Abstract:
The fault characteristics of multi-converter DC system are complex and variable. How to use fault transient information for fault characteristic analysis and protection s...Show MoreMetadata
Abstract:
The fault characteristics of multi-converter DC system are complex and variable. How to use fault transient information for fault characteristic analysis and protection setting is one of the challenges faced by the development of DC power distribution system. In this article, the high-frequency characteristics of faults in DC systems are analyzed. Then based on the transient fault circuit analysis method, the frequency domain impedance model of typical converters is obtained. The model established in the higher frequency band is not affected by the control strategy and can provide a stable impedance value, which lays a theoretical foundation for the protection principle. At the same time, the characteristics of the high frequency impedance superposition of multi-converter system are also given, which provides a basis for system-level protection setting and coordination. Finally, the DC power distribution system model is established in PSCAD/EMTDC for simulation, and the results prove the accuracy and validity of the DC system model.
Published in: IEEE Transactions on Smart Grid ( Volume: 12, Issue: 1, January 2021)