Risk quantitative assessment of emergency control measures to improve power grid transmission capacity

Cross-regional interconnection of power systems, large-scale integration of renewable energy and interaction between demand side and power systems are raising new challenges to the operation of a large scale power system, such as complexity, uncertainty. A risk quantitative assessment method of emergency control measures is proposed to improve power grid transmission capacity based on the study of risk assessment model. The cost of emergency control measures including generator tripping, load shedding and HVDC modulations, and stability control strategy affected by the Rule 599 are taken into consideration in this method. Several transient instability risk indexes are proposed to quantify the transient stability level of power systems. Also the influence of different control quality on risk values is analyzed. With considering both security and economy in the indexing of the cost of improving unit transmission capacity, evaluating and selecting emergency control measures comprehensively are achieved.