Vol 2 Issue 2 May 2015-August 2015

Abstract: To overcome the challenges of multi-frequency operation a new scheme of multiband is proposed. This paper proposes a microstrip patch antenna for multiband operations. This antenna shows the three distinct frequency bands, centered at 12.5 GHz, 14.55 GHz and 16.7 GHz. The proposed antennas has compact size of 19 X 19 X 1.07 mm3 including the ground plane and both antenna structures are designed on FR-4 substrate (εr= 4.5) of thickness h=1 mm. The proposed structure is simulated using the electromagnetic (EM) simulation software. The simulated return loss is less than -20dB at resonante frequencies. The presented antenna is suitable for multiband wireless communication systems.

Abstract: Load forecasts are extremely important for energy suppliers and other participants in electric energy generation, transmission, distribution and markets. Forecasting means estimating active loads at various load buses ahead of actual load occurrence Planning  and operational applications of load forecasting  requires a certain “lead time’’ also called forecasting intervals. This paper presents an application of adaptive neuro-fuzzy inference system(ANFIS) and this paper presents prediction of electric load by considering different factors like time, day of the week and temperature. Historical load data are collected from the State Load Dispatch Center Jabalpur and weather data are collected from website  www.worldweatheronline.com .From the analysis carried out on the ANFIS-based model; Mean absolute percentage error (MAPE) for a typical Wednesday (24th Dec. 2014) was found to be 3.07266.

Abstract: The main objective of the proposed system is to provide uninterruptible power supply to the load systems.  The proposed system mainly deals with the implementation of the Energy Management System (EMS) to the DC microgrid Applications, which consists of the hybrid power sources and storage system.  The power sources employed in the system, which obtains its power from the PV panels, and fuel stacks.  The storage system employs battery, and the EB system acts as a standby source, which is committed during the power failure condition.  The EMS consists of the RS 485 and ZigBee communication protocol for the purpose of communication.  The EMS incorporates the fuzzy control, has two roles Energy Management, and battery management.

Abstract: In this paper we used wavelet transform which is useful in signal processing. Wavelet transform is used for analyze different power quality events. The power quality events like pure sine voltage wave, voltage sag, swell, harmonics, impulse can obtained using wavelet transform. The wavelet algorithm is a useful tool for signal processing. Fourier transform is also used for denoising but limited to stationary signals .For continuous analysis of non-stationary signals wavelet transform is used. The presence of noise can be detected by wavelet methods and analyze the noisy signal. The noisy signal can be denoised using wavelet transform.

Abstract: In this review paper, we. Propose a Hidden Markov Model (HMM)-based iris  recognition system and. The person is identified using 7- state HMM as classifier and Singular Values Decomposition (SVD) coefficients as features for iris recognition. Using quantized SVD as feature describing blocks of the image, each iris is considered as a numerical sequence that can be easily modeled by HMM.

Abstract: Wind energy is said to be one of the most prominent sources of electrical energy in years to come. The increasing concerns to environmental issues demand the search for more sustainable electrical sources.. Wind power has to overcome some technical as well as economic barriers if it should produce a substantial part of the electricity. In this paper, some of the technical aspects are treated, particularly those regarding the power system quality and stability. In the late 90’s till date, with the wind farms rating hundreds megawatts, the concerns start to focus on the transient voltage stability of the power system. During the same period an International Electro-technical Commission (IEC) task force issued a standard procedure: the IEC 61400-21[1] to fill-in the lack of technical standards on assessment of power quality from wind turbines.

Abstract:  Electric load forecasting is a real-life problem in industry. This report presents the development of an Adaptive Neuro Fuzzy Inference System (ANFIS) based short-term load forecasting model which forecast the electric load. This report presents prediction of electric load by considering various information like time, temperature and historical load data. Historical load data is taken from MPEB Jabalpur and weather data is taken from the website www.worldweather online.com. ANFIS is a class of adaptive networks that are functionally equivalent to fuzzy inference systems. The prime inherent advantage associated with the soft computing techniques of not requiring a mathematical model has been a motivating factor for consideration in our present work. Motivated by this advantageous feature of soft computing based load forecasting, the present work focuses on building a model for an ill-defined real world system based on its available record of input-output data using ANFIS. From the analysis carried out on the ANFIS-based model; Mean absolute percentage error (MAPE) for a particular Tuesday was found to be 5.705 %. Results and forecasting performance obtained reveal the effectiveness of the proposed approach and shows that it is possible to build a high accuracy model with less historical data using a combination of neural network and fuzzy logic which can be used in real time.

Abstract: This paper presents the MATLAB (PSAT) simulation of an IEEE 14 bus system to compute the load flow solution by using Newton Raphson method. L-index method is used as the measuring unit in predicting the voltage stability condition in the system. The SVC is a shunt device of the FACTS groups widely used to efficiently utilize the existing power system and to enhance the stability of the power system.

Abstract: The Dynamic voltage restorer is custom power device which is utilized to mitigate the voltage at load terminals. Power quality is one of major concerns in the present era. It has become important, especially, with the introduction of sophisticated devices, whose performance is very sensitive to the quality of power supply. Power quality problem is an occurrence manifested as a nonstandard voltage, current or frequency that results in a failure of end user equipments. One of the major problems deal at here is the power sag. To solve this problem, custom power devices are used. One of those devices is the Dynamic Voltage Restorer (DVR), which is the most efficient and effective modern custom power device used in power distribution networks. DVR injects required voltage in series with supply voltage through injection transformer for correcting voltage amplitude, phase and harmonic component into line. This paper presents development, simulation and analysis of a Dynamic Voltage Restorer (DVR) using MATLAB/ SIMULINK. To enhance the voltage sag restoration capability of the DVR, this paper deals with the development of a control structure using a Discrete PWM pulse generator.  This paper discussed abc to dq0 based new control algorithm to generate the pulse. Results obtained shows that the developed DVR has good capability to starch the voltage level during voltage sag conditions.

Abstract: At atmospheric pressure the di-electric strength of SF6 is about 2.5 times that of air. Thus uses as a insulating medium in high voltage electric devices. Since SF6 is used as a good insulating material but it has many disadvantages. It is not found in abundant quantity, it is poisonous, and also SF6 gas is classified as a greenhouse gas. In order to overcome the above disadvantages of SF6 gas it is found the substitution of SF6 gas known as “DRY AIR “having breakdown strength approximately same as SF6.

Abstract: This paper aim is to design a controller for controlling the Temperature Heat Exchanger process of a plant .The effects of the controller on heat exchanger is analyzed .Automatic tuning of the controller is also introduce for efficient control of the process .The tuning is implemented using Ziegler Nichols method and results are compared with Variation in temperature without controller.

Abstract: Transmission and distribution power network use insulator between line conductor and support structure. Most of the insulator is mounting in open air applications. So gradually contamination is deposited on the surface of insulator and reduce the voltage withstand capacity of insulator. This hampers the reliable operation of power network. Hence condition monitoring of insulator is needed in order to maintain smooth and uninterrupted power supply. Leakage current helps in determining meaningful information about contamination and flashover capacity of insulator. Considering the above mentioned fact an experimental setup has been made in the laboratory according to IEC 60507 for artificial pollution test on high voltage insulator. The effect of different level of salt contamination on 33KV porcelain and polymer insulator is being observed.

Abstract: Direct torque control (DTC) is a method to control machine with utilizing torque and flux of motor controlled. In recent years Permanent Magnet synchronous motors (PMSMs) are used in many applications that require rapid torque response and high-performance operation. PMSM has no damper windings and excitation is provided by a permanent magnet instead of a field winding. The elimination of field coil, dc supply and slip rings reduce the motor loss and complexity.
It is mathematically proven that the increase of electromagnetic torque in a permanent magnet motor is proportional to the increase of the angle between the stator and rotor flux linkages, and, therefore, the fast torque response can be obtained by adjusting the rotating speed of the stator flux linkage as fast as possible. This is achieved by using direct torque control (DTC) technique. This paper introduces the principle of space vector pulse width modulation (SVPWM) ,and closed loop speed control technique namely Direct Torque Control for Permanent Magnet Synchronous Motor Drive.

Abstract: Renewable energy resources, such as wind, solar and hydropower, offer clean alternatives to fossil fuels. They produce little or no pollution or greenhouse gases, and they will never run out. Generating electricity from renewable sources is more expensive than conventional approaches, but reduces pollution externalities. Analyzing the tradeoff is much more Challenging than often presumed, because the value of electricity is extremely dependent on the time and location at which it is produced, which is not very controllable with some renewables, such as wind and solar. Likewise, the pollution benefits from renewable generation depend on what type of generation it displaces, which also depends on time and location. Without incorporating these factors, cost-benefit analyses of alternatives are likely to be misleading. However, other common arguments for subsidizing renewable Power – green jobs, energy security and driving down fossil energy prices – are unlikely to substantially alter the analysis. The role of intellectual property spillovers is a strong argument for subsidizing energy science research, but less persuasive as an enhancement to the value of installing current renewable energy technologies.

Abstract: Visual observations of arcing and audible corona are the first indications that signal changes to the coating have taken place. It emphasizes that in the absence of reliable data one can use observations based on hydrophobicity to evaluate when maintenance or replacement of the coated insulators is necessary. Life extension strategies are suggested. It also demonstrates that there are differences in the hydrophobicity characteristics among commercially available coatings, and these can be quantified using standard laboratory techniques. Field experience suggests that the life of the RTV coatings can exceed 10 years even under the severest conditions of pollution.