Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Evaluation of Centralized and Distributed Microgrid Topologies
  Considering Power Quality Constraints   Integration of renewable generation and energy storage technologies with
conventional generation supports increased resilience, lower-costs, and clean
energy goals. Traditionally, energy supply needs of rural off-grid communities
have been addressed with diesel-generation. But with rapidly falling renewable
generation costs, mini-grids are transforming into hybrid systems with a mix of
renewables, energy storage, and diesel-generation. Optimal design of hybrid
mini-grid requires an understanding of both the economic and power quality
impacts of different designs. Existing approaches to modeling distributed
energy resources address the economic viability and power quality impacts via
separate/loosely coupled models. Here, we extend REopt - a techno-economic
optimization model developed at National Renewable Energy Laboratory - to
consider both within a single model. REopt formulates the design problem as a
mixed-integer linear program that solves a deterministic optimization problem
for a site's optimal technology mix, sizing, and operation to minimize life
cycle cost. REopt has traditionally not constrained the power injection based
on power quality. In the work presented here, we expand the REopt platform to
consider multiple connected nodes. In order to do this, we model power flow
using a fixed-point linear approximation method. Resulting system sizes and
voltage magnitudes are validated against the base REopt model, and solutions of
established power flow models respectively. We then use the model to explore
design considerations of mini-grids in Sub-Saharan Africa. Specifically, we
evaluate under what combinations of line length and line capacity it is
economically beneficial (or technically required based on voltage limits) to
build isolated mini-grids versus an interconnected system that benefits from
the economies of scale associated with a single, centralized generation system.

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The categories of this paper are: patt-sol
29
The categories of this paper are: funct-an
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The categories of this paper are: nucl-ex
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The categories of this paper are: solv-int
35
The categories of this paper are: mtrl-th
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The categories of this paper are: comp-gas
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The categories of this paper are: cmp-lg
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The categories of this paper are: atom-ph
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The categories of this paper are: cond-mat
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The categories of this paper are: alg-geom
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The categories of this paper are: supr-con
0
The categories of this paper are: hep-ph
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The categories of this paper are: nlin
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The categories of this paper are: ao-sci
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The categories of this paper are: nucl-th
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The categories of this paper are: hep-ex