Voltage Magnitude and Voltage Stability Margin Optimization Through Allocation and Sizing of SVCs via VNS Algorithm

An effective approach to address challenges in voltage regulation is the allocation of equipment that provide fast-responding reactive power support to the power system. This paper presents an optimization approach for the strategic allocation of Static VAR Compensators (SVCs), aiming to enhance voltage magnitude and stability margin. The proposed methodology incorporates Voltage Severity Index (VSI) and Voltage Security Margin (VSM) analysis to ensure operational reliability and prevent voltage collapse under different system conditions. The optimization model, formulated as a mixed-integer non-linear problem, considers key SVC operational characteristics, including the slope of the V/Q operating curve, reactive power capacity, the voltage magnitude reference value for the controlled bus, and the possibility of remotely controlling the voltage magnitude of a specific bus. Given the complexity of the problem, a Variable Neighborhood Search (VNS) algorithm was developed and tailored to efficiently explore the solution space and determine high-quality strategies for SVC placement and sizing. Simulation results on a 107-bus test system demonstrate the effectiveness of the proposed approach in mitigating voltage violations and enhancing stability margins for multiple operational conditions. The solution found by the proposed algorithm enhances the power system’s performance by 54% VSI-wise and up to 540% VSM-wise.