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This paper amis to show the detail of the Standard IEEE 1459-2010 for single phase systems. This Standard aims to quantify the power of electrical systems; however, it does not detail of the deduction of the equations from the circuit diagram. So the contribution of this document is the step-by-step deduction of the equations from the system's voltages and currents. The deduction is made for both linear and non-linear singlephase systems. The detail of the calculation for the active, reactive and apparent power and also the calculation of the power factor and harmonic distortion are presented. [ABSTRACT FROM AUTHOR]

Copyright of Revista Espacios is the property of Talleres de Impresos Oma and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

It is proposed to apply an adaptive hysteresis band that allows to reduce the total harmonic distortion, the ripple and the deformation in the zero crossing of the input current of a bridgeless boost AC-DC converter with power factor correction (PFC). A procedure for calculating the hysteresis band based on the dynamic states of the converter is presented, in such a way that it is possible to keep fixed the switching frequency. The band is applicable to the sliding mode control that allows to improve the dynamic performance of the power converter in the presence of bounded perturbations and significant changes in operating region. The results of the simulation of a 1 kW converter are presented. It is shown that it is possible to raise power factor up to 0.996, to decrease the deformation of the zero crossing and to reduce the total harmonic distortion in the input current down to 2.8%, keeping it below the maximum permissible limits of the standard EN / IEC 61000-3-2 (1000-3- 2). [ABSTRACT FROM AUTHOR]

Copyright of Revista Politécnica is the property of Politechnico Colombian Jaime Isaza Cadavid and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Formación Universitaria is the property of Centro de Informacion Tecnologica (CIT) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper presents multitasking programing of a three-phase speed variator development. This focus has not been reported in technical literature, although it is relevant for engineering power electronics developers, students, and researchers. Hybrid multitasking programing is proposed for the implementation of task that speed variator must carry out. Needed tasks in the speed variator are described and programed in a microcontroller (dsPIC30F4012) using state machines, considering times and priorities with preemptive and cooperative multitasking. This paper proposes a programing form for speed variator that allow software develop since its early stage. The programing structure enables the use of microcontrollers with lower performance. Thus reduction of production costs could be achieved. A three-phase speed variator is presented that can change output-voltage frequency and amplitude without stops or interrupts. Validation of multitasking programming is done on an experimental prototype developed in the laboratory, evaluating the execution times of tasks. [ABSTRACT FROM AUTHOR]

Copyright of Formación Universitaria is the property of Centro de Informacion Tecnologica (CIT) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Formación Universitaria is the property of Centro de Informacion Tecnologica (CIT) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper proposes the control of an AC/DC boost converter with power factor correction using input and output power balance. The operation of the AC/DC converter is presented and the firing sequence of the converter is set is established. As a main contribution, the power balance is presented to obtain the amplitude of the input reference current that allows controlling the DC voltage output. Hysteresis band control for the input current is used, allowing the quick functioning of the control strategy. The proposed hysteresis band control works quickly and allows working in a wide operating range. Experimental results which validate the proposed control are presented. [ABSTRACT FROM AUTHOR]

This study presents the design of a control strategy for alternating current (AC) programmable electronic loads (PEL) applied to test scenarios in power microgrids. The control strategy is based on hysteresis current control (HCC) for the operation of a three-phase inverter to emulate load profiles. The PEL's design is divided into power and control stages to identify operating principles. The topology used is a three-phase four-wire AC PEL, using star and split DC bus connections. The DC link voltage is controlled through a Buck converter based on the power balance of the system. The PEL has been designed to operate in constant power, impedance, and current modes. It is concluded that PEL simulations function properly, representing power stage wavelengths and control signs according to theory. [ABSTRACT FROM AUTHOR]

This paper presents two techniques for identifying topological scenarios of transmission networks for security enhancement in degraded network conditions. The implemented techniques are Simulated Annealing and Iterated Local Search. The objective of the topological modifications is the reduction of the number of violated constraints under N-1 contingencies. The proposed search techniques make topologic explorations through state changes in sub-station switches. These explorations are used to find reconfigurations of the electric power system which guaranty a higher level of security in face of N-1 contingencies when compared with the case when the topology is not changed. Security conditions consider an AC model and a bay-switch model to the assessment of contingencies, which allows the evaluation of real conditions of failure release in the power system. Results are presented with the IEEE 118 bus test system that demonstrates the effectiveness and applicability of the proposed techniques. [ABSTRACT FROM AUTHOR]

This paper proposes a variant of the Colombian official methodology employed in the computation of firm energy (FE) produced by hydro power plants (MCREG). Firm energy is defined as the maximum electrical energy that a plant is able to continuously deliver under low hydrological conditions. This research establishes that for determining the FE, hydrological series should be annually decoupled in the MCREG optimization model to avoid the assumption that future hydrological events will occur in the same historical chronological order. Time series are randomly generated through multivariate and correlated normal distributions, whose parameters are estimated from historical inflow data. Additionally, it is also possible to model the intertemporal correlation between monthly inflows of hydro power plants. The proposed methodology (abbreviated as MDEF) is compared with MCREG. This comparison was done for two power plants (338 and 1000 MW) and the results indicate that EF obtained with MDEF is higher and less uncertain if a significant number of time series is considered. [ABSTRACT FROM AUTHOR]

This paper presents a model for the integrated Transmission and Generation Expansion Planning (TGEP) considering security constraints. The proposed model combines the transmission network expansion (TNE) planning problem with the generation expansion planning (GEP) problem considering security constraints (N- 1 criteria). The resulting problem (TGEP) is approached by means of a mixed integer linear programming model. The main contribution of the paper is the inclusion of security constraints in the TGEP. Results show that including small scale generation in the transmission network expansion planning reduces the number of lines and associated costs incurred in attending the expected demand. Tests were performed with the 6 bus Garver system as well as the IEEE 24 and 48 bus power systems showing the applicability of the proposed model. [ABSTRACT FROM AUTHOR]

This paper presents a comparison of metaheuristics applied to the power system interdiction problem. This problem considers the interaction of a disruptive agent and a system operator. The disruptive agent aims at maximizing the damage of the power system, measured as load shedding. This agent has limited resources and must select the combination of elements to attack that result in the greatest damage to the system, anticipating the reaction of the system operator. On the other hand, the system operator must minimize the load shedding by redispatching generation resources. The interdiction model is nonlinear, nonconvex and multimodal. The solutions provided by three metaheuristic techniques are compared: Genetic Algorithm, GRASP and Iterated Local Search. Results show that the Iterated Local Search adapts better to the type of problem and allows obtaining the best rate between quality of solutions and computation time. [ABSTRACT FROM AUTHOR]

This paper deals with the DC-bus control problem for three-leg four-wires Shunt Active Power Compensators (SAPCs), based on the solution of a mathematical model. Starting with the SAPC concept a mathematical model with enough information to deduce the transfer function that describes the charging/discharging DC-bus process is proposed. A PI controller for tuning the SAPC with enough speed and robustness to keep the DC voltage in an adequate level is employed, so that it is guaranteed that the active power is only supplied on demand. The proposed model guarantees reactive power compensation, regulation of the DC bus and balance between the two capacitors in the DC bus. The mathematical model is verified by Matlab simulations and it is validated through a circuital model implemented in PSIM. [ABSTRACT FROM AUTHOR]

This paper presents a power system interdiction model that incorporates demand response (DR) as strategy to reduce the vulnerability of the system. The interaction of two agents is taken into account: a disruptive agent (terrorist) that pretends causing the maximum load shedding and a protective agent (the system operator) that reacts by modifying the generation dispatch and using DR as an additional strategy to protect the system. The initial hypothesis is that the disruptive agent has limited resources and aims at selecting the set of elements that once attacked would cause the maximum damage to the system. The main contribution of this paper lies in the inclusion of the DR as an additional strategy (besides generation redispatch) to deal with eventual attacks and protect the system. The interaction of the two agents is modeled as a bi-level programming problem and is solved by means of the metaheuristic technique Iterative Local Search. Results on a 24 bus test IEEE system show the effectiveness of DR as a tool to reduce the vulnerability of power systems. [ABSTRACT FROM AUTHOR]

This paper presents a model for the integrated Transmission and Generation Expansion Planning (TGEP). The main contribution of this paper lays in the use of the WTLR indexes (Weighted Transmission Loading Relief) for identifying new expansion candidates (lines and generators). The WTLR indexes are given as function of the distribution power factors and allow measuring the severity of overloads in normal conditions and under contingency (N-1 criterion). The applicability of the proposed model was tested in the IEEE RTS 24 bus power system. The TGEP was solved by means of the NSGA-II (Non-dominated Sorting Genetic Algorithm II) with the aim of minimizing costs and maximizing system security. The inclusion of generators as expansion alternatives reduces the number of necessary transmission lines in the expansion plan, especially when security criteria are taken into account. [ABSTRACT FROM AUTHOR]

This paper presents an optimal budget assignment model for improving quality service in distribution systems. The model consists on a multi objective problem which aims at minimizing maintenance costs in distribution systems while maximizing the reduction of faults rate. This last objective is measured through the SAIFI indicator (System Average Interruption Frequency Index). To solve the proposed model two algorithms were implemented: NSGAII (Non-Dominated Sorting Genetic Algorithm II) and a Memetic Algorithm. Several tests were performed with two real electrical systems of 100 and 200 nodes in the Department of Antioquia in Colombia, showing the applicability of the proposed approach. The optimal Pareto fronts obtained in the problem solution show a set of available options that represent a trade-off between both objectives and provides the system operator with an estimate of how much to invest in maintenance to achieve a desired value of the SAIFI indicator. [ABSTRACT FROM AUTHOR]

This paper presents an analysis of inefficient power flows caused by power converters. Based on the power theory of the IEEE standard 1459 (2010) and starting from the power caused by harmonic currents (DeI), the power DeI_low and DeI_high are proposed for quantifying the inefficient power flows caused by power converters. The power DeI_low is because the existence of low-frequency harmonic currents, while the power DeI_high depends on the number of pulses used in the modulation. An exchange power analysis between the converter, the load, and the semiconductors is presented. There are also included simulation results for a single-phase converter controlled by a Sinusoidal Pulse Width Modulation (SPWM) taking into account the voltage drop in the semiconductors of power switches and changing the number of pulses in the modulation. [ABSTRACT FROM AUTHOR]