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Implementación de un módulo de protecciones de sobrecorriente mediante el uso del relé sel 351 para el laboratorio de protecciones eléctricas de la Universidad Técnica de Cotopaxi
(Universidad Técnica de Cotopaxi (UTC). Ciencias de la Ingeniería y Aplicadas. Electricidad, 2026-10-14) Cuenca Morales, Wilmer Rene; Freire Freire, Armando Salvador
The primary objective of the technological proposal was to implement an overcurrent protection module using SEL-351 relay for laboratory protection at Technical University of Cotopaxi. The methodology involved applied research, based on documentary, technical, and experimental procedures; regulatory criteria and the fundamentals of ANSI 50 and ANSI 51 functions were reviewed; a nine-bus electrical system was modeled in DIgSILENT PowerFactory; load currents and CT transformation ratios were analyzed; and finally, the settings were configured and transferred to the relay using ACSELERATOR QuickSet. The results determined normal currents of 339 A, 235 A, and 260 A for loads A, B, and C. For ANSI 51, secondary settings of 5.50 A, 5.09 A, and 5.67 A were established, with margins of 29.79%, 29.96%, and 30.85% relative to normal operation, using U3-U.S. Very Inverse Tpset characteristic of 0.50. For ANSI 50, secondary settings of 28.20 A, 35.76 A, and 40.91 A were configured, with a Tset of 0.00 s. Serial communication with SEL-351 was established using ACSELERATOR QuickSet, allowing Group 1 to be read, edited, and transferred. It was concluded that the developed parameterization adequately distinguishes between normal operation, time-delayed operation, and high-current operation, and links the results obtained in PowerFactory with the relay physical configuration, providing a technical tool for electrical protection practices. Furthermore, the module enhances practical training in configuration and analysis of digital protection systems Keywords: Protection settings, ANSI 50/51, electrical loads, SEL-351 relay, overcurrent.
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Optimización en tiempos de operación en la coordinación del Relé 51
(Universidad Técnica de Cotopaxi (UTC). Ciencias de la Ingeniería y Aplicads. Electricidad, 2026-10-14) Portilla Mora, Javier Alejandro; Solórzano Sánchez, Erick Elian; Proaño Maldonado, Xavier Alfonso
In the present paper, the optimization of operating times of the 50/51 relay in a radial system was carried out using a Mixed-Integer Linear Programming (MILP) model within a Python–DIgSILENT PowerFactory co-simulation environment, which enabled the automation of the coordination. The Python algorithm extracted the topology, load currents, and short circuits. The linearization of the curves along with the HiGHS solver allowed minimizing the time dial settings while maintaining the required coordination time margin. The model dynamically assigned Overload Factors, examined the instantaneous unit 50 to avoid overreach, and accounted for faults involving Delta-Star connected transformers. The methodology was validated in the CIGRE MV and IEEE 33-bus systems equipped with ABB Relion REF615 and Siemens SIPROTEC 7SJ62 relays respectively, using the IEC Normal Inverse curve and the ANSI Normally Inverse curve, where the results showed selectivity in all coordination pairs for an established discrimination margin. In the comparative analysis of the results between the curves, a 34.05% reduction in the sum of operating times was evidenced in the ANSI curve compared to the IEC curve due to the characteristics of each of them.
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Evaluación técnica de la calidad de la energía eléctrica en los puntos de acoplamiento común (pac) de la red de baja tensión de la empresa Induacero cía. Ltda
(Universidad Técnica de Cotopaxi (UTC). Facultad de Ciencias de la Ingeniería y Aplicadas. Electricidad, 2026-10-14) Chariguaman Chiliquinga, Widynson Joel; Proaño Maldonado, Xavier Alfonso
The objective of this research was to evaluate the power quality at the Points of Common Coupling (PCCs) of the low-voltage network of the main plant of INDUACERO Cía. Ltda., through the measurement and analysis of the main electrical parameters established by the applicable technical standards. To achieve this, information on the electrical system was collected, the installed loads were characterized, and a seven-day continuous monitoring period was conducted at the main switchboards associated with the 75 kVA and 45 kVA transformers using a Fluke 435-II power quality analyzer. Additionally, a computational model was developed in ETAP to complement the analysis of the operating conditions observed in the field. The evaluation included parameters such as voltage level, voltage and current unbalance, harmonic distortion, power factor, flicker, and grounding system condition. The results showed that voltage levels, harmonic distortion, power factor, and flicker complied with the limits established by the applicable regulations. However, elevated neutral-to-ground voltage levels were identified at both PCCs, inadequate performance of the existing grounding system, significant current unbalance at PCC-A, and recurrent transformer overload conditions at PCC-B. Based on the findings obtained, technical solutions were proposed focusing on the redesign of the grounding system and the redistribution of loads to reduce the overloading of the 45 kVA transformer. The results provide a technical basis for decision-making aimed at improving the operating conditions, electrical safety, and reliability of the plant's electrical system
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Juego de roles como recurso didáctico para la comprensión de las preposiciones en el aula
(Universidad Técnica de Cotopaxi (UTC). Pujilií. Pedagogía de la Lengua y Literatura, 2026-10-19) Moya Amores, Dayana Carolina; Castillo Sacatoro, Ana Verónica; Cárdenas Quintana, Raúl Bolívar
Abstract
This article analyzes the difficulties students have in the comprehension of prepositions. The research addressed the following problem: How does role play as a teaching resource influence the comprehension of prepositions of place, time, direction, cause, and company among fourth-grade students of Basic General Education in Salcedo Canton during the 2025–2026 period? The general objective was to determine the influence of role play as a teaching resource on the comprehension of prepositions of place, time, direction, cause, and company. The study was conducted with fourth-grade students of Basic General Education at Oxford Educational Unit, located in Salcedo, Cotopaxi Province, Ecuador, during the 2025–2026 period. In the research, a quantitative approach, a deductive method, and a non-experimental design were used; that is, variables were not manipulated. A 15-item survey with a Likert scale was administered, which was used in both the pre-test and post-test. The instrument was validated by experts, professors from the Technical University of Cotopaxi, and the SPSS software, obtaining a Cronbach's alpha coefficient of 0.829. A total of 480 responses corresponding to 32 students were recorded, allowing for a complete comparison between the pre-test and post-test. In the pre-test, 64% of the responses were located in negative categories and only 15.9% in positive categories, which evidenced difficulties in the comprehension of prepositions. In the post-test, positive responses increased to 91.3% and negative responses decreased to 2.5%, evidencing a significant improvement. In conclusion, role play improved the comprehension of prepositions, demonstrating that it is an effective teaching resource for strengthening learning and communicative skills
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El discurso narrativo como herramienta didáctica para la comprensión de El Chulla Romero y Flores
(Universidad Técnica de Cotopaxi (UTC). Pujilií. Pedagogía de la Lengua y Literatura, 2026-10-19) Toaquiza Toasa, Diego David; Corrales Suárez, Nelson Arturo
The development of reading comprehension within the educational field represents a significant challenge for teachers during the instructional process. Accordingly, this research addressed the following problem: how does narrative discourse influence the comprehension of the novel El Chulla Romero y Flores by Jorge Icaza. The main objective was to analyze the influence of narrative discourse on the comprehension of this novel among first-year students of the Unified General Baccalaureate (Bachillerato General Unificado -BGU) at the Gabriela Mistral educational institution, located in the Latacunga canton, Cotopaxi province, during the 2025–2026 academic year. The study employed a quantitative, pre-experimental research design. Data collection was conducted through a written test technique, utilizing a structured pedagogical test consisting of 10 items, administered as both a pretest and a posttest. The instrument was validated by three expert professors from the Language and Literature Pedagogy program, who thoroughly reviewed and endorsed its content. Subsequently, the instrument's reliability was assessed using SPSS version 32, applying Cronbach's alpha coefficient, which yielded a reliability index of .855. The results reveal a substantial improvement in the inferential and critical analysis abilities of the 24 participating students. Notably, even for items presenting greater structural complexity, such as the analysis of narrative time, a 20.9 percentage-point increase in the correct response rate was observed. These findings confirmed that the implementation of narrative discourse as a didactic tool proves effective in enhancing comprehension of El Chulla Romero y Flores among first-year BGU students, facilitating the recognition of narrative elements and promoting progression toward more complex levels of reading comprehension