access icon free Circulating current suppression with improved DC-link power quality for modular multilevel converter

Despite having more advantages, a modular multilevel converter (MMC) has a circulating current as one of its main drawbacks that augments arm current greatly. However, circulating current suppression (CCS) of the conventional MMC will deteriorate the power quality of direct current (DC)-link voltage. This study proposes the CCS by applying the three-winding transformer and a DC–alternating current CCS inverter. The mathematical models of the proposed MMC and circulating current are analysed in detail. The parameter setting of the three-winding transformer is also discussed and is set to have an equivalent arm inductance of the conventional MMC to make comparisons. The comparing results validate that the proposed MMC can exhibit much better performance under steady and dynamic conditions. The significant DC-link voltage ripple that exists in the conventional MMC does not appear. The mean-square-error values of DC-link voltage have more than 90 per cent improvement under steady and dynamic conditions. Due to this contribution, the proposed MMC can provide better DC-link power quality.

Inspec keywords: power transformers; power supply quality; invertors; transformer windings; HVDC power transmission; mean square error methods

Other keywords: steady conditions; modular multilevel converter; dynamic conditions; circulating current suppression; mean-square-error values; three-winding transformer; high-voltage-direct-current transmission; MMC; direct current link voltage; equivalent arm inductance; parameter setting; improved DC-link power quality; DC-alternating current CCS inverter

Subjects: d.c. transmission; Power supply quality and harmonics; Interpolation and function approximation (numerical analysis); DC-AC power convertors (invertors); Transformers and reactors

References

    1. 1)
      • 13. Pou, J., Ceballos, S., Konstantinou, G., et al: ‘Circulating current injection methods based on instantaneous information for the modular multilevel converter’, IEEE Trans. Ind. Electron., 2015, 62, (2), pp. 777788.
    2. 2)
      • 9. Qingrui, T., Zheng, X., Lie, X.: ‘Reduced switching-frequency modulation and circulating current suppression for modular multilevel converters’, IEEE Trans. Power Deliv., 2011, 26, (3), pp. 20092017.
    3. 3)
      • 2. Fehr, H., Gensior, A., Müller, M.: ‘Analysis and trajectory tracking control of a modular multilevel converter’, IEEE Trans. Power Electron., 2015, 30, (1), pp. 398407.
    4. 4)
      • 7. Debnath, S., Qin, J., Bahrani, B., et al: ‘Operation, control, and applications of the modular multilevel converter: a review’, IEEE Trans. Power Electron., 2015, 30, (1), pp. 3753.
    5. 5)
      • 12. Zhang, M., Huang, L., Yao, W., et al: ‘Circulating harmonic current elimination of a CPS-PWM-based modular multilevel converter with a plug-in repetitive controller’, IEEE Trans. Power Electron., 2014, 29, (4), pp. 20832097.
    6. 6)
      • 20. Kay, S.M.: ‘Fundamentals of statistical signal processing’ (Prentice Hall PTR, 1993), pp. 1920.
    7. 7)
      • 8. Saad, H., Dennetière, S., Mahseredjian, J., et al: ‘Modular multilevel converter models for electromagnetic transients’, IEEE Trans. Power Deliv., 2014, 29, (3), pp. 14811489.
    8. 8)
      • 1. Ilves, K., Harnefors, L., Norrga, S., et al: ‘Predictive sorting algorithm for modular multilevel converters minimizing the spread in the submodule capacitor voltages’, IEEE Trans. Power Electron., 2015, 30, (1), pp. 440449.
    9. 9)
      • 6. Luo, L., Zhang, Y., Jia, L., et al: ‘A novel method based on self-power supply control for balancing capacitor static voltage in mmc’, IEEE Trans. Power Electron., 2017, PP, (99), pp. 11.
    10. 10)
      • 19. Casanellas, F.: ‘Losses in PWM inverters using IGBTS’, IEE Proc. – Electr. Power Appl., 1994, 141, (5), pp. 235239.
    11. 11)
      • 15. Xu, S., Huang, A., Xijun, N., et al: ‘AC circulating currents suppression in modular multilevel converter’. IECON 2012–38th Annual Conf. on IEEE Industrial Electronics Society, Montreal, Quebec, Canada, 25–28 October, 2012, pp. 191196.
    12. 12)
      • 18. Briz, F., Degner, M.W., Lorenz, R.D.: ‘Analysis and design of current regulators using complex vectors’, IEEE Trans. Ind. Appl., 2000, 36, (3), pp. 817825.
    13. 13)
      • 3. Vidal-Albalate, R., Beltran, H., Rolan, A., et al: ‘Analysis of the performance of MMC under fault conditions in HVDC-based offshore wind farms’, IEEE Trans. Power Deliv., 2016, 31, (2), pp. 839847.
    14. 14)
      • 16. Yang, H., Saeedifard, M.: ‘A capacitor voltage balancing strategy with minimized ac circulating current for the DC–DC modular multilevel converter’, IEEE Trans. Ind. Electron., 2017, 64, (2), pp. 956965.
    15. 15)
      • 5. Lesnicar, A., Marquardt, R.: ‘An innovative modular multilevel converter topology suitable for a wide power range’. 2003 IEEE Bologna Power Tech Conf., Bologna, Italy, 23–26 June, 2003.
    16. 16)
      • 10. Rohner, S., Bernet, S., Hiller, M., et al: ‘Analysis and simulation of a 6 kv, 6 mva modular multilevel converter’. 2009 35th Annual Conf. of IEEE Industrial Electronics, Porto, 3–5 November, 2009, pp. 225230.
    17. 17)
      • 4. Jiangchao, Q., Saeedifard, M.: ‘Predictive control of a modular multilevel converter for a back-to-back HVDC system’, IEEE Trans. Power Deliv., 2012, 27, (3), pp. 15381547.
    18. 18)
      • 11. Qiang, S., Wenhua, L., Xiaoqian, L., et al: ‘A steady-state analysis method for a modular multilevel converter’, IEEE Trans. Power Electron., 2013, 28, (8), pp. 37023713.
    19. 19)
      • 14. Ilves, K., Antonopoulos, A., Norrga, S., et al: ‘Steady-state analysis of interaction between harmonic components of arm and line quantities of modular multilevel converters’, IEEE Trans. Power Electron., 2012, 27, (1), pp. 5768.
    20. 20)
      • 17. Wang, J., Liang, J., Wang, C., et al: ‘Circulating current suppression for MMC-HVDC under unbalanced grid conditions’, IEEE Trans. Ind. Appl., 2017, PP, (99), pp. 11.
http://iet.metastore.ingenta.com/content/journals/10.1049/iet-gtd.2017.1109
Loading

Related content

content/journals/10.1049/iet-gtd.2017.1109
pub_keyword,iet_inspecKeyword,pub_concept
6
6
Loading