Control Study of Enhanced STATCOM for Supercapacitor Applying Virtual Synchronous Generator Control

The enhanced static synchronous compensator (E-STATCOM), which is equipped with a supercapacitor and can output active power, is attracting attention as a compensator that can both suppress grid voltage fluctuations and maintain short term frequency during transients. The authors propose a virtual inertia control based on current control-type converters. The method can suppress overcurrent and manage the DC voltage of the converter, which are issues with the typical grid forming control employing voltage control-type converters. The proposed control configuration is based on an established currentcontrolled STATCOM. However, a virtual synchronous generator control can be achieved simply by adding to the DC voltage reference of the conventional STATCOM control. The simulation results show that it is possible to achieve continuous operation for the three-phase line to ground fault, and STATCOM’s active and reactive power outputs are possible to suppress system oscillations after the fault is cleared.