SEMINAR: Moving Bits Not Watts: Geographically Coordinated Primary Frequency Control
Primary Frequency Control (PFC) is a fast acting mechanism used to ensure high-quality power for the grid that is becoming an increasingly attractive option for load participation. Due to speed requirement and other considerations, it is often desirable to have distributed control laws. Current distributed PFC designs assume that the costs at each geographic location are independent. However, many networked systems, such as those for cloud computing, have interdependent costs across locations and therefore need geographic coordination. In this talk, I will discuss distributed control laws designed for interdependent, geo-distributed loads in PFC based on the optimality conditions of the global system and the subgradient method. The controlled frequencies are provably stable, and the final equilibrium point is proven to strike an optimal balance between load participation and the frequency’s deviation from its nominal set point. The case with a significant communication delay for control is also analyzed. We evaluate the proposed control laws with realistic numerical simulations. Under current technology, the proposed control laws achieve a convergence time comparable to that in the distributed control with independent costs. Results also highlight significant cost savings over existing approaches under a variety of settings.
Assistant Professor, Stony Brook University (SUNY @ Stony Brook)
Zhenhua Liu is an Assistant Professor in the Department of Applied Math and Statistics and the Department of Computer Science at Stony Brook University (SUNY at Stony Brook). He received his PhD in Computer Science from California Institute of Technology. He has received the SPEC Distinguished Dissertation Award (honorable mention), NSF Research Initiation Initiative Grant Award, and several best paper awards. His research interest lies in the intersection of optimization, big data systems, and energy. He has published over 30 papers and holds 2 US patents. His work with HP on Net Zero Energy Datacenter was named a Computerworld Honors Laureate.