Analytical modeling of MMCs with asymmetric cell voltages for utility-scale renewable energy integration

Abhijit Kshirsagar; Anushree Ramanath; Jeyaram Durga Manian Deivanayagam; Sreekanth Thamballa; Ned Mohan

doi:10.1109/COMPEL.2019.8769629

Analytical modeling of MMCs with asymmetric cell voltages for utility-scale renewable energy integration

Abhijit Kshirsagar, Anushree Ramanath, Jeyaram Durga Manian Deivanayagam, Sreekanth Thamballa, Ned Mohan

Electrical and Computer Engineering

Research output: Chapter in Book/Report/Conference proceeding › Conference contribution

Abstract

Modular Multilevel Converters (MMCs) have been popular in high voltage power conversion applications because they use a number of modules with relatively low voltage ratings to be cascaded to achieve high voltage operation. In HVDC transmission, for instance, a large number of modules are required to reach the desired operating voltage. Recent research has focused on using MMCs in medium voltage applications to interface renewable energy sources to the distribution grid at voltage levels of up to 35kV. Asymmetric voltages have been used with great success in conventional multilevel inverter topologies to lower the total device count, thereby resulting in a lower total system cost and complexity. MMCs with asymmetric voltages in a 2:1 ratio have been proposed but require complex voltage balancing schemes. Asymmetric multilevel inverters with other voltage ratios (such as 3:1) have been shown to have potentially lower device counts than topologies with 2:1 ratios. However, conventional modulation schemes do not scale to MMCs with 3:1 voltage ratios. This paper presents a generalized analytical model and control scheme for asymmetric MMCs using space-vectors. Capacitor voltages are balanced by a combination of common-mode and differential-mode offsets in the modulating signal. A scalable, level-shifted carrier based modulation scheme is used which eliminates recursive timing calculations. The proposed scheme is modeled in MATLAB/Simulink and the simulation results are presented.

Original language	English (US)
Title of host publication	2019 IEEE 20th Workshop on Control and Modeling for Power Electronics, COMPEL 2019
Publisher	Institute of Electrical and Electronics Engineers Inc.
ISBN (Electronic)	9781728118420
DOIs	https://doi.org/10.1109/COMPEL.2019.8769629
State	Published - Jun 2019
Event	20th IEEE Workshop on Control and Modeling for Power Electronics, COMPEL 2019 - Toronto, Canada Duration: Jun 17 2019 → Jun 20 2019

Publication series

Name	2019 IEEE 20th Workshop on Control and Modeling for Power Electronics, COMPEL 2019

Conference

Conference	20th IEEE Workshop on Control and Modeling for Power Electronics, COMPEL 2019
Country/Territory	Canada
City	Toronto
Period	6/17/19 → 6/20/19

Bibliographical note

Funding Information:
*This work was supported by the RDF Grant from Xcel Energy and IonE, University of Minnesota.

Publisher Copyright:
© 2019 IEEE.

Keywords

Modular Multilevel Converters (MMCs)
asymmetric cell voltage
renewable energy integration
space vector analysis

UN SDGs

This output contributes to the following UN Sustainable Development Goals (SDGs)

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10.1109/COMPEL.2019.8769629

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Kshirsagar, A., Ramanath, A., Deivanayagam, J. D. M., Thamballa, S., & Mohan, N. (2019). Analytical modeling of MMCs with asymmetric cell voltages for utility-scale renewable energy integration. In 2019 IEEE 20th Workshop on Control and Modeling for Power Electronics, COMPEL 2019 Article 8769629 (2019 IEEE 20th Workshop on Control and Modeling for Power Electronics, COMPEL 2019). Institute of Electrical and Electronics Engineers Inc.. https://doi.org/10.1109/COMPEL.2019.8769629

Analytical modeling of MMCs with asymmetric cell voltages for utility-scale renewable energy integration. / Kshirsagar, Abhijit; Ramanath, Anushree; Deivanayagam, Jeyaram Durga Manian et al.
2019 IEEE 20th Workshop on Control and Modeling for Power Electronics, COMPEL 2019. Institute of Electrical and Electronics Engineers Inc., 2019. 8769629 (2019 IEEE 20th Workshop on Control and Modeling for Power Electronics, COMPEL 2019).

Research output: Chapter in Book/Report/Conference proceeding › Conference contribution

Kshirsagar, A, Ramanath, A, Deivanayagam, JDM, Thamballa, S & Mohan, N 2019, Analytical modeling of MMCs with asymmetric cell voltages for utility-scale renewable energy integration. in 2019 IEEE 20th Workshop on Control and Modeling for Power Electronics, COMPEL 2019., 8769629, 2019 IEEE 20th Workshop on Control and Modeling for Power Electronics, COMPEL 2019, Institute of Electrical and Electronics Engineers Inc., 20th IEEE Workshop on Control and Modeling for Power Electronics, COMPEL 2019, Toronto, Canada, 6/17/19. https://doi.org/10.1109/COMPEL.2019.8769629

Kshirsagar A, Ramanath A, Deivanayagam JDM, Thamballa S, Mohan N. Analytical modeling of MMCs with asymmetric cell voltages for utility-scale renewable energy integration. In 2019 IEEE 20th Workshop on Control and Modeling for Power Electronics, COMPEL 2019. Institute of Electrical and Electronics Engineers Inc. 2019. 8769629. (2019 IEEE 20th Workshop on Control and Modeling for Power Electronics, COMPEL 2019). doi: 10.1109/COMPEL.2019.8769629

Kshirsagar, Abhijit ; Ramanath, Anushree ; Deivanayagam, Jeyaram Durga Manian et al. / Analytical modeling of MMCs with asymmetric cell voltages for utility-scale renewable energy integration. 2019 IEEE 20th Workshop on Control and Modeling for Power Electronics, COMPEL 2019. Institute of Electrical and Electronics Engineers Inc., 2019. (2019 IEEE 20th Workshop on Control and Modeling for Power Electronics, COMPEL 2019).

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Analytical modeling of MMCs with asymmetric cell voltages for utility-scale renewable energy integration

Abstract

Publication series

Conference

Bibliographical note

Keywords

UN SDGs

Access

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