direction and amount of power to be controlled. Instead of the traditional three phases, or three wires, in an alternating current line, HVDC lines use two wires, positive and negative, to move power.
How HVDC lines integrate with the AC transmission grid
Power is converted from alternating current to direct current and “stepped up” to higher voltages at a converter substation. The power then moves efficiently along HVDC lines with minimal electric losses. It is then converted once again to AC and reduced to lower voltages at the endpoint substation, which allows electric distribution companies to bring the power to homes and businesses.