Comparison of Static VAR Compensator (SVC) vs Static Synchronous Compensator (STATCOM)
Principle of Operation
Static VAR Compensator (SVC) is the shunt-connected thyristor-controlled reactor (TCR) and thyristor-switched capacitor (TSC) to control the VAR generation and absorption by controlling the reactive admittance.
Static Synchronous Compensator (STATCOM) is a shunt-connected voltage source converter-based VAR generator to control the VAR generation and absorption.
Operating Characteristics
Fig 1 shows the V-I characteristics of STATCOM and SVC. The STATCOM can be operated for a full output current range even for low system voltage conditions (for example, 0.2 per unit). Therefore, the maximum capacitive and inductive current of the STATCOM can be achieved for the full AC system voltage.
In the SVC, the maximum capacitive compensation current is decreased when the AC system voltage is reduced. Therefore, the STATCOM provides better voltage support than the SVC under reduced system voltage conditions when a large system disturbance happens.