An enhanced dq-based vector control system for modular multilevel converters feeding variable speed drives

Espinoza, Mauricio; Cardenas, Roberto; Diaz, Matias; Clare, Jon C.

Abstract

Modular multilevel converters (M2C) are considered an attractive solution for high power drive applications. However, energy balancing within the converter is complex to achieve, particularly when the machine is operating at low rotational speeds. In this paper, a new control system, based on cascaded control loops and a vector-power-voltage (vPV) model of the M2C, is proposed. The control system is implemented in a dq-synchronous frame rotating at ωe rad/s with the external loop regulating the capacitor voltages using proportional-integral (PI) controllers. The internal loop controls the converter currents using PI and resonant controllers. In addition, the control systems required to operate the machine at other points, i.e., at medium and high rotational speeds, are also discussed in this paper. Experimental results obtained with an M2C-based drive laboratory prototype with 18 power cells are presented in this paper.

Citation

Espinoza, M., Cardenas, R., Diaz, M., & Clare, J. C. (2017). An enhanced dq-based vector control system for modular multilevel converters feeding variable speed drives. IEEE Transactions on Industrial Electronics, 64(4), 2620-2630. https://doi.org/10.1109/TIE.2016.2637894

• Journal Article Type: Article
• Acceptance Date: Oct 16, 2016
• Online Publication Date: Dec 12, 2016
• Publication Date: Apr 30, 2017
• Deposit Date: Jul 4, 2017
• Publicly Available Date: Jul 4, 2017
• Journal: IEEE Transactions on Industrial Electronics
• Print ISSN: 0278-0046
• Electronic ISSN: 1557-9948
• Publisher: Institute of Electrical and Electronics Engineers
• Peer Reviewed: Peer Reviewed
• Volume: 64
• Issue: 4
• Pages: 2620-2630
• DOI: https://doi.org/10.1109/TIE.2016.2637894
• Keywords: Modular multilevel converter, Variable speed drives, Low-frequency operation, Voltage balancing
• Public URL: https://nottingham-repository.worktribe.com/output/858026
• Publisher URL: http://ieeexplore.ieee.org/document/7781663/
• Additional Information: c2016 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other users, including reprinting/ republishing this material for advertising or promotional purposes, creating new collective works for resale or redistribution to servers or lists, or reuse of any copyrighted components of this work in other works
• Contract Date: Jul 4, 2017