A note on versions:The version presented here may differ from the published version or from the version of record. If you wish to cite this item you are advised to consult the publisher's version. Please see the repository url above for details on accessing the published version and note that access may require a subscription. Abstract-This paper presents a new space vector modulation (SVM) strategy for matrix converters to reduce the commonmode voltage (CMV). The reduction is achieved by using the switch configurations that connect each input phase to a different output phase, or the configurations that connect all the output phases to the input phase with minimum absolute voltage. These two types of configurations always produce lower peak CMV than the others, especially the former ones that result in zero CMV at the output side of matrix converters. In comparison with the existing SVM methods, this strategy has a very similar software overhead and calculation time. Simulation and experiment results are shown to validate the effectiveness of the proposed modulation method in reducing not only the peak value but also the root mean square value of the CMV.

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The capability of quality-of-service (QoS) provisioning is of particular importance for multi-hop wireless networks when the real-time applications boost in current days. The scheduling and delivery of data packets in a deficient method may probably cause network congestion, which will in turn decrease the capability of QoS provisioning in the network. To this end, we propose a joint QoS provisioning and congestion control scheme for multi-hop wireless network in this paper based on our previous works of Differentiated Queueing Service (DQS) and Semi-TCP, which provide per-packet granular QoS and carry out efficient hop-by-hop congestion control, respectively. While DQS and Semi-TCP are studied separately, we investigate the arising issues in the joint scheme and propose possible solutions accordingly, including a fast estimation of the latest departure time, a method to handle overdue packets, and an adaptive ACK scheme, as well as the design of a shared database cross-layer architecture for the implementation in the protocol stack. Simulation results show that our proposal improves the network performance in terms of goodput, delivery ratio, and end-to-end delay significantly, particularly in the scenario of mobile users. Our discussion and simulation results both indicate that the proposed joint scheme is flexible and adaptive to the dynamic multi-hop wireless network environment.

In this paper, a modified decentralized finite control set model predictive control (FCS-MPC) scheme for the distributed energy resources (DERs) is proposed to improve the power management quality of the prosumers integrated microgrids under the condition of harmonic and unbalance loads. The proposed control strategy for the microgrids mainly consists of the power droop controller, the model predictive controller delay compensation, feedback correction and the unbalance compensation mechanism. The feedback correction method is used to correct the delay compensation, which effectively reduces the average switching frequency (ASF) and voltage total harmonic distortion (THD). By sharing the negative sequence reactive power of the microgrid, power distribution between the prosumers' DERs is improved. The DERs in the prosumers can be integrated without any communication wire. The transient response and robustness to parameter changes are far superior to hierarchical cascaded control. Moreover, the proposed control strategy can better suppress harmonic and reduce and share fundamental negative sequence reactive power under microgrid unbalance and nonlinear load conditions. Finally, the effectiveness of the proposed FCS-MPC control strategy is validated by time-domain simulation results and real-time tests with RT-Lab under the condition of unbalanced and nonlinear loads in the microgrids.INDEX TERMS Microgrids, finite control set (FCS), model predictive control (MPC), voltage source converter (VSC), unbalance and harmonics control.

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