Real-time Phase-wise Reactive Power Control of SVC for Alleviating Phase Imbalance in Distribution Networks

This paper proposes a robust reactive power control method for Static Var Compensator (SVC) systems under input phase variation and load unbalance. Conventional SVCs regulate total reactive power and thus fail to compensate phase-by-phase reactive power when unbalanced conditions occur. To address this limitation, the proposed method employs a Dual Second-Order Generalized Integrator (DSOGI) to extract in-phase and quadrature components of three-phase voltages and currents, enabling accurate phase tracking and per-phase reactive power estimation. The extracted quantities are used to generate independent firing-angle commands for each TCR branch. PSIM simulations and DSP-based experiments verify that the proposed method achieves unity displacement power factor in all phases, outperforming existing control approaches.