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Abstract
Quality and stability are two important issues for the secure operation of power systems. Electricity grid upgrades, and especially the construction of new transmission lines and loads cannot keep pace with the growing power plant capacity and energy demand for various reasons. The changing characteristics and new loads of power systems continue to provide new challenges to the system designers and operators. Plug in hybrid electric vehicle (PHEV) is such a load which can have huge impact and opportunities for power systems. The first contribution of this work is to identify the charging effect of dynamic PHEV in power system. A single machine infinite bus (SMIB) system, solar power system and an electricity distribution system are used for this purpose. A dynamic load model of PHEVs is introduced here based on third order battery model. To determine the system adequacy, it is necessary to do a micro level analysis to know the PHEVs load impact on the grid. The stability analyses of the power grid demonstrate that it is important to consider the dynamics of PHEVs load. The second and unique contribution of this thesis is the design of virtual active filter for power system using V2G technology. Nonlinear loads, inverters and converters absorb reactive power from the connected bus. Compensation of reactive power is essential in power system. In this thesis the Vehicle to Grid (V2G) technology is used to design virtual active filter based on instantaneous power theory (p-q) theory. The potential of a low-cost solution that utilizes the reactive power and filtering capabilities of plug in vehicles parked in charging stations is investigated. Simulations are performed for various power system networks to demonstrate that the proposed virtual active filter improves the power quality maintaining the IEEE standard. The other significant contribution of this research is to design FACTS devices using V2G technology which can fulfil multiple power flow control objectives such as needs of reactive shunt compensation, phase shifting and series compensation. However FACTS are quite expensive and therefore are not widely used. In this dissertation the potential of PHEV in a V2G mode of operation is explained, which gives a low-cost solution for designing a virtual FACTS devices (UPFC, UPQC, DVR) using PHEV charging station. Finally, a benchmark distribution network has been used to verify the performance of the proposed filter and FACTs devices in grid.
