Investigation of effects of microturbines on power systems

The demand for economical and uninterruptible energy has increased with the advancement of technology. The importance of novel alternative electrical power systems has increased due to the increase in electric power demand and the increase in fuel costs, the decrease in fossil fuel reserves and the increase in greenhouse gas emissions etc. Distributed generation systems (DGS) are currently attracting a lot of attention as a solution to these concerns to provide low-cost energy, enable to use the renewable energy and to increase the efficiency and performance of electrical power systems. DGS can be used to meet the energy requirement in rural areas where there is no grid connection or to reduce the use of electricity from the grid by working in parallel with the grid in regions where the grid connection is available. DGSs consist of small modular distributed generation technologies, energy storage technologies, and energy management systems. DGSs can be composed of renewable energy technologies such as wind turbines and photovoltaics, as well as non-renewable but promising technologies such as microturbines and fuel cells. One of the distributed generation technologies, microturbines are a relatively new technology and offer many advantages to the user. Because microturbines can produce both electricity and heat on a small scale, they are one of the technologies that are widely preferred in DGS and CHP applications. The structure and working principle of microturbines are very similar to traditional gas turbines. It can work with different fuels such as natural gas, LPG, diesel, propane, biofuels and industrial gases. Depending on the shaft state of the generator and turbine, there are basically two types of microturbine generation system (MTGS) as the single shaft and split shaft turbines. In this thesis study, models of the single shaft and split shaft MTGSs have been presented which uses natural gas as fuel. Load tracking performance of developed models was analyzed for stand-alone and grid-connected mode under different scenarios. In addition, using the developed models, microturbine output power, fuel consumption and fuel cost could be observed depending on power system dynamics. These values were compared with between two models.