PROJECT TITLE :

Modular Multilevel Converter DC Fault Protection - 2017

ABSTRACT:

High-voltage direct current (HVDC) grids will require the development of dc protections that give quick fault isolation and minimize the disturbance caused to the present ac power networks. This paper investigates how the dc fault recovery performance of a [*fr1]-bridge modular multilevel converter (HB-MMC) is impacted by totally different dc protection design decisions. An HB-MMC point-to-point HVDC system that is protected with dc circuit breakers (CBs) is simulated on a true-time digital simulator using detailed switch models of the converters and switch gear. A dc CB controller has been developed and implemented in an exceedingly software-in-the-loop fashion, and has been made accessible free for download. A novel blocking scheme for the HB-MMC is proposed, that limits the potential dc-aspect fault current, benefiting dc switch gear. A comparison of circulating current controllers shows that the quality d -q controller is probably to be unsuitable for fault studies. Finally, benchmarking shows that a forty eight% reduction in power-flow recovery time and a ninety% reduction in the energy dissipated in the circuit breaker will be achieved, together with other edges, relying on the protection style.