Class 5 flexible aluminum conductors are not common in cable manufacturing industry due to insufficient study on cable joints and connectors. The table of ampacities for aluminum conductors at 110 °C in AS/NZS3008.1.1 standards are also not available as a reference guide for electrical system designers that restricts the installation of aluminum low voltage (LV) cabling system to operate at 90 °C of conductor maximum operating temperature where 110 °C cables are permitted in Australia. In this paper, the cable ampacities of various LV Class 5 flexible aluminum cables at maximum operating temperature of 110 °C are calculated using IEC60287 and AS/NZ3008.1.1 standards. The calculated ampacities from the formula presented in clause 4.4. of AS/NZS3008.1.1 are verified by using the 6kA inductive current generator to determine the suitability for use. The joint temperature between cable and shear bolt mechanical connectors are simultaneoulsy simulated using the calculated ampacities to determine the suitability of mechanical shear bolt connectors when the coefficient of thermal expansion of material is considered. The observed differences between the calculated and measured values demonstrate the relevance of formula used in determining the current ampacity at 110 °C conductor temperature in free air.
EPR-insulated cables for distribution power network are not commonly used in Australia. This is due to the higher DDF of common EPR cables when compared with XLPE that contributes to the power loss and economics in transmitting electricity. This led to the development of EPR called TR-EPR with significantly lower DDF and uses silane curing process to address concerns about cost-effectiveness. The thermal behavior of low DDF silane cure TR-EPR is investigated for 30 months of exposure to the maximum operating temperature of material. The physical changes in the samples throughout the long-term aging are examined to create an opportunity to model the expected life cycle of TR-EPR cable under thermal stress. The cross-linking characteristics of TR-EPR cable are also examined by ambient curing that simulates the storage condition for unused cable and by cable heating process that simulates the condition when the cable is energized. The results are tabulated for a better understanding of the time for the material to cross-link at various conditions. The improved partial discharge values after cross-linking are also presented.
Renewable energy have the potential to generate electricity cleanly without pollution and a lesser dependence of resources for this production of electric power by these systems sources such as solar, wind, hydro, geothermal and biomass instead anti-environmental conventional systems such as gas, coal and oil is a remarkable idea but not frequent in Algeria. Our research focuses on the study of a hybrid energy system (Photovoltaic-Wind), connected to the Electrical Network 220 kV and this by tracking the maximum power point (MPPT) for two energy sources. For this, methods based on optimization algorithms were used side PV array and Wind turbine. With regard to the wind turbine, optimization was based on an analytical approach method. The Matlab/Simulink is used for simulated power output from Hybrid System, power delivered to or from grid and phase voltage of the inverter leg
p class="Abstract">In this work, a 24-sector direct power control (24-sector DPC) of a doubly-fed induction generator (DFIG) based dual-rotor wind turbine (DRWT) is studied. The major disadvantage of the 24-DPC control is the steady-state ripples in reactive and active powers. The use of 24 sectors of rotor flux, a feedforward neural network (FNN) algorithm is proposed to improve traditional 24-sector DPC performance and minimize significantly harmonic distortion (THD) of stator current and reactive/active power ripple. The proposed method is modeled and simulated by using MATLAB/Simulink software under different tests and compared with conventional 24-sector DPC.</p
In this paper, analysis and modeling of a single-phase H-bridge forty-one level inverter are con sidered. The control of proposed inverter by equal-phase and half-height methods is implemented. MATLAB/Simulink environments are used to simulate the model an d show obtained results of waveforms with FFT analysis. Eventually, the total harmonic distortion obtained for each level with the two methods is presented, comparatively, for a comparison.
In this paper an attempt has been made to solve the profit based unit commitment problem (PBUC) using pre-prepared power demand (PPD) table with an artificial bee colony (ABC) algorithm. The PPD-ABC algorithm appears to be a robust and reliable optimization algorithm for the solution of PBUC problem. The profit based unit commitment problem is considered as a stochastic optimization problem in which the objective is to maximize their own profit and the decisions are needed to satisfy the standard operating constraints. The PBUC problem is solved by the proposed methodology in two stages. In the first step, the unit commitment scheduling is performed by considering the pre-prepared power demand (PPD) table and then the problem of fuel cost and revenue function is solved using ABC Algorithm. The PPD table suggests the operator to decide the units to be put into generation there by reducing the complexity of the problem. The proposed approach is demonstrated on 10 units 24 hour and 50 units 24 hour test systems and numerical results are tabulated. Simulation result shows that this approach effectively maximizes the GENCO’s profit than those obtained by other optimizing methods.
The distributed generation (DG) refers to the use of the nearby units of small generation or in the sleefelzentres. Revisions have shown that unfitting choice of the position and scope of the DG can lead to bigger system sufferers than DG's sufferers. Public services are already available before the high loss of energy loss and of the mediocre voltage profile, in particular developing countries cannot tolerate any increase in losses. From optimal allocation, public services in the reduction of system losses improve tension adjustment and improve delivery reliability. This article aims to minimalize the annual system's annual loss through the appropriate positioning and size of the DG units. The artificials bee colony (ABC) of EPA are inspired by the behavior of the API feeding, this method is incredibly conventional, a stroke or a peoplated stochastic optimization algorithm to meet the solution of the specified problem. At MATLAB, a probabilistic approach is simulated to reach the target indicates that the size of the DGs to be installed to reduce almost the same loss as a percentage that the situation in which the load power is considered constant.
This paper presents the design and analysis of a novel polygon connected autotransformer based 30-phase ac-dc converter which supplies Direct Torque Controlled Induction Motor Drives (DTCIMD’s) in order to have better power quality conditions at the point of common coupling. The proposed converter output voltage is accomplished via three paralleled 10- pulse ac-dc converters each of them consisting of 5-phase diode bridge rectifier. An autotransformer is designed to supply the rectifiers. The proposed converter requires only three inter-phase transformers in the dc link that leads to the reduced kilovolt ampere rating, size, weight, and cost of the proposed rectifier. The design procedure of magnetics is in a way such that makes it suitable for retrofit applications where a six-pulse diode bridge rectifier is being utilized. The aforementioned structure improves power quality criteria at ac mains and makes them consistent with the IEEE-519 standard requirements for varying loads. Furthermore, near unity power factor is obtained for a wide range of DTCIMD operation. A comparison is made between 6-pulse and proposed converters from view point of power quality indices. Results show that input current Total Harmonic Distortion (THD) is less than 3% for the proposed topology at variable loads.
Renewable energy based microgrids have main challenges of maintaining its frequency-voltage characteristics and system becomes more complex when they are interconnected. These sources being intermittent in nature need to be supported by other resources like diesel/biogas such that at time of small variation in load or natural sources (wind/solar), power requirement is met through support provided by diesel/biogas-based system. Also, the controller should be fast enough to minimize the changes such that system reaches steady state. In this paper, renewable based rural microgrid consisting of wind, solar and biogas is modeled and interconnected through low voltage AC (LVAC) line. Also, one of the microgrid modeled is connected to the main grid as well as drawing power from the other microgrid. Control approach have been developed in such a way that whenever there is disturbance in the system due to increase/decrease in load or input to the renewable energy sources the biogas-based system of individual microgrid increases/decreases its generation to support the system requirement. No extra power is drawn either from the LVAC network or main grid as desired. modeling of system and its dynamic Study has been carried out in MATLAB/Simulink.
Generally, AC-AC converters are implemented using thyristors. These converters generate harmonics and have a low power factor. To eliminate these problems matrix converters (MC) are become used as AC-AC converter. Matrix converters have the capability of being used as frequency changer, rectifier, inverter and chopper. In this work, it is proposed to achieve the desired output of AC-AC Boost converter using single phase matrix converter (SPMC). The operation of single-phase AC-AC boost converter using MC is studied in this paper. The output voltage of this boost converter is higher than the AC input supply voltage. insulated gate bipolar transistors (IGBTs) are used as the switching elements in the SPMC power circuit. Sinusoidal Pulse width modulation (SPWM) technique is applied to generate switching signals to obtain the output voltage. The model of the matrix converter is constructed in MATLAB/Simulink programming software package. The behavior of SPMC is simulated with various switching frequencies. The simulation results together with harmonic spectrum and total harmonic distortion (THD) values are presented. Successful operation of boost SPMC is achieved.
The developments in power quality are fast and difficult to predict. The majority of power quality issues experienced by industrial customers can be attributed to momentary interruptions, voltage sags or swells, transients, harmonic distortion, electrical noise, and flickering lights, among others. A new device may be invented tomorrow solving power quality problems. The FACTS devices could provide fast control of active and reactive power through a transmission line. The unified power-flow controller (UPFC) is a member of the FACTS family with very attractive features. This device can independently control many parameters, so it is the combination of the properties of a static synchronous compensator (STATCOM) and static synchronous series compensator (SSSC).The performance of AC Transmission system with Unified power flow controller under various power quality problems analysis described. The proposed system is formulated and research work is done by wavelet multi resolution analysis using Bior1.5 mother wavelet with MATLAB/SIMULINK software. It is observed that the effectiveness of AC power transmission through Unified power flow controller under power quality problems of sag, swell, transient, temporary faults and capacitive switching.
This paper suggested a new contribution of three phase AC to AC matrix converter MC via fuzzy logic controller FLC to enhance the whole system. However, the weakness of matrix converter is that the input- output voltage transfer is control to 87% for input and output waveform. Also, matrix converter is more sensitive to the trouble of input voltage which deteriorates the system performance. To overcome these problems, and to improve the efficiency of system, FLC with matrix converter is proposed to minimize the sensitivity to the load, and to increase voltage transfer. In this paper the currents a,b,c are converted to alpha and beta current via Clarke transformation . In this method two FLC are used. The error (between alpha current and reference current) (e) and the change of this error (de) will apply to first FLC. The output of FLC is actual alpha current. In the other hand, the error of beta current and the change of error are also passes through the second FLC to produce the actual beta current. The actual alpha and beta current is converted to direct and quadrature d-q current by park transformation. The d-q current is converted to (a, b, c) out currents by inverse park transformation, the results of this method express that the matrix converter with FLC is more capable, high accuracy with better efficiency as compared with conventional matrix converter system.
div data-canvas-width="162.73488208022576">Numerical analysis of MHD casson fluid flow over an exponentially accelerated vertical plate in embedded porous medium with ramped wall temperature and ramped surface concentration has investigated in the current investigation. The flow governing dimensional velocity, temperature and concentration differential equations are converted into non dimensional form by using non-dimensional variables. Numerical solutions to the converted equations are obtained by finite element method. The results are presented graphically and in tabular form for various controlling parameters. In order to highlig ht the validity and accuracy of our present method, we have compared our results with the results obtained earlier. A very good validation of the present numerical results has been achieved
div data-canvas-width="75.53283108244308">A simulation model for integrated waste biomass gasification with cogeneration heat and power has been developed using Aspen Plus. The model can be used as a predictive tool for optimization of the gasifier performance. The system has been modeled in four stages. Firstly, moisture content of biomass is reduced. Secondly biomass is decomposed into its elements by specifying yield distribution. Then gasification reactions have been modeled using Gibbs free energy minimization approach. Finally, power is generated through the internal combustion engine as well as heat recovery system generator. In simulation study, the operating parameters like temperature, equivalence ratio (ER) and biomass moisture content are varied over wide range and their effect on syngas composition, low heating value (LHV) and electrical efficiency (EE) are investigated. Overally, increasing temperature and decreasing ER and MC lead to improvement of the gasification performance. However, for maximum electrical efficiency, it is important to find the optimal values of operating conditions.
The optimum temperature, ER and MC of the down draft gasifier for timber and wood waste are 800 ̊C, 0.2- 0.3 and 5%. At such optimum conditions, CO and H
2 reach to the highest production and LHV and EE are around 7.064 MJ Nm-3 and 45%, respectively.</div
Earlier, a simple dynamic equivalent for a power system external area containing a group of coherent generators was proposed in the literature. This equivalent is based on a new concept of decomposition of generators and a two-level generator aggregation. With the knowledge of only the passive network model of the external area and the total inertia constant of all the generators in this area, the parameters of this equivalent are determinable from a set of measurement data taken solely at a set of boundary buses which separates this area from the rest of the system. The proposed equivalent, therefore, does not require any measurement data at the external area generators. This is an important feature of this equivalent. In this paper, the results of a comparative study on the performance of this dynamic equivalent aggregation with the new inertial aggregation in terms of accuracy are presented. The three test systems that were considered in this comparative investigation are the New England 39-bus 10-generator system, the IEEE 162-bus 17-generator system and the IEEE 145-bus 50-generator system. Full Text: PDF
The present work deals with the economic rescheduling of the generation in an hour-ahead electricity market. The schedules of various generators in a power system have been optimizing according to active power demand bids by various load buses. In this work, various aspects of power system such as congestion management, voltage stabilization and loss minimization have also taken into consideration for the achievement of the goal. The Interior Point (IP) based Optimal Power Flow (OPF) methodology has been used to obtain the optimal generation schedule for economic system operation. The IP based OPF methodology has been tested on a modified IEEE-30 bus system. The obtained test results shows that not only the generation cost is reduced also the performance of power system has been improved using proposed methodology.
The modern power system is equipped with protection system based on advanced technology through the use of digital multifunction relay, control system and intelligent selectivity, whose purpose is to ensure maximum security and service continuity of protection relay in the presence of various fault currents. Distance protection is an important protection required in high voltage transmission lines. In this paper, experimental platform tests have been performed and proposed for setting and evaluation the performances of distance protection named Micom P442 installed in Biskra-Batna of the Algerian transmission power system. The performances of the distance protection have been evaluated under various short circuits. In this study, experimental result based single phase fault to ground is analysed and discussed. Experimental results based on the proposed platform tests in terms of precision in detecting faults at various locations and trigger times confirm the efficiency and particularity of the proposed experimental platform tests.
In this work Amplified Brain Storm Optimization (ABS) algorithm and Quantum based Brain Storm (QBS) Optimization Algorithm is used for solving optimal reactive power problem. In the projected amplified Brain storm optimization algorithm Hamiltonian cycle has been applied to improve the search abilities and also to avoid of trap in local optimal solution. A node is arbitrarily chosen from the graph as the preliminary point to form a Hamiltonian cycle. At generation t and t+1, L<sub>t</sub> and L<sub>t</sub><sub>+1</sub> are the length of Hamiltonian cycle correspondingly. In the QBS algorithm a Quantum state of an idea is illustrated by a wave function as an alternative of the position modernized only in Brain storm optimization algorithm. Monte Carlo simulation method is used, to measure the position for each idea from the quantum state to the traditional one. Proposed Amplified Brain Storm Optimization (ABS) algorithm and Quantum based Brain Storm (QBS) Optimization Algorithm has been tested in standard IEEE 57 bus test system and simulation results show the projected algorithms reduced the real power loss effectively.
In this paper, the transmission loss allocation problem has been studied and a new method for loss allocation in pool electricity markets has been proposed. To do that, at first using a transmission line loss equations respect to bus injected currents, the share of each bus from the mentioned transmission line losses has been determined. Then, this method has been applied to the total network transmission lines and the share of each bus from the total losses has been acquired. The proposed method is based on the main network relations and no any simplifying suppose has been used. Finally, the proposed method is studied on a typical network.
In this paper, a new method is proposed to optimal distributed generation allocation for stability enhancement in radial distribution networks. Voltage stability is related with stable load and acceptable voltage in all buses of system. According to the time spectrum of the incident of the phenomena the instability is divided into steady state and transient voltage instability. The analysis is accomplished using a steady state voltage stability index which can be evaluated at each node of the distribution system. Different optimal locations and capacities are used to check this effect. The location of DG is more important in comparison with the capacities and has the main effect on the network voltage stability. Effects of capacity and location on increasing steady state voltage stability in radial distribution networks are evaluated through Imperialist Competitive Algorithm (ICA) and at the end the results are compared to particle swarm optimization and genetic algorithm on the terms of speed, accuracy and convergence. Full Text: PDF
The off-grid hybrid renewable energy generation system has lesser cost of energy with higher reliability when compared with solar Photovoltaic (PV) or wind energy system individually. The optimization design is worked out by reducing the Unit Cost Of Energy (UCOE) for different case studies and comparing the outcomes obtained by the use of HOMER-Pro (hybrid optimization model of electric renewable) software. The optimal cash flow analysis of hybrid energy system is based on the load patterns is discussed, solar irradiance (kW/m2) of site at proper latitude and longitude, wind speed and price of diesel, which is collected from a remote village in Khurda District, Odisha in India. Moreover, the optimization and sensitivity results of the system are find out by varying the input parameters like solar radiation, wind speed etc.
The off-grid hybrid renewable energy generation system has lesser cost of energy with higher reliability when compared with solar photovoltaic (PV) or wind energy system individually. The optimization design is worked out by reducing the unit cost of energy (UCOE) for different case studies and comparing the outcomes obtained by the use of HOMER-Pro (Hybrid Optimization Model of Electric Renewable) software. The optimal cash flow analysis of hybrid energy system is based on the load patterns is discussed, solar irradiance (kW/m2) of site at proper latitude and longitude, wind speed and price of diesel, which is collected from a remote village in Khurda District, Odisha in India. Moreover, the optimization and sensitivity results of the system are find out by varying the input parameters like solar radiation, wind speed etc.
p> In this paper, supervisor control for stand-alone hybrid power system to supply energy to resistance load is presented. The hybrid system is used to produce energy withoutinterruption and it consists of a photovoltaic generator (PV), and a battery bank. PV system work in parallel via DC/DC converter and the battery bank is used to store the excess of energy. The mathematical model topology, the identification of each subsystem and the control supervision of theglobal system are the contribution of this paper. Obtained results under Matlab/Simulink presented and discussed. </p
Power systems operation becomes more important as the load demand increases all over the world. This rapid increase in load demand forces power systems to operate near critical limits due to economical and environmental constraints. The objective in power systems operation is to serve energy with acceptable voltage and frequency to consumers at minimum cost. This paper studies the important power system phenomenon and voltage stability by using continuation power flow method and steady-state modeling of Static Synchronous Compensator (STATCOM) and Thyristor Controlled Series Capacitor (TCSC) for continuation power flow studies has been represented and discussed in details.also this paper studies voltage stability by using continuation power flow method and Comparison between performance of TCSC and STATCOM for improve voltage stability has been done. Case studies are carried on 9 bus network. Simulation is done with PSAT in MATLAB. Power Flow and Continuation Power Flow is was implemented using Newton-Raphson method. Simulation results show the proper performance of TCSC and STATCOM to improve voltage control and power flows on the lines and significantly increase the loadability margin of power systems. Full Text: PDF
p>A novel approach is proposed in this paper for optimal placement of DG units in reconfigured distribution system with the aim of reduction of real power losses while satisfying operating constraints. The proposed analytical method for optimal DG placement is developed based on a new mathematical formulation. Type-I and type-II DG units are used here. The results of the proposed technique are validated on IEEE 69 bus distribution system. The level of DG penetration is also considered in a range of 0–50% of total system load. A novel index is also proposed which incorporates level of DG penetration and percentage reduction in real power losses. The results are promising when compared with recently proposed algorithms.</p
Fast band power measurement technique used for measuring band power in wireless fidelity (Wi-Fi) devices. The difficulty during testing the band power is burst mode transmission takes longer time to measure. A test jig or specialized tool required is costly, which allows continuous mode of transmission for power measurement. The delivered average power by a Wi-Fi device depends upon the data rate which can also vary during time. The procedure proposed hereby developed using a spectrum analyzer to measure band power in the burst mode, in order to ensure repeatable results and optimized to enable fast measurements at low cost, less time and above 90% accurate.
A modified adaptive neuro-fuzzy inference system sliding mode control (ANFIS-SMC) by using two-level space vector pulse width modulation (SVPWM) for doubly fed induction generator (DFIG) is proposed in this article. ANFIS-SMC with SVPWM strategy improves the basic SMC performances, which features low stator active and reactive power and also minimize the total distortion harmonic (THD) of stator current. The computer simulation results, in Matlab, demonstrate the effectiveness of the proposed control strategy which improves the performance of the DFIG.
span lang="EN-US">In recent years, huge developments in wind energy production and meet consumer demand. Numerous researchers have focused on maximum energy generation techniques for the wind system. The main reason for this work is to compare the different smart controllers for the maximum power generation techniques in the wind system. In this article, we developed and modeled a 250-watt wind power system in a MATLAB environment and simulated it in different weather conditions. Based on the simulation results, two intelligent controllers, such as fuzzy and ANFIS, were proposed and compared to obtain the maximum energy generation techniques in the wind system. Finally, the optimal smart controller was chosen based on performance.</span
Not only is the theoretical calculation of the amount of solar radiation but also the characteristics of the light so significant in deciding the spectral sensitivity of the PV modules. The amount of radiation reaching on the earth depends on many atmospheric parameters such as wavelength and air mass. Spectral 2 is a model that calculates the amount of radiation for any region depending on the wavelength and atmospheric parameters. There are no theoretical and experimental studies on this subject in Turkey until now. In this study, the amounts of radiation coming to the surface having horizontal and different tilt angles were calculated for Mugla and Ankara. Due to the different climatic characteristics of Mugla and Ankara, the amount of radiation varies. According to the results, in winter and autumn, the amount of radiation which comes to Ankara and Mugla, is different each other. Due to the different climatical and geographical characteristics of Mugla and Ankara, the amount of radiation varies. The model, which is used in this study, due to atmospheric effects that have, is more comprehensive than any other empirical models made in Turkey.
p>This paper examines the role of magnetic field on fully developed natural convection flow in an annulus due to symmetric of surfaces. The transport equations concerned with the model under consideration are rendered non-dimensional and transformed into the ordinary differential equation using Laplace transform technique. The solution obtained is then transformed to time domain using the Riemann-sum approximation approach. The governing equations are also solved using implicit finite difference method so as to establish the accuracy of the Riemann-sum approximation approach at transient as well as at steady state solution. The solutions obtained are graphically represented and the effects of pertinent parameters on the flow formation are investigated in detail. The Hartmann number (M), is seen to have a retarding effect on the velocity, skin-frictions and the mass flow rate. Also, skin-friction at both surfaces and the mass flow rate within the annulus are found to be directly proportional to the radii ratio (λ).</p
In this work, a modern algorithm by hybrid genetic algorithm and ant colony algorithm is designed to placement and then simulated to determine the amount of reactive power by D-STATCOM. Also this method will be able to minimize the power system losses that contain power loss in transmission lines. Furthermore, in this design a IEEE 30-bus model depicted and three D-STATCOM are located in this system according to Economic Considerations. The optimal placement of each D-STATCOM is computed by the ant colony algorithm. In order to optimize placement for each D-STATCOM, two groups of ant are selected, which respectively located in near nest and far from the nest. Moreover, for every output simulation of D-STATCOM that is used to produce or absorb of reactive power, a genetic algorithm to minimizing the total network losses is applied. Finally, the result of this simulation shows net losses reduction about 150% that it verifies the new algorithm performance.
p> In this paper, a single-phase PV inverter applying a dual boost converter circuit inverter is proposed for photovoltaic (PV) generation system and PV grid connected system. This system is designed to improve integration of a Single phase inverter with Photovoltaic panel. The DC 24V is converted into to 86V DC and then 86V DC to 312V DC. The 312 V DC is then successfully inverted to AC 220V. Hence solar energy is powerfully converted into electrical energy for fulfilling the necessities of the home load, or to link with the grid. Matlab Simulation software was used for simulation of the circuit and outcome are presented in this paper. </p
Wind energy and solar energy are the prime energy sources which are being utilized for renewal energy. The performance of a photovoltaic (PV) array for solar energy is affected by temperature, irradiation, shading, and array configuration. Often, the PV arrays are shadowed, completely or partially, by the passing clouds, neighboring buildings and towers, trees, and utility and telephone poles. Under partially shaded conditions, the PV characteristics are more complex with multiple peaks, hence, it is very important to understand and predict the MPP under PSC in order to extract the maximum possible power. This paper presents the development of PV array simulator for studying the I–V and P–V characteristics of a PV array under a partial shading condition. It can also be used for developing and evaluating new maximum power point tracking techniques, for PV array with partially shaded conditions. It is observed that, for a given number of PV modules, the array configuration significantly affects the maximum available power under partially shaded conditions. This is another aspect to which the developed tool can be applied. The model has been experimentally validated and the usefulness of this research is highlighted with the help of several illustrations.
Wind energy and solar energy are the prime energy sources which are being utilized for renewal energy. The performance of a photovoltaic (PV) array for solar energy is affected by temperature, irradiation, shading, and array configuration. Often, the PV arrays are shadowed, completely or partially, by the passing clouds, neighboring buildings and towers, trees, and utility and telephone poles. Under partially shaded conditions, the PV characteristics are more complex with multiple peaks, hence, it is very important to understand and predict the MPP under PSC in order to extract the maximum possible power. This paper presents the development of PV array simulator for studying the I–V and P–V characteristics of a PV array under a partial shading condition. It can also be used for developing and evaluating new maximum power point tracking techniques, for PV array with partially shaded conditions. It is observed that, for a given number of PV modules, the array configuration significantly affects the maximum available power under partially shaded conditions. This is another aspect to which the developed tool can be applied. The model has been experimentally validated and the usefulness of this research is highlighted with the help of several illustrations
Design and simulation of a simple power electronic interface for grid-connected PV array has been proposed using boost converter and line-commutated inverter with maximum power point tracking (MPPT) controller. The output of PV array varies with irradiation, and hence the duty cycle of the PI controller is adjusted automatically to supply a constant DC voltage to the inverter circuit, the output of which is directly connected to the grid. The MPPT controller extracts maximum power from the solar array and feeds it to the single-phase utility grid. The proposed scheme has been modeled in the MATLAB 7.1 software and the complete system has been simulated for open loop and closed loop configurations. The active power fed to the grid is taken for different firing angles in open loop mode and the firing angle for maximum power has been determined. This is compared with the firing angle obtained from the closed loop mode and found that both results agree with each other.
In India Electrical Energy is generated mainly Coal based Thermal Power stations and hydro Electric Power Stations. The main aim of power generating company is to provide good quality and reliable power to consumers at minimum cost. The problem of Combined Economic and Emission Dispatch deals with the minimization of both fuel cost and emission of pollutants such as oxides of Nitrogen and Oxides of Sulphur. In our power system the emission is major problem created that’s why in now a days we move from green energy source or renewable energy such as Sunlight, Wind, Tides, Wave, and Geothermal Heat Energy. The Emission constrained Economic Dispatch problem treats the emission limit as an additional constraint and optimizes the fuel cost. In this paper we optimizes the Combined Economic and Emission Dispatch problem by using two different optimization method such as Artificial Bee Colony (ABC) and Genetic Algorithm (GA).The proposed ABC Algorithm has been successfully implemented is to IEEE 30 bus and Indian Utility sixty two Bus System The simulation result are compare and found the effective algorithm for Combined Economic and Emission Dispatch problem.
p>Reliability worth assessment is a primary concern in planning and designing of electrical distribution systems those operate in an economic manner with minimal interruption of electric supply to customer loads. Renewable energy sources (RES) based Distributed Generation (DG) units can be forecasted to penetrate in distribution networks due to advancement in their technology. The assessment of reliability worth of DG enhanced distribution networks is a relatively new research area. This paper proposes a methodology that can be used to analyze the reliability of active distribution systems (DG enhanced distribution system) and can be applied in preliminary planning studies to compute the reliability indices and statistics. The reliability assessment in this work is carried out with analytical approach applied on a test system and simulated results validate that installation of distributed generators can improve the distribution system reliability considerably.</p
Volume effect on breakdown voltage is well known in high voltage engineering. The breakdown voltage behavior of liquid nitrogen depending on a high field volume had been quantitatively described for gap lengths up to 20 mm. Breakdown curves for longer gap lengths up to 96 mm derived from measurements with a facility “Fatelini 2” show oscillations and partly low withstand voltages. Electrostatic field calculation for such long gaps shows remarkable high field volume differences between a model for ideal sphere and models including fixation rods. Calculation for the used setup does not show monotonically increasing high field volume depending on gap length but a maximum around 60 mm which can explain the special breakdown behavior in a “mid range” gap length. Further high field calculations were done for not yet used setups in order to make considerations, e.g. for the influence of cryostat material or diameter.
We consider in this paper the problem of controlling an arbitrary linear delayed system with saturating input and output. We study the stability of such a system in closed-loop with a given saturating regulator. Using inputoutput stability tools, we formulated sufficient conditions ensuring global asymptotic stability.
We consider in this paper the problem of controlling an arbitrary linear delayed system with saturating input and output. We study the stability of such a system in closed-loop with a given saturating regulator. Using input-output stability tools, we formulated sufficient conditions ensuring global asymptotic stability.
Electricity is the basic need of today’s scenario. In the 21st generation, growth and development is totally dependent on electricity. Thus, measurement of consumption of electricity becomes much more important. Energy meter used to measure consumed electricity by building or electrical equipment of various end users. This paper focuses on review of energy meters and power tampering attempts. It will highlight the development of meters from electromechanical meters to smart meters. The need of an era is to develop a more reliable and intelligent smart energy meters. This paper also discussed type of power tampering efforts in energy meters for power theft. The concept of smart meters for removing the power tampering efforts is also discussed.
div data-canvas-width="397.43840959483975">This study presents a new scheme of control for the synchronization of a photovoltaic (PV) system with a three-phase grid without a line sensor. The approach of the proposed synchronization technique is developed to extract the
maximum of PV energy and inject it in the network for various conditions of voltage, and to ensure that the currents injected into the three-phase network emulate the wished sinusoidal forms even when the mains grid voltage is no longer ideal. This paper in troduces a new technique of synchronization and elimination of the disturbances created by the distorted tension based on the direct power control without voltage sensors (VF_DPC) with the help of second-order generalized integrator (SOGI) associated with a self-tuning filter(STF) to extract the fundamental virtual flux. The simulation of the proposed system is realized in MATLAB/Simulink environment.</div
— In a large inter-connected system, large and small generating stations are synchronously connected and hence all stations must have the same frequency. The system frequency deviation is the sensitive indicator of real power imbalance. The main objectives of AGC are to maintain constant frequency and tie-line errors with in prescribed limit. This paper presents two new approaches for Automatic Generation Control using i) combined Fuzzy Logic and Artificial Neural Network Controller (FLANNC) and ii) Hybrid Neuro Fuzzy Controller (HNFC) with gauss membership functions. The simulation model is created for four-area interconnected power system. In this four area system, three areas consist of steam turbines and one area consists of hydro turbine. The components of ACE, frequency deviation (DF) and tie line error (DP tie ) are obtained through simulation model and used to produce the required control action to achieve AGC using i) FLANNC and ii) HNFC with gauss membership functions. The simulation results show that the proposed controllers overcome the drawbacks associated with conventional integral controller, Fuzzy Logic Controller (FLC), Artificial Neural Network controller (ANNC) and HNFC with gbell membership functions . Full Text: PDF
Wind turbines have often connected to small power systems, operating in parallel to diesel generators, as is typically the case in autonomous wind–diesel installations or small island systems with high wind potential. Hence, the modeling and analysis of the dynamic behavior of wind–diesel power systems in presence of wind power will be important. In this paper, the system under study is modeled by a set of dynamic and algebraic equations (DAE). Dynamic behavior of a wind-diesel system is investigated by the proposed dynamic model. Wind-diesel system consists of wind turbines that are connected to synchronous diesel generator via short transmission line with local load. Dynamic stability of autonomous wind–diesel systems are discussed with emphasis on the eigenvalue analysis and the effective parameters on system stability. In this regards, saddle node bifurcation and hopf bifurcation are also investigated. Full Text: PDF
p>This given the outcome of environmental situations in recent years, it has become necessary to use other resolutions for the energy production we need, and among these wind power sources. Since the advent of windmills to the first wind turbines, the technology of aero-motors (or wind sensors) has evolved rapidly. This article presents a study of an axial flow generator, and this mechanism is based on the energy of the wind turbine, this structure solves the problem of the distribution of the magnetic field lines in the armature coils and the inductor of the generator, observing the influence on the voltage from the linear velocity, the density of the injected current and the position along its axis; and that by the method of Finite Elements and is used the computer aided design (CAD), and more particularly the software comsol multiphysics to obtain the results that the good operation of the generator.</p
div data-canvas-width="126.37004132231402">This paper presents an enhanced bacterial foraging optimization (EBFO) algorithm for solving the optimal reactive power problem. Bacterial foraging optimization is based on foraging behaviour of Escherichia coli bacteria which present in the human intestine. Bacteria have inclination to congregate the nutrient-rich areas by an action called as Chemo taxis. The bacterial foraging process consists of four chronological methods i.e. chemo taxis, swarming and reproduction and elimination-dispersal. In this work rotation angle adaptively and incessantly modernized, which augment the diversity of the population and progress the global search capability. The quantum rotation gate is utilized for chemo taxis to modernize the state of chromosome projected EBFO algorithm has been tested in standard IEEE 14,300 bus test system and simulation results show the projected algorithm reduced the real power loss extensively.</div
div data-canvas-width="397.27351844386203">This paper presents a hybrid evolutionary computation algorithm termed as hybrid bacterial foraging-particle swarm optimization (HBFPSO) algorithm, to optimal reactive power dispatch (ORPD) problem. HBFPSO algorithm merges velocity and position updating strategy of particle swarm optimization (PSO) algorithm and reproduction and elimination dispersal of bacterial foraging algorithm (BFA). The ORPD is solved for minimization of two objective functions; system real power loss and voltage stability L-index. The objective is minimized by optimally choosing the control variables; generator excitations, tap positions of on-load tap changing transformers and switched var compensators while satisfying their constraints and also the constraints of dependent variabl
es; voltages of all load buses and reactive power generation of all generators. The proposed approach has been evaluated on a standard IEEE 30 bus test system and 24 bus EHV southern region equivalent Indian power system. The results offered by the proposed algorithm are compared with those offered by other evolutionary computation algorithms reported in the recent state of the art literature and the superiority of the proposed algorithm is demonstrated.</div
p class="Title1">In this article, bacterial foraging optimization (BFO) algorithm is developed for single side optimal bidding strategy in an electricity market. Optimal bidding strategy is one of the important functions in the electricity market along with forecasting of the electricity price and the profit based unit commitment. The prime objective of generating company (Genco) is to maximize their profit when they participate in the bidding process. The BFO algorithm has been used to maximize the probability density function (pdf). In the second stage the BFO algorithm is again applied to maximize the profit of the suppliers. The Proposed algorithm is developed in MATLAB (Version, 2019) and tested on standard test case available in the literature. Also, the simulation results are presented and compared. It is noticed that the proposed method yields the best results in terms of profit.</p
This paper is dedicated to studying the control of the Three Level Boost Converters (TLBC) and the optimization method of Maximum Power Point Tracking (MPPT) based a variable step. The main objective of the optimization is to find a compromise between the response time and the amplitude of the oscillations around the optimal point. The nonlinear behavior of the TLBC is manifested by the presence of the disturbances. For reasons of simplicity of the control, a linearization based on the dynamic compensation of the disturbance is proposed. On the one hand, a cascaded MPPT algorithm and a simple linear regulator allow adjusting the inductance current and a maximum power operation of the wind system. On the other hand, a second linear regulator ensures balancing of the output voltages. The paper proposes a new approach to the optimization of the Inc-Cond MPPT. The suggested contribution consists of using an exponential function of the power derivative to develop a variable step. The adoption of the variable step size according to the dynamics of the wind system implies a compromise between the response time and the amplitude of the ripples around the optimal point. The simulation results showed that a variable step size, especially in transient conditions and during a very rapid climate change recover the optimum power point within a reasonable time and suitable amplitude of the oscillations. The results achieved in this study show the ability of the proposed approach to extract the maximum power according to the available wind speed while guaranteeing a better efficiency. The developed study is summarized by the following points: (a) modeling the wind conversion systems, (b) detailing the control approach of the TLBC and presenting the variable step method (c) presenting the simulations results and evaluating the perf.
This paper is dedicated to studying the control of the three level Boost converters (TLBC) and the optimization method of maximum power point tracking (MPPT) based a variable step. The main objective of the optimization is to find a compromise between the response time and the amplitude of the oscillations around the optimal point. The nonlinear behavior of the (TLBC) is manifested by the presence of the disturbances. For reasons of simplicity of the control, a linearization based on the dynamic compensation of the disturbance is proposed. On the one hand, a cascaded MPPT algorithm and a simple linear regulator allow adjusting the inductance current and a maximum power operation of the wind system. On the other hand, a second linear regulator ensures balancing of the output voltages. The paper proposes a new approach to the optimization of the Inc-Cond MPPT. The suggested contribution consists of using an exponential function of the power derivative to develop a variable step. The adoption of the variable step size according to the dynamics of the wind system implies a compromise between the response time and the amplitude of the ripples around the optimal point. The simulation results showed that a variable step size, especially in transient conditions and during a very rapid climate change recover the optimum power point within a reasonable time and suitable amplitude of the oscillations. The results achieved in this study show the ability of the proposed approach to extract the maximum power according to the available wind speed while guaranteeing a better efficiency. The developed study is summarized by the following points: (a) modeling the wind conversion systems, (b) detailing the control approach of the (TLBC) and presenting the variable step method (c) presenting the simulations results and evaluating the perf