Executive Summary : | In the three-phase four-wire (TPFW) distribution system, load correction and power injection utilizing a grid-connected voltage source inverter (VsI) have been discussed in the literature. In conventional single VsI-based DsTATCOM has a number of limitations, including the need for a high dc-link voltage, a larger filter size, and an inverter with a higher rating, as well as less reliability. Additionally, if the active power supplied by the grid fails, either real power transfer or reactive power compensation will impair the VsI. A grid-connected dual two-level voltage source inverter (GCDTL-VsI) to enhance the power quality and reliability of the distribution system. The proposed GCDTL-VsI reduces the dc-link voltage, switch count, and switching losses without affecting the compensation capability compared to existing approaches, and also improves reliability, and reduces the filter size and cost of the system, due to the reduction dc-link voltage rating. During low power injection of VsI-1 to maintain rated dc-link voltage at the input terminal causes stress on the inverter switches and switching losses. Therefore, to alleviate the stress of inverter switches and switching losses to use an adaptive control scheme to reduce the dc-link voltage under low power injection. In GCDTL-VsI, a model predictive control (MPC) with multi constraint technique is used to generate the switching pulses, balancing the dc-link capacitor voltages and reducing the switching frequency. And also, to reduce the complexity of the weighting factor selection. |