Combinatorial Optimization of Alternating Current (AC) Electric Power Systems: Bridging Power Engineering and Computer Science
01 Dec, 2017 (Fri)
3:00 pm
Room 603, Chow Yei Ching Building

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Dr. Sid Chi-Kin Chau
Assistant Professor
The Masdar Institute in Abu Dhabi, UAE


In the era of dynamic smart grid with fluctuating demands and uncertain renewable energy, it is crucial to continuously optimize the operational cost and performance of electric power grid, while maintaining its state within the stable operating limits. Nonetheless, a major part of electric power grid is consisted of alternating current (AC) electric power systems, which exhibit complex behavior with non-linear operating constraints. The optimization of AC electric power systems is still a very challenging problem that baffles electrical power engineers.

The hardness of optimization problems of AC electric power systems stems from two issues: (1) non-convexity involving complex-valued entities of electric power systems, and (2) combinatoric constraints involving binary control decision variables. Without proper theoretical tools, heuristic methods or general numerical solvers had been utilized traditionally to tackle these problems, which do not provide theoretical guarantees to the true optimal solutions. There have been recent advances in applying convex relaxations to tackle non-convex problems of AC electric power systems. On the other hand, combinatorial optimization is rooted in theoretical computer science, which typically considers linear constraints, instead of those non-linear constraints in AC electric power systems.

To bridge power engineering and computer science, this talk presents a comprehensive study of combinatorial optimization of AC electric power systems with (inelastic) discrete demands. It covers approximation algorithms and inapproximabilty results for various settings. Through this talk, a foundation is established for the confluence of power engineering and computer science. This talk is based on a monograph to be published in Foundations and Trends in Electric Energy Systems by Now Publishers Inc.


Biography of the speaker:

Sid Chi­-Kin Chau is an assistant professor with the Masdar Institute in Abu Dhabi, UAE, which was established in collaboration with MIT. His primary research area is Internet-of-Things and cyber-physical systems for smart cities and smart energy systems, including smart grid, smart buildings, intelligent vehicles and transportation. He also researches in broad areas of wireless communications, algorithms, and big data analytics. Previously, He was a visiting professor with MIT, and a senior research fellow with A*STAR in Singapore. He received the Ph.D. from University of Cambridge and B.Eng. from the Chinese University of Hong Kong. He has been on the program committees of top conferences in computing systems for smart cities and energy networks, such as ACM e-Energy and ACM BuildSys. He is a TPC co-chair of ACM e-Energy 2018. Further information about his research can be found at


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