Nature Inspired Meta-Heuristic Algorithm For Reduction in Real Power Loss and Improvement in Voltage Stability Limit of An Interconnected Power System Network

Vol. 4  Issue 2
Year: 2016
Issue:May-Jul
Title:Nature Inspired Meta-Heuristic Algorithm For Reduction in Real Power Loss and Improvement in Voltage Stability Limit of An Interconnected Power System Network
Author Name:P. Balachennaiah, and M. Suryakalavathi
Synopsis:

In this research work a meta-heuristic algorithm known as Firefly Algorithm (FA) is used for optimizing the control variables for simultaneously optimizing the transmission system's Real Power Loss (RPL) and Voltage Stability Limit (VSL). Mathematically, this problem can be expressed as nonlinear equality and inequality constrained optimization problem having an objective function with the integration of both RPL and VSL. Transformers taps, Unified Power Flow Controller (UPFC) location and its parameters like series injected voltage magnitude and phase angle of UPFC are incorporated in the form of control variables during the formulation of the problem. The effectiveness of the proposed algorithm has been verified on IEEE 14-bus system. Simulation outcomes received with this new FA algorithm have been compared with the Real Coded Genetic Algorithm (RCGA) for the single objective of minimization of RPL and multi-objective with respect to RPL minimization and VSL maximization. In this paper Interior Point Successive Linear Programming (IPSLP) technique is also considered for the single objective of RPL minimization to compare with the FA technique. The simulation results show the effectiveness and also the superiority of the FA with regard to optimizing both RPL and VSL.

SEPIC Based Multi-Stack Voltage Equalizer For Partially Shaded PV Modules Using Fuzzy Logic Controller

Vol. 4  Issue 2
Year: 2016
Issue:May-Jul
Title:SEPIC Based Multi-Stack Voltage Equalizer For Partially Shaded PV Modules Using Fuzzy Logic Controller
Author Name:R. Senthilkumar, D. Rajkumar and A. Mariya Sindhuja
Synopsis:

This paper presents an intelligent approach to the improvement and optimization of control performance of a photovoltaic system with multi-stacked voltage equalizer based on fuzzy logic controller. A single-switch voltage equalizer using multistacked SEPIC is proposed to settle the partial shading issues to extract maximum energy from the Photovoltaic (PV) Systems. The single-switch topology can considerably simplicity of the circuitry compared with conventional equalizers, requiring multiple switches in proportion to a number of PV module/substring. The proposed voltage equalizer can be derived by stacking capacitor-inductor-diode (CLD) filter on SEPIC converter. Local MPPs were eliminated and extractable maximum power was increased by the equalizer. Fuzzy logic algorithms are simulated using a MATLAB fuzzy logic toolbox. An Adaptive Fuzzy Logic Control (AFLC) algorithm is employed to online regulate the equalization period, according to the voltage difference between panel voltage, not only greatly abbreviating the balancing time, but also effectively preventing over-equalization. A prototype with three PV panels is implemented to this paper. The equalization efficiency is higher than 98% equalization compared with the traditional analog control algorithm. This paper explains the basic results of fuzzy logic algorithms and provides the better algorithm for maximum output voltage.

Optimization of Sequential Electricity Market Economics using UPFC in Deregulated Power System

Vol. 4  Issue 2
Year: 2016
Issue:May-Jul
Title:Optimization of Sequential Electricity Market Economics using UPFC in Deregulated Power System
Author Name:Varaprasad Janamala and K. Chandra Sekhar
Synopsis:

In a competitive market environment, the provision of strategic bidding to the market participants and its consequences open up new challenging tasks to the system operator. The market economic efficiency is mainly dependent on transmission system support. The inability of transmission system support to drive market cleared schedule is known as congestion which is not desirable. At first stage, Differential Evolution (DE) technique is applied to optimize unconstrained market schedules for active power demand. In the second stage, Time-Varying Acceleration Coefficients-Particle Swarm Optimization (TVAC-PSO) algorithm is applied to minimize reactive power cost by optimizing the Unified Power Flow Controller (UPFC) parameters and voltage profile of the network simultaneously. Due to this approach, the congestion cost with redispatch and more reactive power cost payment to the market participants have been avoided. In addition to this, the system maximum loadability has been reduced. The analysis is carried out on IEEE 14-bus and IEEE 30-bus test systems and the results shown the validity of the proposed work in real-time.

The Comparative Analyze of Solar Energy Production Potential Between Van and Antalya Using Simulation Program

Vol. 4  Issue 2
Year: 2016
Issue:May-Jul
Title:The Comparative Analyze of Solar Energy Production Potential Between Van and Antalya Using Simulation Program
Author Name:Abdülsamed Tabak, Mustafa Sacid ENDIZ
Synopsis:

This paper has been withdrawn by author.

An investigation into the future of sustainable power generation within the UK domestic sector

Vol. 4  Issue 2
Year: 2016
Issue:May-Jul
Title:An investigation into the future of sustainable power generation within the UK domestic sector
Author Name:Tom Page 
Synopsis:

Globally, the supply of fossil fuels is rapidly depleting and the effects of their use on the climate are becoming more noticeable. Recent European initiatives and renewable targets have increased the awareness of carbon emissions and the need for increased use of renewable sources. The UK government is committed to meeting an ambitious target of producing 15 percent of the UK's energy demand from renewable sources by 2020. The aim of the study is to discover how arise in sustainable power generation for the UK domestic sector could be achieved. This is achieved by analysing the current UK electricity consumption within the domestic sector, identifying the current renewable generation methods used and attaining expert views on renewables and their future prospect. Two semi-structured interviews with experts in the field of renewable energy were conducted. It is clear that both believe that the future of renewable energy within the UK will primarily be in the form of wind and solar power however, technologies such as wave and tidal power were also discussed which also have the potential to play a role in the future of UK energy. Through analysing all the research, recommendations have been made for the future of renewables within the UK. It has been suggested that the UK government expands the use of renewables, with the majority of development in solar and wind; increased use of domestic renewable sources and alter consumer behaviour; and finally, a recommendation for the government to establish an initiative to encourage consumers to time-shift when they use electricity to enable the use of energy from intermittent sources when available.

A Review on Single-Stage and Two-Stage Converter Using Photovoltaic Cell

Vol. 4  Issue 1
Year: 2016
Issue:Feb-Apr
Title:A Review on Single-Stage and Two-Stage Converter Using Photovoltaic Cell
Author Name:Vikash Kumar Rai, and Krishna Pratap Singh 
Synopsis:

In recent years, non conventional energy resources (solar energy, wind energy, tidal energy) has been the most effective utilization of generating electrical energy, and also widely used in transmission and distribution systems. In this paper, a study of two different photovoltaic systems, namely photovoltaic system using a single-stage converter and photovoltaic system using a two-stage converter has been analyzed. In a two-stage converter, the first stage has a DC-DC converter, which provides galvanic isolation and also changes the DC voltage level. The second stage has an inverter, which converts DC to AC and provides good quality current to the grid. In the single stage converter, flyback inverter is employed. This paper concludes with a discussion of the more efficient and reliable photovoltaic system between single and two stage systems.

Fuzzy Logic Based MPPT Scheme for SEPIC Converter in Photo-Voltaic System

Vol. 4  Issue 1
Year: 2016
Issue:Feb-Apr
Title:Fuzzy Logic Based MPPT Scheme for SEPIC Converter in Photo-Voltaic System
Author Name:Shweta Singh, and Awadhesh Kumar D
Synopsis:

In this paper a detailed description of fuzzy logic based MPPT (Maximum Power Point Tracker) scheme for the SEPIC converter is presented for tracking the maximum power point in the PV array. Due to the fact that the output of the solar panel is not linear in nature, it has a point of maximum power which changes due to the variation in irradiance and temperature. Thus, MPPT scheme provides an opportunity for a solar panel to operate continuously at peak power point. In this work, the authors have presented the co-ordinated sequences of P&O (Perturb and Observe) and fuzzy logic control are provided to form a single algorithm for MPPT of PV DC-DC SEPIC converter for PV inverter applications. For the SEPIC converter, the fuzzy logic MPPT scheme shows a high accuracy in the current waveform and provides a constant voltage waveform and is also utilized to get the accurate sine wave output of the inverter used in the PV system. Total Harmonic Distortion is also computed for the basis of representing harmonics in the sine wave output of the inverter used in the PV system.

Mitigation and Analysis of Very Fast Transient over Voltages (VFTOs) of Transformer in 1000kV Gas Insulated Substation (GIS) Using Wavelet Transform

Vol. 4  Issue 1
Year: 2016
Issue:Feb-Apr
Title:Mitigation and Analysis of Very Fast Transient over Voltages (VFTOs) of Transformer in 1000kV Gas Insulated Substation (GIS) Using Wavelet Transform
Author Name:Prakasam. K, Surya Kalavathi M, and Prabhavathi. D
Synopsis:

Mitigation and analysis of Very Fast Transient Overvoltages (VFTO) is very important in Gas Insulated Substations (GIS). In this paper, a power transformer rating of 400MVA in 1000kV gas insulated substation has been considered and different techniques for mitigation and analysis of Very Fast Transient Overvoltages (VFTOs) are applied and the outcomes are analyzed by the application of Discrete Wavelet Transform (DWT) as the wavelet transform is superior and a powerful tool for extraction of high frequency transient signals and gives the crisp output. The proposed system has been designed with MatLab platform and the designed system is simulated to evaluate the peak values of Very Fast Transient Overvoltages (VFTOs) generated both at transformer (Vtr) and open end of (Voc) with and without RC – filter, ferrite ring and a nonocrystilline. The results show that the peak value of Very Fast Transient Overvoltages (VFTOs) can be considerably reduced by introducing RC–filter ferrite ring and nanocrystalline methods. The outcomes are explored to wavelet transform for transient information. By the application of wavelet transform, it has concluded that an exact measurement VFTOs can be obtained and is shown in the results.

Power Quality Improvement of Grid Connected PV System Using Dynamic Voltage Restorer

Vol. 4  Issue 1
Year: 2016
Issue:Feb-Apr
Title:Power Quality Improvement of Grid Connected PV System Using Dynamic Voltage Restorer
Author Name:Vivekanand Rai and Kishan Bhushan Sahay
Synopsis:

Power quality problems are basically concerned with voltage fluctuations, voltage sag, swell, frequency distortions, and harmonics in the current at the load side. These problems lead to failure, and mis-operation of various sensitive loads. Distribution system networks, critical industrial loads and other commercial operations suffer from various power quality problems which can lead to considerable financial losses. This paper represents a grid connected PV based Dynamic Voltage Restorer (DVR) to mitigate deep voltage sags. The existence of three phase fault in the system affects the grid voltage and current. DVR injects voltage in series with the system to mitigate the voltage sag. An efficient DC-DC step up converter with a three level (6pulse) VSC (Voltage Source Converter) is utilised to give stable and harmonic free supply to the Grid. The simulation results and analysis show the validation of proposed DVR.

A Review on Power Quality Problems in Wind Energy Generation

Vol. 4  Issue 1
Year: 2016
Issue:Feb-Apr
Title:A Review on Power Quality Problems in Wind Energy Generation
Author Name:Bhanu Pratap Singh and S.K. Srivastava
Synopsis:

With the advancement of technology non-conventional resources of energy are playing a major role in generating electricity. Non conventional sources of energy are used in various forms of energy such as solar energy, wind energy, hydro power, geothermal energy, bio energy and various energy storages. The wind energy generation is one of the efficient source of generating electricity. The wind generating system is facing problem when connected to the grid which creates serious power quality issues and need to be solved. This paper presents the power quality issues concerned in wind energy generation, utilization and its grid penetration in an electrical grid. The fluctuations in wind generated power causes stability problems. The power quality of the wind generating source in the electrical network is affected by the weak interconnection of the source. Nowadays, there are various power quality issues such as voltage variation, flicker, active power, reactive power, harmonics and electrical behavior of switching operation. These are measured according to national/international guidelines. This paper mainly explains the power quality problem faced during the setting of wind turbines with the grid. Nowadays there is a huge improvement in technologies, and thus using various new techniques, the wind turbine [1] has to control the reactive power over a wide range.

Detection and Location of Faults in Three Phase 11kv Underground Power Cables By Discrete Wavelet Transform (DWT)

Vol. 3  Issue 4
Year: 2016
Issue:Nov-Jan
Title:Detection and Location of Faults in Three Phase 11kv Underground Power Cables By Discrete Wavelet Transform (DWT)
Author Name:Prabhavathi. D, Surya Kalavathi. M and Prakasam. K
Synopsis:

This paper presents detection and location of fault in underground cables by wavelet transform as it is one of the most efficient tools for analyzing non stationary signals and it has been widely used in electrical power systems. Estimation and determination of fault in an underground cable is very important in order to clear the fault quickly and to restore the supply with minimum interruption [3, 8].The high voltage power cable 500MVA, 11kV, 200 km is modeled in MAT LAB simulink platform. Mexican Hat and coif let wavelet transforms is used to extract the signals and the waveforms are shown. The simulation results shows that wavelet method is efficient and powerful to estimate the faults when they occurs in the underground cables.

Design and Study of Wind-Solar Hybrid System for Domestic Application

Vol. 3  Issue 4
Year: 2016
Issue:Nov-Jan
Title:Design and Study of Wind-Solar Hybrid System for Domestic Application
Author Name:Nikhil V Nayak, P.P. Revankar and M.B. Gorawar
Synopsis:

The Government of India has sanctioned funds for production of 190 GW in this direction and this solution is a way to reduce the pollution levels. This support of the go-green initiative by the united nations as well and is a step forward in creating a better environment for the future generations to live in. The proposed work aimed at designing a wind-solar hybrid system for light load application. The tools like Qblade and solidworks were used to model and analyze the wind turbine system, the material used for the blade and hub was balsa wood and the tower a tripod type. The power output of 100 W at an average wind speed of 4.5 m/s has been targeted. The work also aimed at providing electricity to the rural area in India which amount to 25000 in number where there is no provision for electricity, this solution may provide the electricity needs of such villages.

Improvement of Power Quality With Multi Input Renewable Energy Sources for Non-Linear Load

Vol. 3  Issue 4
Year: 2016
Issue:Nov-Jan
Title:Improvement of Power Quality With Multi Input Renewable Energy Sources for Non-Linear Load
Author Name:S. Kamalakkannan and D. Kirubakaran
Synopsis:

In this paper voltage source converter is interfaced with renewable energy sources such as solar and wind for power quality improvement. The output of a wind energy conversion system is given as one input to the voltage source converter. Perturb and observation based solar panel is projected for changing irradiance to utilize the maximum obtainable power from the solar panel. The output of wind energy conversion system along with output of solar panel is given to voltage source converter wherein the DC is converted to AC with improvement of power quality. A DC link bus connects both the converters of voltage source converters and AC output of converter is given to non-linear load through a grid connected system. Different digital simulation results are acquired to validate features of voltage source converter for multi input renewable energy sources

Measurement and Classification of Power Quality Disturbances Using Wavelet Based Neural Network

Vol. 3  Issue 4
Year: 2016
Issue:Nov-Jan
Title:Measurement and Classification of Power Quality Disturbances Using Wavelet Based Neural Network
Author Name:S. Deb and S. Patra
Synopsis:

This paper presents an approach for measuring and classifying power quality disturbances using discrete wavelet transform and artificial neural network. The various power quality events are considered they are voltage sag, swell, harmonics, sag with harmonics, swell with harmonics and interruption. Due to the power quality disturbances, the signal is distorted. The energy of the distorted signal is first evaluated with the help of the Multi-Resolution Analysis (MRA) technique of Discrete Wavelet Transform (DWT) and the Parseval's theorem. Second, the energy deviation of the distorted signal with respect to pure sinusoidal signal is at different levels calculated. From these energy features and transient duration the artificial neural network classifies and identifies the disturbances.

Analysis of Optimal Power Flow Using Gravitational Search Algorithm

Vol. 3  Issue 4
Year: 2016
Issue:Nov-Jan
Title:Analysis of Optimal Power Flow Using Gravitational Search Algorithm
Author Name:M. Lakshmikantha Reddy, M. Ramprasad Reddy and V.C. Veera Reddy
Synopsis:

The operation of an electric power system is a complex one due to its nonlinear and computational difficulties. One task of operating a power system economically and securely is optimal scheduling, commonly referred to as the Optimal Power Flow (OPF) problem. It optimizes a certain objective function while satisfying a set of physical and operating constraints. Optimal power flow has become an essential tool in power system planning and operation. In this paper, a gravitational search algorithm is presented to solve OPF problems while satisfying system equality, in-equality constraints. The effect of security limits such as transmission line limits and load bus voltage magnitudes is also analyzed on OPF problem. The developed methodology is tested on the standard IEEE-30 bus test system, supporting numerical and as well as graphical results.

Power Conditioning System for a Solar Photovoltaic System Using Level Shift Sinusoidal PWM

Vol. 3  Issue 3
Year: 2015
Issue:Aug-Oct
Title:Power Conditioning System for a Solar Photovoltaic System Using Level Shift Sinusoidal PWM
Author Name:Mahesh Babu, K.K. Deepika and B. Jyothi 
Synopsis:

Maximum Energy can be extracted from the popularly used PV systems by using Power conditioner circuit. Power conditioner controlled with FPGA is implemented in this paper. Variable DC power from the solar array [33][34] is converted to constant DC voltage using a Boost converter. FPGA controller adjusts the pulse width to maintain the output voltage of the boost converter constant. The obtained constant DC voltage is converted to 3-phase AC using a 3-Phase 3-level diode clamped inverter. Reference current at AC side of the inverter is controlled by current control MPPT based on six-region operation. 2-stage power conditioner for the Solar PV system is developed in MATLAB Simulink and Xilinx System generator tool. Simulated results are analysed using Bode plot and THD analysis.

Transmission Power Flow Tracing and Loss Allocation using Proportional Sharing

Vol. 3  Issue 3
Year: 2015
Issue:Aug-Oct
Title:Transmission Power Flow Tracing and Loss Allocation using Proportional Sharing
Author Name:G. Venkata Sai Siva Kumar and D. Ragaleela
Synopsis:

Deregulation is the major trend in the electric power industry throughout the world, in which restructuring of electricity network was done to access power from any generator to any load and to introduce competition by paving way for the private participants. In this transmission, network plays a very important role. One of the key issues of this restructured power system is, power loss allocation that needs to access what impact of particular generator or load on power system, for which power flow is to be traced along the lines. Tracing of power determine the contribution of transmission users to transmission usage, also helps to meet the revenue expectations and support efficient operation of electrical markets and adequately reimburse owners of transmission assets, in this view tracing of electricity has gained significance. In this paper, power flow tracing using AC power flow and the proportional sharing principle has been attempted, which is Bialek's power flow tracing which comes in two flavors, up-stream and down-stream algorithms by considering gross, net and average power flows in the network. The application of these techniques are explained, tested on IEEE-14 bus system and results are compared between all approaches using MATLAB.

Implementation of Capacitor Banks for Fixed Compensation to Improve the Performance of the Captive Generator in Petrochemical Industry

Vol. 3  Issue 3
Year: 2015
Issue:Aug-Oct
Title:Implementation of Capacitor Banks for Fixed Compensation to Improve the Performance of the Captive Generator in Petrochemical Industry
Author Name:Meenakshendra A. Khamitkar, S.G. Ankaliki and Gururaj Rao 
Synopsis:

This paper presents the design and implementation of capacitor banks to improve the performance of captive generation in petrochemical industry. Now-a-days many industries faces the problem of maintaining power quality during scheduled power outages. While transferring the load from utility supply to the captive generation supply, facing the problem of voltage dip due to heavy loading condition, affects the system performance. In order to overcome this problem, situation was analyzed and suggested to install capacitor banks at the generator feeder to improve the system performance. Power World simulator is used to analyze the problem and to observe the performance of the system after the installation of the capacitors. The case study of petrochemical industry has been taken to identify the actual problem analysis and its solution.

Enhancement of System Stability using Static Synchronous Series Compensator

Vol. 3  Issue 3
Year: 2015
Issue:Aug-Oct
Title:Enhancement of System Stability using Static Synchronous Series Compensator
Author Name:Anil Kumar and S.K.Srivastava
Synopsis:

Today, modern power system carries very high demand from the load side. Thus, they cause the stability problem. This paper investigates the problem related to the voltage stability in the power system and controlling the power flow through transmission line using a FACT controller known as Static Synchronous Series Compensator (SSSC). In this paper, the FACT controller investigates the effects for controlling the active and reactive power as well as damping power system oscillation that occur because of the heavy loaded system. Under heavy loaded conditions, there may be insufficient reactive power causing the voltage to drop. This voltage may lead to drop in voltage at various buses. Flexible AC Transmission System (FACTS) controller have been mainly used for various power system stability. In this paper, the authors used a Pulse Oscillation Damping controller with SSSC to damp out the system oscillation and maintain the stability of the power system. The SSSC equipped with source of energy in dc link can supply or absorb the active power to or from the line along with the reactive power flow control. The SSSC is represented by a variable voltage injection with associated transformer leakage reactance and voltage source.

Computation of 400kV Phase and Sequence Impedance Matrices Signifying Transposition

Vol. 3  Issue 3
Year: 2015
Issue:Aug-Oct
Title:Computation of 400kV Phase and Sequence Impedance Matrices Signifying Transposition
Author Name:G.Radhika and M.Suryakalavathi
Synopsis:

Electrical power systems usually cover large geographical areas and transmission facilities, that are incessantly increasing. These power systems when exposed to different environmental conditions may cause severe faults to occur on the existing system. In this paper, the need for transposing the lines for analysing the faults under phase and sequence frame of reference has been described. Currents flowing in any one conductor will induce voltage drops in the other successive conductors and these may be unequal even though the currents are balanced which is highly objectionable. In order to minimize the effect of line unbalance, there is a chance of interchanging the conductor positions at their regular intervals along the line, termed Transposition. The objective of this paper is to show the effect of transpositions in producing equal series self and mutual impedances in the phase and sequence frame of reference for a chosen 400 kV, double circuit, single ground wire tower configuration. It is also shown that, by applying nine transpositions technique, the effect of mutual sequence coupling between the two circuits is eliminated completely and balanced phase impedance matrix of 6X6 is obtained. The calculations of overhead lines for different tower configurations was carried out using digital computer program MATLAB and results obtained conventionally shows an excellent resemblance in obtaining balanced phase and sequence impedance matrices. Thus, the same simulation can be used for any tower configuration.

Automation of Electrical Power Distribution System

Vol. 3  Issue 2
Year: 2015
Issue:May-Jul
Title:Automation of Electrical Power Distribution System
Author Name:Roshny Mathew, M. S. Srinath and N. S. Jyothi
Synopsis:

Today energy is the most important basis for development of any country. Generation, transmission, distribution, and usage of energy are to be optimized for the proper conservation of energy. Electrical energy is generated from different sources like hydraulic power plants, thermal power plants, nuclear power plants etc. India has ample water sources to produce electrical energy. Presently the long time outage and fault detection during distribution are very serious problems. Also accidents are not uncommon in electrical transmission systems. It is too late to implement advanced systems for power distribution systems, if not implemented now. The main focus of the present work is to modernize the present systems with powerful tools like PLC and SCADA for automatic control of distribution systems. The automatic tap changer maintains the voltage of whole system normally. Thus much manpower could be reduced and major outages can be avoided with maximum safety of the system.

Detection of Voltage SAG Using Hilbert-Haung Transform

Vol. 3  Issue 2
Year: 2015
Issue:May-Jul
Title:Detection of Voltage SAG Using Hilbert-Haung Transform
Author Name:Ch. Sri Swathi and M. Saiveerraju
Synopsis:

In this paper a method is proposed to detect voltage sag based on Empirical Mode Decomposition (EMD) with Hilbert Transform (called Hilbert-Huang Transform).The main characteristic feature of EMD is that it decomposes a nonstationary signal into mono component and symmetric signals called Intrinsic Mode Functions (IMFs). Further, the Hilbert transform is applied to each IMF to extract the features. The magnitude plot of the Hilbert Transform of one of the IMF correctly detects the event. Three voltage sag causes are taken in this paper (i) fault induced voltage sag, (ii) starting of induction motor and (iii) three phase transformer energization. Simulation/matlab results show the effectiveness of this method.

Optimum Allocation and Sizing of DG to Reduce Losses and Improve Voltage Profile by ABC Algorithm

Vol. 3  Issue 2
Year: 2015
Issue:May-Jul
Title:Optimum Allocation and Sizing of DG to Reduce Losses and Improve Voltage Profile by ABC Algorithm
Author Name:D. Chinna Kullay Reddy, P. Murthy, S. Mallikarjunaiah and V. Ganesh
Synopsis:

A method proposed here for the placement of Distributed Generation (DG) in electrical distribution system in order to reduce the system power loss and voltage profile improvement. The DG real and reactive power injections typically installed near to the load centers and distribution system voltage support energy savings, and reliability improvement by reducing the losses in the system. This work focuses on the ancillary service of real power and also both real and reactive power support provided by DG. Artificial bee colony algorithm (ABC) is proposed to find the DG optimal size and location by using Loss Sensitivity Index (LSI) in order to minimize the total system real power loss. Simulation studies are examined on 33 and 69-bus radial test system to validate the proposed method with existing method.

Design of PV-Wind Hybrid Micro-Grid System for Domestic Loading

Vol. 3  Issue 2
Year: 2015
Issue:May-Jul
Title:Design of PV-Wind Hybrid Micro-Grid System for Domestic Loading
Author Name:Ankush Kumar, Menghal and Jaya Laxmi 
Synopsis:

Now-a-days Renewable Energy Sources like Solar and Wind are becoming popular for household applications. Solar power is available in daytime only and there is no method of developing power for night loads except the use of power stored in batteries. Wind energy is the alternate energy available. A better solution for the above situation is the combination of PV and Wind to form a hybrid system for domestic loading. Integration of PV and Wind systems in the form of AC faces many difficulties such as synchronizing of phase, amplitude and frequency of the voltages. To avoid the complexities of integration in AC, this paper presents a simple way for integration in the DC form.

This paper presents a case study of JNT University Campus, where a fault is applied to JNTU network as a consideration of natural disaster. Under these conditions the power from Main Grid is turned off and the alternate power for desired loads is obtained from the PV-Wind hybrid system.

Dynamic Stability and Analysis of SMIB System with Power System Stabilizers Using Different Techniques

Vol. 3  Issue 2
Year: 2015
Issue:May-Jul
Title:Dynamic Stability and Analysis of SMIB System with Power System Stabilizers Using Different Techniques
Author Name:Pothula Jagadeesh and M. Sai Veerraju
Synopsis:

A Power System Stabilizer (PSS) installed in the excitation system of the synchronous generator improves the small-signal power system stability by damping out low frequency oscillations in the power system. This paper introduces the dynamic stability and analysis of a single machine connected to the infinite bus system (SMIB) with a power system stabilizer which is tuned with different controllers like fuzzy logic controller, PI and PID controllers which have been designed to provide a supplementary signal to the excitation system of the synchronous generator including the load damping parameter sensitivity. The simulations have been tested under different fault conditions and the obtained results show that the proposed controller for stabilizing power system can provide very good damping characteristics, compared to the conventional PSS and FPSS, through wide range of operating conditions for power system, and improves dynamic stability of the power system substantially. The responses for these different controller based PSS are compared. Matlab- Simulink is used to test the results.

Comparative Analysis of Advanced OCV Prediction Mechanism for Batteries Used in Vehicular Systems

Vol. 3  Issue 2
Year: 2015
Issue:May-Jul
Title:Comparative Analysis of Advanced OCV Prediction Mechanism for Batteries Used in Vehicular Systems
Author Name:Kary Thanapalan, Mark Bowkett, Thomas Stockley, Alessandro Mariani and Jonathan Williams
Synopsis:

This paper presents an advanced Open Circuit Voltage (OCV) prediction technique for battery cells. The work contains an investigation to examine the relaxation voltage curves, to analyse the potential for the OCV prediction technique in a practical system. The technique described in this paper employs one simple equation to predict the equilibrated cell voltage after a small rest period. The practical work detailed in this paper was conducted at the Center for Automotive and Power System Engineering (CAPSE) battery laboratories at the University of South Wales (USW). The results indicate that the proposed OCV prediction technique is highly effective and using this technique appreciable benefit can be accrued.