Reconfigurable DC Links for Restructuring Existing Medium Voltage AC Distribution Grids

2018 IEEE 18th International Power Electronics and Motion Control Conference (PEMC)

Qin

et al. 2018

Self Cite

Back-to-back Modular multilevel converters (MMC) for medium voltage dc (MVDC) distribution link applications offer exciting opportunities due to its superior harmonic performance and high efficiency. Based on the steady state equations, it is shown that under specific active and reactive power operation, an increase in dc link voltage can be achieved without necessarily increasing the voltage seen by the MMC submodule components. Using steady state loss model, it is proved that the converter operating efficiency can be improved if this concept is applied.

Section: B Background On the Project Objectivesmentioning

confidence: 86%

Modular Multilevel Converter Performance with Dynamic MVDC Distribution Link Voltage Rating

2018 IEEE 18th International Power Electronics and Motion Control Conference (PEMC)

Qin

et al. 2018

Self Cite

“…Our project explores the potential of flexible dc links in restructuring existing medium voltage ac grids [1]. The increasing focus of dc in medium voltage distribution is evident in recent projects across the world [1]- [6]. For example, a Whitepaper by Siemens [7] presents their interest in adopting dc based technologies for designing future and flexible distribution grids.…”

Section: A Mvdc In Distribution Network Expansionmentioning

confidence: 99%

“…Medium voltage distribution systems are usually dominated by relatively short distance power transfer at 10-66 kV ac [1]. The role of dc is important in capacity enhancement of refurbishing existing grid infrastructure [8].…”

Section: B Backgroundmentioning

confidence: 99%

“…In case of overhead lines, economics of compact power transmission plays a role in choosing dc distribution links [3]. For underground cables, avoiding digging and installation of new insulated conductors could be an important consideration [1]. The dc voltage enhancement factor is more liberally chosen in case of overhead lines leading to 2-3 times increase in capacity, even though some modifications in the towers and supporting structure maybe necessary [12].…”

Section: A Overhead and Underground Conductorsmentioning

confidence: 99%

See 1 more Smart Citation

Reliability, Efficiency and Cost Trade-offs for Medium Voltage Distribution Network Expansion using Refurbished AC-DC Reconfigurable Links

2018 International Symposium on Power Electronics, Electrical Drives, Automation and Motion (SPEEDAM)

Bauer

2018

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The role of MVDC links for distribution network expansion is important. The distribution network operators (DNOs) can maximize the power transfer capacity of existing grid infrastructure during (n-1) contingencies using reconfigurable parallel ac-dc architecture. In addition this concept involves a range of efficiency, reliability and economic trade-offs. The object of this paper is to present a discussion on the emerging choices involved in adopting a parallel ac-dc reconfigurable link architecture in designing future and flexible power grids.

“…Need for compact, socioeconomically viable and efficient operation has led to pursuit of research on alternate ways of tackling this problem [2], [3]. A good discussion on anticipated challenges in restructuring medium voltage ac grids and the roadmap for the role of reconfigurable dc links is offered in [4].…”

Section: A Problem Descriptionmentioning

confidence: 99%

AC distribution grid reconfiguration using flexible DC link architecture for increasing power delivery capacity during (n-1) contingency

Kontos

2017 IEEE Southern Power Electronics Conference (SPEC)

et al. 2017

Self Cite

A practical issue faced by today's ac grid is the rapidly growing power demand on its aging infrastructure. One possibility to maximize the capacity of the existing infrastructure is to refurbish the ac links to operate under dc conditions using modular multilevel converters. In this paper, the idea is applied to restructure an actual medium voltage distribution system. Further, a systematic reconfiguration strategy is proposed to maintain high power delivery capacity even during (n-1) contingency. Contingency analysis is carried out for faults in different system components of the distribution grid. Towards this goal, novel concepts such as reconfigurable switch, dc link converter bypass and flexible dc to ac operational transition are proposed.