Line-start synchronous machines (LSSMs) emerged as an efficient alternative for induction machines in numerous constant speed applications. This study reviewed evolution, technological advancements, design concepts, optimisation techniques, and possible applications in a comprehensive manner. A case study on the reviewed LSSM has been carried out based on its suitability in agricultural applications in India. Further, the performance comparison and significant advantages between the existing induction machine and LSSM are finally discussed.

https://ietresearch.onlinelibrary.wiley.com/doi/pdf/10.1049/iet-epa.2018.5283

Review on the evolution of technology advancements and applications of line-start synchronous machines

Humidification plant in a textile industry is one of the major power consumers due to its continuous operation for maintaining required Relative Humidity (RH) and temperature of spinning plant to increase the quality of yarn The traditional method of operation of induction motors in humidification plant was effective, but not energy efficient To overcome this problem, the emerging trend is the widespread adoption of variable frequency drives (VFD) which can offer potential energy savings in a system by allowing continuous process of speed control In this paper, modeling, simulation and performance analysis of ‘Open loop and closed loop speed control of induction motor using Variable frequency drive’ in MATLAB/Simulink and the Performance Verification of humidification plant in a textile industry where VFDs are installed very recently are presented

Energy conservation using variable frequency drives of a humidification plant in a textile mill

Public and private sectors are concerned with controlling the undesirable environmental impact of the new construction and the renovation of buildings. The building industry accounts for 32% of global energy consumption, 19% of energy-related CO₂ emissions, 25% of global water, and 40% of global resources depletion. The operational and maintenance phase of buildings accounts for 70% to 90% of the overall impact on environment. The literature review revealed many rating systems that were developed during the last few decades to assess the sustainability of buildings based on economic, social and environmental criteria. However, they represented local industries and none of them proposed a tool to select the best economic rehabilitation alternatives to upgrade building sustainability. Therefore, the main goal of this research is to establish an integrated sustainability rating and rehabilitation selection tool for buildings to fulfil the following objectives: 1) identify and study sustainability assessment attributes, 2) develop a sustainability assessment model for buildings, 3) build a sustainability scale and 4) establish a sustainability-based rehabilitation model for existing buildings. The research utilized several modelling techniques, such as fuzzy TOPSIS technique to determine the weight of each assessment attribute, simulation to determine the energy consumption, BIM-based model to assess building sustainability and the artificial immune system (AIS) to develop the sustainability-based rehabilitation model. Several types of data were collected and used to develop the aforementioned models utilizing questionnaires, case studies and interviews with facility managers from Canada and Egypt. 
The results showed the significant influence of the regional variations on both the weights of the sustainability attributes and the total sustainability assessment. By using a scale from zero to one, Canada showed the highest weights in energy, indoor environmental quality (IEQ) and building management criteria with values of 0.220, 0.167, and 0.156, respectively, whereas in Egypt, energy, site and water use criteria possessed the highest weights with values 0.2, 0.191 and 0.169, respectively. The sustainability-based rehabilitation model was implemented with a case study in Canada in which the results showed the capability of the developed optimization model to determine several optimal or near optimal alternatives to upgrade the sustainability with minimal life cycle cost (LCC). The developed tool was validated by experts through an interview and questionnaires showing the potential application of the tool to existing buildings. The assessment model was also validated through a comparative analysis between the proposed model and other well-known sustainability rating tools, which showed good potential. Sensitivity analysis was conducted showing the impact of the weight variation on the sustainability assessment. The research concluded the importance of introducing a multi-level weighting scheme in the assessment to reflect regional variations. 
The main contribution of the present research is to provide decision-makers with a two-tier tool that 1) determines the current sustainability of buildings and highlights the weak areas that require more attention, and 2) proposes various rehabilitation alternatives that upgrades the sustainability of the building with minimal LCC utilizing multi-objective optimization. The research also contributes to the body of knowledge by developing an integrated sustainability assessment and rehabilitation framework as a step towards establishing a comprehensive global sustainability-assessment tool.

Integrated Sustainability Assessment and Rehabilitation Framework for Existing Buildings

This paper presents the effect of total harmonic distortion (THD) in power factor correction (PFC) at non-linear load. This study focuses on the relationship between THD and PFC. This is beacuse,the power factor affects THD. This occurs in power system as we have variety of loads, i. e linear load or non-linear load. The variety of loads will influence the sinusoidal waveform, which comes out from harmonic distortion. Thus, based on this study, we can compare the effective method in improving the power factor as it will not disturb the performance of THD. The focus of study is on the single phase load, where the voltage restriction is 240 V.  The analysis will  only focus on the consumer, which depends on the variety of non-linear load. Besides, the parameters for analysis are based on the percentage of THD and the value of power factor. The instrument for measuring the parameter is based on power factor correction device or technique. On the other hand, the method that was used for this study is based on simulation which incorporated the Multisim software. At the end of ths study, we can choose the most effective method that can be used to improve the power factor correction without disturbing the THD.

The Effects of Total Harmonics Distortion for Power Factor Correction at Non-Linear Load

This paper presents a new modeling and dynamic design for pump drive system utilizing MATLAB /SIMULINK Program to control the speed of motor. In this modeling we use MATLAB program implementation to reduce the energy consumption by the implementation of Variable Frequency converter (VFC) and hence the proper control of fluid flow rate.

https://www.irjet.net/archives/V3/i1/IRJET-V3I104.pdf

Dynamic Modeling of Pump Drive System utilizing Simulink/MATLAB Program

Many industrial applications require variable flow control of fluid (air, chemical gases, water and liquid chemicals). The traditional method of such flow control is to use an induction motor at constant speed with 50-Hz power supply and then control the flow by means of a throttle. Many fixed-speed motor load applications that are supplied direct from AC line power can save energy when they are operated at variable-speed, by means of VFD. Such energy cost savings are especially used in variable-torque centrifugal fan and pump applications, where the load's torque and power vary with the square and cube, respectively of the speed. This change gives a large power reduction compared to fixed-speed operation for a relatively small reduction in speed. Also by Using a variable frequency drive to control the fluid flow with a fully open throttle saves a considerable amount of power. As most of the drives operate at part load most of the time, the accumulated energy saving or the corresponding financial benefit, may be substantial over a prolonged period of time. Because this type of fluid flow control is common in industry, widespread application of variable-frequency drives with power electronics area can help in large energy conservation. The main aim of this paper is to reduce the energy consumption by the implementation of VFD and hence the proper control of fluid flows.

Energy Saving Mechanism Using Variable Frequency Drives

Dc power supplies are extensively used inside most of electrical and electronic appliances such as in computers, televisions, audio sets and others. Power supplies make the load compatible with its power source. The presence of non linear loads results into low power factor operation of the power system. Several techniques for power factor correction and harmonic reduction have been reported and a few of them have gained greater acceptance over the others. In this paper a bridgeless power factor correction boost converter is proposed which results in improved power factor and reduced harmonics content in input line currents as compared to conventional boost converter topology. Bridgeless power factor correction boost converter eliminates the line-voltage bridge rectifier in conventional boost power factor correction converter, so that the conduction loss is reduced.

Sri Shakthi

Papers

Energy Saving Mechanism Using Variable Frequency Drives

An Efficient AC/DC Converter with Power Factor Correction