Protection methods for DC smart grid fulfilling FRT requirements

This paper describes a protection scheme for a DC smart grid adapting FRT requirements when a fault occurs in DC distributed line. Recently a smart grid has attracted attention with the introduction of renewable energies. DC distribution system has following advantages over AC conventional systems. For example, renewable energy sources are often DC output. So it is compatible with the DC transmission. Therefore, it is expected to be introduced many renewable energy sources. However, the problem is that the inverter is disconnected when a failure is detected in such a system. Therefore, this paper presents protection of DC smart grid adapted FRT requirements. The DC distribution model under consideration works in conjunction with an AC distribution system. The power system comprises wind power generators, photovoltaic generators, controllable loads, and DC loads. In order to verify the effectiveness of the proposed system, a DC distribution system model is simulated in the MATLAB/POWER SYSTEM environment.