A Parameter Design Method for SVC Considering the Impedance Interaction Between Inverters and Reactive Compensation Devices

ABSTRACT Distributed generation (DG) aggregation points are typically equipped with reactive compensation devices to maintain voltage stability. However, improper parameter design may cause harmonic oscillations due to interactions between the device and inverter impedance. This paper investigates the impedance interaction between the inverter and reactive power compensation device, with the goal of enhancing system damping. A parameter design method for static var compensators (SVCs) is proposed to balance power quality requirements with harmonic oscillation suppression. First, a port impedance model of the inverter and SVC is established to analyse the interaction mechanism. The system's characteristic roots are obtained using modal analysis. Based on these results, system damping is calculated to quantify the impact of SVC integration on stability. Furthermore, for multi‐inverter grid‐connected systems, an SVC parameter optimisation procedure based on particle swarm optimisation (PSO) is developed. This approach considers reactive power capacity requirements and adopts improved system damping as a design objective to achieve a balanced provision of reactive power support and resonance suppression. The effectiveness of parallel SVCs in suppressing multimodal resonance peaks and improving system damping is validated through both qualitative and quantitative analysis. Simulation and experimental results confirm that the proposed method achieves both power quality optimisation and harmonic oscillation suppression.