Open AccessExtended ADMMs for RPO of large‐scale power systems with discrete controls
Author(s) -
Zheng Jiabin,
Liu Mingbo,
Lu Wentian,
Xie Min,
Zhu Jianquan
Publication year - 2018
Publication title -
iet generation, transmission and distribution
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.92
H-Index - 110
eISSN - 1751-8695
pISSN - 1751-8687
DOI - 10.1049/iet-gtd.2017.1257
Subject(s) - mathematical optimization , nonlinear programming , convergence (economics) , integer programming , quadratic programming , computer science , correctness , optimization problem , electric power system , integer (computer science) , mathematics , nonlinear system , algorithm , power (physics) , physics , quantum mechanics , economics , programming language , economic growth
The reactive power optimization (RPO) problem of power systems is a mixed‐integer nonlinear programming problem, which can be computationally expensive. This paper applies the alternating direction method of multipliers (ADMM) to solve it. By duplicating discrete control variables with one copy allowed to vary continuously, the RPO model is formulated as a modified model in which the objective function and constraints have a separable structure with respect to the continuous and discrete variables, except for the coupling constraint. We then applied the ADMM to solve this model with the separable structure, and hence the original problem is converted into two optimization sub‐problems, which are nonlinear programming (NLP) and mixed‐integer quadratic programming (MIQP) problems, respectively. To improve the convergence of the algorithm, we proposed an extended ADMM by adding the upper and lower limits on state variables into the MIQP sub‐problem based on the sensitivities obtained in the NLP sub‐problem. We also established a mechanism to filter out inactive inequality constraints in the MIQP sub‐problem to improve computational speed. Moreover, numerical results tested on IEEE test systems and a real 739‐bus system have shown the correctness of the proposed method and its adaptability for power systems with different sizes and configurations..