Impacts of inverter-based distributed generation control modes on short-circuit currents in distribution systems

With the rapid increase in using New/Renewable Energy Resources, Inverter-based Distributed Generations (IBDG) are more and more widely installed in electric power systems. However, the limited short-circuit current contributed from these generators should be noted for the operation of the protection systems. This paper analyzes the changes of short-circuit currents in distribution system with the penetration of IBDG and illustrates how the inverter control modes affect the response of the IBDG. Then, an adaptive algorithm is proposed for short-circuit currents calculation. A simulation in Matlab/Simulink environment comprehensively compares the changes of short-circuit current in the system before and after installing IBDG as well as verifies the proposed algorithm.