Abstract：At the AC side, the load tap changing(LTC) transformer branch is represented by introducing an artificial node located between an ideal transformer and its series impedance. The artificial node voltage can then replace the tap ratio of LTC to express the LTC branch power equations. At the DC side, some variables corresponding to the converter branch are introduced to express the DC equation, such as the AC node voltage magnitude, current magnitude, et al. The coupling equations integrate the quadratic AC and DC equations from the different coordinates into a united quadratic AC-DC load- shedding model to restore the feasible solution of the power flow. The predictor-corrector primal-dual interior point method is used to implement the optimization problem. The Hessians in this model are constant and need to be calculated only once in the entire optimal process, which speed up the calculation greatly. Numerical simulations indicate that the proposed model is corrective and effective, and gives a power flow measure for unfeasible cases.
聂永辉,杜正春,李崇涛,李天云. 恢复潮流可行的交直流电力系统切负荷新模型[J]. 电工技术学报, 2015, 30(4): 209-215.
Nie Yonghui,Du Zhengchun,Li Chongtao,Li Tianyun. A New Load-Shedding Model to Restore AC-DC Power Flow Feasibility. Transactions of China Electrotechnical Society, 2015, 30(4): 209-215.
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