iosr-JEEE   Volume-6 ~ Issue-2

Abstract: This paper presents design and analysis of a three phase induction motor drive using IGBT‟s at the inverter power stage with volts hertz control (V/F) in closed loop using a microcontroller. A 1HP, 3-phase, 415V, 50Hz induction motor is used as load for the inverter. Oscilloscope is used to record and analyze the various waveforms. The experimental results for V/F control of 3-Phase induction motor using GSM clearly shows constant volts per hertz and stable inverter line to line output voltage.

Keywords - Induction motor, IGBT, GSM,V/F,PWM technique

[1] Alfredo,Thomas A. Lipo And Donald W. Novotny, "A New Inductio Motor V/F Control Method Capable Of High-Performance
Regulation At Lowspeeds" IEEE Trans. Industry Applications, Vol. 34, No. 4 July/ August 1998.
[2] B. Biswas, S. Das, P. Purkait, M. S. Mandal And D. Mitra," Current Harmonic Analysis Of Inverter-Fed Induction Motor Drive
System Under Faultconditions", International Conference Of Engineers And Computer Scientists 2009 Vol II IMECS 2009
[3] Ku. Trupti Deoram Tembhekar "A Constant V/F Open Loop And Closed Loop Speed Control Of A Three Phase Induction Motor
Drive"
[4] Masayuki Morimoto, Kiyotaka Sumito, Shinji Sato, Katsumi Oshitani, Shigeru Okuma" High Efficiency, Unity Power Factor VVVF
Drive System Of An Induction Motor" IEEE Transactions On Power Electronics. Vol 6.No.3.July 1991.
[5] Lu, Willie W, Open Wireless Architecture and Enhanced Performance, Guest Editorial, IEEE Communication Magazine, June 2003
[6] Rodolfo Echavada, Sergio Horta, Marc0 Oliver, "A Three Phase Motor Drive Using IGBT‟S And Constant V/F Speed Control With
Slip Regulation", 0-7803-3071-4/95 1995 IEEE
[7] Rashid M.H, Power Electronics-Circuits, Devices And Applications", Third Edition Printice Hallindia,2001.

Abstract: In this paper, the simulation model of a typical canal type small hydroelectric power plant was developed through interconnection of models of various equipments of the plant under consideration in a MATLAB/Simulink based software environment. The various components of small hydroelectric plant like open channel, governor and Semi-Kaplan turbine, synchronous generator, exciter are being considered under modeling and simulation.. The aim is to study its behavior during transient condition. Using the simulated model enhancement through PID controller will be done to reduce oscillations, peak overshoot and peak undershoot during transient period and also to improve the steady state response This study helps in verifying costs and safety conditions, in selecting the best alternatives in the early phase of design and to determine the requirements of special protection devices.

Keywords – Hydraulic Transients, mathematical models, proportional and integral controller, small hydro electric power plants, Matlab/Simulink.

[1] Carmen L.T. Borges, Senior Member, IEEE, and Roberto J. Pinto. Small Hydro Power Plants Energy Availability Modeling for Generation Reliability Evaluation. IEEE TRANSACTIONS ON POWER SYSTEMS, VOL. 23, NO. 3, AUGUST 2008.
[2] National Association of State Energy Officials (NASEO). Web site: www.naseo.org
[3] Micro-hydro. Web site: www.geocities.com/wim_klunne/hydro/index.html

[4] U.S. Department of Energy Hydropower Program. Web site: hydropower.inel.gov
[5] Volunteers in Technical Assistance (VITA). Web site: www.vita.org
[6] Energy Efficiency and Renewable Energy Clearinghouse (EREC). Web site: www.eren.doe.gov/consumerinfo/.

[7] Prabha Kundur, Power System Stability and Control by Tata McGraw-Hill, New York. A Power System Engineering Series.

[8] Paul M. Anderson and A.A. Fouad Power System Control and Stability IEEE PRESS. The Institute of Electrical and Electronics Engineer, Inc., New York.

[9] K.R.Padiyar, Power System Dynamics-Control and Stability, Interline Publishing Pvt. Ltd., Banglore.

[10] Hongqing Fang, Long Chen, Nkosinathi Dlakavu, and Zuyi Shen Basic Modeling and Simulation Tool for Analysis of Hydraulic Transients in Hydroelectric Power Plants. IEEE Transactions on Energy Conversion, Vol. 23, No. 3, September 2008

Abstract: Increasing demand of electrical energy and its rising prices have enforced the need of managing usage of electrical energy more efficiently. This requires regular monitoring of electrical appliances to timely identify inefficient energy consumption due to faulty conditions, inefficient designs, user negligence, etc. In this paper, design and development of a low-cost wireless data logger is presented that aims to accurately measure the value of energy and related parameters like VRMS, IRMS and instantaneous power in real time for single phase applications. The proposed data logger acts as a plug-in device that can easily be introduced between mains and the appliance. The system can collect the data in real time and communicate it to a computer over a Bluetooth based wireless link. The computer hosts a simple graphical user interface (GUI) based application that allows user to log the data as and when required. The proposed data logger is designed using CS5460A single phase bi-directional power/energy IC from Cirrus logic interfaced with AVR ATmega32 microcontroller. A wireless link between is established using AUBTM-20 Bluetooth modules. Serial EEPROM is also included in the proposed design to store the data locally on the board for later use. GUI for the data logger has been designed using MATLAB.

Keywords - Bluetooth , Data logger, Energy monitoring, , Embedded system, Real time monitoring

[1] S. M. Ahluwalia, Power sector reforms: a review of the process and an evaluation of the outcome, NCAER, Delhi, March 2000.
[2] Energy monitoring technologies inc., 2011, http://www.energymonitor.com
[3] X. Jiang, S. Dawson, P. Dutta, and D. Culler, Design and implementation of high-fidelity ac metering network, Proc. of IEEE Int. Conf. on Information Processing and Sensor Networks, California, USA, 2009.
[4] S. Keshav and C. Rosenberg, How internet concepts and technologies can help green and smarten the electric grid, Green Networking 2010, New Delhi, India, 2010.
[5] Y. Kim, T. Schmid, Z. M. Charbiwala,, and M. B. Srivastava Smith, Design and implementation of a fine grained power monitoring system for homes, Networked & Embedded System Lab., 2009.
[6] Shum-Yu Chan and Jen-Han Teng H. Miller, Advance remote control infrastructure for intelligent HEMS, Proc. of Int. Conf. on Infomration and Electronics Engg., Singapore, 2011.
[7] D. D. Vyas and H. N. Pandya,Advance metering infrastructure and DLMS/COSEM standards for smart grid - A review, Int. Journal of Engg. Research and Tech., Vol. 1, No. 2, Nov. 2012.
[8] The home area network architectural considerations for rapid innovation, Penn Energy, 2009, http://www.pennenergy.com.
[9] CS5460A- Single phase bi-directional power energy IC Data Manual, Cirrus Logic.
[10] AVR ATmega32 Microcontroller Data Manual, Atmel Corporation.

Abstract: This paper describe about the optimization of economic loading dispatch (ELD) problem. Economic loading dispatch is one of the important optimization tasks which provide economic condition for a power system. The ELD problems have non-smooth objective function with equality and inequality constraints. This paper presents particle swarm optimization (PSO) method for solving the economic dispatch(ED) problem in power system. The particle swarm optimization is an efficient and reliable evolutionary computational technique, which is used to solve economic load dispatch with line power flows. This paper describes, a new PSO framework used to deal with the equality and inequality constraints in ELD problem. The proposed PSO can always provide satisfying results within a realistic computation time. The PSO is applied with non-smooth cost function. The six thermal units, 26 buses and 46 transmission lines system is used in this paper. The proposed PSO method results are compared with the genetic algorithm (GA) and conventional method to show the effectiveness of PSO method to solve the ELD problems in power system.

Keywords- Economic load dispatch, generating unit, genetic algorithm, power system, loss minimization, particle swarm optimization.

[1] S.G. Soni, and Dr. M. Pandit, "Hybrid PSO based optimization of emission and economic load dispatch problem," Proceedings National Conference on Advances in Power Systems and Energy Management, May 6-7, 2009, pp 462-467.

[2] G.N. Ajah, and B.O. Anyaka, "Optimization methods and algorithms for solving of hydro-thermal scheduling problems," IOSR Journal of Electrical and Electronics Engineering, Volume 5, Issue 3, Mar. - Apr. 2013, pp. 68-75.

[3] Nagendra Singh, and Yogendra Kumar, "Economic load dispatch with valve point loading effect and generator ramp rate limits constraint using MRPSO," International Journal of Advanced Research in Computer Engineering & Technology(IJARCET), Volume 2, Issue 4, April 2013, pp 1472-1477.

[4] S.G. Soni, M. Pandit and L.Shrivastava, "Particle swarm optimization technique for solving economic dispatch problem of large power system," National Conference on Advances in Power Systems and Energy Management, March 1- 2, 2008.

[5] Jong-Bae Park, Ki-Song Lee, Joong-Rin Shin, and Kwang Y. Lee, "Economic load dispatch for non-smooth cost functions using particle swarm optimization," IEEE 0-7803-7989-6/03/$17.00, 2003, pp 938-943.

[6] Jin S. Heo, Kwang Y. Lee, and Raul Garduno-Ramirez, "Multi-objective control of power plants using particle swarm optimization techniques," IEEE Transactions on Energy Conversion, Vol. 21, No. 2, June 2006, pp. 552-561.

[7] A.Zaraki, and M.F.Bin Othman, "Implementing particle swarm optimization to solve economic load dispatch problem," International Conference of soft computing and Pattern Recognition, 2009, DOI 10.1109/SoCPaR.2009, 24.

[8] M.A.Abido, "Optimal power flow using particle swarm optimization" ELSEVIER, 2001, pp.563-571.

[9] Jong-Yul-Kim, Kyeong-Jun Mun, Hyung-Su Kim, and June Ho Park, "Optimal power system operation using parallel processing system and PSO algorithm," International Journal of Electrical Power and Energy System, Vol. 33, 2011, pp. 1457-1461.

[10] Vivek Kumar Jain, and Himmant Singh, "Hybrid particle swarm optimization based reactive power optimization," International Journal of Computational Engineering Research, ISSN: 2250-3005

Abstract: Steady state and transient problems in a power system have undesirable consequences on the system. It can limit the amount of power that can be transmitted in the system and consequently leads to voltage instability and at times it may also result into total voltage collapse.The main objective of this paper is a comparative investigate in enhancement of volatge stability via static synchronous series compensator (SSSC) and static var compensator (SVC) externally controlled by a POD controller.The new designed P.O.D controller is very efficient for voltage stability under transient conditions. This paper discusses and demonstrates the comparision between the SVC with P.O.D controller and SSSC with P.O.D controller,applied to power system for effectively regulating system voltage for different types of faulted condition. One of the major reasons for installing a SVC is to improve dynamic voltage control and thus increase system load ability during transient condition. This work is presented to present the transmission line voltage stability & machine oscillation damping stability by using SVC & SSSC with POD controller & compared their performance to enhance the stability of a power system. Simulation results shows that SVC with POD controller is more effective to enhance the voltage stability and increase transmission capacity in a power system.

Keywords– FACTS,Power system, POD Controller,SVC(Static VAR compensator), SSSC(static synchronous series compensator),Voltage Stability.

[1] Molina, M.G. and P. E. Mercado, "Modeling of a Static Synchronous Compensator withSuperconducting Magnetic Energy Storage for Applications on Frequency Control", Proc. VIII SEPOPE, Brasilia, Brazil, 2002, pp. 17-22.

[2] Molina, M.G. and P. E. Mercado, "New Energy Storage Devices for Applications on Frequency Control of the Power System using FACTS Controllers," Proc. X ERLAC, Iguazú, Argentina, 14.6, 2003, 1-6.

[3] Molina, M.G. and P. E. Mercado, "Evaluation of Energy Storage Systems for application in the Frequency Control", Proc. 6th COBEP, Florianópolis, Brazil, 2001, pp. 479-484.

[4] M. Noroozian, L. Angquist, M. Ghandhari, G. Andersson,1997, "Use of UPFC for Optimal Power Flow Control," IEEE Transactions on Power Delivery, 12(4), pp. 1629-1634.

[5] M. Ghandhari, G. Andersson, I.A. Hiskens, 2001, "Control Lyapunov Functions for Series Devices," IEEE Transactions on Power Delivery, 16(4), pp. 689-694.

Abstract: Distributed power generation has got its importance with the day to day increase of power generation from renewable energy sources and from domestic customers with small generation units connected to the grid. Distributed power generation systems mostly use Power electronic converters for the interface with power grid. Here in this paper a single-phase inverter for DG systems requiring power quality features, such as harmonic and reactive power compensation for grid-connected operation are discussed. The idea is to integrate the DG unit functions with shunt active power filter capabilities. With this approach, the inverter controls the active power flow from the renewable energy source to the grid and also performs the nonlinear load current harmonic compensation by keeping the grid current almost sinusoidal. The control scheme employs a current reference generator based on sinusoidal signal integrator and instantaneous reactive power (IRP) theory together with a dedicated repetitive current controller. Simulation results obtained with PI and fuzzy controllers demonstrate the feasibility of the proposed solution.

Keywords - Distributed power generation, power conditioning, power quality and instantaneous reactive power.

[1] M. G. Villalva, J. R. Gazoli, and E. R. Filho, "Comprehensive approach to modeling and simulation of photovoltaic arrays," IEEE Trans. Power Electron., vol. 24, no. 5, pp. 1198–1208, May 2009.

[2] B. Yang, W. Li, Y. Zhao, and X. He, "Design and analysis of a gridconnected photovoltaic power system," IEEE Trans. Power Electron., vol. 25, no. 4, pp. 992–1000, Apr. 2010.

[3] Z. Chen, J. M. Guerrero, and F. Blaabjerg, "A review of the state of the art of power electronics for wind turbines," IEEE Trans. Power Electron., vol. 24, no. 8, pp. 1859–1875, Aug. 2009.

[4] T. E. McDermott and R. C. Dugan, "Distributed generation impact on reliability and power quality indices," in Proc. IEEE Rural Electr. Power Conf., 2002, pp. D3–D3_7.

[5] F. Blaabjerg, R. Teodorescu, M. Liserre, and A. V. Timbus, "Overview of control and grid synchronization for distributed power generation systems," IEEE Trans. Ind. Electron., vol. 53, no. 5, pp. 1398–1409, Oct. 2006.

[6] F. Blaabjerg, Z. Chen, and S. B. Kjaer, "Power electronics as efficient interface in dispersed power generation systems," IEEE Trans. Power Electron., vol. 19, no. 5, pp. 1184–1194, Sep. 2004.

[7] P. Rodriguez, A. V. Timbus, R. Teodorescu, M. Liserre, and F. Blaabjerg, "Flexible active power control of distributed power generation systems during grid faults," IEEE Trans. Ind. Electron., vol. 54, no. 5, pp. 2583– 2592, Oct. 2007.

[8] L. P. Kunjumuhammed and M. K. Mishra, "Comparison of single phase shunt active power filter algorithms," in Proc. IEEE Power India Conf., 2006, pp. 8–15.

[9] M. K. Ghartemani, H. Mokhtari, and M. R. Iravani, "A signal processing system for extraction of harmonics and reactive current of single phase systems," IEEE Trans. Power Electron., vol. 19, no. 3, pp. 979–986, Jul. 2004.

Abstract: AC motors in particular squirrel cage induction motor (SCIM) enjoy several inherent advantages like simplicity, reliability, robust, low cost and maintenance free. The operation of induction motors in the constant volts per hertz (V/f) mode has been known for many decades, and its principle is well understood. V/f control has displaced the dc motor to some extent, particularly in the lower kW range, and the majority of variable speed drives in operation today are of this type. However for high dynamic performance industrial applications their control remains a challenging problem because they exhibit coupled nature of the stator and rotor flux and also significant nonlinearities. Sliding mode control is novel and quite different than the conventional field oriented or direct torques control (DTC) and optimizes the torque response. A new stator and rotor flux observer based on continuous sliding mode which allows Induction motor operation at low speeds is proposed in this project. This model is characterized in the stator reference frame and modeled using MATLAB/SIMULINK.

Keywords: Induction Motor, sliding mode controller, sliding surface

[1] K.M.H. Kubota and T.Nakano, "DSP-based speed adaptive flux observer of induction Motor", IEEE Trans. Ind. Appl. vol.29, 1993 pp. 344-348.

[2] Hasan Zidan, Shuishi Fujji, Tsuyoshi Hanamoto, Reruo Tsujji "A simple Sensor-less vector Control System for Variable Speed Induction Motor Drives" paper conference.

[3] H. Tajima and Y. Hori. Speed sensorless field-orientation control of the induction Machine. IEEE Trans. Indust.Appl., 29(1):175–180, Jan/Feb 1993.

[4] Marcello montanaria , Sergei Peresadab , Andhrea Tillia , Alberto Toniellia "Speed Sensorless control of Induction Motor based on Indirect Field-Orientation".

[5] Karel Jezerink "Speed sensorless Torque control of induction Motor," University of Maribor, Faculty of Electrical Engineering and Computer Science.

[6] P.Vas, "Sensorless vector and direct torque control" Oxford University Press,1998.

[7] Vadim I. Utkin "Sliding Mode Cotrol Design Principles and Applications to Electric Drives", IEEE Trans on Industrial Electronics, VOL 40, NO.1. feb 1993 Tutorial Course, 1986.

[8] J.R.Zhang, S.J.Xu, and A.Rachid "Sliding Mode Controller for Automatic Path Tracking of Vehicles", Proceeding of the American Control Conference, Anchorage, AK May 8-10,2002.

Abstract: Independent power systems (IPS) consist of a solution for the electrification of applications when the access to a large transmission network is not reasonably viable or even unfeasible. Their size can range from few hundred Watts to tens or hundreds of MW.This paper discusses the economic analysis of integrating a solar, wind, battery storage systems into diesel-electric power systems for remote villages, in which the cost of electricity supplied is reduced with the help of different combinations of PV cells, wind with diesel, battery system. The economic part of the model calculates the fuel consumed, the kilo watt hours obtained per litre of fuel supplied, and the total cost of fuel, savings due to PV, wind and battery system. The above concept is studied for six different cases and their corresponding models are designed with the help of Matlab/Simulink Software

Keywords:- Independent power system, Renewable energy sources, PV cells ,wind power , Simulink

[1] Martin Kaltschmitt, Wolfgang Streicher, Andreas Wiese "Renewable Energy, Technology, Economics and Environment" published
by Springer-Verlag Berlin Heidelberg 2007
[2] Jun-hai SHI, Zhi-dan ZHONG, Xin-jian ZHU, Guang-yi CAO "Robust design and optimization for autonomous PV-wind hybrid
power systems" Journal of Zhejiang University SCIENCE ISSN 1673-565X (Print); ISSN 1862-1775 (Online) pp 401-409.
[3] O.C. Onar, M. Uzunoglu, and M.S. Alam, "Dynamic modelling, design and simulation of a wind/fuel cell/ultra-capacitor-based
hybrid power generation system," Journal of Power Sources- ScienceDirect, vol. 161, pp. 707-722, 28th March 2006.
[4] Ahmed Agus Setiawan, Yu Zhao, Rob Susanto-Lee, and Chem. V. Nayar, "Design, economic analysis and environmental
considerations of mini-grid hybrid power system with reverse Osmosis desalination plant for remote areas," Renewable Energy-
Elsevier, vol. 34, Iss.2, pp. 374-383, February 2009.

Abstract: Ac–ac power conversion, the most popular topologies are indirect ac–ac converters with a dc link matrix converters and direct pulse width modulation (PWM) ac–ac converters. The indirect ac–ac converters and matrix converters can provide variable output voltage and variable frequency. However, for applications, where only voltage regulation is needed, the direct PWM ac–ac converters are used to perform as ac choppers or power line conditioners with the following features: the provision of a better power factor and efficiency, low harmonic current in line, single-stage conversion, simple topology, ease of control, smaller size, and lower cost. The ac–ac conversions or ac–ac line conditioners can also perform conditioning, isolating, and altering of the incoming power in addition to voltage regulation. The direct PWM ac–ac converters can be derived from the dc–dc topologies, where all the unidirectional switches are substituted by bidirectional devices. This paper presents simulation of a Three-phase Three-leg Ac/Ac Converter simulation design using reduced number of power semiconductor devices, here nine IGBTs are used. This converter features sinusoidal inputs and outputs, unity power factor, and more importantly, low manufacturing cost. The experimental results from a 5kVA prototype system are provided.

Index Terms -AC/AC converter, reduced switch count topology, SVPWM

[1] B . Wu, High-power Converters and AC Drives. Piscatawa y, NJ:IEEE/Wiley, 2006.

[2] B . Singh, B. N. Singh, A. Chandra, K. Al-Haddad, A. Pandey, and D. P. Ko thari, "A review of three-phase improved p ower quality AC – DC converters," IEEE Trans. I nd. Electron., vol. 51, no. 3, pp. 641–660, Jun. 2004.

[3] F. B laabjerg, S. Frey sson, H. H. Hansen, and S. Hansen, "A new op-timized space-vector m odulation strategy for a component-minimized vo ltage source inverter," IEEE Trans. Power Electron., vol. 12, no. 4, pp. 704–714, Jul. 1997.

[4] R . L. A. R ibeiro, C. B. Jacobina, E. R . C . d a Silva, and A. M. N. Lima, "AC/AC converter with four switch three phase structures," in Proc. I EEE PESC , 1996, vol. 1, pp. 134–139.

[5] K. Gi-Taek and T. A. Lipo, "VSI-PWM rectifier/inverter system with a reduced switch count," IEEE Trans. Ind. Appl., vol. 32, no. 6, pp. 1331– 1337, Nov./Dec. 1996.

[6] A. B ouscayrol, B. Francois, P. Delarue, and J. Niiranen, "Control imple- mentation o f a five-leg AC–AC converter to supply a three-phase induction machine," IEEE Trans. Power Electron., vol. 20, no. 1, pp. 107–115, Jan. 2005.

[7] C. B. Jacobina, I. S. de Freitas, E. R. C. da Silva, A. M. N. Lima, and R. L. A. Ribeiro, "Reduced switch count DC-link AC–AC five-leg converter,"IEEE Trans. Power Electron., vol. 21, no. 5, pp. 1301–1310, Sep. 2006. [8] C. B. Jacobina, I. S. de Freitas, and A. M. N. Lima, "DC-link three-phaseto- three-phase four-leg converters," IEEE Trans. Ind. Electron., vol. 54, no. 4, pp. 1953–1961, Aug. 2007.

[9] J. Minibock and J. W. Kolar, "Novel concept for mains voltage proportional input current shaping of a VIENNA rectifier eliminating controller multipliers," IEEE Trans. Ind. Electron., vol. 52, no. 1, pp. 162–170, Feb. 2005.

[10] T. Nussbaumer, M. Baumann, and J.W. Kolar, "Comprehensive design of a three-phase three-switch buck-type PWM rectifier," IEEE Trans. Power Electron., vol. 22, no. 2, pp. 551–562, Mar. 2007.

Abstract: A new converter transformer and an inductive filtering method are presented to solve the existing problems of the traditional converter transformer and the passive filtering method of the high-voltage direct current (HVDC) system. It adopts the ampere-turn balance of the transformer as the filtering mechanism. A tap at the linking point of the prolonged winding and the common winding of the secondary windings is connected with the LC resonance circuit. It can realize the goal that once the harmonic current flows into the prolonged winding, the common winding will induct the opposite harmonic current to balance it by the zero impedance design of the common winding and the proper configuration of LC parameters, so there will be no inductive harmonic current in the primary winding. Moreover, the reactive power that the converter needs can be partly compensated in the secondary winding. Simulation results have verified the correctness of the theoretical analysis. The new converter transformer can greatly reduce the harmonic content in the primary winding, loss, and noise generated by harmonics in the transformer, and the difficulty of the transformer's insulation design. Index Terms: Filtering mechanism, harmonic, high-voltage direct current (HVDC), inductive filtering, new converter transformer

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[5]. J. Alan and C. Forrest, ―Harmonic load losses in HVDC converter transformers,‖ IEEE Trans. Power Del., vol. 6, no. 1, pp. 153–157, Jan. 1991.
[6]. M. J. Heathcote, The J&P Transformer Book, 25 ed. Oxford, U.K.: Reed, 1998.
[7]. K. Eckholz and P. Heinzig, ―HVDC-transformer-a technical challenge,‖ in Proc. IEEE Int. Conf. Power Syst. Technol., Oct. 13–17, 2002, vol. 1, pp. 547–551.
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