Electric Power Substations Engineering

Control and Protection System

Today’s state-of-the-art HVDC and FACTS controls fully digitized and processor based allow steady-state, quasi steady-state, dynamic, and transient control actions and provide important equipment and system protection functions. Fault monitoring and sequence-of-event recording devices are used in most power electronics stations.

Typically, these stations are remotely controlled and offer full local controllability as well. Man-machine interfaces are highly computerized, with extensive supervision and control via monitor and keyboard. All of these functions exist in addition to the basic substation secondary systems.

Fast dynamic performance is standard.

Special voltage vs. current control characteristics are used for converters in multiterminal HVDC systems to allow safe operation even under loss of interstation communication.

Furthermore, HVDC controls provide equipment and system protection, including thyristor overcurrent, thyristor overheating, and DC line fault protection. Control and protection reliability are enhanced through redundant and fault tolerant design. HVDC stations can often be operated from different control centers.