WSEAS Transactions on
Power Systems

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Print ISSN: 1790-5060
E-ISSN: 2224-350X

Volume 10, 2015

Notice: As of 2014 and for the forthcoming years, the publication frequency/periodicity of WSEAS Journals is adapted to the 'continuously updated' model. What this means is that instead of being separated into issues, new papers will be added on a continuous basis, allowing a more regular flow and shorter publication times. The papers will appear in reverse order, therefore the most recent one will be on top.

Volume 10, 2015

Title of the Paper: Some Aspects of Electric Power Equipment Modelling through Sustainability Key Concepts

Authors: Cornelia A. Bulucea, Doru A. Nicola, Marc A. Rosen, Nikos E. Mastorakis, Carmen A. Bulucea

Abstract: Enhancements are made to the concept that technical systems and processes involving energy conversion, and particularly electric power equipment, need to be linked to environment engineering, since the concept of sustainable development should emphasize two complementary aspects. The first is related to the design of electrical equipment in order to achieve high energy efficiency during all life stages of a system, and the second takes into consideration the environmental impact of technical systems operation, since biological ecosystems generally are not free of anthropogenic influences. These are the reasons that, over the last few decades, international legislation has required environmental impact assessment to be carried out for all phases of the life electrical equipment, according to Life Cycle Assessment, which includes the production, use and end-of-life phases. Following the notion that Nature demonstrates sustainable energy conversion, this work focuses on highlighting that industrial ecology permits an alternate view of anthropogenic applications, related both to technical and environmental reference systems. The study addresses some aspects, using energy conversion processes during the operation of power transformers and induction motors as modeling examples of sustainable electric equipment. Based on the model equations, this article presents the structural diagrams method, as a modeling method for a three-phase electric transformer and induction motor in dynamic regimes, according to an ecosystem pattern. The overall objective is to enhance understanding of how anthropogenic activities can be viewed in concert with the entire system on Earth.

Keywords: Electric power equipment, electromagnetic torque, exergy, induction motor, power transformer, structural diagram, sustainability dynamics

WSEAS Transactions on Power Systems, ISSN / E-ISSN: 1790-5060 / 2224-350X, Volume 10, 2015, Art. #28, pp. 268-278

Title of the Paper: Proposal of Multidisciplinary Design Optimization Approach for a Proton Exchange Membrane Fuel Cell Performance Estimate

Authors: Enrico Testa, Paolo Maggiore, Lorenzo Pace, Matteo D. L. Dalla Vedova

Abstract: The amount of current density the stack is able to produce is the key performance indicator for a fuel cell system; at given chemical conditions and geometry, the leading parameters in a Proton Exchange Membrane fuel cell behavior are the exchange current density, both at anode and cathode, as well as the temperature and relative humidity at the anode. Such considerations lead to the definition of a surrogate model that is subsequently validated. Such model is then used as the basis for a Multidisciplinary Design Optimization process based. A comparison among suitable approximation methods is considered with the aim to reduce the computational time. The presented work focuses on two unconstrained single-objective optimization processes to find the best solution in terms of maximum current density produced at a given voltage. Finally, the optimized outputs are validated.

Keywords: PEM Fuel Cell, Multidisciplinary Design Optimization, Sensitivity Analysis, Monte Carlo Simulation, Surrogate Model

WSEAS Transactions on Power Systems, ISSN / E-ISSN: 1790-5060 / 2224-350X, Volume 10, 2015, Art. #27, pp. 259-267

Title of the Paper: Preventive Risk-Management of Power System for its Reliability Increasing

Authors: Mykola V. Kosterev, Eugen I. Bardyk

Abstract: In article is considered the problem of effective Electrical Power System management in the conditions of incomplete information about regimes and technical stuff of equipment and in the conditions of financial restrictions. Fault probability and accident risk are proposed as the criteria for the effective Electrical Power System management. Using these criteria allows increasing reliability of Electrical Power System and its elements. For the decreasing accident risk and increasing Electrical Power System reliability Pareto optimal method is used. Developed approaches, methods and algorithms are checked on IEEE test scheme.

Keywords: fault, risk, probability, Electrical Power System, technical stuff, Pareto method

WSEAS Transactions on Power Systems, ISSN / E-ISSN: 1790-5060 / 2224-350X, Volume 10, 2015, Art. #26, pp. 251-258

Title of the Paper: A Hybrid Optimization Algorithm (IA-PSO) for Optimal Coordination of Directional Overcurrent Relays in Meshed Power Systems

Authors: Mohamed Zellagui, Heba Ahmed Hassan

Abstract: This paper presents a hybrid optimization approach for the optimal coordination of Inverse Definite Minimum Time (IDMT) directional overcurrent relays in meshed power systems, namely Immune Algorithm and Particle Swarm Optimization (IA-PSO) algorithm. The algorithm is employed by coupling the immune information processing mechanism with the particle swarm optimization algorithm in order to achieve a better global solution with less computational effort. In protection coordination problem, the objective function to be minimized is the sum of the operating time of all main relays. The optimization problem is subject to a number of constraints which are mainly focused on the operation of the backup relay, which should operate if a primary relay fails to respond to the fault near to it, Time Dial Setting (TDS), Plug Setting (PS) and the minimum operating time of a relay. The proposed optimization algorithm aims to minimize the total operating time of each protection relay. Two systems are used as case study to check the efficiency of the optimization algorithm which are IEEE 4-bus and IEEE 6-bus models. Results are obtained and presented for IA and PS and IA-PSO algorithms. The obtained results for the studied cases are compared with those results obtained when using other optimization algorithms which are Teaching Learning-Based Optimization (TLBO), Chaotic Differential Evolution Algorithm (CDEA) and Modified Differential Evolution Algorithm (MDEA). From analysing the obtained results, it has been concluded that IA-PSO algorithm provides the most optimum solution with the best convergence rate.

Keywords: Meshed Power Systems, Directional Overcurrent Protection Relays, Optimal Coordination, Immune Algorithm, Particle Swarm Optimization, Hybrid Optimization Algorithms

WSEAS Transactions on Power Systems, ISSN / E-ISSN: 1790-5060 / 2224-350X, Volume 10, 2015, Art. #25, pp. 240-250

Title of the Paper: BAT Search Algorithm for Power System Stabilizers Design in Multimachine System

Authors: E. S. Ali

Abstract: A new metaheuristic method, the BAT search algorithm based on the echolocation behaviour of bats is proposed in this paper for optimal design of Power System Stabilizers (PSSs) in a multimachine environment. The PSSs parameter tuning problem is converted to an optimization problem which is solved by BAT search Algorithm. An eigenvalues based objective function involving the damping factor, and the damping ratio of the lightly damped electromechanical modes is considered for the PSSs design problem. The performance of the proposed BAT based PSSs (BATPSS) has been compared with Genetic Algorithm (GA) based PSSs (GAPSS) and the Conventional PSSs (CPSS) under various operating conditions and disturbances. The results of the proposed BATPSS are demonstrated through time domain analysis, eigenvalues and performance indices. Moreover, the results are presented to demonstrate the robustness of the proposed algorithm over the GA and conventional one.

Keywords: Power System Stabilizers, BAT Search Algorithm, Genetic Algorithm, Multimachine System, Power System Stability, Low Frequency Oscillations

WSEAS Transactions on Power Systems, ISSN / E-ISSN: 1790-5060 / 2224-350X, Volume 10, 2015, Art. #24, pp. 230-239

Title of the Paper: Bee Algorithm Optimization for Load Management Based On Load Shifting in the Textile Industry

Authors: Chaimongkon Chokpanyasuwan, Kodchasorn Hussaro, Tika Bunnag, Ratthasak Prommas

Abstract: This paper proposes an application of bee algorithm (BA) with compare GA and PSO method to develop the load shifting and the same has been tried with the actual load data collected from the textile industry plant. The target of any load management is to maintain a constant level of load. The important benefits of load management are reduction in maximum demand, reduction in power loss, better equipment utilization and saving through reduced maximum demand charges. Load shifting, one of the simplest method of load management, is to reduce customer demand during the peak period by shifting the use of appliances and equipment to partial peak and on-peak periods. The objective is to minimize the total electricity cost. The methodology proposed can be used for determining the optimal response for textile industry under time varying tariffs such as flat rate and time of use (TOU).To show its efficiency, the bee algorithm is applied to solve the case studies in case of single process multi-jobs (SPMJ). The results show that the proposed method is able to achieve the best solution efficiently and easy to implement.

Keywords: Load management, Time of used, Bee Algorithm, Textile Industry Optimization

WSEAS Transactions on Power Systems, ISSN / E-ISSN: 1790-5060 / 2224-350X, Volume 10, 2015, Art. #23, pp. 215-229

Title of the Paper: Firefly Algorithm Based Speed Control of DC Series Motor Powered by Photovoltaic System

Authors: E. S. Ali

Abstract: This paper presents the speed control of DC series motor supplied by Photovoltaic (PV) system. The proposed design problem of speed controller is formulated as an optimization problem. Firefly Algorithm (FA) is employed to search for optimal Proportional Integral (PI) parameters of speed controller by minimizing the time domain objective function. The performance of the proposed FA based speed control of DC series motor has been compared with Genetic Algorithm (GA) and the Conventional PI controller tuned by Ziegler Nichols (ZN) under various operating conditions and disturbances. The results of the proposed FA are demonstrated through time domain analysis, and various performance indices. Simulation results have shown the validity of the proposed technique in controlling the speed of DC series motor over GA and conventional algorithm.

Keywords: DC Series Motor, Firefly Algorithm, Genetic Algorithm, Photovoltaic System, PI Controller, Speed Control

WSEAS Transactions on Power Systems, ISSN / E-ISSN: 1790-5060 / 2224-350X, Volume 10, 2015, Art. #22, pp. 204-214

Title of the Paper: Comparison Test the Difference between Rectangular Patch Antenna and Conical Antenna for Harvesting Energy Inside the Pipeline

Authors: Mohamed Zied Chaari

Abstract: The purpose of this paper is to develop and check the difference between the rectangular patch antenna and the conical horn antenna for fastening the maximum of energy propagation inside- thought-the pipeline for charging the battery of robot Crawler [1]. This paper presents the idea to use the pipeline as a circular waveguide to minimize the attenuation of energy as well as to maximize the power recovered to the level of antenna. Receiving and converting microwave energy into Directly Current (DC) that is a receiving antenna covers a large area, allows having relatively high effective radiated power and acceptable gain. This research document suggests a novel methodology using a novice technique to transfer energy using the oil and gas pipeline as a circular waveguide. We search each antenna can use for harvesting the maximum of energy inside the truck line.

Keywords: Conical horn antennas, rectangular patch antenna, circular waveguides, pipeline, pipe inspection robotic crawler, harvesting circuit

WSEAS Transactions on Power Systems, ISSN / E-ISSN: 1790-5060 / 2224-350X, Volume 10, 2015, Art. #21, pp. 198-203

Title of the Paper: An Efficient and Reliable Method for Optimal Allocating of the Distributed Generation Based on Optimal Teaching Learning Algorithm

Authors: Mahdi El-Arini, Ahmed Fathy

Abstract: This paper presents an improved methodology based on Teaching Learning Based Optimization (TLBO) algorithm which applied for determining the optimal number, allocation and size of distributed generation (DG) to reduce the active power loss and improve the voltage profile of the network. The improved TLBO algorithm is based on the updating process in the learner phase based on the interaction between the learners and the teacher by adding a weighting factor represents the importance of the obtained solution. A constrained objective function presents the system power loss and voltage profile of the network has been suggested. The results obtained from TLBO algorithm is compared to three different intelligent optimization algorithms, genetic algorithm (GA), particle swarm optimization (PSO) and cuckoo search (CS). The analysis has been applied on two different systems, 9-bus system and IEEE 57-bus system. The results showed that the proposed TLBO algorithm is efficient and reliable method in solving the problem compared to other algorithms.

Keywords: Distributed Generation, TLBO algorithm, Objective function

WSEAS Transactions on Power Systems, ISSN / E-ISSN: 1790-5060 / 2224-350X, Volume 10, 2015, Art. #20, pp. 188-197

Title of the Paper: Analysis of the Criterion for Connecting New Source to Distribution Grid According to the Steady State Evaluation

Authors: Martin Liska, Zaneta Eleschova, Peter Janiga, Marian Ivanic, Anton Belan

Abstract: Nowadays power systems, especially the electrical distribution grids are accommodating different renewable technologies resulting into increasing complexities and instabilities. The dynamic growth towards to renewable energy is measured by also considering the impact of distributed generation on the grids. Distributed generation is the electricity production from small sources and is located close to the final consumer. The purpose of distributed generation deployment is to improve the energy independence and if appropriate technology is used, distributed generation can participate on grid control actions. Besides the declared advantages in favor of distributed generation, the responsible bodies have to take measures to ensure the advantages will become visible. The base of safe and sustainable distributed generation deployment is the planning and setting the national targets based on the technical assessment. With planning national aims for renewable energy sources is necessary to regard various technical restrictions. One of the basic criteria for connecting new source to distribution grids is to adhere the voltage limits in networks. In efforts to estimate the impact of operation of a new source on voltage, distribution network operators define a criterion for the maximum permitted voltage change in steady state operation. This article deals with analysis of a voltage criterion and compares it with steady state calculation using the simulation model of 22kV feeder.

Keywords: simulation model, steady state, swing bus, voltage change, new source, criterion

WSEAS Transactions on Power Systems, ISSN / E-ISSN: 1790-5060 / 2224-350X, Volume 10, 2015, Art. #19, pp. 180-187

Title of the Paper: Sensitivity Analysis for a PEM Fuel Cell Model Aimed to Optimization

Authors: E. Testa, P. Maggiore, L. Pace, M. D. L. Dalla Vedova

Abstract: The amount of current density produced by the stack is the key performance parameter for a fuel cell, given a well-defined quantity of reactants flowing through it. A Proton Exchange Membrane fuel cell (PEMFC) distributed parameters model is considered with all the aspects influencing the cell behavior. A sensitivity analysis is performed through a Monte Carlo Simulation to assess the impact on performances of key parameters. The Pareto plot obtained from such analysis allow to operate design variables reduction, aimed to those parameters that show small impact, so to decrease the problem complexity through an increased orthogonality of the input design matrix. The target of the activity is to obtain and validate a method able to reduce the time needed for a complete simulation, so to be able to realize an effective multi-disciplinary design optimization.

Keywords: MDO, PEM fuel cell, Surrogate model, Numerical Simulation

WSEAS Transactions on Power Systems, ISSN / E-ISSN: 1790-5060 / 2224-350X, Volume 10, 2015, Art. #18, pp. 171-179

Title of the Paper: Computation of Reactive Power by Power Components in Practical Power Systems

Authors: M. Susithra, R. Gnanadass

Abstract: In order to meet the growing load demand, the power utilities are transferred to restructuring process. The reactive power is the supporting power which is necessary for real power transfer. Line charging capacitance, Capacitors, Generators, Synchronous condensers can produce reactive power. So, it is mandatory to know the contribution of reactive power delivered by these regulating devices for the particular load condition. This paper presents the intuition of power flow tracing techniques to determine the amount of reactive power delivered by the regulating devices. The results are compared with using three different reactive power evaluation methods namely Equivalent reactive compensation method, Modified Ybus method, Virtual power flow approach method. The contribution of individual power sources towards the reactive power is demonstrated by using IEEE30 bus system as test system.

Keywords: Equivalent reactive compensation method, Modified Ybus method, Virtual power flow approach method, Modified power flow tracing method, Upstream algorithm, Downstream algorithm

WSEAS Transactions on Power Systems, ISSN / E-ISSN: 1790-5060 / 2224-350X, Volume 10, 2015, Art. #17, pp. 157-170

Title of the Paper: Micro-Grid Droop Control Strategy and Isolated Island Operation System Stability Analysis

Authors: Li-Jun Qin, Wan-Tao Yang

Abstract: In the micro-grid, droop control strategy simulates traditional power system droop characteristics , by changing the output of active and reactive power to control the output voltage frequency and amplitude, thus the micro-grid system can work at the stabilize voltage point in island operation mode . And the voltage is more or less with the grid-connect mode,so that the transition is smooth when switching,which can guarantee the load work undisturbed. Microgrid based on droop control can achieve automatically adjust voltage and frequency, without the aid of communication, which can improve system reliability, and easy to implement micro-power and load plug and play. We designed specifically simulation circuit for the droop control strategy on PSIM . And the output waveform is studied. Simulation results show the schematic design of the control strategy is correct.We established an island microgrid complete small-signal state space model, which took into account the inverter power small-signal sub-model, network lines and the load small signal sub-model.It use eigenvalue method to analysis microgrid small signal model state matrix, to get the following conclusions: droop coefficient increases will reduce the stability of the micro-grid system; when the line impedance is smaller, micro-grid is easy to lose stability. Finally, We use the simulation tools to verify the small signal stability analysis conclusions is correct.

Keywords: Microgrid, droop control, PSIM, Simulink, converter, small signal stability analysis

WSEAS Transactions on Power Systems, ISSN / E-ISSN: 1790-5060 / 2224-350X, Volume 10, 2015, Art. #16, pp. 145-156

Title of the Paper: A New Control Strategy to Enhance Lvrt for Doubly Fed Induction Generator

Authors: K. Gunalan, C. Sharmeela

Abstract: Nowadays renewable energy resources had became more important for dropping the green house gases. Since the renewables installed in utility grid gets increasing, stabilizing the power systems becomes a major issue. For renewables integration into the utility grid, the specific requirement should be placed by the grid operators. Among grid codes issues Low-voltage ride-through (LVRT) is a most important one. In wind power system, for certain period of time the power converters are demanded by grid codes to remain coupled with grid in the event of voltage drop. In this paper a new modified computational intelligence based control strategy is proposed to enhance the LVRT capability of grid connected doubly fed induction generators (DFIG). To support grid voltage during and after the fault, wind turbine (WT) should supply reactive power to the grid which is the world–wide requirement of grid codes. To protect the rotor side converter from grid faults a conventional crowbar-based systems were used, but this method fail to fulfill the requirement since DFIG acts as squirrel cage machine during the connection of crowbar and it absorbs reactive power from the grid. This makes to design a control system without using crowbar. In order to overcome the drawbacks mentioned above, this paper proposed the new coordinated control strategy of DFIG converters which can manage to ride-through the fault without any secondary hardware. This is achieved by using fuzzy logic controller which is tuned properly by genetic algorithms. The result will prove that our proposed method is much effective.

Keywords: Fuzzy logic control, low voltage ride through (LVRT), Doubly fed induction generator (DFIG), RSC and GSC, power systems faults

WSEAS Transactions on Power Systems, ISSN / E-ISSN: 1790-5060 / 2224-350X, Volume 10, 2015, Art. #15, pp. 135-144

Title of the Paper: Artificial Bee Colony Algorithm Based Maximum Power Point Tracking in Photovoltaic System System Using ABC Algorithm

Authors: A. S. Oshaba, E. S. Ali, S. M. Abd Elazim

Abstract: Maximum Power Point Tracking (MPPT) is used in Photovoltaic (PV) systems to maximize its output power. A new MPPT system has been proposed for PV-DC motor pump system by designing two PI controllers. The first one is used to reach MPPT by monitoring the voltage and current of the PV array and adjusting the duty cycle of the DC/ DC converter. The second PI controller is designed for speed control of DC series motor by setting the voltage fed to the DC series motor through another DC/ DC converter. The proposed design problem of MPPT and speed controller is formulated as an optimization problem which is solved by Artificial Bee Colony (ABC) to search for optimal parameters of PI controllers. Simulation results have shown the validity of the proposed technique in delivering MPPT to DC series motor pump system under atmospheric conditions and tracking the reference speed of DC series motor. Moreover, the performance of the proposed ABC algorithm is compared with Genetic Algorithm (GA) for different disturbances to prove its robustness.

Keywords: Photovoltaic System, Optimization Algorithm, Maximum Power Point Tracking, PI Controller, Speed Control, DC Series Motor Pump System

WSEAS Transactions on Power Systems, ISSN / E-ISSN: 1790-5060 / 2224-350X, Volume 10, 2015, Art. #14, pp. 123-134

Title of the Paper: Assessment of Optimal PID Tuning Controllers for Load Frequency Control

Authors: P. Dhanalakshmi, K. Mahadevan

Abstract: This paper presents two methods for designing the parameters of PID controller, the first is the Particle Swarm Optimization technique and the second is a Bacterial Foraging Optimization Algorithm. These two methods are used to search for optimal parameters of the controllers to minimize the performance index. A two area thermal system is considered for design and analysis. In each area LFC monitors the system frequency deviations and tie line power which gives the net change in area control error. If the ACE is made to zero, then both tie line power and frequency will be forced to zero. The superiority of the proposed approach has been demonstrated by comparing the results and is observed that it could be easily extended to other global optimization problems.

Keywords: LFC (Load Frequency Control), ACE (Area Control Error), PID (Proportional-Integral-Derivative), PSO (Particle Swarm Optimization), BFOA (Bacterial Foraging Optimization Algorithm)

WSEAS Transactions on Power Systems, ISSN / E-ISSN: 1790-5060 / 2224-350X, Volume 10, 2015, Art. #13, pp. 116-122

Title of the Paper: Imperialist Competitive Algorithm: A Novel Approach for Speed Control of Induction Motor Supplied by Wind Turbine

Authors: Ali E. S.

Abstract: This paper proposes the design of a Proportional Integral (PI) controller using Imperialist Competitive Algorithm (ICA) to control the speed of an Induction Motor (IM) fed from wind turbine. The wind turbine plays as a prime mover to a connected DC generator. Pulse Width Modulation (PWM) is used to get three phase AC voltage from the output of DC generator. The proposed design problem of speed controller is established as an optimization problem. ICA is adopted to search for optimal controller parameters by minimizing the time domain objective function. The behaviour of the proposed ICA has been estimated with the behaviour of the conventional Zeigler-Nichols (ZN) and Genetic Algorithm (GA) in order to prove the superior efficiency of the proposed ICA in tuning PI controller. Also, the behaviour of the proposed controller has been estimated with respect to the change of speed wind turbine and load torque. Simulation results confirm on the better performance of the optimized PI controller based on ICA in compare to optimized PI controller based on GA and conventional one over a wide range of operating conditions.

Keywords: Genetic Algorithm, Imperialist Competitive Algorithm, Induction Motor, Integral Time Absolute Error, Speed Control, Wind Turbine

WSEAS Transactions on Power Systems, ISSN / E-ISSN: 1790-5060 / 2224-350X, Volume 10, 2015, Art. #12, pp. 105-115

Title of the Paper: PLC-SCADA Based Supply Side Management in Deregulated Power Market

Authors: Vijaya Chandrakala K. R. M., Balamurugan S., Abhilash R., Adithya K., Krishna Kumar O., Balaji T. J.

Abstract: The deregulation of power industry is restructuring of rules of monopoly, hence bringing in more private players to sell or buy the electricity as a commodity. The power and price values are bid by the respective generation companies (GENCO’s) and distribution companies (DISCOM’s) through the electronic mode. There are various complex computing methods for determining the optimum price among which the power exchange curve method is discussed herewith. By plotting demand and supplier power characteristics curves, the intersection point, MCP (Market clearing price) can be determined. MCP calculation is one of the most important functions of a power pool operator. Its main objective is to maximize the Global welfare function where the generating companies and the consumers are benefited and unbiased. The MCP is calculated using MATLAB software and the winning bidders of the current market are found. The power obtained for the winning supplier then undergoes optimum scheduling for generation optimization namely, supply side management. The power optimization includes Unit Commitment (UC) and selected units to be committed undergo Economic Load Dispatch (ELD). For practical implacability, the supply side power management is implemented using Programmable Logic Controller (PLC) communicated through the Supervisory Control and Data Acquisition (SCADA) system.

Keywords: Deregulation, Market Clearing Price, Generating Companies, Distribution Companies, Programmable Logic Controller, Supervisory Control and Data Acquisition System

WSEAS Transactions on Power Systems, ISSN / E-ISSN: 1790-5060 / 2224-350X, Volume 10, 2015, Art. #11, pp. 97-104

Title of the Paper: Optimizing Weight Factors in Multi-Objective Simulated Annealing for Dynamic Economic/Emission Dispatch

Authors: Ziane Ismail, Benhamida Farid, Amel Graa

Abstract: This paper presents a Simulated Annealing Optimization to solve a Dynamic Economic/Emission Dispatch problem. In this work, the problem is formulated as a multi-objective one with two competing functions, namely economic cost and emission functions, subject to different constraints. The inequality constraints considered are the generating unit capacity limits while the equality constraint is generation-demand balance. To show the advantages of the proposed algorithm, it has been applied for solving multi-objective EELD problems in a 6-generators system considering NOx, SO2, and CO2 emission. This technique is compared with other techniques which reveals the superiority of the proposed approach and confirms its potential for solving other power systems problems.

Keywords: Economic dispatch, multi-objective optimization, weight factors, simulated annealing

WSEAS Transactions on Power Systems, ISSN / E-ISSN: 1790-5060 / 2224-350X, Volume 10, 2015, Art. #10, pp. 89-96

Title of the Paper: A Wavelet Based Data Compression Technique for Power Quality Events Classification

Authors: P. Kanirajan, V. Suresh Kumar

Abstract: This paper proposes a wavelet –based data compression for classification of PQ events. The Compression technique is performed through signal decomposition, signal reconstruction and according to the criterion of the maximum wavelet energy coefficients. To justify the proposed method, data are simulated under disturbances in which various power quality events which include voltage sag, swell, momentary interruptions and harmonics were simulated and used for testing the performance of various order and scale for daubechies and symlet functions. Simulation results indicate that the order 2 and scale 5 of wavelet functions offers superior compression performance compared to various other levels.

Keywords: Power Quality, wavelets, Multiresolution signal decompositions, data compression

WSEAS Transactions on Power Systems, ISSN / E-ISSN: 1790-5060 / 2224-350X, Volume 10, 2015, Art. #9, pp. 82-88

Title of the Paper: Harmonic Compensation Using On-Line Bacterial Foraging Optimization Based Three-Phase Active Power Filter

Authors: G. El-Saady, Abou-Hashima El-Sayed, E. A. Ebrahim, H. I. Abdul-Ghaffar

Abstract: The active power filter has gained much more attention because of its effective performance to mitigate the harmonics. This paper presents shunt active power filter (SAPF) controlled by PI controller to compensate the harmonics. Also, it introduces a new artificial intelligent technique called Bacterial Foraging Optimization to optimize the parameters of the PI-controller through on-line self-adaptive self-tuning algorithm. This robust control scheme of the system makes improvement in the behavior of the active filter to eliminate the harmonic currents which occurred by the nonlinear loads in the electric grid. The hysteresis non-linear current control method is used to generate the pulse gate required to drive PWM current-controlled voltage-source inverter of SAPF. Matlab/Simulink software package is used as a simulation to test and simulate the proposed system. Through the simulation results, it is observed that the response of the PI controller based on-line bacteria foraging optimization is quite satisfactory.

Keywords: Active Power Filter, PI controller, Bacterial Foraging Optimization, Hysteresis Current Control

WSEAS Transactions on Power Systems, ISSN / E-ISSN: 1790-5060 / 2224-350X, Volume 10, 2015, Art. #8, pp. 73-81

Title of the Paper: Voltage and Real Power Loss Analysis Incorporating CE-SSSC with VS-SVC Combination through Fruit Fly Optimization

Authors: L. Jebaraj, C. Christober Asir Rajan, Irisappane Soubache

Abstract: This paper focuses an application of Fruit fly Optimization Algorithm based voltage stability enhancement and minimization of real power loss incorporating the combination of Series – Shunt flexible AC transmission system (FACTS) controllers named as Static Synchronous Series Compensator (SSSC) combined with Static Var Compensator (SVC). A new circuit element model of SSSC (CE-SSSC) with variable susceptance model of SVC (VS-SVC) is utilized to control the line power flows and bus voltage magnitudes respectively for real power loss minimization and voltage stability limit improvement. The line quality proximity index (LQP) is used to assess the voltage stability of a power system. The values of Voltage profile improvement, real power loss minimization and the location and size of FACTS devices were optimized Fruit fly Optimization Algorithm (FOA). The results are obtained from three power system test cases (IEEE 14 bus, IEEE 30 bus, IEEE 57 bus) and one practical case such as Indian Utility Neyveli Thermal Power Station (IUNTPS) 23 bus system and compare with other leading evolutionary techniques such as Shuffled Frog Leaping Algorithm (SFLA), Differential Evolution (DE), Particle Swarm Optimization (PSO) and Genetic Algorithm (GA) under three different cases such as normal loading, critical loading and single line outage conditions.

Keywords: Fruit Fly Optimization Algorithm, Voltage Stability, Static Var Compensator, Line Stability Index, FACTS Devices, Load Flow

WSEAS Transactions on Power Systems, ISSN / E-ISSN: 1790-5060 / 2224-350X, Volume 10, 2015, Art. #7, pp. 55-72

Title of the Paper: THD Improvement of a PWM Cascade Multilevel Power Inverters Using Genetic Algorithms as Optimization Method

Authors: Jorge Luis Diaz Rodriguez, Luis David Pabon, Aldo Pardo Garcia

Abstract: This paper presents an optimization of the electric power quality by designing a 9 steps multilevel power inverter, which adopts a multi-PWM optimized using genetic algorithms (GA), and minimizing Total Harmonic Distortion (THD) of the first 50 harmonics to about 0%. This optimization is considered an alternative technique because it reduces the expression used to quantify TDH numerically. Particularly for the 9 steps multilevel wave form, it reduces the number of power on-and-off angles as well as the position within the levels of the first quarter-wave modulation. The research involved developing a prototype for experimental verification.

Keywords: Multilevel inverter, total harmonic distortion, genetic algorithm, PWM

WSEAS Transactions on Power Systems, ISSN / E-ISSN: 1790-5060 / 2224-350X, Volume 10, 2015, Art. #6, pp. 46-54

Title of the Paper: Load Frequency Control in Two Area Multi Units Interconnected Power System Using Multi Objective Genetic Algorithm

Authors: V. Jeyalakshmi, P. Subburaj

Abstract: In this paper, load frequency control in two-area multi- units interconnected hydro thermal power system has been investigated. When an interconnected power system is subjected to heavy load disturbances, the system frequency and tie-line power flow are disturbed which leads to system instability. To stabilize the system frequency oscillations and tie - line power flow variations, a PID controller in coordination with Thyristor controlled phase shifter (TCPS) is proposed in this work. The parameters of PID controller and TCPS controller is tuned by using the proposed Global Ranking Multi objective Genetic algorithm (GRMOGA). The objective of this work is to improve the dynamic performance of the interconnected power system under heavy load disturbances. By the application of the proposed algorithm, the optimal gain values of the controllers are selected. Simulation studies are carried out by applying those optimal parameters values in the developed model and to show the effective performance of the proposed controller comparative analysis has been made with conventional PID and single objective GA PID controller.

Keywords: Load frequency control, Hydrothermal power system, PID controller, TCPS controller, Genetic algorithm, Multi objective optimization

WSEAS Transactions on Power Systems, ISSN / E-ISSN: 1790-5060 / 2224-350X, Volume 10, 2015, Art. #5, pp. 35-45

Title of the Paper: Design and Construction of a System for Wirelessly Charging the Battery of a Robot

Authors: Mohamed Zied Chaari, Hamadi Ghariani, Mongi Lahiani

Abstract: The purpose of this paper is to develop a check the technique designed for charging battery of robot Crawler during the pipeline inspection. The wireless energy transmission mechanism is composed of a transmitter, circular guided wave and a receiver. The system based on the principle of transfer of microwave energy inside- through - the pipeline. The idea is to use the pipeline as a waveguide to minimize the attenuation of energy as well as to maximize the power recovered to the level of horn conical antenna. We present and we studied the converting RF energy into DC electrical energy. This article represents an update on application areas and principles used and to show the utility of pipeline for transfer energy.

Keywords: Robot Crawler, Magnetron, Horn antennas, circular waveguide, Pipeline, RF/DC Convertor

WSEAS Transactions on Power Systems, ISSN / E-ISSN: 1790-5060 / 2224-350X, Volume 10, 2015, Art. #4, pp. 27-34

Title of the Paper: Power Quality Improvement in Wind Energy Conversion System of Grid Interfacing Inverter Using Hysteresis Band Current Controller

Authors: Bhavna Jain, Shailendra Jain, R. K. Nema

Abstract: Recently renewable energy resources especially wind power integration has been extensively increased in the electric power distribution system. To exploit renewable energy sources more effectively, grid connection of renewable energy sources is done through power electronics interfaces. But it causes problem of voltage fluctuation and harmonic distortion. In this paper, an appropriate model of wind energy conversion system is presented and simulation techniques are discussed for studying power quality problems due to the voltage fluctuation and harmonic distortion in the system. A hysteresis band current control strategy of grid side power converter is presented for grid synchronisation. The proposed power electronics interface and control technique calculates compensating signal and injects it at point of common coupling (PCC). Generation of gate signal of voltage source inverter (VSI) is done through hysteresis band current controller (HBCC). Matlab/simulink is used to simulate wind energy conversion system and control strategy implemented using HBCC to ensure high quality of the injected power and grid synchronization.

Keywords: Hysteresis band current controller, phase locked loop (PLL), point of common coupling, power quality, wind energy conversion system (WECS)

WSEAS Transactions on Power Systems, ISSN / E-ISSN: 1790-5060 / 2224-350X, Volume 10, 2015, Art. #3, pp. 20-26

Title of the Paper: Analysis of the Power Quality Using Intelligent Techniques

Authors: Victor Garrido Arevalo, Jorge Luis Diaz R., Aldo Pardo Garcia

Abstract: In this work, the mathematical modelling and simulation of some of the phenomena that affect the power quality is presented, Discrete Wavelet Transform is applied to obtain characteristic patterns of each signal. With these patterns several intelligent classifiers (neural networks and support vector machine) are trained and determine which of these they have better results in terms of predicting the class to which belongs each of said patterns. Knowing the energy distributions of the coefficients of detail, a general power quality index is formulated and compared with the existing ones.

Keywords: Power Quality, Harmonics, Sag, Swell, Flicker, Wavelet, Neural Networks, Support Vector Machine

WSEAS Transactions on Power Systems, ISSN / E-ISSN: 1790-5060 / 2224-350X, Volume 10, 2015, Art. #2, pp. 13-19

Title of the Paper: A Review and Evaluation of Current Wind Power Prediction Technologies

Authors: Sumit Saroha, S. K. Aggarwal

Abstract: The wind power prediction plays an essential role in operation, planning, taking part in open access and real time balancing of power system. Various forecasting methodologies have been proposed in number of research papers since last few decades. Therefore, on the basis of available literature, this review analyses new and current developments in the area of wind power & prediction of its derivatives (speed or direction) and compared in the form of comparative tables concerning the accuracy with taken care of variables to be predicted, time horizon, specific application area, data pre-processing, input data selection techniques, data used and various neural network techniques with their structure. The main focus of this review is to facilitate the various issues related to wind power forecasting techniques, emphasis on reduction of complexity of forecasting problem with increase in forecasting accuracy for different time span. The purpose of this research article is to motivate the power system researchers for designing new highly accurate online/offline models with concern to different issues regarding wind power resulting in secure reliable power system operation & better utilisation of energy resources. It has been observed that from a comparative forecasting accuracy analysis, hybrid models presented more accurate results as compared to other models.

Keywords: Wind power forecasting, time series, artificial intelligent techniques, accuracy criteria

WSEAS Transactions on Power Systems, ISSN / E-ISSN: 1790-5060 / 2224-350X, Volume 10, 2015, Art. #1, pp. 1-12