Editor IEEJ - Academia.edu (original) (raw)

Papers by Editor IEEJ

This paper introduces a new feeder branching technique using Genetic Algorithm (GA) to obtain th... more This paper introduces a new feeder branching technique using Genetic Algorithm (GA) to obtain the best location of distribution substation and the optimal feeder routing. This technique aims at achieving minimum cost and voltage drop constraint. To confirm the ability of this technique to find the optimal solution of the general planning problem, the proposed algorithm is applied on two cases: The first case is 25 load points dispersed in a region of 30×20 km2 have to be fed by a 20kv substation and the second case is 104 load points dispersed in a region of 18×15 km2 have to be fed by a 11kv substation. the location and the apparent power of each load point are pre-known.

This paper presents a practical comparison between the Support Vector Machines (SVMs) and the Art... more This paper presents a practical comparison between the Support Vector Machines (SVMs) and the Artificial Neural Networks (ANNs) as identifiers for the Residence Time Distribution (RTD) signal identification. In these identifiers, the cepstral features are extracted from the signal or from its power density spectrum (PDS) estimated using eigenvector method, or from the Discrete Cosine Transform (DCT), then the extracted features feed the identifiers. Both identifiers have been tested using the same RTD signals. The performance of these identifiers is evaluated in the presence of different types of noise. The simulation results proved that, the ANNs based identifier is more reliable in RTD signal identification, but it takes more time with respect to the SVMs based identifier.

Environmental, regulatory and economic constraints have restricted the growth of electric power t... more Environmental, regulatory and economic constraints have restricted the growth of electric power transmission facilities, and the topologies to enlarge the levels of power transmission and enhance stability through existing transmission lines have become greatly needed. Many approaches have been proposed for solving the stability problems found in power system operations. Considering the diversity of both, the solutions and the problems, it is often difficult to identify the most suitable solution. The main purpose of this paper is to demonstrate the capability of Inter Phase Power Flow (IPC) Controller as a means for stability improvement in power systems. In this paper 30 bus system is used as a test bed and the results are shown with and without TC-IPC. The results indicate the power quality improvement of this Flexible AC Transmission System (FACTS) controller in thirty bus system.

This paper presents the solution for controlling the dc-dc switched power of Buck type converter.... more This paper presents the solution for controlling the dc-dc switched power of Buck type converter. This technique states that the control signal can take the values in the range (0, 1) only. Such a control limitation is generally not considered into account when designing the converter regulators. This is only dealt with in the control implementation stage, placing a limiter (controls the range of input signal) between the controller and the controlled system. In this, the control signal limitation is provided by using a non-linear regulator that consists of an internal limiter. The final closed-loop control system is nothing but the non-linear feedback involving a linear dynamics block in closed-loop with a non-linear static element. If these conditions are satisfied when choosing the control design parameters then the regulator improves closed-loop stability and output reference tracking.

This paper presents a novel dc-dc converter with adaptive soft switching as a means to achieve ZV... more This paper presents a novel dc-dc converter with adaptive soft switching as a means to achieve ZVS operation for all the switches. It adopts phase shift modulation features for constant frequency operation and adaptive soft switching at low load. To accomplish this task two loops are employed; inner current control loop is to check the loading condition and turn on of auxiliary switch accordingly. Outer control loop is used to improve the dynamic performance of DC-DC converter by achieving a robust output voltage against load disturbances. This paper also presents the performance of various controllers. A 1kW/100KHz dc/dc converter is simulated and analyzed. Performance of the proposed topology is evaluated at different loads i.e. static and dynamic load (DC motor). An efficiency comparison of the converter with a reported topology has also been carried out.

As view of recent trend in Electricity, Our world is facing the problem in electricity due to lac... more As view of recent trend in Electricity, Our world is facing the problem in electricity due to lacking of fossil fuels. We need to reduce greenhouse gasses emission, have made renewable resources attractive in world energy based economies. The potential for renewable energy resources is enormous. In principle, exponentially exceed the world’s energy demand. Therefore, these types of resources will have a great development in the future global energy portfolio, much of which is now concentrating on advancing their pool of solar energy resources. This paper presents how solar energy is currently used in across the globe.

The production cost of generators could be minimized by optimizing the schedule of generation. Un... more The production cost of generators could be minimized by optimizing the schedule of generation. Unit commitment problem is used for scheduling the generation. In this paper, Hybrid genetic Algorithm and PSO (HGAPSO) is used for solving unit commitment problem. In fitness function, all constraints of unit commitment problem are satisfied without using penalty function. The proposed method is tested on ten generator test system. At the end, the results obtained from HGAPSO are compared with the results of other methods.

Active Power Filters mainly divided based on converters used, i.e. based on converter type, topol... more Active Power Filters mainly divided based on converters used, i.e. based on converter type, topology and the number of phases. Converter types are Current Source Inverter (CSI) with inductive energy storage or Voltage Source Inverter (VSI) with capacitive energy storage. The topology can be shunt, series or combination of both. The third classification is based on the number of phases, such as single phase systems, three phase systems or three phase four wire systems. Criterion for selection of dc link capacitor and interfacing filter design are also discussed.

This paper presents a three-phase, five-level and seven level cascaded multilevel voltage source ... more This paper presents a three-phase, five-level and seven level cascaded multilevel voltage source inverter based active filter to improve the power factor and power quality in the distribution network. Cascaded multilevel configuration of the inverter has the advantage of its simplicity and modularity over the configurations of the diode-clamped and flying capacitor multilevel inverters. Shunt compensation for medium voltage distribution systems requires higher rating for voltage source converters (VSCs). Ratings of the semiconductor devices in a VSC are always limited; therefore, for higher rated converters it is desirable to distribute the stress among the number of devices using multilevel topology. The DSTATCOM helps to eliminate the Total Harmonics Distortion (THD) drawn from a Non-Linear Diode Rectifier Load (NLDRL). The compensation process is based on concept of p-q theory. The simulation of the proposed system is carried out in the MATLAB environment using Simulink and power system toolboxes.

The paper proposes a new concept of protection philosophy for Distribution Grids with high penetr... more The paper proposes a new concept of protection philosophy for Distribution Grids with high penetration of renewable energy. Conventional protection concepts are normally based on protection schemes that consist of definite or inverse time overcurrent relays. In future power systems, these schemes can lead to high fault clearing times, unselective tripping and massive Bus disconnections, which are not acceptable in a deregulated multi owner energy market. This work proposes an efficient intelligent communication based protection algorithm that implements different multi functional protection principles supported by blocking schemes. The real time organization of both the hardware architecture and communication infrastructure of the protection algorithm is illustrated in detail. Special emphasis is given to the network reconfiguration scenario cases and detailed simulation results of such illustrative studied cases are provided. The new protection strategy guarantees protection selectivity and provides Bus unit availability during and after the fault. The intelligent algorithm is applied on existing Distribution network and meaningful conclusions are derived. It is shown that the algorithm enables a uniform fault clearing time (in the order of 78 ms) for all the geographically dispersed circuit breaker positions. The overall combination of this setup is assumed in the MATLAB/Simulink platform and the output parameters are investigated with the existing topology.

To use the induction motor for various applications, controlling of speed is necessary. By having... more To use the induction motor for various applications, controlling of speed is necessary. By having different speed control techniques of induction motor, stator voltage control is the only speed control technique which it can vary the voltage keeping supply frequency as constant at the input side of the motor, it can be provided by AC Chopper. By varying the stator voltage using ON-OFF control PWM technique of AC chopper, the control of speed of an induction motor is achieved. This paper proposes a stator voltage speed control technique of induction motor based AC chopper. This paper also discusses the simulation design, control and analysis of induction motor by using electro dynamics equations with the help of Simulink/MATLAB.

This paper proposes an application of Fast Voltage Stability Index (FVSI) to Reactive Power Plann... more This paper proposes an application of Fast Voltage Stability Index (FVSI) to Reactive Power Planning (RPP) using Cuckoo Search Algorithm (CSA). FVSI is used to identify the weak buses for the Reactive Power Planning problem which involves process of experimental by voltage stability analysis based on the load variation. The point at which Fast Voltage Stability Index close to unity indicates the maximum possible connected load and the bus with minimum connected load is identified as the weakest bus at the point of bifurcation. The proposed approach has been used in the IEEE 30-bus system. Results show considerable reduction in system losses and improvement of voltage stability with the use of Fast Voltage Stability Index for the Reactive Power Planning problem.

Faster development in Dc to Dc converter techniques are undergoing very drastic changes due to th... more Faster development in Dc to Dc converter techniques are undergoing very drastic changes due to that major advancements like low voltage, high power density in electronic industry. Chaos is a kind of quasi-stochastic behaviors of determinate nonlinear system. It is a non-linear phenomenon specifically found in all non-linear systems. The dc-dc converters exhibit a wide range of bifurcation and chaotic behavior under certain operating conditions. This paper analyses the behavior of Luo converter under current control mode. As the reference current is increased, the system becomes unstable to chaos. This is shown by means of bifurcation diagram. This is stabilized by means of time delayed feedback control method. The simulation is done using PSIM.

A new method has been developed for load-flow solution of radial distribution systems using matri... more A new method has been developed for load-flow solution of radial distribution systems using matrix method. The motive of this paper is to propose a technique to identify the nodes beyond each branch with less computational time. The formulated equations have been solved using matrix method. In order to find branch current, node voltage and power loss in the radial distribution network matrix method has been used. Efficacy of this method has been implemented on 33- bus radial distribution systems with constant power (CP), constant current (CC), constant impedance (CZ) composite and exponential load modelling. The suggested method converges well for constant power, constant current, constant impedance, composite and exponential load modeling. The advantages of proposed method have compared with several existing methods in terms of relative value CPU time and memory size. The proposed method requires much less time to converge and also require less memory size when compared with the several existing methods.

AC asynchronous electrical motors especially squirrel cage induction motor presents the greater a... more AC asynchronous electrical motors especially squirrel cage induction motor presents the greater advantages on cost and energy efficiency as compared with other industrial solutions for varying speed applications. The force-commutated power electronics switches (GTOs, MOSFETs, and IGBTs etc) based inverters are widely employed these days in the conversion of constant speed into variable speed induction motors. Due to the invention of these advanced power electronics switches (GTOs, MOSFETs, IGBTs etc) with improved characteristics, the PWM inverter fed induction motors are widely replacing DC motors and thyrister bridges day by day in the industries. The torque control or field control method may be used with PWM inverter fed induction motors jointly and can achieve the same flexibility in speed and torque control as with DC motors. In this present paper, an IGBT inverter fed squirrel cage induction motor with torque control technique is developed and simulated in the recent MATLAB/Simulink environment and observed the transient characteristics of the used motor. Many motor parameters have been used for induction motor analysis purpose. Further, V/f control and Total Harmonics Distortion (THD) analysis has also been carried out. Though, the stator current parameter of the motor has been widely used from last three decades with Motor Current Signature Analysis (MCSA) technique. Therefore, in the THD analysis, only stator current motor parameter has been analysed.

In recent years, the power industry has experienced significant changes on the power distribution... more In recent years, the power industry has experienced significant changes on the power distribution systems primarily due to the implementation of smart-grid technology and the incremental implementation of distributed generation. The distribution power system is generally designed for radial power flow, but with the introduction of DG, power flow becomes bidirectional. Whether the impact of the DG is positive or negative on the system will depend on the location and size of the DG. This paper focuses on testing various indices and using effective techniques for the optimal placement and sizing of the DG unit by minimizing power losses and voltage deviation. A 33-bus radial distribution system has been taken as the test system. The feasibility of the work lies on the fast execution of the programs as it would be equipped with the real time operation of the distribution system and it is seen that execution of the DG placement is quite fast and feasible with the optimization techniques used in this work.

Power quality is the most important aspect in the present power system environment. Among all the... more Power quality is the most important aspect in the present power system environment. Among all the power quality problems most frequently occurring disturbances, affecting the quality of power are voltage sags and swells. Custom power device, Dynamic Voltage Restorer (DVR) connected in series with a goal to protect the loads from source side voltage disturbances. In this paper single phase DVR is adopted for each phase instead of using three phase DVR to compensate unbalanced sags/swells. Programmable voltage source is used to create sags/swells with required magnitude and time period. In this paper voltage type Impedance Source Inverter (ISI) is employed to compensate deep voltage sags/swells. DVR’s employed as series compensators in IPFC scheme to compensate voltage disturbances in individual feeders. Comparative study between PI and Fuzzy controllers is done. The project is carried out in Matlab/Simulink software.

In this paper a new connection for a unified power quality conditioner (UPQC) has been proposed t... more In this paper a new connection for a unified power quality conditioner (UPQC) has been proposed to improve the power quality of two feeders in a distribution system. A UPQC consists of a series voltage-source converter (VSC) and a shunt VSC both joined together by a common dc bus. It is demonstrated how this device is connected between two independent feeders to regulate the bus voltage of one of the feeders while regulating the voltage across a sensitive load in the other feeder. Since the UPQC is connected between two different feeders (lines), this connection of the UPQC will be called an interline UPQC (IUPQC). The structure, control and capability of the IUPQC are discussed in this paper. The efficiency of the proposed configuration has been verified through simulation studies using MATLAB/SIMULINK.

This paper presents an application of Fast Voltage Stability Index (FVSI) to Imperialistic Compet... more This paper presents an application of Fast Voltage Stability Index (FVSI) to Imperialistic Competitive Algorithm (ICA) for solving reactive power dispatch problem in a power system. Generator terminal voltages, reactive power generation of the capacitor banks and tap changing transformer setting are taken as the optimization variables. Imperialistic Competitive Algorithm (ICA), is presented in this paper for solving global unconstrained optimization problem. In order to evaluate the proposed algorithm, it has been tested on IEEE 30 bus system and the performance of the algorithm is compared with gravitational search algorithm (GSA). Results show that (ICA) is more efficient than others for solution of single-objective Optimal VAr problem.

Grid connected solar system uses to have converter circuits followed by two levels: A DC/DC boost... more Grid connected solar system uses to have converter circuits followed by two levels: A DC/DC boosters and PWM Inverter. This combination of converters leads to decrement of Quality and efficiency of electric power. This paper proposes a single phase thirteen-level photo voltaic inverter for grid connected solar system with a novel pulse width modulated control scheme. The fast variations of solar radiation can be compensated by digital proportional-integral controller. The inverter offers less total harmonic distortion and good power factor. This inverter topology uses two reference signals instead of one reference signal to generate PWM signals for the switches. Both the reference signals Vref1 and Vref2 are identical to each other, except for an offset value equivalent to the amplitude of the carrier signal Vc. Because the inverter is used in a Photo Voltaic system, a proportional–integral current control scheme is employed to keep the output current sinusoidal and to have high dynamic performance under rapidly changing atmospheric conditions and to maintain the power factor at near unity. PV arrays are connected to the inverter via a dc–dc boost converter. The proposed system offers improved performance over five level inverters.

comparison with the classical Russian PID power system stabilizer . Our present study was perform... more comparison with the classical Russian PID power system stabilizer . Our present study was performed using a GUI realized under MATLAB in our work.

 Abstract-Pollution due to greenhouse gas emissions in urban areas and excessive dependence foss... more  Abstract-Pollution due to greenhouse gas emissions in urban areas and excessive dependence fossil fuel has been a huge threat in the sustainable development of the transportation sector. So, there is a need for a solution that can tackle this situation. Electric vehicles can be one of the most promising remedies to tackle this problem. They provide energy conservation and environmental protection. Electric vehicles are propelled by an electric motor powered by rechargeable battery packs. They have both positive and negative impact on the power grid. For instance, in order to evaluate the impact on electric vehicles on demand profile, one needs to know about 1)charging process of electric vehicles, 2) amount of electrical energy required, 3) amount of power required, 4)state of charge of the battery. This paper extracts the comparison between the load profile of the distribution system without EV's and with EV's connected. Also it shows the voltage unbalance caused by EV's interconnection with the grid.

Voltage profile improvement of rural feeder in uttarakhand state of India using conductors type a... more Voltage profile improvement of rural feeder in uttarakhand state of India using conductors type and quality based technique is discussed. The energy losses are remarkably reduced and voltage profile is improved using Backward and Forward Sweep Method in MATLAB Software. The possible combinations of conductor are proposed after technical analysis.

At present, multilevel inverters are extensively used in industries for high power and high volta... more At present, multilevel inverters are extensively used in industries for high power and high voltage applications. Two categories into which inverters can be broadly classified are two level inverters and multilevel inverters. The multilevel began with the three level converters. One advantage that multilevel inverters have compared to two level inverters is minimum harmonic distortion. This paper deals with study and analysis of three level diode clamped MOSFET based inverters and its applications in industries. The main purpose of the paper is to study and implement 3 level diode clamped inverter using MOSFET's, the PWM signals used to switch these MOSFET's has been generated using PWM IC HEF4752VP. However, the output voltage is smoother with a three level converter, these results in smaller harmonics, but on the other hand it has more components and it is little complex to control in hardware. 

 Abstract-Besides the advantages, there are some limitations of FLCs. The tuning of an FLC is a ... more  Abstract-Besides the advantages, there are some limitations of FLCs. The tuning of an FLC is a very difficult task. To make the tuning easy and efficient, there are several structures of fuzzy logic controllers are available. This paper considers new structures of fuzzy logic controllers. Two structures, self-tuning FLC (STFLC) and fuzzy supervised conventional PI controller (GSPI) are considered. In FLC control rules and scaling factors play very important role. In this paper, a self-tuning PI-like FLC (STFLC) is used for the tuning of output scaling factor. In FSPI, we tune the PI controller parameters with FLC. So, it adds the advantages of PID controller and FLC. The design of these controllers is discussed. These are implemented to control three non-linear example systems. The performance of FLC, STFLC and FSPI controller is compared with each other. It is found that STFLC and FSPI controller give better performance than the conventional PI controller or simple FLC.

Load frequency control is a significant control process that operates constantly to balance the g... more Load frequency control is a significant control process that operates constantly to balance the generation and load in power systems at a minimum cost. The LFC system is responsible for frequency control, power interchange and economic dispatch. This thesis reviews the main structures, configurations, modelling and characteristics of Load Frequency Control systems in a deregulated environment and addresses the control area concept in restructured Power Systems. The application of artificial neural network based FIS approach to load frequency control (LFC) of a three unequal area hydrothermal system. Appropriate generation rate constraints (GRC) have been considered for the thermal and hydro plants. The design objective is to improve the frequency and tie line deviations of the interconnected system. The performance of FIS controller is compared with the results of integral squared error (ISE) criterion based integral controller. Simulation results are presented to show the improved performance of FIS controller in comparison with the conventional integral controller. The results indicate that the controllers exhibit better performance. In fact, FIS approach satisfies the load frequency control requirements with a reasonable dynamic response.

This paper presents a high step-down transformerless single-stage single-switch ac/dc converter s... more This paper presents a high step-down transformerless single-stage single-switch ac/dc converter suitable for universal line applications (90-270 V rms ). The topology integrates a buck-type power-factor correction (PFC) cell with a buck-boost dc/dc cell and part of the input power is coupled to the output directly after the first power processing. With this direct power transfer feature and sharing capacitor voltages, the converter is able to achieve efficient power conversion, high power factor, low voltage stress on intermediate bus (less than 130 V) and low output voltage without a high step-down transformer. The absence of transformer reduces the component counts and cost of the converter. Unlike most of the boost-type PFC cell, the main switch of the proposed converter only handles the peak inductor current of dc/dc cell rather than the superposition of both inductor currents. Detailed analysis and design procedures of the proposed circuit are given and verified by experimental results. Index Terms-Direct power transfer (DPT), integrated buck-buck-boost converter (IBuBuBo), power-factor correction (PFC), single-stage (SS), transformerless.

1432 Chaitanya et. al., Comparison of Fuzzy Logic, PI and Energy based PI DC-Link Voltage Control... more 1432 Chaitanya et. al., Comparison of Fuzzy Logic, PI and Energy based PI DC-Link Voltage Controller for compensating AC and DC Loads using Three Phase D-STATCOM  Abstract: While compensating rapidly varying unbalanced and nonlinear loads the transient response of

 Abstract-Technology has evolved constantly over the years where the demand of Microstrip Patch ... more  Abstract-Technology has evolved constantly over the years where the demand of Microstrip Patch antenna has been growing tremendously due to low volume and profile configuration, light weight and low fabrication characteristics. But researchers are facing difficulty to improve both bandwidth and gain for Microstrip Patch antenna at same time under Ku band frequency range. In this paper a compact modified structure of E-shaped Microstrip patch antenna has been designed with artificially man made Double Negative (DNG) Metamaterials. These advance material depicts unusual electromagnetic properties which are not available in nature, such as negative permittivity (ε r ) and permeability (µ r ). Due to its amazing feature, it has the capacity to enhance antenna characteristic rapidly. The intended design and feeding technique provides the proposed antenna to operate at Ku band range with approximately total 4.40 GHz bandwidth which covers 73.33% of this band. The proposed antenna resonates at 14.97 GHz with total field directivity 9.4 dBi respectively. The design has been made on low cost material of FR4 substrate with dielectric constant of 4.2. This paper also presents four particular Microstrip patch antenna design including proposed antenna with a brief comparative study between them where effect of different antenna parameters are studied.

 Abstract-Operation of modern power systems envisages the participation in optimization process ... more  Abstract-Operation of modern power systems envisages the participation in optimization process of some thermal power stations with limited stock of a fuel resources which can be used during the planning period for electric power production. In such conditions the problem of optimal planning of power systems short term modes can be solved by applying the algorithms specially developed for those purposes. In the present research study the mathematical description and decision algorithms of optimal planning of power systems short term modes in the circumstance of the presence of the thermal power stations with limited stocks of fuel are shown. The results of experimental research of efficiency of the proposed algorithms while its applying to the example of optimal covering of power systems load schedule by thermal power stations, some of which has limited stock of fuel for considered period, are presented.

 Abstract-A singularly perturbed discrete power system with two-time-scales is considered. An op... more  Abstract-A singularly perturbed discrete power system with two-time-scales is considered. An optimal controller using Pontriagin's minimum principle (PMP) is designed for this stiff system. However the solution for control law of this type of system requires special numerical techniques. Hence it is required to go for a suboptimal controller that alleviates this problem. Singular perturbation method (SPM) that reduces the order and removes the stiffness of the system is an ideal choice for this problem. The SPM consists of outer, one initial boundary layer correction (BLC) and one final BLC solutions for this problem. The method is applied to a single area power system problem. The results substantiate the proposed suboptimal controller.

The liquid level accurate control of a four water tank system has become a research focus due to ... more The liquid level accurate control of a four water tank system has become a research focus due to the nonlinear process and multiple variables. this paper deals with the use of computer simulation and simulate environments in a software which illustrates real-world applications of fundamental control principles. The goals of this paper can be summarized as follows: 1) Introduction and the practice of control engineering principles. 2) Show using a simple and challenging example -the four tank process-as many features of multivariable control as possible. 3) Encourage the students promoting an active attitude using problem-based learning via open-ended control problems. 4) Investigation of PID controller on a four Tank process and changing value of P, I, D and effect of these changes.

For proper functioning and operation of various devices used in industrial applications, there is... more For proper functioning and operation of various devices used in industrial applications, there is a need for undergoing rectification. They are connected to the grid comprising of non-linear loads and thus have non-linear input characteristics, which results in production of non-sinusoidal line current. Also, current comprising of frequency components at multiples of line frequency is observed which lead to line harmonics. Due to the increasing demand of these devices, the line current harmonics pose a major problem by degrading the power factor of the system thus affecting the performance of the devices. Hence there is a need to reduce the line current harmonics so as to improve the power factor of the system. This has led to designing of Power Factor Correction circuits.

With the increasing penetration of wind power into electric power grids, energy storage devices w... more With the increasing penetration of wind power into electric power grids, energy storage devices will be required to dynamically match the intermittency of wind energy. This paper proposes a novel two-layer constant power control scheme for a wind farm equipped with doubly fed induction generator (DFIG) wind turbines. Each DFIG wind turbine is equipped with a super capacitor energy storage system (ESS) and is controlled by the low-layer wind turbine generator (WTG) controllers and coordinated by a high-layer wind farm supervisory controller (WFSC). The WFSC generates the active power references for the low-layer WTG controllers according to the active power demand from or generation commitment to the grid operator; the low-layer WTG controllers then regulate each DFIG wind turbine to generate the desired amount of active power, where the deviations between the available wind energy input and desired active power output are compensated by the ESS. Simulation studies are carried out in PSCAD/EMTDC on a wind farm equipped with 15 DFIG wind turbines to verify the effectiveness of the proposed control scheme.

In the area of power quality conditioners, series hybrid power filter has been focused more becau... more In the area of power quality conditioners, series hybrid power filter has been focused more because of its multi-functionality. The hybrid filter is implemented with three phase cascaded seven level inverter and operates with resonant passive LC filter connected in parallel with power lines. Control strategies are based on extracting either source current harmonics or load voltage harmonics. While passive filters mitigate load produced harmonics, the active filter helps to enhance filtering properties of passive filter. The control strategy is based on P-Q theory. The potential transformers are connected in series with the line which has low magnetic saturation characteristics. Series active filters are used to compensate the voltage producing harmonic sources as well as current producing harmonic source type loads. Thus it acts as harmonic isolator improves the filtering characteristics of passive filter. For current harmonics the system produces voltage proportional to the current and offers high impedance path to the current harmonics. It produces voltage of same amplitude but opposite to load harmonic voltage to nullify the harmonics injected into the system. The validity of the control scheme is verified by simulation study with help of MATLAB/SIMULINK and comparative analysis is carried out with help of simulated values to obtain the harmonic values within standard values.

A new series power conditioning system using a matrix converter is proposed. The proposed solutio... more A new series power conditioning system using a matrix converter is proposed. The proposed solution has utilized a single AC/AC power converter for interface as an conventional AC/DC/AC converter. The dynamic model is used to design a vector control system that seamlessly integrates functional of compensating load voltage and managing energy storage during voltage sag and idling modes. The purpose of matrix converter used in dynamic voltage restorer (DVR) for power quality enhancement, which is connected in between the feeder to secure the electric power from sags. The DVR is based on dqo algorithm which is discussed with matrix converter to inject external supply into the feeder by means of a series transformer. Harmonics are produced due to non-linear loads, and it is filtered out by a filter which is connected at terminal end of the system. The simulation results are carried out by MATLAB and the performance of proposed method is verified.

Multilevel inverter technology has emerged recently as a very important alternative in the area o... more Multilevel inverter technology has emerged recently as a very important alternative in the area of high-power mediumvoltage energy control. This paper presents the most important topologies like diode-clamped inverter (neutral-point clamped), capacitor-clamped (flying capacitor), and cascaded multicell with separate dc sources. Emerging topologies like asymmetric hybrid cells and soft-switched multilevel inverters are also discussed. This paper also presents the most relevant control and modulation methods developed for this family of converters: multilevel sinusoidal pulsewidth modulation, multilevel selective harmonic elimination, and space-vector modulation. Special attention is dedicated to the latest and more relevant applications of these converters such as laminators, conveyor belts, and unified powerflow controllers. The need of an active front end at the input side for those inverters supplying regenerative loads is also discussed, and the circuit topology options are also presented. Finally, the peripherally developing areas such as high-voltage high-power devices and optical sensors and other opportunities for future development are addressed.

The electricity requirements of the world including India are increasing at alarming rate and the... more The electricity requirements of the world including India are increasing at alarming rate and the power demand has been running ahead of supply renewable. The recent severe energy crisis has forced the world to develop new and alternative methods of power generation. Solar power resources have been increased since last decade. The future visions of Power System contain penetration of inverter which is used to convert power from DC (direct current) to AC (alternating current). The behavior of this device is dependent upon the control algorithm. In particularly the Voltage Drive Mode is used to improve the power quality of the three phase inverter. Sinusoidal current generation provides better effects on power quality. The Voltage Drive Mode aims for perfectly balanced sinusoidal voltage on all the three phases. The three phase inverter can be split into two circuits: power circuit and control circuit. The power circuit consists of fully controlled inverter circuit, which can convert input DC voltage into AC voltage with the help of firing pulses which are being produced by the control circuit. In this project, the Space Vector Pulse Width Modulation (SVPWM) technique is used to control the switching time of PWM. The harmonic distortion can be reduced by using this technique.

This project presents super conducting magnetic energy storage (SMES) control system for the powe... more This project presents super conducting magnetic energy storage (SMES) control system for the power distribution grid which integrates renewable generation and electric vehicles (EVs) together. With the use of SMES, any transient unbalance caused by wind power variation can be recovered so that the system frequency can be stabilized. Also, with the use of EVs, the steady-state load demand can be redistributed to facilitate the adoption of wind power generation. Finally, simulation results verify that the use of both SMES and EVs can effectively perform power balancing under both the transient and steady states. The proposed method was developed by using MATLAB/SIMULINK.

In the grid connected network, it is especially difficult to support the critical load without un... more In the grid connected network, it is especially difficult to support the critical load without uninterrupted power supply. The proposed Wind-Hydro hybrid system with battery energy storage is used to maintain the voltage profile and support the real and reactive power in the grid. The proposed system employing one squirrel cage induction generator driven by variable speed wind turbine. And another squirrel cage induction generator driven by constant power hydro turbine feeding to the grid. The scheme can also be operated as stand-alone system in case of grid failure. The system is simulated in MATLAB/SIMULINK and results are presented for various types of linear, nonlinear, and dynamic loads and under varying wind speed conditions.

This paper investigates the performances of a dqo based synchronous controlled inverter which is ... more This paper investigates the performances of a dqo based synchronous controlled inverter which is connected with any distributed generators (i.e. dc source-solar .fuel cell, etc).This dqo based synchronous controller effectively maintains the magnitude of load voltage & frequency within the allowable range. The control technique can generate the needed phase angle for utility synchronization by using this abc to dqo transformations. This paper also deals with islanding operation which activates when the voltage and frequency of the grid exceeds the specified value at the point of common coupling. The effectiveness of control technique is demonstrated using MATLAB simulation.

In a power system, transformers and other electrical equipment have to protect not only from shor... more In a power system, transformers and other electrical equipment have to protect not only from short circuit, but also from unusual operating conditions, such as over loading, and dissimilar fault protection. The increased growth in power systems both in size and difficulty has brought the need for fast and reliable protection scheme for main equipment's like transformer. The power transformer protective relay should block the tripping during magnetizing inrush and rapidly initiate the tripping during internal and external faults. The concept of magnetizing inrush current and over-excitation phenomena as they belong to causes of the protection of maloperation. This project work proposes for Identification of Inrush Current & Fault Current of power transformer for proper protection scheme. In the proposed algorithm, Feed Forward Back Propagation Network (FFBPN) are used as a classifier and address the challenging task of detecting magnetizing inrush from fault current. The algorithm is evaluated using MATLAB simulation. The results verify that the proposed technique is faster, stable and more reliable recognition of transformer inrush and fault condition.

This paper analyses the operation of an adaptive neurofuzzy inference system (ANFIS)-based maximu... more This paper analyses the operation of an adaptive neurofuzzy inference system (ANFIS)-based maximum power point tracking (MPPT) for solar photovoltaic (SPV) energy generation system. The MPPT works on the principle of adjusting the voltage of the SPV modules by changing the duty ratio of the Quasi-zsource inverter. The duty ratio of the inverter is calculated for a given solar irradiance and temperature condition by a closed-loop control scheme. The closed-loop control of the qZSI regulates the duty ratio and the modulation index to effectively control the injected power and maintain the stringent voltage, current, and frequency conditions. The ANFIS is trained to generate maximum power corresponding to the given solar irradiance level and temperature. The response of the ANFIS-based control system is highly precise and offers an extremely fast response. The main objective for a grid-connected Photovoltaic (PV) inverter is to feed the harvested energy from PV panels to the grid with high efficiency and power quality. The simulation results show that the proposed ANFIS MPPT controller is very efficient, very simple and low cost.

The electricity market scenario is changing day by day and consumers are demanding an uninterrupt... more The electricity market scenario is changing day by day and consumers are demanding an uninterruptible, high quality of power. Because of the new regulation policy, the consumers are seldom free to select their choice of power providers who can supply good quality power. Case studies on quality measurements in various LT and HT industries carried by Kongu Engineering College observes that, the industries face so many problems like reactor failure, heating in the neutral wire of four wire system etc., because of low power quality. With the increased usage of power electronic based components, the power quality is derating. The major cause for the power quality deterioration in power system is due to the penetration of non-linear loads and power electronics based switching devices. Instead of using switching devices in general, if multilevel inverters are used, the harmonic distortion is reduced to a greater extent. In general, there are several switching techniques that have been used to reduce the harmonic content. SHEPWM is one such technique at fundamental frequency to reduce the lower order harmonics. The forging behavior of swarms of honey bees is utilized here for the optimization of the switching angles, in order to reduce the harmonic content and achieve the good power quality. The main objective is to eliminate the lower order harmonics using SHEPWM strategy and to optimize the switching angle by using Bee algorithm.

As the wind power installations are increasing in number, Wind Turbine Generators (WTG) are requi... more As the wind power installations are increasing in number, Wind Turbine Generators (WTG) are required to have Fault Ride-Through (FRT) capabilities. Lately developed grid operating codes demand the WTGs to stay connected during fault conditions, supporting the grid to recover faster back to its normal state. In this paper, the generator side converter incorporates the maximum power point tracking algorithm to extract maximum energy from wind turbine system. A hybrid control scheme for energy storage systems (ESS) and braking choppers for fault ride-through capability and a suppression of the output power fluctuation is proposed for permanent-magnet synchronous generator (PMSG) wind turbine systems. During grid faults, the dc-link voltage is controlled by the ESS instead of the line-side converter (LSC), whereas the LSC is exploited as a STATCOM to inject reactive current into the grid for assisting in the grid voltage recovery. A simple model of the proposed system is developed and simulated in MATLAB environment. The effectiveness of the system is validated through extensive simulation results Index Terms-Boost converter, Braking Chopper(BC),dc-link control, energy storage system(ESS),ride through, STATCOM, Permanent Magnet Synchronous Generator.

 Abstract-The high-voltage step-up dc-dc converters are required as an interface between the ava... more  Abstract-The high-voltage step-up dc-dc converters are required as an interface between the available low voltage sources and the output loads, which are operated at much higher voltages. Examples of such applications re as follows. Different distributed energy storage components such as batteries, fuel cells, and ultra capacitors are used in the power trains of hybrid electric vehicles (HEV), electric vehicles (EV), and fuel cell vehicles (FCV). Telecom and the computer industry utilize the standard batteries, with low voltage levels, as back-up power source .The automotive headlamps, using the high-intensity discharge lamp ballasts.

 Abstract-Wireless communication has been evolving since the birth of radio wave. Recently impor... more  Abstract-Wireless communication has been evolving since the birth of radio wave. Recently importance and necessity of satellite and radar communication became common practice around the world where demand for multiband operating and miniature dimension antennas and devices are growing faster. Microstrip patch antenna are widely used to fulfill desirable requirements due to there low profile, inexpensive and robust feature. This paper represents a design of compact slotted Microstrip patch antenna with substrate layer on the top. The design has been configured on the top FR4 substrate having dielectric constant of 4.2 with thickness of 1.6mm. The proposed scheme and probe feeding technique provides designed antenna to operate in multiband frequencies under X and Ku band spectrum. The antenna resonates at 7.4 GHz having 308 MHz bandwidth as well as 9.68 GHz, 12.04 GHz and 12.86 GHz under single bandwidth of 4.8 GHz. The antenna has return loss of -21.45 dB, -33.51 dB, -16.48 dB and -10.78 dB at operating frequencies respectively with reasonable directivity and efficiency. The design concepts of the proposed antenna are presented and simulation results are discussed.

The phase-shifted full bridge (PSFB) Soft switched -PWM converter is widely used in medium to hig... more The phase-shifted full bridge (PSFB) Soft switched -PWM converter is widely used in medium to high power applications. These converters have many limitations like reduced range of soft switching, conduction losses etc. To overcome these limitations an additional auxiliary circuit is used. The placement of this auxiliary circuit results in variation in the converter's performance. In this paper a detailed review for these topologies is presented. The merits and limitations of these topologies have been analyzed and their key features and characteristics have been compared.

 Abstract-Wind power is the rapidly growing renewable source for the past twenty years. As Wind ... more  Abstract-Wind power is the rapidly growing renewable source for the past twenty years. As Wind behavior is chaotic in nature, its predictability is difficult. At the same time accurate forecasting methods are very much essential, when wind farms are integrated into the power grid. Further, wind power forecasting answers the issues related to reserve allocation. In this paper 30 hour ahead wind speed has been forecasted using Back Propagation Algorithm (BPA) based artificial neural network (ANN)and BPA based Adaptive Wavelet Neural Network (AWNN). For wind speed forecasting the time series data of wind speed is collected from the National Renewable Energy Laboratory (NREL) website. In this work, hourly averaged 10-min wind speed data sets for the year 2004 at site 7263 in the Midwest ISO region is taken for analysis. Data sets are normalized to [-1, 1] to improve the training performance of forecasting models. Total 8760 samples were taken for this forecasting analysis (Hourly data for total 365 days that is 365*24 = 8760). After forecasting analysis Mean Absolute Percentage Error (MAPE) is calculated using both BPA and AWNN. The forecasting error with AWNN is found to be minimum.

 Abstract-This work introduces a new combination of holders with application on digital control ... more  Abstract-This work introduces a new combination of holders with application on digital control systems .This holder is a combination of zero-order hold (ZOH) and first-order hold (FOH) that has the capability of both holders. It is obvious that, At low frequencies, FOH is a better approximation to an ideal low-pass filter than ZOH, but at high frequencies, ZOH is better than FOH. Because of this fact, we introduced a combination of ZOH and FOH, we used of a frequency switch, that it has been set with input frequency, that it switches by input frequency between ZOH and FOH, therefore it has the same behavior as FOH at low frequencies and the same behavior as ZOH at high frequencies, and hence we suggested a combination of ZOH and FOH that it works more accurate at two conditions, low and high frequencies. Also simulation results are studied to show the effectiveness of the proposed holder and better performance results in comparison with ZOH and FOH.

This paper is based on the performance of the Switched Reluctance Motor (SRM) drives using Z-Sour... more This paper is based on the performance of the Switched Reluctance Motor (SRM) drives using Z-Source Inverter with the simplified rule base of Fuzzy Logic Controller (FLC) with the output scaling factor (SF) self-tuning mechanism are proposed. The aim of this paper is to simplify the program complexity of the controller by reducing the number of fuzzy sets of the membership functions (MFs) without losing the system performance and stability via the adjustable controller gain. ZSI exhibits both voltage-buck and voltage-boost capability. It reduces line harmonics, improves reliability, and extends output voltage range. The output SF of the controller can be tuned continuously by a gain updating factor, whose value is derived from fuzzy logic, with the plant error and error change ratio as input variables. Then the results, carried out on a four-phase 6/8 pole SRM based on the dSPACEDS1104 platform, to show the feasibility and effectiveness of the devised methods.

Voltage disturbance is the most important power quality problem faced by many industrial equipmen... more Voltage disturbance is the most important power quality problem faced by many industrial equipment. This paper deals with the application of a static transfer switch (STS) for protection in the distribution system that has been evaluated through modeling and simulation. The operation principles of STS have been explained in detail and then it has been modeled with PSCAD/EMTDC program. In the STS model, a new control scheme has used and simulation results obtained also prove that the STS can mitigate voltage sag and protect bus bar voltage from various types of faults.

One of the prerequisite to have an accurate measurement of radiation field is the use of reliable... more One of the prerequisite to have an accurate measurement of radiation field is the use of reliable measuring instruments and the measurement values should have their defined uncertainties, which are inherent in a measurement process. In this paper, the sources of uncertainty inherent to calibration of dose rate meters in calibration laboratory at Egyptian atomic energy authority (ECLEG) are investigated, identified, analyzed and evaluated. Some of these sources are evaluated from the statistical distribution of the results and can be characterized by standard deviation. The other uncertainty sources are evaluated based on experience or other information. The combined and expanded uncertainties are calculated in order to have an accurate measurement of dose rate meters and to meet the requirements of ISO 17025. Results show a typical uncertainty in the calibration of approximately 4.2%.

the energy demand all over the world is increasing rapidly with the passage of time. In Pakistan,... more the energy demand all over the world is increasing rapidly with the passage of time. In Pakistan, the demand and supply equation is almost reversed. The short fall has reached up to 5000 MW. The Pakistan Electric Power Company (PEPCO) is currently facing the generation shortfall. The transmission lines are already working on full load/ over load condition. National Transmission & Dispatch Co. (NTDC) is supplying power to PEPCO and working as sole Transmission System Operator (TSO) in the country. In this worst scenario, the NTDC has to supply the electric power to Karachi Electric Supply Company (KESC) to meet their demands.

This paper presents an algorithm for solving the multi-objective reactive power dispatch problem ... more This paper presents an algorithm for solving the multi-objective reactive power dispatch problem in a power system. Modal analysis of the system is used for static voltage stability assessment. Loss minimization and maximization of voltage stability margin are taken as the objectives. Generator terminal voltages, reactive power generation of the capacitor banks and tap changing transformer setting are taken as the optimization variables. This paper introduces a new search-acceleration parameter into the formulation of the original shuffled frog leaping (SFL) algorithm to create a modified form of the shuffled frog algorithm (MSFL) for solving above problem. . The shuffled frog-leaping algorithm draws its formulation from two other search techniques: the local search of the 'particle swarm optimization' technique; and the competitiveness mixing of information of the 'shuffled complex evolution' technique.

Some countries did not have adequate fuel and water power resources, which led them to look for a... more Some countries did not have adequate fuel and water power resources, which led them to look for alternative ways of generating electricity such as wind power, solar power, geothermal power and biomass power, called renewable energy. Wind energy is one of the most available and exploitable forms of renewable energy due to their advantages. However the high penetration of wind power systems in the electrical network has introduced new issues in the stability and transient operation of power system. The majority of wind farms installed are using fixed speed wind turbines equipped with squirrel cage induction generator (SCIG). Therefore, the analysis of power system dynamics with the SCIG wind turbines has become a very important research issue, especially during transient faults. This paper provides an assessment of wind penetration effects on the power system transient stability. The wind generators considered are the squirrel cage induction generator (SCIG), which is a fixed speed.

Order PID controller as a supplementary controller to improve the dynamics of LFC in a Multi area... more Order PID controller as a supplementary controller to improve the dynamics of LFC in a Multi area deregulated power system. FOPID is a PID controller whose derivative and integral orders are of fractional rather than integer. The extension of derivative and integral order from integer to fractional order provides more flexibility in design of the controller, thereby controlling wide range of dynamics of a system. Using Integral Time multiplied Absolute Error (ITAE) as the performance criteria to be optimize the FOPID controller parameters: Proportional (K p ), Integral (K i ), Derivative (K d ) gains, integral order (λ), and the derivative order (μ) operators are optimized using Evolutionary Real coded Genetic algorithm and Firefly algorithm a hybrid algorithm (GA-FA). The feasibility and robustness of the proposed controller is investigated on a three-area interconnected power system consisting of Thermal-Thermal unit in area-I, Hydro-Thermal unit in area-II and Thermal-Gas unit in area-III. The dynamics of frequency, GENCOs power generation and tie-line power deviations were investigated by considering the possible contracts between various GENCOs and DISCOs of deregulated power system using DISCO participation matrix (DPM). The simulation results show the proposed FOPID controller tuned by the proposed Hybrid Genetic-Firefly algorithm (GA-FA) exhibits improved dynamic performance over conventional PID controller.

A Power quality problem is an occurrence manifested as a nonstandard voltage, current or frequenc... more A Power quality problem is an occurrence manifested as a nonstandard voltage, current or frequency that results in a failure or mis-operation of end use Equipments. Utility distribution networks, sensitive industrial loads, and critical commercial operations all suffer from various types of outages and service interruptions which can cost significant financial 1oss per incident based on process down-time, lost production, idle work forces, and other factors. With the restructuring of Power Systems and with shifting trend towards distributed and dispersed Generation, the issue of Power Quality is going to take newer dimensions. The aim therefore, in this work, is to identify the prominent concerns in the area and thereby to recommend measures that can enhance the quality of the power, keeping in mind their economic viability and technical repercussions. In this paper three custom power controllers: DVR, DSTATCOM (modelled in MATLAB/Simulink), PWM Switched Autotransformer (modelled in PSCAD/EMTDC & MATLAB/SIMULINK) are presented. Comprehensive results are presented to assess the performance of each device to mitigate the Voltage sag and economical device is proposed.

Receiver aperture diameter, Dr 0.1≤ Dr, m ≤ 0.6 Maximum bit rate without any limitations, Bu (Sho... more Receiver aperture diameter, Dr 0.1≤ Dr, m ≤ 0.6 Maximum bit rate without any limitations, Bu (Short range) 0.1 Mbit/sec Maximum bit rate without any limitations, Bu (very short range) 2 Mbit/sec Bit rate , BR (for short range) BR=0.01 Mbit/sec Bit rate , BR (for very short range) BR=1 Mbit/sec Transmission distance, Lm (Short range) 100 m ≤ Lm, m ≤ 1000 Transmission distance, Lm (very short range) 10 m ≤ Lm, m ≤ 100 Receiver angle, φ φ =60 degree Pure sea water Cc=0.03 mg/m 3 , wc=0.035 mg/m 3 Dr. Ahmed Nabih Zaki Rashed was born in Menouf city, Menoufia State, Egypt country in 23 July, 1976. Received the B.Sc., M.Sc., and Ph.D. scientific degrees in the Electronics and Electrical Communications Engineering Department from Faculty of Electronic Engineering, Menoufia University in 1999, 2005, and 2010 respectively. Currently, his job carrier is a scientific lecturer in Electronics and Electrical Communications Engineering Department, Faculty of Electronic Engineering, Menoufia university, Menouf, postal Menouf city code: 32951, EGYPT. His scientific master science thesis has focused on polymer fibers in optical access communication systems. Moreover his scientific Ph. D. thesis has focused on recent applications in linear or nonlinear passive or active in optical networks. His interesting research mainly focuses on transmission capacity, a data rate product and long transmission distances of passive and active optical communication networks, wireless communication, radio over fiber communication systems, and optical network security and management.

Continuous processes in the plastics, textile paper and other industries, require several drives ... more Continuous processes in the plastics, textile paper and other industries, require several drives working in synchronism. The aim of this paper is to control speed of the winding system, and to maintain a constant mechanical tension between the rollers of the system. Several controllers are considerer, including sliding-mode control (SMC) single input/single output (SISO) and SMC multi input/multi output (MIMO) and Proportional-integral (PI/MIMO) . Since the PI control method can be applied easily and is widely known, it has an important place in control applications. But this method is insensitive to parameter changes. The advantage of an SMC is its robustness and ability to handle the non-linear behaviour of the system. The main contribution of this paper consists of designing MIMO sliding mode control law of a distributed parameter based on the original model for which the control variables are coupled. The performances of the control law are illustrated by means of simulations and compared to previous results obtained by SISO and (PI-MIMO) control laws.