1.School of Electrical Engineering, Northeast Electric Power University, Jilin 132012, China;2.NARI Group Corporation (State Grid Electric Power Research Institute), Nanjing 211106, China;3.State Key Laboratory of Technology and Equipment for Defense Against Power System Operational Risks, Nanjing 210003, China

As the proportion of renewable energy replacing synchronous generators continues to rise, the system voltage support capacity decreases, and the voltage drop at the fault point can trigger large-scale renewable energy to enter low voltage ride-through (LVRT). In order to describe the stable operation risk after the power system fault disturbance and guide the selection of stability control measures, it is particularly important to quickly and accurately evaluate the LVRT risk of renewable energy caused by disturbances and the short-term active power impact of the system. Therefore, from the perspective of mechanism analysis, the transient support of the generators during faults and the reactive power support of renewable energy entering LVRT are firstly considered. The traditional voltage interaction factor method is improved, and an assessment method for the bus voltage drop of renewable energy during fault disturbances suitable for large-scale power grids is proposed. Furthermore, based on the transient power response characteristics of renewable energy at the electromechanical scale, a rapid evaluation method for the short-term active power impact of LVRT of system large-scale renewable energy is proposed. Finally, taking the New England 39-bus system with renewable energy as an example, the effectiveness of the proposed assessment method for the short-term active power impact is verified through simulation.

This work is supported by State Grid Corporation of China (No. 5100-202440016A-1-1-ZN).