Planning and Energy Management of Energy Storage Systems in Active Distribution Networks

• Author / Creator

  Abdeltawab, Hussein MH

• This thesis discusses the techno-economic planning and operation of energy storage systems in active distribution power systems. Energy storage systems (ESSs) can participate in multi-services in the grid, such as energy arbitrage, renewable energy time-shifting, peak shaving, power loss minimization and reactive power support. The main objective is to enable the owner (a consumer or distribution company) to maximize profit while maintaining the power quality and respecting the operational constraints. In this thesis, energy storage planning is conducted by sizing and allocating both of stationary and mobile storage. With stationary storage sizing, the system operator owns the storage which increases the total profit by performing multi grid services including distribution system expansion, energy arbitrage, energy loss minimization, time shifting, and reactive power support. The optimization includes practical constraints for the battery dynamics, such as the state of charge, and the number of charging cycles. The power flow constraints are considered, and the bus voltage and branch ampacity are included. The sizing scheme includes other options, such as distributed generators, static VAr compensators, and other power-balancing services. The sizing scheme was tested by simulation on a real radial feeder in Ontario, Canada. The sizing problem was also investigated for mobile energy storage systems (MESSs). The second part of the thesis discusses the use of predictive energy management systems (EMSs) for different applications. First, a predictive EMS for a hybrid wind-battery system is discussed. The EMS provides more profit for the owner by including a practical method that considers the battery expended-life cost. The EMS determines the optimal charging cycles and state of charge that will achieve the maximum net profit for the hybrid system owner. A predictive EMS is also developed for a flywheel with a wind system. The flywheel regulates the hybrid system power and its rate to comply with the grid code. The EMS considers the flywheel power loss minimization as a factor in the optimization. A day-ahead EMS is designed for mobile storage to define the optimal dispatching buses and powers such that the distribution system owner’s profit is maximized. This objective is achieved by simultaneously performing power loss minimization, reactive power support, and energy arbitrage. Finally, the thesis demonstrates multi ESS participation in day-ahead markets by defining the robust operating zones in the distribution system. The uncertainties of loads and renewable resources are considered to define the safe dispatch levels for the distributed storage. Comparative case studies, conducted on a real active distribution system in Ontario, Canada, showed the effectiveness of the proposed planning and EMS algorithms.

• Subjects / Keywords

  • Active Distribution Systems
  • Energy Storage System
  • Energy Management Systems

• Graduation date

  Spring 2017

• Type of Item

  Thesis

• Degree

  Doctor of Philosophy

• DOI

  https://doi.org/10.7939/R3R49GN4Q

• License

  This thesis is made available by the University of Alberta Libraries with permission of the copyright owner solely for non-commercial purposes. This thesis, or any portion thereof, may not otherwise be copied or reproduced without the written consent of the copyright owner, except to the extent permitted by Canadian copyright law.