Е-Публикации
Технически университет - София

Abstract: Modern distribution networks are increasingly affected by the phenomenon of harmonic resonance due to the connection of inverter generation and nonlinear loads. This paper proposes an analytical model for assessing the resonance conditions determined by the equivalent inductive and capacitive characteristics of the network. The model is applied to a typical distribution power line with predominantly long overhead lines, cable sections and connected photovoltaic power plants. The results show that the connection of inverter generating capacities shifts the resonant frequencies to lower harmonic orders, increasing the risk of harmonic amplification and unintended protection tripping. The proposed model provides a practical tool for preliminary assessment of resonance in modern distribution systems.

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