A study of UPQC: emerging mitigation techniques for the impact of recent power quality issues

Circuit World ◽  
2020 ◽  
Vol 47 (1) ◽  
pp. 11-21
Author(s):  
Ananthan Nagarajan ◽  
Sivachandran P. ◽  
Suganyadevi M.V. ◽  
Muthukumar P.
Keyword(s):  
Power Quality ◽  
Content Type ◽  
Facts Devices ◽  
Recent Developments ◽  
Quality Issues ◽  
Power Quality Conditioner ◽  
Compensating Devices ◽  
Quality Of Electric Power ◽  
The Impact

Purpose 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. Design/methodology/approach The work carried out in the Facts device and power quality issues. Findings 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. Originality/value 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

scholarly journals Fault Clearance in Nine-Bus system using Custom Power Devices

2020 ◽  
Vol 9 (2) ◽  
pp. 1756-1762 ◽  
Keyword(s):  
Power System ◽  
Power Quality ◽  
Reactive Power ◽  
Vital Role ◽  
Machine System ◽  
Facts Devices ◽  
Three Phase ◽  
Compensating Devices ◽  
Fault Clearance

The power transfer capability of a system determines the power quality and the reliability of the power system. The transmission side of the power system is of different configuration. This paper involves the modeling of a three-phase multi-machine system with nine bus configurations. The system is subjected to different fault conditions. The system is modeled with the help of MATLAB- Simulink. The power quality of the system is analyzed. The system active and the reactive power can be compensated by the FACTS devices. The FACTS devices are power compensating devices that play a vital role in increasing the power quality of the system. The three-phase multi-machine system is integrated with the FACTS devices like STATCOM and UPFC and different parameters where analyzed

Distributed Generation Inverter as APF in Dual APF DG interfacing Scheme

2017 ◽  
Vol 8 (3) ◽  
pp. 1441
Author(s):  
Yadiki Rajendra Babu ◽  
C. Srinivasa Rao
Keyword(s):  
Power Quality ◽  
Distributed Generation ◽  
Active Power ◽  
Harmonic Compensation ◽  
Active Power Filters ◽  
Power Filters ◽  
Electrical Engineers ◽  
Quality Issues ◽  
Compensating Devices

<span>Power quality issues are the most concerned area for electrical engineers in these modern days due to indusrtrialization and advancements in electronics. Harmonics are one of the power quality issues that deteriorated the quality of source components delivered to load. Active power filters (APF) are the compensating devices used to mitigate harmonics. Distributed generation (DG) became a trendline due to economical, technical and environmental reasons. This paper presents the harmonic compensation using dual APF sharing compensating signals while active power is fed from distributed generation to grid. DG inverter acts as an interface between DG system and grid to feed active power from DG to grid. In this context, the DG inverter acts both as inverter and APF, used as inverter to invert supply from DG and feeds grid for specified time and also as APF for harmonic compensation thereafter along with dual APF. The proposed system is developed and results are obtained using MATLAB/SIMULINK software. Results are shown for DG inverter feeding active power to grid and also acting as APF. Dual APF characteristics are also shown.  </span>

Adaptive whale optimization for intelligent multi-constraints power quality improvement under deregulated environment

2019 ◽  
Vol 17 (3) ◽  
pp. 490-514
Author(s):  
Niharika Thakur ◽  
Y.K. Awasthi ◽  
Manisha Hooda ◽  
Anwar Shahzad Siddiqui
Keyword(s):  
Power Quality ◽  
Optimization Algorithm ◽  
Whale Optimization Algorithm ◽  
Quality Improvements ◽  
Content Type ◽  
Facts Devices ◽  
Whale Optimization ◽  
Quality Issues ◽  
Better Than ◽  
Bus System

Purpose 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. Design/methodology/approach 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. Findings 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. Originality/value 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.

scholarly journals Performance Unified Power Quality Conditioner using Instantaneous Reactive Power Theory

2019 ◽  
Vol 9 (1) ◽  
pp. 7537-7540
Keyword(s):  
Power Quality ◽  
Reactive Power ◽  
Focal Point ◽  
Harmonic Distortion ◽  
Modern Technology ◽  
High Quality ◽  
Unified Power Quality Conditioner ◽  
Power Quality Conditioner ◽  
The Impact

The development use power digital tools presents harmonics in the supply system which develops an issue in the high quality of power supplied. Great Power Quality is quite crucial for our everyday use home appliances in both commercial as well as residential fields. Scientists have actually attempted as well as applied several valuable innovation for eliminating all the voltage and also present relevant harmonic incident troubles which consequently enhances the high quality of power provided to the power system. The focal point of this thesis is the execution of control methods like SRF concept as well as immediate power for the procedure of Unified Power Quality Conditioner (UPQC) which is just one of the current modern technology that consists of both collection and also shunt energetic power filter operating at the very same time as well as thus boosts all the present as well as voltage relevant trouble like voltage sag/swell, flicker, and so on at the exact same time and also assists in decrease of Total Harmonic Distortion. Harmonic materials of the resource current has actually been determined as well as contrasted for the various situations to show the impact of harmonic removal circuit on the harmonic settlement quality of AC-DC power supply feeding to nonlinear tons. Simulation results gotten programs that the efficiency of compensator is located to be far better than without compensator.

Do disclosure and transparency affect bank’s financial performance?

2019 ◽  
Vol 19 (6) ◽  
pp. 1344-1361
Author(s):  
Isaiah Oino
Keyword(s):  
Risk Management ◽  
Corporate Governance ◽  
Financial Performance ◽  
Financial Institutions ◽  
Content Type ◽  
Loan Portfolios ◽  
Cent Level ◽  
Transparency And Disclosure ◽  
The Impact

Purpose The purpose of this paper is to examine the impact of transparency and disclosure on the financial performance of financial institutions. The emphasis is on assessing transparency and disclosure; auditing and compliance; risk management as indicators of corporate governance; and understanding how these parameters affect bank profitability, liquidity and the quality of loan portfolios. Design/methodology/approach A sample of 20 financial institutions was selected, with ten respondents from each, yielding a total sample size of 200. Principal component analysis (PCA), with inbuilt ability to check for composite reliability, was used to obtain composite indices for the corporate governance indicators as well as the indicators of financial performance, based on a set of questions framed for each institution. Findings The analysis demonstrates that greater disclosure and transparency, improved auditing and compliance and better risk management positively affect the financial performance of financial institutions. In terms of significance, the results show that as the level of disclosure and transparency in managerial affairs increases, the performance of financial institutions – as measured in terms of the quality of loan portfolios, liquidity and profitability – increases by 0.3046, with the effect being statistically significant at the 1 per cent level. Furthermore, as the level of auditing and the degree of compliance with banking regulations increases, the financial performance of banks improves by 0.3309. Research limitations/implications This paper did not consider time series because corporate governance does not change periodically. Practical implications This paper demonstrates the importance of disclosure and transparency in managerial affairs because the performance of financial institutions, as measured in terms of loan portfolios, liquidity and profitability, increases by 0.4 when transparency and disclosure improve, with this effect being statistically significant at the 1 per cent level. Originality/value The use of primary data in assessing the impact of corporate governance on financial performance, instead of secondary data, is the primary novelty of this study. Moreover, PCA is used to assess the weight of the various parameters.

scholarly journals Knowledge sharing in open source software communities: motivations and management

2015 ◽  
Vol 19 (4) ◽  
pp. 791-813 ◽  
Author(s):  
Zilia Iskoujina ◽  
Joanne Roberts
Keyword(s):  
Knowledge Sharing ◽  
Open Source ◽  
Open Source Software ◽  
Online Communities ◽  
Descriptive Analysis ◽  
Online Questionnaire ◽  
Content Type ◽  
The Individual ◽  
The Impact

Purpose – This paper aims to add to the understanding of knowledge sharing in online communities through an investigation of the relationship between individual participant’s motivations and management in open source software (OSS) communities. Drawing on a review of literature concerning knowledge sharing in organisations, the factors that motivate participants to share their knowledge in OSS communities, and the management of such communities, it is hypothesised that the quality of management influences the extent to which the motivations of members actually result in knowledge sharing. Design/methodology/approach – To test the hypothesis, quantitative data were collected through an online questionnaire survey of OSS web developers with the aim of gathering respondents’ opinions concerning knowledge sharing, motivations to share knowledge and satisfaction with the management of OSS projects. Factor analysis, descriptive analysis, correlation analysis and regression analysis were used to explore the survey data. Findings – The analysis of the data reveals that the individual participant’s satisfaction with the management of an OSS project is an important factor influencing the extent of their personal contribution to a community. Originality/value – Little attention has been devoted to understanding the impact of management in OSS communities. Focused on OSS developers specialising in web development, the findings of this paper offer an important original contribution to understanding the connections between individual members’ satisfaction with management and their motivations to contribute to an OSS project. The findings reveal that motivations to share knowledge in online communities are influenced by the quality of management. Consequently, the findings suggest that appropriate management can enhance knowledge sharing in OSS projects and online communities, and organisations more generally.

Shareholder risk-taking incentives in the presence of contingent capital

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Mahmoud Fatouh ◽  
Ayowande A. McCunn
Keyword(s):  
Risk Taking ◽  
Banking System ◽  
Capital Requirements ◽  
Content Type ◽  
Basic Model ◽  
Conversion Rates ◽  
A Minor ◽  
The Impact ◽  
Practical Implications

Purpose This paper aims to present a model of shareholders’ willingness to exert effort to reduce the likelihood of bank distress and the implications of the presence of contingent convertible (CoCo) bonds in the liabilities structure of a bank. Design/methodology/approach This study presents a basic model about the moral hazard surrounding shareholders willingness to exert effort that increases the likelihood of a bank’s success. This study uses a one-shot game and so do not capture the effects of repeated interactions. Findings Consistent with the existing literature, this study shows that the direction of the wealth transfer at the conversion of CoCo bonds determines their impact on shareholder risk-taking incentives. This study also finds that “anytime” CoCos (CoCo bonds trigger-able anytime at the discretion of managers) have a minor advantage over regular CoCo bonds, and that quality of capital requirements can reduce the risk-taking incentives of shareholders. Practical implications This study argues that shareholders can also use manager-specific CoCo bonds to reduce the riskiness of the bank activities. The issuance of such bonds can increase the resilience of individual banks and the whole banking system. Regulators can use restrictions on conversion rates and/or requirements on the quality of capital to address the impact of CoCo bonds issuance on risk-taking incentives. Originality/value To model the risk-taking incentives, authors generally modify the asset processes to introduce components that reflect asymmetric information between CoCo holders and shareholders and/or managers. This paper follows a simpler method similar to that of Holmström and Tirole (1998).

Impact of embodiment on attitude strength

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Sunaina Shrivastava ◽  
Gaurav Jain ◽  
JaeHwan Kwon ◽  
Dhananjay Nayakankuppam
Keyword(s):  
Undergraduate Students ◽  
Cognitive Process ◽  
Target Object ◽  
Attitude Strength ◽  
Quality Of Information ◽  
Content Type ◽  
Lab Experiments ◽  
Attitude Accessibility ◽  
The Impact

Purpose Traditionally, it has been held that strong attitudes are a result of the conscious cognitive process of elaboration where one engages in effortful issue-relevant thinking. The purpose of this study is to show that attitude strength can follow from processes not just limited to elaboration – as a function of certain embodied states. This study examines bodily manipulations that could alter perceptions about the quality of the information describing a target (e.g. notion of “hard/soft” evidence), and, find that such an embodiment leads one to have strong attitudes toward the target object. This study proposes an attitude-rehearsal-based mechanism to explain the phenomenon. Design/methodology/approach This study have relied on lab experiments as a methodology – undergraduate students and American residents served as participants. This study have conducted a pre-registered study as well. Findings In the work, the study shows that strong attitudes can result from processes not just limited to elaboration, as a function of certain embodied states. This paper examines bodily manipulations that could alter perceptions about the quality of information describing the target (e.g. notion of “hard vs soft”; “converging vs diverging” information), and, find that such an embodiment leads one to have strong attitudes toward the target. This study consistently observed that the bodily manipulations influence attitude accessibility, a direct and operational indicator of attitude strength. This study further validates an attitude-rehearsal-based mechanism to explain the observed phenomenon. Originality/value While much work has investigated the impact of embodiment on attitudes, little attention has been paid to whether, and, how embodied states can impact the “strength” of the attitude without impacting the attitude itself – to the knowledge, this paper is the first to document this. Moreover, traditionally, it has been held that strong attitudes are a result of the conscious cognitive process of elaboration where one engages in effortful issue-relevant thinking. This study however shows that attitude strength can follow from processes not just limited to elaboration – as a function of certain embodied states.

The model of HRM-trust-commitment relationships

2015 ◽  
Vol 115 (8) ◽  
pp. 1457-1480 ◽  
Author(s):  
Dagmara Lewicka ◽  
Katarzyna Krot
Keyword(s):  
Structural Equation ◽  
Affective Commitment ◽  
Content Type ◽  
Calculative Commitment ◽  
Starting Point ◽  
Research Findings ◽  
Organisational Trust ◽  
The Impact ◽  
The Relationship

Purpose – It is worth focusing on the examination of factors influencing the quality of the work environment. The purpose of this paper is to verify the influence of the HRM system and organisational trust on employee commitment. Design/methodology/approach – The survey was conducted in Poland among 370 employees in organisations from two sectors of the economy: services and industry. The verification of the theoretical model was performed based on structural equation modelling. Findings – Research findings made it possible to successfully verify the model of the relationship between the HRM system (practices, process), organisational trust and commitment. The starting point for trust in an organisation followed by commitment is the HRM system. It seems that the impact of the HRM process on creating organisational trust is higher. Research findings have also confirmed a relationship between each type of organisational trust and calculative commitment based on benefits, which is a strong determinant of affective commitment. Organisational trust is, therefore, an intermediary factor because the organisation must build trust in employees first before they become affectively committed. Originality/value – Current studies have not examined the issue of a mutual relationship between three constructs: perceived HRM practices and process, organisational trust and commitment. What is more, previous research was confined to the constructs analysed holistically without considering their complexity (different types of trust and commitment). In addition, the authors attempted to enrich Allen and Mayer’s (1991) model with a new aspect of the commitment – calculative, which is linked to the benefits received by employees. The authors also identified the mediating influence of the trust and calculative commitment onto the affective commitment.

scholarly journals An Adaptive Bitrate Switching Algorithm for Speech Applications in Context of WebRTC

2021 ◽  
Vol 17 (4) ◽  
pp. 1-21
Author(s):  
Mohannad Alahmadi ◽  
Peter Pocta ◽  
Hugh Melvin
Keyword(s):  
Real Time ◽  
Data Exchange ◽  
Quality Of Experience ◽  
End User ◽  
High Quality ◽  
Content Type ◽  
Switching Algorithm ◽  
Wide Range ◽  
The Impact

Web Real-Time Communication (WebRTC) combines a set of standards and technologies to enable high-quality audio, video, and auxiliary data exchange in web browsers and mobile applications. It enables peer-to-peer multimedia sessions over IP networks without the need for additional plugins. The Opus codec, which is deployed as the default audio codec for speech and music streaming in WebRTC, supports a wide range of bitrates. This range of bitrates covers narrowband, wideband, and super-wideband up to fullband bandwidths. Users of IP-based telephony always demand high-quality audio. In addition to users’ expectation, their emotional state, content type, and many other psychological factors; network quality of service; and distortions introduced at the end terminals could determine their quality of experience. To measure the quality experienced by the end user for voice transmission service, the E-model standardized in the ITU-T Rec. G.107 (a narrowband version), ITU-T Rec. G.107.1 (a wideband version), and the most recent ITU-T Rec. G.107.2 extension for the super-wideband E-model can be used. In this work, we present a quality of experience model built on the E-model to measure the impact of coding and packet loss to assess the quality perceived by the end user in WebRTC speech applications. Based on the computed Mean Opinion Score, a real-time adaptive codec parameter switching mechanism is used to switch to the most optimum codec bitrate under the present network conditions. We present the evaluation results to show the effectiveness of the proposed approach when compared with the default codec configuration in WebRTC.

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