<?xml version="1.0" encoding="ISO-8859-1"?><article xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
<front>
<journal-meta>
<journal-id>0121-7488</journal-id>
<journal-title><![CDATA[Ciencia en Desarrollo]]></journal-title>
<abbrev-journal-title><![CDATA[Ciencia en Desarrollo]]></abbrev-journal-title>
<issn>0121-7488</issn>
<publisher>
<publisher-name><![CDATA[Universidad Pedagógica y Tecnológica de Colombia]]></publisher-name>
</publisher>
</journal-meta>
<article-meta>
<article-id>S0121-74882025000200073</article-id>
<article-id pub-id-type="doi">10.19053/uptc.01217488.v16.n2.2025.18109</article-id>
<title-group>
<article-title xml:lang="en"><![CDATA[Conexión óptima a tierra del neutro en redes de CC bipolares con carga asimétrica mediante una aproximación convexa cuadrática mixta-entera]]></article-title>
<article-title xml:lang="es"><![CDATA[Optimal neutral grounding in bipolar DC networks with asymmetric loading through a mixed-integer quadratic convex approximation]]></article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Montoya]]></surname>
<given-names><![CDATA[Oscar Danilo]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Gil-González]]></surname>
<given-names><![CDATA[Walter]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Garces]]></surname>
<given-names><![CDATA[Alejandro]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
</contrib-group>
<aff id="Af1">
<institution><![CDATA[,Universidad Distrital Francisco José de Caldas  ]]></institution>
<addr-line><![CDATA[Bogotá ]]></addr-line>
<country>Colombia</country>
</aff>
<aff id="Af2">
<institution><![CDATA[,Universidad Tecnológica de Pereira  ]]></institution>
<addr-line><![CDATA[Pereira ]]></addr-line>
<country>Colombia</country>
</aff>
<pub-date pub-type="pub">
<day>00</day>
<month>12</month>
<year>2025</year>
</pub-date>
<pub-date pub-type="epub">
<day>00</day>
<month>12</month>
<year>2025</year>
</pub-date>
<volume>16</volume>
<numero>2</numero>
<fpage>73</fpage>
<lpage>81</lpage>
<copyright-statement/>
<copyright-year/>
<self-uri xlink:href="http://www.scielo.org.co/scielo.php?script=sci_arttext&amp;pid=S0121-74882025000200073&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.co/scielo.php?script=sci_abstract&amp;pid=S0121-74882025000200073&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.co/scielo.php?script=sci_pdf&amp;pid=S0121-74882025000200073&amp;lng=en&amp;nrm=iso"></self-uri><abstract abstract-type="short" xml:lang="en"><p><![CDATA[Abstract This work analyzes the optimal grounding of bipolar DC networks with asymmetric loading through a convex optimization model. The power flow equations are represented as convex-conic constraints with binary variables introduced to define the nodes where solid grounding is most suitable to minimize power loss. The problem belongs to the family of mixed-integer quadratic convex (MIQC) models, which is solvable with a combination of the branch-and-cut and the interior point method. The model ensures global optimum due to the convexity of the solution space for each combination of the binary variables. Numerical experiments in bipolar DC networks with 4-, 21-, 33-, and 85-node demonstrate the effectiveness of the optimal grounding procedure regarding power loss minimization. All the computational validations were carried out in the MATLAB programming environment using the convex disciplined tool (CVX) and the Gurobi solver.]]></p></abstract>
<abstract abstract-type="short" xml:lang="es"><p><![CDATA[Resumen Este trabajo analiza la conexión a tierra óptima de redes de CC bipolares con carga asimétrica mediante un modelo de optimización convexa. Las ecuaciones de flujo de potencia se representan como restricciones cónicas convexas con variables binarias introducidas para definir los nodos donde la conexión a tierra sólida es más adecuada para minimizar la pérdida de potencia. El problema pertenece a la familia de modelos convexos cuadráticos mixtos enteros (MIQC, por sus siglas en inglés), los cuales son resolubles mediante una combinación del método de ramificación y corte y el método de punto interior. El modelo garantiza el óptimo global debido a la convexidad del espacio de soluciones para cada combinación de las variables binarias. Los experimentos numéricos en redes bipolares de CC con 4, 21 y 33 nodos demuestran la efectividad del procedimiento de conexión a tierra óptima en la minimización de pérdidas de potencia. Todas las validaciones computacionales se realizaron en el entorno de programación MATLAB utilizando la herramienta de disciplina convexa (CVX) y el solucionador Gurobi.]]></p></abstract>
<kwd-group>
<kwd lng="es"><![CDATA[Redes bipolares de CC asimétricas]]></kwd>
<kwd lng="es"><![CDATA[conexión a tierra óptima del neutro]]></kwd>
<kwd lng="es"><![CDATA[reformulación cónica del flujo de potencia]]></kwd>
<kwd lng="es"><![CDATA[modelo de programación cónica de segundo orden mixto entero]]></kwd>
<kwd lng="es"><![CDATA[minimización de pérdidas de potencia]]></kwd>
<kwd lng="en"><![CDATA[Asymmetric bipolar DC networks]]></kwd>
<kwd lng="en"><![CDATA[optimal neutral grounding]]></kwd>
<kwd lng="en"><![CDATA[conic power flow reformulation]]></kwd>
<kwd lng="en"><![CDATA[mixed-integer second-order cone programming model]]></kwd>
<kwd lng="en"><![CDATA[power loss minimization]]></kwd>
</kwd-group>
</article-meta>
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