Technical Report: Optimal Current Trajectories for Power Converters with Minimal Common Mode Voltage

This article addresses the topic of computing optimized pulse patterns with common mode voltage constraints. The main thrust is to obtain tractable reformulations of the CMV constraints in the frequency domain in order to avoid complex mixed time-frequency formulations. The resulting optimization problem is a nonlinear one for which efficient numerical solvers are readily available. Moreover, we provide an algorithmic way of reducing the conservatism in the reformulated problem and validate our method with numerical illustrations that highlight the benefit of the proposed approach

Generalized optimal pulsewidth modulation of multilevel inverters for low-switching-frequency control of medium-voltage high-power industrial AC drives

10.1109/TIE.2012.2217717IEEE Transactions on Industrial Electronics60104215-4224ITIE

Optimization of the efficiency in an induction machine drive by algorithm based on the interior point method

[EN] This work optimizes the efficiency of the squirrel cage type Inverter-Induction Machine (IM) system, using an algorithm based on the Interior Point Method (IPM), where the input variables are the electromagnetic torque and the rotor speed at steady state,and as outputs the optimal efficiency and slip values are obtained. The optimum rotor flux value is calculated, which is used as a reference in the flux control loop, in the direct control vector method of the IM. Simulation results are obtained where the increase in efficiency is observed in low load states. The experimental installation used in the implementation of the vector control with maximum system efficiency is described, and the experimental results obtained are shown. A discussion is carried out on the results and the use of the Interior Point Optimization Method.[ES] En este trabajo se realiza la optimización de la eficiencia del sistema  Inversor-Máquina de Inducción (MI) del tipo jaula de ardilla, utilizando un algoritmo basado en el Método de Punto Interior (MPI), donde las variables de entrada son el par electromagnético y la velocidad del rotor en estado estacionario, y como salidas se obtienen los valores de la eficiencia óptima y del deslizamiento. Se calcula el valor del flujo óptimo del rotor que se utiliza como referencia en el lazo de control del flujo, en el control vectorial método directo de la MI. Se obtienen resultados de simulación donde se observa el incremento de la eficiencia en estados de baja carga. Se describe la instalación experimental usada en la implementación del control vectorial con máxima eficiencia del sistema, y se muestran los resultados experimentales obtenidos. Se realiza una discusión sobre los resultados y la utilización del Método de Optimización de Punto Interior.Instituto Politécnico Nacional (IPN), proyecto multidisciplinario registro número 1995.Pacheco-Montiel, J.; Badaoui, M.; Rodríguez-Rivas, J.; Alvarado-Farías, JM.; Carranza-Castillo, O.; Ortega-González, R. (2021). Optimización de la eficiencia en el accionamiento de una máquina de inducción mediante algoritmo basado en el método de punto interior. Revista Iberoamericana de Automática e Informática industrial. 18(4):336-346. https://doi.org/10.4995/riai.2020.13418OJS336346184Andréasson, N., Evgrafov, A., Patriksson, M, 2020. An Introduction to Continuous Optimization Fundations & Fundamental Algorithms. Dover Publications.Benson, H. Y., Shanno, D. F, 2014. Interior-point methods for nonconvex nonlinear programming: cubic regularization. Comput Optim Appl, 58:323-346. https://doi.org/10.1007/s10589-013-9626-8Borisevich, A., and Schullerus, G, 2016. Energy Efficient Control of an Induction Machine Under Torque Step Changes. IEEE Trans. on Energy Conv., vol. 31, no. 4, pp. 1295-1303, December. https://doi.org/10.1109/TEC.2016.2561307Capitanescu, F., Wehenkel, L., 2013. Experiments with the interior-point method for solving large scale optimal power flow problems. Electric Power Systems Research, vol. 95, pp. 276-283. https://doi.org/10.1016/j.epsr.2012.10.001Casacio, L., Lyra, C., Oliveira, A.R.L, 2019. Interior point methods for power flow optimization with security constraints. Intl. Trans. in Op. Res. 26 (2019) 364-378. https://doi.org/10.1111/itor.12279Colín, E. A. O., González, I. H. G., Rivas, J. J. R., Castillo, O. C., González, R. O., Caporal, R. M., 2017. Implementación del Algoritmo Sünter-Clare en un Convertidor Matricial 3x3. Revista Iberoamericana de Automática e Informática Industrial (RIAI), vol. 14, no. 4, pp. 446-454, Oct.-Dic. https://doi.org/10.1016/j.riai.2017.06.002De Almeida, A. T., Ferreira, F. J. T. E., Duarte, A. Q, 2014. Technical and Economical Considerations on Super High-Efficiency Three-Phase Motors. IEEE Trans. on Ind. App., vol. 50, no. 2, pp. 1274-1285, March/April. https://doi.org/10.1109/TIA.2013.2272548Eftekhari, S. R., Davari, S. A., Naderi, P., García C., Rodriguez, J, 2020. Robust Loss Minimization for Predictive Direct Torque and Flux Control of an Induction Motor With Electrical Circuit Model. IEEE Trans. on Power Electronics, vol. 35, no. 5, pp. 5417-5426, May. https://doi.org/10.1109/TPEL.2019.2944190Farhat, I. A., El-Hawary, M. E, 2009. Interior point methods application in optimum operational scheduling of electric power systems. IET Generation, Transmission & Distribution, vol. 3, Iss. 11, pp. 1020-1029. https://doi.org/10.1049/iet-gtd.2008.0573IEA International Energy Agency. World Energy Outlook, 2018. IEA, Paris 2018. 01/2020. https://www.iea.org/reports/world-energy-outlook-2018.IEC 60034-30-1, 2014. Efficiency classes of line operated AC motors (IE-code), Edition 1.0.Mallik, S., Mallik, K., Barman, A., Maiti, D., Biswas, S. K., Deb, N. K., Basu, S, 2017. Efficiency and Cost Optimized Design of an Induction Motor Using Generic Algorithm. IEEE Trans. on Ind. Appl., vol. 64, no. 12, pp. 9854-9863, December. https://doi.org/10.1109/TIE.2017.2703687McElveen, R., Melfi, M., McFarland, J, 2019. Improved Characterization of Polyphase Induction Motor Losses: Test Standards Must Be Modified to Improve Efficiency Optimization. IEEE Ind. Appl. Magazine., pp. 61-68, Nov./Dec. https://doi.org/10.1109/MIAS.2018.2875208Rao, N., and Chamund, D, 2014. Calculating Power Losses in an IGBT Module. Application Note. DYNEX Power Control through Innovation.Rathore, A. K., Holtz, J., Boller, T, 2013. Generalized Optimal Pulsewidth Modulation of Multilevel Inverters for Low-Switching-Frequency Control of Medium-Voltage High-Power Industrial AC Drives. IEEE Trans. on Ind. Electronics, vol. 60, no. 10, pp. 4215-4224, Oct. https://doi.org/10.1109/TIE.2012.2217717Seung-Ki, S, 2011. Control of Electric Machine Drive Systems. IEEE Press & Wiley. Printed in the USA.Salomon, C. P., Sant'Ana, W. C., Borges da Silva, L. E., Torres, G. L., Bonaldi, E. L., Olveira, L. E. L., Borges da Silva, J. G, 2015. Induction Motor Efficiency Evaluation Using a New Concept of Stator Resistance. IEEE Trans. on Inst. and Meas., vol. 64, no. 11, pp. 2908-2917, November. https://doi.org/10.1109/TIM.2015.2437632Santos, V. S., Felipe, P. R. V, Sarduy, J. R. G., Lemozy, N. A. L., Jurado, A., Quispe, E. C, 2015. Procedure for Determining Induction Motor Efficiency Working Under Distorted Grid Voltages. IEEE Trans. on Energy Conv., vol. 30, no. 1, pp. 331-339, March. https://doi.org/10.1109/TEC.2014.2335994Shukla, S., and Singh, B, 2017. Solar Powered Sensorless Induction Motor Drive with Improved Efficiency forWater Pumping. IET Power Electronics, vol. 11, issue 3, pp. 1-11, March. https://doi.org/10.1049/iet-pel.2017.0452Stumper, J. F., Dötlinger, A., Kennel, R, 2013. Loss Minimization of Induction Machines in Dynamic Operation. IEEE Trans. on Energy Conv., vol. 28, no. 3, pp. 726-735, September. https://doi.org/10.1109/TEC.2013.2262048Sul, S. K., 2011. Control of Electric Machine Drive Systems. IEEE Press-Wiley & Sons. https://doi.org/10.1002/9780470876541Taheri, A., Rahmati, A., Kaboli, S, 2012. Efficiency Improvement in DTC of Six-Phase Induction Machine by Adaptive Gradient Descent of Flux. IEEE Trans. on Power Electronics, vol. 27, no. 3, pp. 1552-1562, March. https://doi.org/10.1109/TPEL.2011.2163420Vanderbei, R. J., Shanno, D. F, 1999. Interior-point methods for nonconvex nonlinear programming. Computational Optimization and Applications, 13, 31-252. https://doi.org/10.1023/A:1008677427361Vural, A. M, 2015. Interior point-based slack-bus free-power flow solution for balanced islanded microgrids. Int. Trans. Electr. Energ. Syst, 26:968-992. https://doi.org/10.1002/etep.2117Xu, W., Hu, D., Lei, G., Zhu, J, 2019. System-Level Efficiency Optimization of a Linear Induction Motor Drive System. IEEE Trans. on Electrical Machines and Systems, vol. 3, no. 3, pp. 285-291, Sept. https://doi.org/10.30941/CESTEMS.2019.00037Xu, W., Xiao, X., Du, G., Zou, J, 2020. Comprehensive Efficiency Optimization of Linear Induction Motors for Urban Transit. IEEE Trans. on Vehicular Tech., vol. 69, no. 1, pp. 131-139, January. https://doi.org/10.1109/TVT.2019.295395

Técnicas de modulação síncrona otimizada para a melhoria de desempenho de conversores multiníveis no acionamento de máquinas elétricas

Tese (doutorado) - Universidade Federal de Santa Catarina, Centro Tecnológico. Programa de Pós-Graduação em Engenharia Elétrica, Florianópolis, 2015Com o crescente interesse da indústria em inversores multiníveis de alta potência para aplicações em média tensão e com as limitações tecnológicas em dispositivos semicondutores de potência de alta tensão, a técnica de modulação síncrona otimizada, desenvolvida originalmente para conversores de dois e três níveis, tornou-se novamente um tópico de interesse da Eletrônica de Potência, agora para a melhoria de formas de onda de tensão multiníveis. Esta tese propõe uma nova formulação para o problema de otimizar a modulação de conversores multiníveis com diferentes objetivos, incluindo em um único problema de otimização a decisão da direção de cada comutação bem como os ângulos em que estas devem ocorrer e, assim, definindo completamente as formas de onda de tensão otimizadas. Esta técnica é aqui empregada em aplicações selecionadas, as quais demonstram os ganhos em desempenho obtidos frente à técnicas convencionais de modulação de inversores multiníveis. Resultados extensivos de experimentação de um inversor 5-níveis acionando um motor síncrono de ímãs permanentes são apresentados e comprovam os achados teóricos. Abstract : With the growing interest of the industry in high power medium voltage multilevel inverters and the technological limitation in high voltage power semiconductors devices, the synchronous optimal pulsewidth modulation technique, originally developed for two/three level inverters, became once again a topic of righ interest to Power Electronics community, now to optimize multilevel waveforms. This work proposes a new formulation for the problem of optimizing the modulation pattern of multilevel converters, including in a single optimization problem the decision of the directions for each step transition in addition to the switching angles and, thus, completely defining the optimized multilevel waveform for a given modulation index. This is done for a single and also multiple objectives problems. This technique is applied here in selected applications, which shows the gains achieved with respect to the conventional modulation techniques for multilevel inverters. Results from extensive experimentation with a 5-levels inverter driving a permanent magnet motor are presented and confirm the theoretical findings