Instituto Tecnológico de Morelia

About: Instituto Tecnológico de Morelia is a education organization based out in Morelia, Mexico. It is known for research contribution in the topics: Electric power system & AC power. The organization has 498 authors who have published 572 publications receiving 4600 citations.

Active correlation technology applied to maintenance program based on voltage sags control

Abstract: This paper presents an Active Correlation Technology (ACT) for voltage sag detection and control. ACT is a conceptual architecture developed by IBM and can be successfully implemented to manage maintenance activities of distribution networks. As an instrument, maintenance clearly impacts on system reliability and quality of supply, i.e., very limited maintenance will result in an excessive number of costly failures and poor system performance, and therefore, reliability and quality of supply are degraded; done often, both reliability and quality of supply may improve but the cost of maintenance will sharply increase. Efficient maintenance schemes consider condition monitoring and maintenance activities are performed when a threshold pattern is violated. In this paper, a correlation engine is proposed to set voltage sag threshold patterns to detect abnormal sag incidence on MV feeders and trigger alarms to indicate the need for maintenance activities. The central ideas are validated with records obtained from a medium voltage circuit operated by one of the distribution divisions of the Mexican utility.

Analysis and synthesis Peaucellier mechanism

Abstract: A straight line motion is a common application in engineering design and manufacture. The Peaucellier mechanism generates exact straight lines, meeting some restrictions among their links dimensions and the input angle. The mechanism has eight links, but due to those initial restrictions, only requires to find relations among three of its eight links and rotation angle. This paper explains the process employed to find those relations using mechanism singular configurations, used to determine its links operational ranges, maximum displacement and rotation angle. Firstly, two computer programs were developed taking in account the equations obtained from the kinematic analysis. One of them simulates the mechanism motion and the other one locates every point on the straight line. Secondly, all data are analyzed and tested ensuring that the mechanism works within its limits. Simultaneously, another kinematic analysis was made to find the relationship between the maximum displacement and the link lengths for a particular case.

A Novel Framework Based on Mixed-Integer Linear Programming to Restore a Disintegrated Power Grid after Cascading Failures

Abstract: Electric power systems are prone to disturbances and contingencies, which can trigger cascading failures with severe consequences for society. These undesirable events could disintegrate the electrical infrastructure in areas with disconnected elements. In this article, we propose a novel procedure to restore a collapsed power grid composed of multiple islands and isolated assets. The framework developed identifies the power lines to be closed during the electrical network recovery stages. In the latter, link overload limits and generation thresholds are taken into account. Two disintegrated networks based on the well-known IEEE 57-bus test system are built to demonstrate the performance of our proposal. In summary, this methodology provides a solution to recover the power system optimally and reliably.

Thermo-mechanical-microstructural simulation of double-pass welding process in a TWIP steel by FE formulation and probabilistic model

Abstract: This research work developed a decoupled thermo-mechanical-microstructural (TMM) numerical framework to simulate a multi-pass welding process. The numerical framework was applied to evaluate the effect of operating parameters on the weldability of a twinning induced plasticity (TWIP) steel considering metallurgical defects and the weld joint’s mechanical properties. The thermo-mechanical model was solved numerically using a finite element model (FEM). After that, the simulation of the thermo-microstructural field was performed through a combined probabilistic approach Monte Carlo (MC)-Voronoi tessellation. The staggered solution approach and the optimized FE macro-scale mesh further improved the convergence and reduced computing time. The correlation of TMM model estimations with thermal history measurements and mechanical and metallographic characterizations helped explain the variation of post-welding mechanical properties. The nature of residual stresses in the TWIP steel joint was correlated with the heat flux in the critical weld regions. The thermal gradients were also correlated with the weld regions that underwent grain growth and grain size reduction. The grain growth simulation performed by the MC-Voronoi model was in good agreement with the hardness reduction in the heat-affected zone (HAZ). The grain size distribution in the HAZ produced an unexpected tensile elongation.

FE-Based Application for the Evaluation of Core-Losses in Distribution Transformers

Abstract: This paper describes a finite-element (FE) based application for the numerical evaluation of core-losses in distribution transformer. The specific application is centered around a method that permits the generation of software applications for a variety of user/customer defined problems and makes use of the FE method in order to solve them. A variety of problems are considered such as electromagnetic or thermal, steady state or transient, linear or non-linear, and two-dimensional (2-D) or three-dimensional (3-D). The present manuscript focuses on one such application and more specifically on the problem of core-losses evaluation in oil-immersed, wound core, distribution transformers, both single-phase and three-phase. Finally, the core-losses of a single-phase wound core transformer are computed using the “CORELOSS” application and they are compared with results obtained with a commercial FE package.