Picture of athlete cycling

Open Access research with a real impact on health...

The Strathprints institutional repository is a digital archive of University of Strathclyde's Open Access research outputs. Strathprints provides access to thousands of Open Access research papers by Strathclyde researchers, including by researchers from the Physical Activity for Health Group based within the School of Psychological Sciences & Health. Research here seeks to better understand how and why physical activity improves health, gain a better understanding of the amount, intensity, and type of physical activity needed for health benefits, and evaluate the effect of interventions to promote physical activity.

Explore open research content by Physical Activity for Health...

Active control of DC fault currents in DC solid-state transformers during ride-through operation of multi-terminal HVDC systems

Li, Rui and Xu, Lie and Yao, Liangzhong and Williams, Barry (2016) Active control of DC fault currents in DC solid-state transformers during ride-through operation of multi-terminal HVDC systems. IEEE Transactions on Energy Conversion. ISSN 0885-8969

Text (Li-etal-IEEETEC2016-active-control-of-dc-fault-currents-in-dc-solid-state-transformers)
Li_etal_IEEETEC2016_active_control_of_dc_fault_currents_in_dc_solid_state_transformers.pdf - Accepted Author Manuscript

Download (861kB) | Preview


When a pole-to-pole dc fault occurs in a multi-terminal HVDC system, it is desirable that the stations and dc solid-state transformers on healthy cables continue contributing to power transfer, rather than blocking. To reduce the fault current of a modular multilevel converter based dc solid-state transformer, active fault current control is proposed, where the dc and ac components of fault arm currents are regulated independently. By dynamically regulating the dc offset of the arm voltage rather than being set at half the rated dc voltage, the dc component in the fault current is reduced significantly. Additionally, reduced ac voltage operation of the dc solid-state transformer during the fault is proposed, where the ac voltage of transformer is actively limited in the controllable range of both converters in the transformer to effectively suppress the ac component of the fault current. The fault arm current peak and the energy absorbed by the surge arrester in the dc circuit breakers are reduced by 31.8% and 4.9% respectively, thereby lowering the capacities of switching devices and circuit breakers. Alternatively, with the same fault current level, the dc-link node inductance can be halved by using the proposed control, yielding lowered cost and volume. The novel active fault current control mechanism and the necessary control strategy are presented and simulation results confirm its feasibility.