PROJECT TITLE :

Advanced Voltage Support and Active Power Flow Control in Grid-Connected Converters under Unbalanced Conditions - 2017

ABSTRACT:

Supporting the grid and improving its reliability have recently become major necessities for massive distributed generation units. Beneath most grid faults, the accuracy of the ancient voltage support schemes (VSSs) is dramatically affected because of the existence of the zero-sequence voltage. Also, the ancient VSSs have been used only within the STATCOM applications, where the active power is zero. This paper proposes a sophisticated VSS in the converter-interfaced units, called zero-sequence compensated voltage support (ZCVS), to accurately regulate the three-section voltages of the affiliation point inside the pre-set safety limits. The proposed theme not solely compensates the zero-sequence component however also considers the active power injection. Unlike the traditional ways, the proposed VSS is tailored even in resistive distribution systems. The contribution of this paper is, however, ternate. As the second contribution, the restricted active power oscillation (LAPO) is proposed to be augmented to the ZCVS. This feature limits the oscillation to a specified price that provides an adjustable dc-link voltage oscillation setting whereas simultaneously supporting the ac host grid, even under severe unbalanced faults. Third, the maximum active power delivery (MAPD) to the ac grid is additionally formulated for the ZCVS. The successful results of the proposed support scheme and complementary ways are verified using selected simulation and experimental test cases.