Controlling of Multi-Level Inverter under Shading Conditions Using Artificial Neural Network

Authors: Abed Sami Qawasme, Sameer Khader

Abstract:

This paper describes the effects of photovoltaic voltage changes on Multi-level inverter (MLI) due to solar irradiation variations, and methods to overcome these changes. The irradiation variation affects the generated voltage, which in turn varies the switching angles required to turn-on the inverter power switches in order to obtain minimum harmonic content in the output voltage profile. Genetic Algorithm (GA) is used to solve harmonics elimination equations of eleven level inverters with equal and non-equal dc sources. After that artificial neural network (ANN) algorithm is proposed to generate appropriate set of switching angles for MLI at any level of input dc sources voltage causing minimization of the total harmonic distortion (THD) to an acceptable limit. MATLAB/Simulink platform is used as a simulation tool and Fast Fourier Transform (FFT) analyses are carried out for output voltage profile to verify the reliability and accuracy of the applied technique for controlling the MLI harmonic distortion. According to the simulation results, the obtained THD for equal dc source is 9.38%, while for variable or unequal dc sources it varies between 10.26% and 12.93% as the input dc voltage varies between 4.47V nd 11.43V respectively. The proposed ANN algorithm provides satisfied simulation results that match with results obtained by alternative algorithms.

Keywords: Multi level inverter, genetic algorithm, artificial neural network, total harmonic distortion.

References:

[1] Gilbert M. Masters, Renewable and Efficient Energy Systems, 1st edition, 2003, ch.9.
[2] S. Koura, M. Malinowski, K. Gopakumar, J. Pou, L. G. Franquelo, B. Wu, J. Rodriguez, M. Perez, J. I. Leon, "Recent Advances and Industrial Applications of Multilevel Converters, IEEE Transactions on Industrial Electronics", vol. 57, no. 8, pp. 2553-2580, Aug. 2010.
[3] R. Rangarajan, F. E. Villaseca, “A switching scheme for multilevel converters with non-equal DC sources”, 39th North American Power Symposium, pp. 308-313, Sept.2007.
[4] B. Ozpineci, L. M. Tolbert, J. N. Chiasson, “Harmonic optimization of multilevel converters using genetic algorithms,” IEEE Power Electronics Letters, vol. 3, no. 3,pp. 92-95, Sept. 2005.
[5] J. N. Chiasson, L. M. Tolbert, K. J. McKenzie, Z. Du, “A unified approach to solving the harmonic elimination equations in multilevel converters,” IEEE Transactions on Power Electronics, vol. 19, no. 2, pp. 478-490, March. 2004.
[6] J. N. Chiasson, L. M. Tolbert, K. J. McKenzie, Z. Du, “Elimination of harmonics in a multilevel converter using the theory of symmetric polynomials and resultants,” IEEE Transactions on Control Systems Technology, vol. 13, no. 2, pp. 216-223, March 2005.
[7] Z. Du, L. M. Tolbert, J. N. Chiasson, H. Li, “Low switching frequency active harmonic elimination in multilevel converters with unequal DC voltages,” Annual Meeting of the IEEE Industry Applications Society, pp. 92-98.
[8] Z. Du, L. M. Tolbert, J. N. Chiasson, “Active harmonic elimination for multilevel converters,” IEEE Transactions on Power Electronics, vol. 21, no. 2, pp. 459-469, March 2006.
[9] D. Ahmadi, Jin Wang, “Selective harmonic elimination for multilevel inverters with unbalanced DC inputs,” IEEE Vehicle Power and Propulsion Conference, pp.773-778, Sept. 2009.
[10] M. S. A. Dahidah, V. G. Agelidis, “Selective harmonic elimination multilevel converter control with variant DC sources,” IEEE Conference on Industrial Electronics and Applications, pp. 3351-3356, May 2009.
[11] J. Rodriguez, J. Lai, F. Z. Peng, “Multilevel inverters: a survey of topologies, control and applications,” IEEE Transactions on Industrial Electronics, vol. 49, no. 4, pp.724-738, Aug. 2002.
[12] M. S. A. Dahidah, V. G. Adelids, “Selective harmonic elimination PWM control for cascaded multilevel voltage source converters: A generalized formula,” IEEE Transactions on Power Electronics, vol. 23, no. 4, pp. 1620-1630, July 2008.
[13] F. J. T. Filho, L. M. Tolbert, Y. Cao, B. Ozpineci, "Real time selective harmonic minimization for multilevel inverters connected to solar panels using artificial neural network angle generation", IEEE Energy Conversion Congress and Exposition, pp. 594-598, Sept. 2010.
[14] M. Srinivas, L. M. Patnaik, “Genetic algorithms: a survey,” IEEE Computer Society Press., vol. 27, no. 6, pp. 17-26, Jun 1994.
[15] D. E. Goldberg, Genetic Algorithms in Search, Optimization, and Machine Learning. MA: Addison-Wesley, 1989.
[16] K.F. Man, K.S. Tang, S. Kwang, “Genetic algorithms: concepts and applications
[in engineering design],” IEEE Transactions on Industrial Electronics, vol.43, no.5, pp.519-534, Oct 1996.
[17] C. R. Houck, J. A. Joins and M. G. Kay, “A genetic algorithm for function optimization: A MATLAB implementation,” Technical Report NCSU-IE-TR-95-09, North Carolina State University, Raleigh, NC (1995).
[18] J. J. Hopfield, “Artificial neural networks,” IEEE Circuits and Devices Magazine, vol. 4, no. 5, pp. 3-10, Sep.1988.129
[19] R. Aggarwal, Y. Song, “Artificial neural networks in power systems II: types of artificial neural networks,” Power Engineering Journal, vol. 12, no. 1, pp. 41-47, Feb. 1998.
[20] R. Aggarwal, Y. Song, “Artificial neural networks in power systems I: general introduction to neural computing,” Power Engineering Journal, vo. 11, no. 3, pp. 129-134, Jun. 1997.
[21] M .J. Willis, C. Di Massimo, G. A. Montague, M. T. Them, A. J. Morris, “Artificial neural networks in process engineering,” IEE Proceedings in Control Theory and Applications, vol. 138, no. 3, pp. 256-266, May 1991.
[22] A.K. Jain, Jincheng Mao, K. M. Mohiuddin, “Artificial neural networks: a tutorial,” Computer, vol. 29, no. 3, pp. 31-44, Mar 1996.
[23] MATLAB /Simulink User's Guide , 2016, www.mathwork.com