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The purpose of this study is to help the researchers, public, industries and government to realize the tremendous trends to improve the power quality of both sources and load side.

The work carried out in the Facts device and power quality issues.

Maintaining the quality of electric power is always a challenging task. The effect of power electronics devices leads to improper power quality. The use of FACTS devices is preferably the best approach to treat power-quality-related problems. Usually, all FACTS devices are constructed to operate on the side of either the source side or the load.

This paper explores a broad comprehensive study of various types of power quality problems and classification of FACTS devices with its recent developments. Furthermore unified power quality conditioner (UPQC) is particularly reviewed to highlight the advantages over other compensating devices. An exhaustive study of literature has been carried out and most significant concepts are presented

The purpose of this paper is to address the issue of power quality through a case study in an IT‐intensive modern office building.

This paper presents results from a power quality audit conducted last year. Firstly, the power site inspection included: (a) a walk‐down of the facility's electrical system to inspect the condition of equipment and becoming familiar with the electrical system; (b) interviewing facility electrical personnel and end‐users on failure of equipment; (c) identifying and collecting the electronic equipment that is most sensitive to power disturbances; (d) requesting and reviewing equipment literature and electromagnetic compatibility characteristics; (e) after that, in the power quality monitoring, voltage and current were measured at various floors.

It was found that the main problems for the equipment installed were harmonics and leakage currents. The paper examines the causes and effects of power disturbances that affect computer or any other microprocessor based equipment and analyses the disadvantages of modern power supplies.

This provides useful information for facilities managers on the current state of power disturbances. The convenience of “enhanced power supply” is also discussed. Finally, it is addressed the role of standards on the protection of IT and the implications for the final costumer.

This paper has provided empirical data from a power site survey developed in a high tech building. This case study demonstrates the impacts of generalized electronic devices on the power quality of the buildings and the implications on energy uses.

Power quality issues highly affect the secure and economic operations of the power system. Although numerous methodologies are reported in the literature, flexible alternating current transmission system (FACTS) devices play a primary role. However, the FACTS devices require optimal location and sizing to perform the power quality enhancement effectively and in a cost efficient manner. This paper aims to attain the maximum power quality improvements in IEEE 30 and IEEE 57 test bus systems.

This paper contributes the adaptive whale optimization algorithm (AWOA) algorithm to solve the power quality issues under deregulated sector, which enhances available transfer capability, maintains voltage stability, minimizes loss and mitigates congestions.

Through the performance analysis, the convergence of the final fitness of AWOA algorithm is 5 per cent better than artificial bee colony (ABC), 3.79 per cent better than genetic algorithm (GA), 2,081 per cent better than particle swarm optimization (PSO) and fire fly (FF) and 2.56 per cent better than whale optimization algorithm (WOA) algorithms at 400 per cent load condition for IEEE 30 test bus system, and the fitness convergence of AWOA algorithm for IEEE 57 test bus system is 4.44, 4.86, 5.49, 7.52 and 9.66 per cent better than FF, ABC, WOA, PSO and GA, respectively.

This paper presents a technique for minimizing the power quality problems using AWOA algorithm. This is the first work to use WOA-based optimization for the power quality improvements.

The purpose of this paper is to develop a new model – namely service quality enhancement – in the electricity utility sector of south India and to test this model's fitness.

Effective customer satisfaction investigation is a very important precondition for a power supply enterprise to win in the market competition. The problems that need to be solved for the power supply enterprise are how to use advanced and practiced methods to evaluate electricity customer satisfaction, and how to use results of the evaluation to improve their service. Planning and operating modern electric power systems involves several interlinked and complex tasks. In this paper, structural equation modeling (SEM) is applied to the electricity utility service model to verify service quality satisfaction. To determine the scope of the electricity industry and its relationship with overall service quality, a questionnaire-based survey was conducted and a standard questionnaire was designed for all customers in different groups of stakeholders (i.e. domestic, industrial, agricultural, public organization). To investigate the respondents’ perceptions regarding the service quality of the electricity utility industry, 200 questionnaires were sent, and from these 169 responses were collected, consisting of 53 responses from the domestic sector, 43 industrial, 30 agricultural, and the remaining 43 from public organization consumers. Then a model was constructed using SEM and tested by Amos 18 to verify the casual relationship between the measured dimensions and the electricity service quality.

The results indicate that electricity service has a direct relationship with the dimensions of reliability, tangibility, empathy responsiveness, assurance, security and stability.

In this era electricity is the vital need, but due to regular interruptions in the electricity service, customer dissatisfaction is the measured issue. At the current time, the Indian electricity utility sector enjoys a monopolistic business. Therefore, there is hardly any effort to improve the service quality in this sector due to a lack of administrative pressure and reformation measures. Indian electricity consumers face many quality-related problems as far as the distribution of electricity is concerned. In order to assess service quality in electricity distribution, a survey has been conducted in this work to extract quality constructs from a customer's perspective. One of the contributions of this work is that on the basis of results obtained from factor analysis of the survey data, an instrument has been proposed for the first time in the Indian context, consisting of seven dimensions (reliability, tangibility, empathy, responsiveness, assurance, security and stability). This instrument would help to measure the service quality of the Indian electricity utility sectors, and it provides insights for managers and administrators to set a service standard to fill the service gap. SEM is a tool is used for confirmatory and exploratory factor analysis. It is used to test and validate standard instruments. Through confirmatory and exploratory factor analysis using SEM, the proposed service quality model has been tested and validated for practical acceptance in Indian electricity industry.

The earlier methods are more resilient to improvements such as load shift and path change. This results in problems such as a voltage drop and a high reactive flux. In addition, due to the delay, congestion or interruption of the transmission, the system cannot receive all phasor measurement unit (PMU) measurements at the relevant time as well as the presence of noise in the received data.

With the development of wide area measurement system technologies, it seems to be possible to track voltage stability online via time-stamped PMUs. As the voltage instability causes a voltage decomposition, voltage instability is one of the most important problems when monitoring the power supply.

This harmonic distortion significantly decreases the data quality in the grid. As a result, instability ascertainment based on PMU has been suggested as a method for detecting voltage instability in power systems monitored with PMU. In addition, a technique called instability amendment via load dropping has been proposed to keep the device from collapsing due to voltage failure.

To improve the power output, the power prominence melioration technique was developed. This proposed system has been implemented in MATLAB Simulink and compared with the recent researches.

The assessment of the quality of the electric power supply, as well as that of the electric loads, is becoming a critical problem, especially when the liberalization of the electricity market is involved. Power quality can be evaluated by means of a number of quantities and indices whose measurement is not straightforward and is generally attained by means of digital signal processing techniques based on complex algorithms. The assessment of the uncertainty of the results of such measurements is a critical, open problem. This paper proposes a general purpose approach, based on the Monte Carlo method that, starting from the estimated contributions to the uncertainty of each device in the measurement chain, estimates the probability density distribution of the measurement result, and therefore, its standard uncertainty. This approach has been experimentally validated for the active power measurement and applied to the estimation of the uncertainty of the measurement of more complex power quality indices.

These implementations not only generate excessive voltage levels to enhance the quality of power but also include a detailed investigating of the various modulation methods and control schemes for multilevel inverter (MLI) topologies. Reduced harmonic modulation technology is used to produce 11-level output voltage with the production of renewable energy applications. The simulation is done in the MATLAB/Simulink for 11-level symmetric MLI and is correlated with the conventional inverter design.

This paper is focused on investigating the different types of asymmetric, symmetric and hybrid topologies and control methods used for the modular multilevel inverter (MMI) operation. Classical MLI configurations are affected by performance issues such as poor power quality, uneconomic structure and low efficiency.

The variations in both carrier and reference signals and their performance are analyzed for the proposed inverter topologies. The simulation result compares unipolar and bipolar pulse-width modulation (PWM) techniques with total harmonic distortion (THD) results. The solar-fed 11-level MMI is controlled using various modulation strategies, which are connected to marine emergency lighting loads. Various modulation techniques are used to control the solar-fed 11-level MMI, which is connected to marine emergency lighting loads. The entire hardware system is controlled by using SPARTAN 3A field programmable gate array (FPGA) board and the least harmonics are obtained by improving the power quality.

The simulation result compares unipolar and bipolar PWM techniques with THD results. Various modulation techniques are used to control the solar-fed 11-level MMI, which is connected to marine emergency lighting loads. The entire hardware system is controlled by a SPARTAN 3A field programmable gate array (FPGA) board, and the power quality is improved to achieve the lowest harmonics possible.

An electrical power system is expected to deliver undistorted sinusoidal, rated voltage and current continuously to the end-users. The problem of power quality (PQ) occurs when there is (are) deviation(s) in voltage and/or current which cause(s) failure or mal-operation of the customer's equipments. Various methods are suggested to detect and classify single PQ event in a power system, the performance of such methods to classify composite PQ events is limited. The purpose of this paper is the classification of composite PQ events in emerging power systems.

This paper proposes an effective method to classify composite PQ events using Hilbert Huang transform (HHT). The performance of probabilistic neural network (PNN) classifier and support vector machine (SVM) classifier to efficiently classify composite PQ events is compared.

The features extracted from HHT are simple yet effective. SVMs and PNN classifiers are used for PQ classification. It is found that PNN classifier outperforms SVM with the classification accuracy of 100 percent.

Different PQ signals used for analysis are generated by simulating a practical distribution system of an Indian academic institution.

This paper aims to propose an improved multifunctional control strategy for achieving real, reactive power flow control and the mitigation of power quality issues in grid integrated photovoltaic (GIPV) systems.

The paper proposes a dual stage, three phase, multifunctional GIPV system with modified instantaneous reactive power (IRP) theory-based and modified synchronous reference frame (SRF) theory-based control algorithms for reference template generation with continuous load power requirement tracking. The control structure is designed so as to impart virtual distribution static compensator functionality to the photovoltaic inverter. The dual mode operation in active filter and renewable power injection modes provides enhanced capability to the GIPV system. A comprehensive evaluation of the dynamic behaviour of the GIPV system is carried out for various conditions of irradiance and load under MATLAB/Simulink platform. The performance comparison is done considering an uncompensated system and the GIPV system with both proposed control algorithms.

The extensive simulation results demonstrate that the proposed modified SRF theory-based multifunctional control strategy shows superior performance in real and reactive power flow control; reduction in real and reactive burden of the utility grid; and regulation of dc bus voltage under varying scenarios of irradiance and load. Furthermore, there is improvement of grid power factor and reduction in total harmonic distortion of grid currents in compliance with the IEEE 519 standard even with highly non-linear loads at the point of common coupling.

The proposed modified SRF theory-based multifunctional controller offers a viable solution for power quality enhancement as well as the realization of effective real and reactive power flow control in GIPV systems. Thus, the penetration level of distributed generation can be increased in this era of global energy crisis.

This paper aims to reduce the impact of disordered charging of large-scale electric vehicles (EVs) on the grid. EV is great significance for environmental protection, energy conservation and emission reduction to replace fuel vehicles with EVs. However, as a kind of random mobile load, large-scale integration into the power grid may lead to power quality problems such as line overload, line loss increase and voltage reduction. This paper realizes the orderly charging of electric vehicles and the safe operation of the distribution network by optimizing the dispatching scheme.

This paper takes the typical IEEE-33 node distribution system as the research object, adopts the improved particle swarm optimization algorithm and takes the minimum operation cost, the minimum environmental pollution, the minimum standard deviation of daily load, the minimum peak valley difference of load, the minimum node voltage offset rate and the minimum system grid loss rate as the optimization objectives.

Controlling the disordered charging of large-scale electric vehicles by optimizing the dispatching algorithm can realize the full consumption of renewable energy and the safe operation of the power grid.

Results show that the proposed scheme can realize the transfer of charging load in time and space, so as to stabilize the load fluctuation of distribution grid, improve the operation quality of power grid, reduce the charging cost of users and achieve the expected research objectives.