iosr-JEEE   Volume-6 ~ Issue-1

Abstract: Power is generated in generating station, transmitted through transmission line and then distributed to consumers.Power system consists of three types of buses. They are generator bus, load bus and slack bus. Each bus is characterized by four parameters. They are bus voltage, phase angle, active power and reactive power. Thesebuses are classified according to known parameters. Unknown parameters are found using load flow studies. In this paper load flow studies are done using Newton-Raphson method. Transmission line is characterized by resistance, inductance and capacitance. This will result in losses. These losses cannot be eliminated but can be reduced.Optimization is a mathematical tool to find the maximum or the minimum of a function subject to some constrains. Using lose function as objective functionsubjected togenerator MW, transformer tapping, reactive power injection and controlled voltage as constrains, optimization technique can be used to minimize transmission losses. Using this we get optimal value for bus parameters such that transmission losses are minimum. In this paper Particle Swarm Optimization (PSO) is employed to solve optimal power flow problems. IEEE 30-bus power systems are used for testing the objective of this paper.

Keywords: Optimal Power Flow (OPF),Penalty factor, Newton-Raphson method,Power Loss Minimization, Particle Swarm Optimization (PSO),Gbest, Pbest

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[2] B. Zhao, C.X. Guo and Y.J. Cao, \Improved particle swam optimization algorithm for OPF problems," IEEE-PES Power Systems Conference and Exposition, Vol. 1, pp.233 - 238, 10-13 October 2004.

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[4] R.N. Banu and D. Devaraj, \Optimal Power Flow for Steady state security enhancement us- ing Genetic Algorithm with FACTS devices," 3rd International Conference on Industrial and Information Systems, pp. 1 6, 8-10 December 2008.

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[6] C. Gonggui and Y. Junjjie, \A new particle Swarm Optimization Solution to Optimal reactive power Flow Problem," Asia-Paci¯c Power and Energy Engineering Conference, pp.1 4, 27- 31 March 2009."

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[8] W. Cui-Ru, Y. He-Jin, H. Zhi-Qiang, Z. Jiang-Wei and S. Chen-Jun, "A modi¯ed particle swarm optimization algorithm and its application in optimal power flow problem," International Conference on Machine Learning and Cybernetics 2005, pp. 2885 2889, 18-21 August 2005.

[9] S. M. Kumari, G. Priyanka and M. Sydulu , \Comparison of Genetic Algorithms and Particle Swarm Optimization for Optimal Power Flow Including FACTS devices," IEEE Power Tech 2007, pp. 1105 - 1110, 1-5 July 2007.

[10] C. Chokpanyasuwant, S. Anantasate1, S.Pothiya ,W. Pattaraprakom and P. Bhasapu-tra1, "Honey Bee Colony Optimization to solve Economic Dispatch Problem with Generator Constraints," ECTI-CON 2009. 6th Internaional Conference, Vol. 1, pp. 200 203, 2009.

Abstract: This paper proposes Fuzzy Logic Based STATCOM. It regulates the voltage at the point of common coupling (PCC) by injecting reactive power. This device also plays a vital role in enhancing stability for small and large transient disturbances in power system. Simulations using MATLAB / SIMULINK are carried out to verify the performance of STATCOM using fuzzy controller. The result shows that fuzzy logic controller is a better choice for the STATCOM compared to the PI controller. Fuzzy logic controller forces the system to return back the steady state value faster than the PI controller. The fuzzy logic controller is robust and has a fast response during disturbance and parameters variation. Detailed study of control of STATCOM has been made, which include analysis of PLL, VSC, mathematical dq transformation has been explained.

Keywords–Static Synchronous Compensator (STATCOM), Pulse-Width Modulation (PWM), Fuzzy logic controller (FCL), PLL, Regulator,abcto dq transformation, Voltage Source Converter (VSC)

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Abstract: The trend in Nigeria is shifting from providing electricity to consumers only but with improved quality as a result of deregulation. This paper demonstrates the adaptability of distribution automation system to electric power quality on-line monitoring using Nigeria distribution system as a case study. This paper reviews power quality problems, electric power distribution topology and monitoring quantities. The paper explains the development of program for the analysis of power quality. Sensors were incorporated at the substations for the measurement of substation voltages and line currents. The embedded system coordinates the activities of these sensors and initiates communication at regular intervals with the central server for analysis. The data back-up was implemented on external card which are available for down load on monthly basis. The results reveal neglect to the issues of quality, failure to comply with regulations in some of the substations investigated. The study is expected to benefit the operator in the area of planning and improved power delivery.

Keywords: Current, Distribution Automation, Power Quality and Voltage

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[4] Umar N K, (2007) Signal Processing Techniques used in Power Quality Monitoring Faculty of Electrical Engineering, Wroclaw University of Technology, Poland

[5] Styvaktakis E., Bollen M. H. J., Gu I.Y.H, (2002), "Automatic classification of power system events using RMS voltage measurements", IEEE Power Engineering Society Summer Meeting, vol.2, pp. 824- 829

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[10] R. P Gupta Distribution Automation System, Indian Institute of Technology Gupta Kanpur –pg16 2008