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This paper presents a proposal for the development of an automatic system correlation between two variables, one represented by the failures on the electrical distribution lines during a storm process and another one represented by atmospheric discharges (lightning) that happen in this process. Initially, in order to define if the failure is caused directly or indirectly by an electrical impact generated by lightning, a space-time correlation is proposed. With the obtained data a decision matrix is proposed, using an entropy method to assign weights to the failures in order to determine its severity and therefore its priority of attention. On the other hand, taking into account that the time window of observation is perhaps the most relevant parameter in the proposed correlation system, this article shows part of a simulation proposed for its calculation as well as the mathematical bases that were used as a support for it.

In this work the electromagnetic emissions caused by a discharge of a lightning have been modeled, considering the lightning as a short monopole antenna over a perfectly conducting ground plane. By this analogy the radiated electric and magnetic fields are calculated, and then the induced voltage is calculated in a distribution line considered as a short loop. The mathematical expression used for the calculation of the induced voltage was already proposed in a previous work and in the present work is validated by its confrontation in an simulated scenario with two known expressions for the calculation of the induced voltage, one recommended by the IEEE and developed by S. Rusck and another developed by Barbosa. On the basis of the considerations made by Rusck to obtain its expression for the induced voltage, the geometry related to the proposed expression is adapted to make it comparable with Rusck's international reference in the IEEE standard. Later, the dV_ind/dy behaviors of the three expressions in the region of near-field radiation of the lightning were analyzed, determining that the trends (which are hyperbolic) of the proposed expression and that developed by Rusck (internationally standardized in the IEEE 1410 standard) have a great similarity when the radiated fields exceed 20 m, giving validity to the proposed expression., En este trabajo se han modelado las emisiones electromagnéticas ocasionadas por la descarga de un rayo, considerando al rayo como una antena monopolo corto sobre un plano de tierra perfectamente conductor. Mediante esta analogía se calculan los campos eléctricos y magnéticos radiados, y luego se calcula la tensión inducida en una línea de distribución considerada como un lazo corto. La expresión matemática utilizada para el cálculo de la tensión inducida ya fue propuesta en un trabajo previo y en el presente trabajo es validada mediante su confrontación en un escenario simulado con dos expresiones conocidas para el cálculo de la tensión inducida, una recomendada por la IEEE y desarrollada por S. Rusck y otra desarrollada por Barbosa. Sobre la base de las consideraciones realizadas por Rusck para la obtención de su expresión para la tensión inducida, la geometría relacionada con la expresión propuesta es adaptada para hacerla comparable con el referente internacional de Rusck en la norma IEEE. Posteriormente se han analizado los comportamientos dV_ind/dy de las tres expresiones en la región de radiación de campo cercano del rayo, determinando que las tendencias (las cuales son de carácter hiperbólico) de la expresión propuesta y la desarrollada por Rusck (estandarizada a nivel internacional en la norma IEEE 1410) presentan una gran similitud cuando los campos radiados sobrepasan los 20 m, dando validez a la expresión propuesta.

El interés creciente de utilizar filtros activos de potencia para compensar las corrientes no sinusoidales producidas por las cargas no lineales ha aumentado el uso de la teoría instantánea de potencia reactiva. Sin embargo, esta teoría se puede aplicar solamente a los sistemas trifásicos de tres o cuatro conductores. Este artículo presenta una nueva definición de la potencia instantánea que puede ser aplicada a todos los sistemas polifásicos. Así, el concepto de producto tensorial es introducido para definir el tensor instantáneo de potencia y también la descomposición de la corriente en las componentes activas y reactivas sin importar el número de fases del sistema eléctrico. Finalmente, un análisis exhaustivo de casos prácticos se ha realizado a nivel de simulación, los cuales han permitido que el enfoque propuesto sea verificado.The use of the instantaneous reactive power theory is greater than before due to the increased interest to use active power filters to compensate the non-sinusoidal currents produced by nonlinear loads. However, this theory can only be applied to three-phase systems of three or four conductors. This paper presents a new definition of instantaneous power that can be applied to all multiphase systems. Thus, the concept of tensor product is introduced to define the instantaneous power tensor and also the current decomposition in active and reactive components regardless of the number of phases of the power system. Finally, an exhaustive analysis of practical cases has been carried out at a simulation level which verified the proposed approach.

Virtually every engineering development for control systems is tested by simulation to predict performance. However, the final use of an algorithm is in its application in a real time system. Development tools using a DSP and Simulink RTW can be performed with real-time simulations (i.e. simulation interacting with physical plant). Testing the speed control loop of a DC motor with permanent magnets has thus been developed to appreciate the considerable advantages offered by these tools.

This paper presents the results of EMI reduction techniques applied to power electronic converters. The techniques applied included shielding control and power signals, separating power system references regarding reference for instrumentation and measurement signals, implementing analog filters and configuring an appropriate switch trigger system for electronic power to decrease shifting EMI emissions to the maximum. This paper presents the results before and after applying the techniques to reduce interference. The results were also veryfied by using two real time control strategies rapid control prototyping (RCP). En este artículo se presentan los resultados de la aplicación de algunas técnicas de reducción de EMI en convertidores electrónicos de potencia. Las técnicas aplicadas incluyen el apantallamiento de señales de control y de potencia, la separación de las referencias del sistema de potencia de las señales y medidas, la implementación de filtros análogos y la configuración de un adecuado sistema de disparo, de tal forma que se disminuyan al máximo las emisiones tipo IEM. En este artículo se presentan los resultados obtenidos antes y después de aplicar las técnicas de reducción de interferencias. Además los resultados son verificados usando dos técnicas de control en tiempo real RCP (Rapid Control Prototy- ping).

This paper discusses the definition of active and reactive power in wavelet domain. Different definitions for three-phase power may cause significant changes in the measurement equipment topology. The simple phase shift using the Akagi method between current and voltage for reactive power measurement is discussed. A new power quality analysis technique (pqAT) is proposed.

This paper presents a new theory to improve and assess the quality of electrical power. The theory is based on the tensor product between voltage vectors and n-phase currents. This new definition allows the estimate of reference currents for the control of active power filters “APFs” in multiphase systems and also determines a quality deviation global indicator. In addition, the improvements (implementing an ideal APF) and the assessment (measuring the global deviation) of electric power quality are validated by means of a practical case.