Short-circuit currents characterization for future converter-based power systems

Short-circuit power (SCP) is an important characteristic parameter for synchronous generators (SGs)-based power system. And, SCP is calculated from initial short-circuit current (SCC). With the power system transitioning from SGs-based to converter-based power system, short-circuit behavior of the grid is changing due to different SCCs from converter-interfaced generators (CIGs). Therefore, the definition of SCP needs to be re-evaluated. To do so, this paper characterizes SCCs for CIGs-based power system with generating units modelled as current source (grid feeding) and voltage source (grid forming and SGs). SCCs definitions for CIGs in the time domain are proposed and compared with the classical definition of SCCs from SGs. In the end, the influence of change in SCC characteristics to the parameters related to planning and operation of future CIGs-based power system is discussed.