This paper takes a systematic view on the control and protection of\ medium power DC networks in an active distribution power system considering fault current limiting, system control, and converter design. Reduced terminal capacitance and extra DC impedance are used to limit DC fault current and reduce the required converter current rating for medium power DC networks. An adaptive DC power stabilizer is proposed to alleviate possible system instability brought by the fault current limiting settings in the presence of constant power load. The effect of the current limiting method and the proposed stabilizer on DC fault current and stability enhancement are validated by simulation studies using a simple two-converter DC network and a multi terminal DC network in an active distribution power system.
- active distribution power system
- DC microgrid
- DC power system
- DC protection
- DC stabilizer