The new energy generation represented by wind power is the most realistic strategic choice to achieve the goals of carbon peaking and carbon neutrality. To absorb renewable energy electricity in power grids a new probabilistic evaluation method for available transmission capacity in transmission systems is proposed based on joint cumulants， and a decision model for risk available transmission capacity based on expected quantiles is proposed accordingly. As a vital component of ATC calculation， the transmission reliability margin (TRM)， as a reserved transmission capacity， reflects the impact of uncertainty factors on transmission capacity. However， in traditional calculation methods， TRM is determined through deterministic or probabilistic methods， which is difficult to reflect the risks brought by large-scale wind power consumption to ATC and cannot meet the requirements for transmission capacity risk management. Firstly， to address the issue that the cumulative method requires variables to be independent of each other and cannot consider the correlation of wind power output， a joint cumulative method combined with FGM Copula function is proposed to characterize the correlation of wind power output; Secondly， for the probabilistic assessment of available transmission capacity， a probabilistic assessment model for available transmission capacity is established by combining the partition integration method and the Comish Fisher expansion; Finally， in response to the problem that decision methods based on value at risk only consider the probability achieved at the tail of the probability distribution and cannot describe the risks generated throughout the distribution， a risk available transmission capacity index based on expected quantiles is proposed， and its evaluation process is proposed. Verify the feasibility and practicality of the proposed indicators and models through case analysis.

I. Introduction
II. Risk Available Transmission Capacity Decision Model Based on Expected Quantile
III. Case Analysis
A. Test System and Data
B. Assessment Results and Analysis of Transmission Capacity
C. Comparative Analysis
IV. conclusion
V. List of Abbreviations

Kader S M ,Mahmuudh R ,Han X , et al.Decision Model of Transmission Capacity Based on Expected Quantile for Wind Farm[J/OL].太原理工大学学报,1-8[2024-11-19].http://kns.cnki.net/kcms/detail/14.1220.n.20241018.1849.006.html.