Applying Synchronous Condenser for Damping Provision in Converter-dominated Power System

The dynamic characteristics of converter-dominat‐d systems are governed by the controls of power converters and the interactions among the converter systems and conventional alternators. Frequency oscillations can appear during dynamic operating conditions caused by the phase-locked loop dynamics and the interactions among the converter control systems. The oscillations may be poorly damped that can result in reduced power generation, longer settling time or disconnections of sensitive components. It is foreseeable that damping services will be critical for grid stabilization in the future with high penetration of renewable generation. In this work, synchronous condensers are evaluated and applied for providing damping services to the grid in post-event conditions. An innovative supplementary controller for the automatic voltage regulator of synchronous condensers is proposed to improve frequency stabilization in a converter dominated system after disturbances. Utilizing local and remote measurements, synchronous condensers are able to modulate the reactive power output hence the terminal bus voltage, which further impacts on the power flow in the system, therefore, it provides damping to the frequency oscillations. The control is implemented on an industrial level hardware platform and the performance is verified by hardware-inthe-loop simulation.