Admissible HVDC infeed capacity evaluation of receiving-end power grids

Abstract

To fulfil the cross-regional bulk power delivery of renewable energy and alleviate the power shortage pressure of load centers, a number of line-commutated converter-based high voltage direct current (LCC-HVDC) transmission projects have been deployed in worldwide. Due to the system-wide operating risk sharply escalated with the intensively infeed of multiple large-capacity HVDC links, a vital knowledge gap exists in understanding the maximal admissible HVDC infeed capacity (AHIC) of receiving-end power grids. To tackle this issue, this paper proposes a novel AHIC evaluation method, which determines the maximal allowed total number and capacity of HVDC links that the receiving-end grid can accommodate while taking into account multi-preconceived fault security requirements. An improved dynamic system strength criterion is developed to assessing the immunity of post-contingency HVDC commutation failures (CF), which creatively considers the support effect from all AC buses based on the voltage sensitivity. The original two-stage model is decomposed into a construction master problem and an operation optimization subproblem, and then being iteratively solved using the generalized Benders decomposition algorithm. The effectiveness of the proposed approach is demonstrated on a modified IEEE RTS-79 system and a practical large-scale system.