Applied Mechanics and Materials Vol. 573

Abstract: In a deregulated electricity market, it is important to dispatch the generation in an economical manner. While dispatching it is also important to ensure security under different operating conditions. In this study intelligent technique based solution for optimal power flow is attempted. Transmission cost is calculated using Bialek’s upstream tracing method. Generation cost, transmission costs are combined together for pre and post contingency periods to form objective function. Different bilateral and multilateral conditions are considered for analysis. A human group optimization algorithm is used to find the solution of the problem. IEEE 30 bus system is taken as test systems.

Abstract: Power system load growth is increasing at a faster rate than the increase in the transmission capability. Transmission congestion occurs when the transmission system is incapable of servicing a load request even if the generation stations are capable of providing it. This paper demonstrates the operation of Thyristor Controlled Series Capacitor for optimization of transmission and thereby, reducing the transmission congestion. A genetic algorithm is developed to optimize a factor, Performance Index (PI) for the contingency analysis, involving both the location and control of TCSC. These devices enhance the transfer capability, minimize the total power loss in a system thereby, improving the system efficiency.

Abstract: Application of Flexible AC Transmission Systems (FACTS) devices in a power system is a promising and more efficient way for the transfer and control of bulk amount of power. One of the problems encountered in power-systems operation is the generation of unbalanced voltages and currents in the presence of long transmission lines with few or no transpositions. This includes possible unbalances arising in source and load conditions, or indeed any items of plant such as shunt and series reactors. To improve or investigate these unbalance effects in any detail, a 3-phase load-flow solution that allows representation of all possible unbalances as they exist in the power-systems network without making any assumptions is essential. This paper deals with the three phase power flow incorporating Static Var Compensator (SVC). Here SVC is modeled using variable reactance modeling technique and incorporated into the single phase and three phase load flow. Newton Raphson power flow algorithm is adopted here. The performance of SVC to control the power flow and regulating voltage in the network is discussed. The performance analysis is carried out for 4 case studies namely single phase power flow, single phase power flow with SVC, three phase power flow and three phase power flow with SVC. The change in power flow and losses due to the unbalanced load condition in the three phases in illustrated. The studies are carried out in a standard 5 bus test system. Keywords: Three Phase Power flow, Static Var Compensator, Unbalanced system, Negative sequence components, Zero sequence components.

Abstract: This paper attempts an investigation of the potential area of the standalone hybrid (solar and wind) renewable energy source. The investigation are based on the optimization result and ranking status. The various coastal areas identified for this are Kilakarai, Mandapam, Thirupullani, Kadaladi and Rameswaram in Ramanathapuram District of Tamilnadu State, India. The sensitivity analysis is also conducted. The consumer demand data are collected through the local distribution agency for the identified coastal areas. The wind and solar resources data are collected from NASA’s surface meteorology and solar energy resource. HOMER has been used in this paper for optimization result and for sensitivity analysis. The preliminary investigation indicates that Thirupullani area is the potential area for standalone hybrid renewable energy system among the five coastal areas identified. By the sensitivity analysis, it is proved that the cost of energy, net present cost and operating cost was reduced to half of the actual cost, except the capacity shortage in Thirupullani area.Keywords: Solar and Wind Energy, HOMER, Potential Analysis, Ranking Status

Abstract: – This paper presents a new method for identifying the best switching option for the reconfiguration of Radial Distribution Systems (RDS). Feeder reconfiguration is the technique to alter the topological structure of the distribution feeder by changing the open/close status of sectionalizing and tie switches. The reconfiguration involves in selection of the set of sectionalizing switches to be opened and tie switch to be closed such that the resulting RDS has the desirable performance. Amongst the several criteria considered for optimal network configuration, loss minimization criterion is very widely used. In this project a novel method is presented which utilizes feeder reconfiguration as a planning and real time control tool in order to restructure the primary feeders for the loss minimization. The mathematical formulation of the proposed method is given; the solution procedure is illustrated with an example. Owing to the discrete nature of the solution space, a neural network approach for optimal reconfiguration of distribution network is proposed.

Abstract: Uneven terrains in mountain regions, where wind mills are to be erected cause concerns on the matrix of location, variation in wind direction, wake effects and due to location which may take a toll on efficiency, frequent changes in wind velocity, limitation of the hub height are a fear of the exogenous variables that influence the operation of wind farm. An attempt is made in this work to analyze the effect of those parameters on the efficiency of wind farm. Energy efficiency and exergy efficiency for a three column wind farm are determined and compared. The mathematical model developed considers wake deficit loss, transmission losses and resource losses the loss due to change in the wind direction, overall efficiency factor and locational specifications. A new objective function is derived for the wind farm with multidirectional wind flow and it is solved by Covariant Matrix Adaptation Evolutionary Strategy algorithm. This algorithm is used to maximize the wind farm exergetic efficiency. Location specification is the main variable to optimize and the other dimensionless variables remain same. Exergy efficiency is improved when compared to the reference layouts. The results projected will help the wind farm promoters to optimally utilize the resources to get maximum output.

Abstract: Volatile organic compounds (VOCs) are organic chemicals that encompass a high vapour pressure .The VOCs are numerous and varied. In breath the concentration of VOCs ranges from parts per million to parts per trillion. The discovery of VOCs in breath is used as a diagnostic tool for many diseases, disorders and metabolic studies. So far these gases have been identified using gas chromatography (GC) which is time consuming and expensive technique. With the introduction of sensors as frontend to detect vapour signals, the work can be processed easier. This article proposes a system for breath analysis using tin oxide semiconductor gas sensors, in which the conductivity changes depending on the concentration of the vapour. A prototype model was developed to detect the presence of acetone in the breath, which is a biomarker for diabetes mellitus. This study has been helpful in designing an electronic nose for detecting other vapours like benzene, ammonia and Nitric oxide which are the biomarkers for lung cancer, renal disorder and asthmatic inflammation.

Abstract: : Diabetic Maculopathy (DM), the most common eye disease of the diabetic patients, arises once a small blood vessel gets impaired in the macula, due to high glucose level. It affects the patients who have diabetes for more than 5 years, which can also prime to vision loss. Recognition of diabetic maculoathy in advance, protects patients from vision loss. The major symptom of diabetic maculopathy is the presence of any lesions. Detecting macula diseases in an initial stage, supports the ophthalmologists apply accurate treatments that might eliminate the disease or decrease the severity of it. This paper focuses diabetic maculopathy identification through detecting lesions by extracting features through GLCM in colour fundus retinal images and also classifies the meticulousness of the lesions. Decision making of the harshness level of the infection was performed by KNN classifier

Abstract: Electromyography (EMG) has been widely used as a tool to understand and distinguish between normal and pathological gait. This study aims at understanding the activation patterns of lower limb muscles viz. Gastrocnemius and Tibialis Anterior in the dominant leg of subjects with normal (n=5) as well as pathological (n=2) gait patterns. The paper presents a normative pattern of these muscles during normal walking condition from which the deviation of affected group from the control group is observed. For this analysis, Surface EMG signals along with Force Sensitive Resistor values are acquired. These surface EMG signals picked up during the muscle activity are interfaced with a PC via EMG acquisition system. The acquired signals were processed and analyzed which can be used for rehabilitative therapy planning.

Abstract: Ultrasound is an important diagnostic tool in distinguishing interfaces between soft tissues, especially abdominal structures. Diagnostic ultrasound is used for the detection of cysts, tumors or cancers present in the abdomen. Bladder cancer is one of the common types of cancer nowadays. The volume of the bladder is less in case of presence of cyst, tumors or cancers. Considering the importance of measurement of volume of the urinary bladder, various invasive and noninvasive methods are discussed in this article. The invasive method has many disadvantages. Hence this article encompasses the various noninvasive methods and its implementation using imaging techniques are discussed. The imaging techniques include Prolate Ellipsoid Method, Double Area Method and Double Ellipsoid Method. The methodology which is being generally used to calculate the volume of the urinary bladder is Prolate Ellipsoid Method. The accuracy of the above mentioned methods is reported with relatively larger errors of about 60%. The accuracy can be increased by incorporating sophisticated, expensive 3D software packages and imaging tools.