A Comprehensive Survey on Different Control Strategies and Applications of Active Power Filters for Power Quality Improvement

This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/).Power quality (PQ) has become an important topic in today’s power system scenario. PQ issues are raised not only in normal three-phase systems but also with the incorporation of different distributed generations (DGs), including renewable energy sources, storage systems, and other systems like diesel generators, fuel cells, etc. The prevalence of these issues comes from the non-linear features and rapid changing of power electronics devices, such as switch-mode converters for adjustable speed drives and diode or thyristor rectifiers. The wide use of these fast switching devices in the utility system leads to an increase in disturbances associated with harmonics and reactive power. The occurrence of PQ disturbances in turn creates several unwanted effects on the utility system. Therefore, many researchers are working on the enhancement of PQ using different custom power devices (CPDs). In this work, the authors highlight the significance of the PQ in the utility network, its effect, and its solution, using different CPDs, such as passive, active, and hybrid filters. Further, the authors point out several compensation strategies, including reference signal generation and gating signal strategies. In addition, this paper also presents the role of the active power filter (APF) in different DG systems. Some technical and economic considerations and future developments are also discussed in this literature. For easy reference, a volume of journals of more than 140 publications on this particular subject is reported. The effectiveness of this research work will boost researchers’ ability to select proper control methodology and compensation strategy for various applications of APFs for improving PQ.publishedVersio

Optimal Designing Grid-Connected PV Systems

Photovoltaic systems, direct conversion of solar energy to electrical energy, are produced in the form of DC power by photovoltaic arrays bathed in sunlight and converted into AC power through an inverter system, which is more convenient to use. There are two main paradigms for optimal designing of photovoltaic systems. First, the system can be designed such that the generated power and the loads, that is, the consumed power, match. A second way to design a photovoltaic system is to base the design on economics, as pinpointed in the following. Photovoltaic grid connected through shunt active filter by considering maximum power point tracking for these systems is known as the optimal design. This chapter is organized as follows: First, we discuss an overview of grid-connected photovoltaic systems. After that, we take a more detailed look on grid-connected photovoltaic system via active filter; in this section, we explain the modeling of photovoltaic panel and shunt active filter. In the next section, we learn different maximum power point tracking methods and also learn how to design DC link as a common bus of shunt active filter and photovoltaic system. Finally, MATLAB/Simulink simulations verify the performance of the proposed model performance

MPPT Schemes for PV System Under Normal and Partial Shading Condition: a Review

The photovoltaic system is one of the renewable energy device, which directly converts solar radiation into electricity. The I-V characteristics of PV system are nonlinear in nature and under variable Irradiance and temperature, PV system has a single operating point where the power output is maximum, known as Maximum Power Point (MPP) and the point varies on changes in atmospheric conditions and electrical load. Maximum Power Point Tracker (MPPT) is used to track MPP of solar PV system for maximum efficiency operation. The various MPPT techniques together with implementation are reported in literature. In order to choose the best technique based upon the requirements, comprehensive and comparative study should be available. The aim of this paper is to present a comprehensive review of various MPPT techniques for uniform insolation and partial shading conditions. Furthermore, the comparison of practically accepted and widely used techniques has been made based on features, such as control strategy, type of circuitry, number of control variables and cost. This review work provides a quick analysis and design help for PV systems. Article History: Received March 14, 2016; Received in revised form June 26th 2016; Accepted July 1st 2016; Available online How to Cite This Article: Sameeullah, M. and Swarup, A. (2016). MPPT Schemes for PV System under Normal and Partial Shading Condition: A Review. Int. Journal of Renewable Energy Development, 5(2), 79-94. http://dx.doi.org/10.14710/ijred.5.2.79-9

DSTATCOM with Improved LMS based IRP theory

In this paper, grid connected DSTATCOM with three phase three wire has been proposed for harmonics elimination, reactive power compensation and active power injection into the grid. An improved instantaneous reactive power theory based on the least mean square is computed. The least mean square (LMS) algorithm is combined with instantaneous reactive power theory (IRPT) to improve its dynamics performance and eliminates the use of low pass filter requirement for computation of reference current. The harmonics component of the active power is estimated from LMS algorithm generated load harmonics currents. The performance characteristic of DSTATCOM is estimated with control scheme using computer simulation. The technique is based on the instantaneous transformation of instantaneous signals and taking advantage of the subsequent calculation of power from supply side to the loads. The neural network based method to estimate the harmonic online, DSTATCOM can compensate the harmonics. The computer simulation is carried out with MATLAB Simulink power system block sets

ANALOG SIGNAL PROCESSING SOLUTIONS AND DESIGN OF MEMRISTOR-CMOS ANALOG CO-PROCESSOR FOR ACCELERATION OF HIGH-PERFORMANCE COMPUTING APPLICATIONS

Emerging applications in the field of machine vision, deep learning and scientific simulation require high computational speed and are run on platforms that are size, weight and power constrained. With the transistor scaling coming to an end, existing digital hardware architectures will not be able to meet these ever-increasing demands. Analog computation with its rich set of primitives and inherent parallel architecture can be faster, more efficient and compact for some of these applications. The major contribution of this work is to show that analog processing can be a viable solution to this problem. This is demonstrated in the three parts of the dissertation. In the first part of the dissertation, we demonstrate that analog processing can be used to solve the problem of stereo correspondence. Novel modifications to the algorithms are proposed which improves the computational speed and makes them efficiently implementable in analog hardware. The analog domain implementation provides further speedup in computation and has lower power consumption than a digital implementation. In the second part of the dissertation, a prototype of an analog processor was developed using commercially available off-the-shelf components. The focus was on providing experimental results that demonstrate functionality and to show that the performance of the prototype for low-level and mid-level image processing tasks is equivalent to a digital implementation. To demonstrate improvement in speed and power consumption, an integrated circuit design of the analog processor was proposed, and it was shown that such an analog processor would be faster than state-of-the-art digital and other analog processors. In the third part of the dissertation, a memristor-CMOS analog co-processor that can perform floating point vector matrix multiplication (VMM) is proposed. VMM computation underlies some of the major applications. To demonstrate the working of the analog co-processor at a system level, a new tool called PSpice Systems Option is used. It is shown that the analog co-processor has a superior performance when compared to the projected performances of digital and analog processors. Using the new tool, various application simulations for image processing and solution to partial differential equations are performed on the co-processor model

Análise comparativa do desempenho das manobras de religamento monopolar e tripolar para eliminação de faltas monofásicas em linhas de transmissão

Orientador: Maria Cristina Dias TavaresDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Elétrica e de ComputaçãoResumo: Um sistema de energia elétrica compreende geração, transmissão e distribuição de energia elétrica. As linhas de transmissão são usadas para transmitir energia elétrica a centros de carga distantes. O rápido crescimento dos sistemas de energia elétrica nas últimas décadas resultou em um grande aumento do número de linhas em operação e seu comprimento total. Para níveis de transmissão EHV (extra alta tensão), entre 90-95% de todas as falhas de linha envolvem apenas uma única fase. Destes, mais de 90% são temporários e podem ser compensados ??por três fases de religamento; Conseqüentemente, faltas fase-terra têm recebido a maior atenção em estudos de sistema. Este projeto analisa as entidades da linha de transmissão resultantes da eliminação de uma falta monofásica usando o SPAR (Auto-Reclusão Monofásica) e o religamento automático trifásico na linha de transmissão de 400 kV. O projeto analisa a influência de diferentes parâmetros do sistema, como nível de compensação, comprimento da linha e local da falta, juntamente com o método de mitigação. Para o estudo de simulação, PSCAD / EMTDC é selecionado como o software de simulaçãoAbstract: An electric power system comprises of generation, transmission and distribution of electric energy. Transmission lines are used to transmit electric power to distant large load centers. The rapid growth of electric power systems over the past few decades has resulted in a large increase of the number of lines in operation and their total length. For EHV (extra high voltage) transmission levels, between 90¿95% of all line faults involve only a single phase. Of these, more than 90% are temporary and can be cleared by three phase reclosing; consequently, phase-to-ground faults have received the most attention in system studies. This project analyzes the transmission line entities resulting from elimination of a single-phase fault by using the SPAR (Single-Phase Auto-Reclosing) and three-phase auto-reclosing on the 400 kV transmission line. The project analyzes the influence of different system parameters like compensation level, line length and fault location together with the mitigation method. For the simulation study, PSCAD/EMTDC is selected as the simulation softwareMestradoEnergia EletricaMestre em Engenharia ElétricaCAPE

The assesement of the shunt active filter efficiency under varied power supply source and load parameters

The results of theoretical and experimental studies on the problems of effective application of shunt active filters for power quality improvement and electromagnetic compatibility ensuring were presented in this article. Based on the different theories and methods, the most effective and well-studied control algorithms of shunt active filters were determined and analyzed to ensure their effective application in distributed generation systems and combined power supply systems. Mathematical and computer simulation models of shunt active filters with different control algorithms in distributed generation systems and combined power supply systems were developed. According to the results of mathematical modeling and computer simulation, the dependences were detected, reflecting the influences of internal and external parameters on the factors, determining the efficiency of the correction of power quality indicators. The range of permissible changes in the parameters of shunt active filters by saving the required efficiency level of power quality correction was detected under varied power supply system characteristics, load parameters and also in hybrid structures. The adaptive algorithm of the shunt active filter functioning under varied application conditions for automated power quality improvement is developed on the basi