@ARTICLE{ iet:/content/journals/10.1049/iet-gtd.2017.1754, author = {Shimin Xue}, author = {Chong Liu}, keywords = {loop-type DC grid;fault recovery times;blocking measure;single-terminal fault location method;voltage-source converter;steady-state currents;fault isolation scheme;fault resistances;DC circuit breakers;fault location principle;harmonic component;exact fault location function;2-step isolation scheme;DC-link capacitor;system operation restoration;transient component;fault clearance;low-voltage systems;VSC-based DC systems;rapid discharging process;steady-state harmonic component;time 160 ms;thyristors;slow charging processes;current zero-crossing point;fault current;}, ISSN = {1751-8687}, language = {English}, abstract = {The rapid discharging and slow charging processes of a DC-link capacitor in a voltage-source converter (VSC) have become the primary issues in VSC-based DC systems, resulting in greatly prolonged fault recovery times. Therefore, blocking measure for capacitors is necessary, but limits the principles of fault location being based on the transient component. Moreover, as the main bottleneck in the development of DC system protections, the DC circuit breakers (DCCBs) adopted in low-voltage systems have yet to be fully developed. Hence, it is necessary to propose a fault location principle based on steady-state currents and a fault isolation scheme based on ACCBs. This study presents a 2-step isolation scheme adopting thyristors and ACCBs to facilitate fault location and clearance. This method retains the harmonic component of the fault current and creates a current zero-crossing point. Next, a single-terminal fault location method adopting a steady-state harmonic component is used to realise the exact fault location function with different fault resistances and to restore system operation within 160 ms. The protection method economising many communication modules and DCCBs is suited for low-voltage distribution DC systems.}, title = {Fault location principle and 2-step isolation scheme for a loop-type DC grid}, journal = {IET Generation, Transmission & Distribution}, issue = {12}, volume = {12}, year = {2018}, month = {July}, pages = {2937-2943(6)}, publisher ={Institution of Engineering and Technology}, copyright = {© The Institution of Engineering and Technology}, url = {https://digital-library.theiet.org/;jsessionid=192lpg9ehfbmj.x-iet-live-01content/journals/10.1049/iet-gtd.2017.1754} }