Protection and Control of Smart DC Distribution Power System
Recent developments in distributed renewable generation and energy storage system have given rise to the concept of DC microgrid as a promising solution to enhance the resilience of smart distribution power network with high penetration of renewable power and electric vehicle demands. By connecting the DC links of renewable generations, energy storage system and possible loads interfaced by power electronics converters, low voltage DC solutions can effectively reduce the one-off cost and boost system efficiency. Since the time constants for DC control and protections are very close, a comprehensive point of view has to be taken considering protections, converter design and operational control all together. So far, the energy management and operational control schemes of DC microgrid has been intensively explored though, the protections of DC microgrid is far from mature comparing with its AC counterpart, which is the main bottleneck against practical industrial implementations. Therefore, it is crucial to develop a cost-effective protection solution to ensure reliable operation of a low-voltage dc microgrid. Further, there is also a need to investigate how a DC microgrid system can be effectively incorporated into an existing distribution network to enhance the resilience of the grid.