Anbuselvi VELU SHANMUGAM, Somasundaram PERIYASAMY, Kumudini Devi PANDU RAGURU

Loss minimization in wind farm integrated AC/DC system by optimal injections and droop settings of VSC-MTDC systems

In this paper, a modified optimal power flow (OPF) model, incorporating a voltage source converter-based multiterminal DC (VSC-MTDC) system, is proposed. The OPF is formulated to minimize the losses, steady state voltage deviations, and overloading of the AC/DC system. The control variables considered in this modified OPF model are power injection into the DC system and droop settings. Optimal injection patterns for different wind power penetrations and optimal droop settings are evaluated for wind farm side converters and grid side converters, respectively. Wind power penetrations are routed into AC and DC lines in different proportions to optimize the flows in AC/DC lines. The VSC-MTDC system, embedded on a practical utility system, is considered for the analysis. The results reveal that the losses are significantly reduced and flows in the AC and DC networks are optimally controlled to maximize the evacuation capability of the AC/DC system.

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