Increasing Transmission System Operation Flexibility using Power Flow Controlling Devices

Name: Priyanko Guha Thakurta

•   Prof. dr. ir. Ronnie Belmans (promotor)
•   Prof. dr. ir. Dirk Van Hertem (mede-promotor)
•   Prof. dr. ir. Dirk Van Hertem (co-promotor)

Managing the security of a power system poses a big challenge for the Transmission System Operators (TSOs) in the present days due to large amount of renewable energy source integration into the system. Congestion is now a frequent issue in a meshed power system like that in Europe, due to increased market competition after decentralization and high integration of renewables. This demands the existing transmission infrastructure to be expanded, but serious limitations are posed mainly due to the \enquote{not in my backyard} attitude. Another major aspect of congestion management is the incurred cost to the TSOs for generation re-dispatch in the decentralized environment. Hence, TSOs are forced to find other means of managing congestion, keeping the costly actions as their last means. Moreover, the existing grid has to be operated more flexibly in order to integrate more renewables, thereby diverting flows to non-congested areas in the system.

Traditional N-1 principle for guaranteeing security of the power system will no longer be sufficient in the future due to enormous renewable integration into the system, as the cumulative forecast error can be significantly large. This, in turn, leads to serious challenges for the system operators to plan the operation of their systems day-ahead for real-time operation. Risk-based methods need to be developed in such a case in order to circumvent the limitation of the current approach of system security in the presence of increased renewables.

Power flow controlling devices (PFCS) have gained increasing attention among the TSOs in Europe. Many of these devices are installed and operated mainly to limit loop flows and manage transit flows through their systems. These devices are also used to manage critical contingencies in the system, but their operation mainly lies on the operator expertise. These devices also have a critical impact on the neighboring interconnected system, as these devices can create congestion and endanger system security of the neighboring grids if not controlled in a coordinated manner.

This thesis proposes algorithms to manage security and handle contingencies in the system with the help of already installed PFCs in a coordinated manner. It is also shown that operating the grid flexibly by these devices indeed helps integrating more renewables and handling more uncertainties in the system. A novel risk-based methodology is also developed in this thesis with which the system operators can learn the optimal operation point in their day-ahead operational planning, making maximum use of the system with a given confidence that the uncertainties present in the system due to renewables do not cause system overloads. It is also shown that the confidence can be significantly increased by a coordinated control of the PFCs.

https://lirias.kuleuven.be/handle/123456789/485485

•   Prof. dr. ir. Ronnie Belmans (promotor)
•   Prof. dr. ir. Dirk Van Hertem (mede-promotor)
•   Prof. dr. ir. Dirk Van Hertem (co-promotor)
•   Prof. dr. ir. Herman Neuckermans (voorzitter/chairman)
•   Prof. dr. ir. Ruth Vazquez Sabariego (secretaris/secretary)
•   Prof. dr. ir. William D'haeseleer
•   Prof. dr. Wil Kling , Eindhoven University of Technology
•   Prof. dr. Mikael Amelin , KTH
•   Prof. dr. Dirk Westermann , Technische Universität Ilmenau