# A Fast, Decentralized, Self-Aligned Carrier Method for Multicellular Converters +
## 6 Conclusions  
In order to reduce the system configuration and reconfiguration times as well as to overcome some restrictions in updating rules of the conventional decentralized control method, two fast control methods are proposed in this paper, namely decentralized self-aligned phase-shifted carrier (DSA-PSC) and decentralized self-aligned level-shifted carrier (DSA-LSC). The algorithms of both methods are similar, where a cell controller sends to the next one the information of its angle/level, its index number, and the total number of activated cells of the converter. Then, each cell controller determines the inter-carrier phase-shift/elementary level shift and updates its own carrier-phase/carrier-level based on the received information. The proposed control algorithm can be easily implemented with DSP, can self-align the carriers rapidly and exactly, and can be applied to both phase-shifted and level-shifted multi-cell converters with any number of carriers. Simulation  
Figure 47: Reconfiguration system response when removing cell 4, (**a**) conventional method; (**b**) proposed DSA-PSC method.  
Figure 48: Reconfiguration system response when reinserting cell 4, (**a**) conventional method; (**b**) proposed DSA-PSC method.  
and experimental study are provided to validate the feasibility and the effectiveness of the proposed DSA-PSC and DSA-LSC methods.  
It can be concluded that the main advantages of the proposed DSA-PSC and DSA-LSC are: (1) the system can operate with any number of carriers (\(N\geq 1\)); (2) the system can start up from any value of carrier-phases or carrier-levels, including zero point; (3) in case a cell controller is inserted or removed, the system reaches the steady-state after predefined reconfiguration time (equal to \(2N\) time steps); (4) the simulation study confirms that the reduction of configuration time is the key advantage of the proposed DSA-PSC method in comparison with the conventional decentralized phase-shifted method, and this reduction becomes more significant with higher number of carrier \(N\); (5) simulation and experimental studies in case of a reconfiguration process for conventional and proposed methods also approve the advantages of the proposed DSA-PSC method in terms of lower reconfiguration time and zero inter-carrier phase-shifts relative error.  
All authors proposed and discussed the idea of this paper, performed the simulation, and implemented the experiment. All authors contributed to the writing of the manuscript, revised, and approved the final manuscript. All authors have read and agreed to the published version of the manuscript.  
This research and the APC were funded by the Vietnam National University Ho Chi Minh City (VNU-HCM) under grant number B2019-20-07.  
This research was funded by the Vietnam National University Ho Chi Minh City (VNU-HCM) under grant number B2019-20-07. We acknowledge the support of time and facilities from Ho Chi Minh City University of Technology (HCMUT), VNU-HCM for this study. We also thank Power Electronics Research LAB (HCMUT, VNU-HCM) and LAPLACE (INPT, Toulouse) for providing their precious collaboration.  
The authors declare no conflict of interest.