Fast Economic Dispatch by Identifying Active Security Constraints Based on Sparse Polynomial Chaos Expansion

In order to promote the optimal allocation of resources across the country, an inter-provincial and intra-provincial bi-level electricity market operational mode is gradually formed in China. In the electricity market, security-constrained economic dispatch (SCED) is an important procedure to realize market clearing. However, SCED problem with N-1 scenarios has a great number of security constraints, which severely affect the computation efficiency. To deal with the above problem, an active security constrain identification method is proposed by utilizing sparse polynomial chaos expansion (SPCE) in this paper. First, a bi-level electricity market economic dispatch model is established including N-1 security constraints. Then, a SPCE-based surrogate model for SCED is established based on historical data. By using the surrogate model, the active N-1 security constraints are identified in advance, which would significantly reduce the number of iterations for solving the SCED problem. Finally, an interconnected test system with multiple sending end power grids and receiving end power grids is constructed using IEEE 39-bus and 118-bus systems. Also, the effectiveness of the proposed method is verified by simulation.