Static Voltage Stability Analysis and Improvement Method for Distribution Network Considering DG

In new distribution systems, the proportion of distributed renewable energy generation is gradually increasing. Existing methods for static voltage stability analysis struggle to accurately reflect the impact of distributed generation output. First, this paper introduces robustness indices to quantify the impact of active and reactive power output fluctuations from distributed generation on load buses, based on the L-index. Second, a static voltage stability indicator system is constructed. Based on the characteristics of the indicators, definitions for voltage stability weak bus, active power vulnerable bus and reactive power vulnerable bus are established. Third, an optimization model to enhance static voltage stability is developed specifically for these buses. The Pareto front of the solutions obtained by it based on the NSGA-III algorithm includes the optimal solutions under different index preferences, and then it is achieved by adjusting the power output of the power source. Last, the effectiveness of the indicator system and the enhancement methods are validated through the IEEE 118-bus system.