Short-Circuit Calculation and Protection Adaptivity Analysis Method for Power Systems with Inverter-Based Sources

With the large-scale integration of inverter-dominated renewable energy sources into the power grid, traditional short-circuit calculation models and protection-setting methods based on synchronous generators can no longer meet the requirements of modern power systems. To accurately analyze the short-circuit characteristics and relay protection adaptability of grids containing inverter-based sources, this paper proposes a dedicated method for short-circuit calculation and protection adaptability analysis. First, in consideration of the latest national standard requirements for low-voltage ride-through control of new energy sources, a corresponding equivalent fault-calculation model is established. Second, based on the inverter-based source equivalent model, a complete fault-calculation procedure and relay protection adaptability analysis method are developed to assess the adaptability of existing protection devices. Finally, the effectiveness of the proposed method is validated through simulation, providing technical support for the proper setting and reliable operation of relay protection in power systems with high renewable penetration.