A method for constructing a risk assessment indicator system for grid operation considering distributed new energy sources

The increasing penetration of distributed new energy sources presents subversive challenges to the operation and control of power system. It is of great significance to construct an operation indicator system for power grid considering distributed new energy sources to guide the safe and stable operation of large power grid. This paper first analyzes the impact of the fluctuations in distributed new energy output on active power balance across the grid， the balance between generation and consumption in different partitions， and the reactive power exchange between the main and distribution networks. Next， considering the replacement of conventional units and the weaker disturbance resistance of new energy units， the mechanisms behind transient voltage and frequency instability are revealed as the penetration of distributed new energy sources increases. Based on this analysis， a risk assessment indicator system is established， encompassing balance risk， safety and stability risk， steady-state regulation capability， and stability control capability. The risk control capability indicator is introduced to characterize the risk regulation levels of various control resources across different time scales. Furthermore， by incorporating probability method into the risk indicator assessment model， probabilistic discrete scenarios are used to provide technical support for dispatch operators in developing appropriate control strategies. Finally， the effectiveness of the proposed operation indicator system and evaluation method is validated through case studies on both standard test systems and actual power systems.