Static VAr Compensator Studies

What is a Static Var Compensator (SVC)?

A Static Var Compensator (SVC) is a shunt-connected device designed to regulate reactive power by dynamically generating or absorbing vars to maintain or control specific electrical system parameters, typically bus voltage.

SVC components include:

Thyristor-Controlled Reactor (TCR): Continuously adjustable reactance using partial conduction of thyristor valves.
Thyristor-Switched Capacitor (TSC): Switches capacitors ON/OFF via thyristor valves, often paired with damping reactors.
Thyristor-Switched Reactor (TSR): Switches reactors ON/OFF using thyristor valves.

Importance of Static Var Compensators (SVC)

SVC systems are critical for:

Voltage Control: Steady-state and dynamic voltage regulation, even at points distant from the SVC connection.
Voltage Stability: Enhancing system voltage during normal and disturbed conditions.
System Capacity: Increasing circuit capacity limited by low receiving-end voltage or stability constraints.
Disturbance Recovery: Restoring bus voltage after faults or load rejection events.
Power Oscillation Damping: Mitigating oscillations (0.2–2.0 Hz) to improve dynamic stability.
Reactive Power and VAR Control: Coordinating reactive power contributions from SVCs and other equipment.
Variable Load Correction: Rapid adjustment for power factor, load imbalances, and harmonic filtering.

How Do We Perform SVC Studies?

Data Collection: Gather relevant information, including single-line diagrams (SLD), SVC specifications, and study-specific data (e.g., load flow, short circuit, transient, harmonic, stability).
System Modeling: Build detailed models of the SVC and the power system using ETAP, PSS®E, or PSCAD/EMTDC software.
Simulation Scenarios: Develop case studies tailored to client requirements and system conditions.
Reporting: Prepare and deliver a comprehensive technical report with study results and recommendations.

Applicable Standards for SVC Studies

IEEE Std 1031™-2011: Guide for the Functional Specification of Transmission Static Var Compensators.
IEC 61954: Testing of Thyristor Valves in Static VAR Compensators.