iosr-JEEE   Volume-2 ~ Issue-2

Abstract: Energy losses occur in the process of supplying electricity to consumers due to technical & commercial losses. The technical losses are due to energy dissipated in the conductors and equipment used for transmission, transformation, sub-transmission and distribution of power. These technical losses are inherent in a system and can be reduced to an optimum level. The system load factor of the Karnataka State Electricity Board (KEB) during 2009-10 was 70%, which is considerably low; It is worthwhile to make a study of the effect of system load factor on transmission & distribution loss reduction & the consequent increase in profitability of power utilities, with a focus on the Karnataka system. The study shows how the annual savings can be achieved through improvement of load factor.
Keywords: T & D losses, Load factor, Annual Savings, Reduction in T & D Loss, Load Factor on profitability

[1] KEB, Annual Administration Report 2009-2012 of Karnataka state Electricity Board, Bangalore, India.
[2] SRPC, Annual Report 2009-2012 of Southern Region Power Committee, Bangalore, India. (under CEA). www.srpc.kar.nic.in.
[3] SIEMENS (1981) Electricity Engineering Handbook, New Delhi, India: New Age International Private Limited.
[4] Economic Survey of Karnataka state, 2009-2012.

Abstract: This article briefly discuses the types and effects of hearing loss and then focuses on the topic of cochlear implants. The history of such devices is reviewed, as are their components and functions. Selection criteria for adult and pediatric implant candidates are outlined, and the procedures, risks, follow up, and likely outcomes of surgery are examined. The controversial issue of providing implants to children also addressed.

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Abstract: Generally, the Power systems are subjected to a wide range of disturbances, small and large. For small disturbances, load frequency and excitation voltage control problems are non interactive. In the large interconnected power system, it is also desirable to maintain the tie- line power flow at a given level irrespective of load changes in any area. Therefore there is a need to go for automatic controlling equipment (called Automatic Generation Control) which regulates the changes in frequency and the tie line power so as to meet the changing demands. The AGC system solely cannot control the disturbances, it need another controller like proportional integral (PI), proportional integral derivative (PID) controller. PI controller is simple for implementation but takes more time and gives large frequency deviations. Large disturbance is concerned with the ability of the power system to maintain synchronism when subjected to a severe disturbance, such as a short circuit on a transmission line. In general rotor angle stability is taken transient stability of power system, which is the function of operating condition and disturbances. In order to improve the Transient Stability margin, FACTS devices has been implemented. In this paper, the transient stability improvement is verified using Simulink, with different FACTS devices, namely Static Var Compensator (SVC) and Static Synchronous Compensator (STATCOM). It has been observed that the FACTS devices, when placed slightly off-centre towards sending-end, gives better performance in improving transient stability and the location depends on the amount of local/through load. The results are experimented and simulated on MATLAB/Simulink environment.
Keywords: AGC, Conventional controller, Inter area power system, FACTS devices, SVC, STATCOM

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Abstract: The ability to harvest energy from the environment represents an important technology area that promises to eliminate wires and battery maintenance for many important applications and permits deploying self powered devices. This paper suggests the Application of Charging Mobile Phone by solar energy. In the beginning, a comprehensive overview to the energy harvesting concept and technologies is presented. Then the Application of Charging Mobile Phone by solar energy its efficiency to charge the aimed batteries under sunlight or an indoor artificial light

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Abstract: In this paper, a new method of minimizing the input current total harmonic distortion (THD) as well as power factor by using a chain inverter to replace a traditional inverter is presented. This proposal is verified through simulation which uses one type of DC to AC converter with 3-links which can be used to generate seven level output voltage by connecting a number of similar Insulated Gate Bipolar junctions Transistor (IGBT) in series, to form a high Voltage- Source-Inverter (VSI). The main feature of this topology is low cost, small size, high efficiency and simplicity, and is excellent for existing ac drives, UPS etc. A new method of implementing stepped voltage waveform proposed here is based on the operation principle of Chain link converter. With reference to the control algorithm, this strategy has realized for seven-level inverter which generates high quality sinusoidal voltage contains lower THD. During one cycle, each IGBT of a CLI switches 'ON/OFF' for a certain time and period using a Sinusoidal Pulse Width Modulation (SPWM) technique. This SPWM technique uses two triangular carrier bands – one positive and one negative – per link, and has a carrier frequency of twice the fundamental frequency and one modulating signal for all links. Simulation is carried out by using MATLAB/SIMULINK which confirms the feasibility of the proposed system.
Keywords: Chain Link Converter, Sinusoidal Pulse Width Modulation, VAR,SVC.

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Abstract: The proposed method develops a fuzzy rule-based classifier that was tested using features for islanding detection in distributed generation. In the developed technique, the initial classification boundaries are found out by using the decision tree (DT). From the DT classification boundaries, the fuzzy member- ship functions (MFs) are developed and the corresponding rule base is formulated for islanding detection. But some of the fuzzy MFs are merged based upon similarity the measure for reducing the fuzzy MFs and simplifying the fuzzy rule base to make it more transparent. The developed fuzzy rule-based classifier is tested using features with noise up to a signal-to-noise ratio of 20 dB and provides classification results without misdetection, which shows the robustness of the proposed approach for islanding detection for distributed generations in the distribution network.
Index Terms - Decision tree, fuzzy rule base, islanding detection, similarity measure.

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Abstract : This paper presents a transient stability improvement using neural-fuzzy controller design for STATCOM with static synchronous time critical error and better damping system oscillations after a short circuit fault. This article on a STATCOM Control for transient stability improvement has proposed a system to meet with the addition of Lyapunov stability criterion to the ability and conditions as well. The performance is analyzed using digital simulation with SMIB.
Keywords – Fuzzy Logic, Neural Network, lyapunov energy function, STATCOM, transient stability

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