New power equalization modulation strategy for CHB seven‑level inverters

Jun Gu; Run-Zhe Cai; Xiang-Yu Zhou; Chao Ding; Wei-Jian Wang

New power equalization modulation strategy for CHB seven‑level inverters

Vol. 23, No. 7, pp. 1063-1072, Jul. 2023

10.1007/s43236-023-00606-2

Switching states

Equalization time

Harmonic elimination characteristics

Optimized modulation strategy

Abstract

For cascaded H-bridge (CHB) multilevel converters, the traditional in-phase disposition (IPD) modulation strategy has excellent harmonic elimination characteristics, but it leads to a single state of the switching tubes and unbalanced output power of each unit. In this paper, a new power equalization modulation strategy and its optimization are proposed, which solves the problem of power equalization, while taking into account the harmonic elimination performance of the output voltage and power equalization time. The new power equalization modulation strategy makes the carrier rotate in different carrier layers in a new interval, and the voltage of each unit is readjusted using the redundant switching states. Thus, the output power equalization can be achieved in a shorter time. While maintaining the output characteristics of the existing modulation strategy, the new modulation strategy reduces the power equalization time and preserves the harmonic elimination characteristics of IPD. In addition, the optimized modulation strategy reduces the number of carriers, lowering the difficulty of digital control. Finally, simulation and experimental results are used to verify the correctness and feasibility of the new power equalization modulation strategy and its optimization.

Statistics

Show / Hide Statistics

Cumulative Counts from September 30th, 2019
Multiple requests among the same browser session are counted as one view. If you mouse over a chart, the values of data points will be shown.

Cite this article

[IEEE Style]

J. Gu, R. Cai, X. Zhou, C. Ding, W. Wang, "New power equalization modulation strategy for CHB seven‑level inverters," Journal of Power Electronics, vol. 23, no. 7, pp. 1063-1072, 2023. DOI: 10.1007/s43236-023-00606-2.

[ACM Style]

Jun Gu, Run-Zhe Cai, Xiang-Yu Zhou, Chao Ding, and Wei-Jian Wang. 2023. New power equalization modulation strategy for CHB seven‑level inverters. Journal of Power Electronics, 23, 7, (2023), 1063-1072. DOI: 10.1007/s43236-023-00606-2.