Energy reliability enhancement of a data center/wind hybrid DC network using superconducting magnetic energy storage

The progressive penetrations of sensitive renewables and DC loads have presented a formidable challenge to the DC energy reliability. This paper proposes a new solution using series-connected interline superconducting magnetic energy storage (SCI-SMES) to implement the simultaneous transient energy management and load protection of DC doubly-fed induction generator (DC-DFIG)/internet data center (IDC) composited medium-voltage direct-current (MVDC) network. The SCI-SMES mainly consists of two current source converters (CSCs) sharing a common SMES link. It can implement the transient energy conversion and interaction between sensitive sources and loads in two individual DC feeders, even they are with different voltage and current levels. To prove the above-mentioned functions, a kW-class experimental SCI-SMES prototype is established. For actual renewable energy scenarios, six different cases of power flow and energy interaction between DC-DFIG and IDC are presented in this paper, and a MW-class with SCI-SMES-integrated hybrid DC network is built in simulation for verification. A techno-economic assessment, considering capital investment, operating cost, and financial losses of voltage sags, shows that the total investment payback period is in the range of 5.44–18.41 years, which proves the SCI-SMES has both economic and technical advantages in large-scale data centers and renewable generation sectors. •Series-connected interline superconducting magnetic energy storage (SCI-SMES).•Short-term power flow and long-term energy interaction among multiple DC lines.•Energy management strategy and static/dynamic economic feasibility for the SCI-SMES.•KW-class experiments and MW-class simulations for SCI-SMES studies.•The SCI-SMES offers technically/economically merits for DC renewable networks.