چكيده به لاتين
The rapid development of different energy production and conversion technologies at the Distribution System (DS) level facilitates the integration of electrical, heating, and cooling DSs. This integration leads to the advent of the energy hub (EH) concept that introduces new approaches for meeting end-users various energy demands. EHs increase the flexibility of energy management and enhances the power system efficiency and reliability by coupling different energy producers, energy storage devices, and energy conversion technologies. The planning and operation of integrated DSs will affect the asset management of the Transmission System (TS), which in turn will change the electrical energy prices and investment decisions at the DS level. Then, the traditional sequential transmission and distribution system expansion approaches are not suitable for the modern power grid with integrated energy systems. Then, it is necessary to evaluate accurately the impact of integrating EHs across the distribution system on expansion planning of the upstream transmission network. Firstly, a centralized approach is discussed for coordinated expansion planning of the TS and EHs. The proposed framework is applied to find an optimal solution for the total investment, operation, and emission costs of the system. Then, two static and multi stage approaches are discussed for coordinated expansion planning of TS and integrated electrical, heating, and cooling DSs. In the following, the impact of electrical, heating and cooling load response programs in the static model of the coordinated Expansion planning of TS and energy hubs is discussed. The PhotoVoltaic panels (PVs), Wind Turbines (WTs), Combined Heat and Power Generation (CHP) units, boilers, as well as electrical and absorption chillers are considered investment candidates for coupling the electrical, heating, and cooling DSs. Moreover, the expansion planning of TS lines, electrical feeders, and heating and cooling pipelines are integrated into the proposed multi-stage. The first level of the proposed optimization approach deals with Transmission system Expansion Planning (TEP), while the second level develops Distribution system Expansion Planning (DEP). Total planning, operation, and emission costs are considered as the objective function for the first and second levels. Market clearing is done in the third level to update the Locational Marginal Prices (LMPs) for different Distribution System Operators (DSOs). DSOs across the power system tries to minimize their individual costs by investing in the EHs. The proposed models are tested on the modified conventional IEEE TSs comprising electrical, heating, and cooling DSs. The numerical study proves that the DSOs, connected to different nodes of the TS, reduce their operation and emission costs by investing in various types of energy resources. Moreover, the proposed schemes successfully reduces the total expected costs of the TSO and the whole system and successfully postpones the expansion of the TS.
