Development of a new methodology for determining the maximum network integration limit of distributed generation facilities

The energy sector has a very important place in world economies and electricity energy is increasing its share in this sector day by day. Increasing energy demand and rising environmental and economic concerns in recent years have created tendencies on clean energy use and high efficiency within the sector. As a result of that, power systems have been entered into a process of change. Distributed Generation (DG) is an innovative generation concept, which is brought by these changes. Enabling integration of renewable energy sources into power systems and reducing system losses have increased the attractiveness of DG systems and have led to the inrease their penetration in power systems. On the other hand, distributed generation can lead to various problems in power systems, as it is a production that is contrary to traditional power systems which are based on centralized energy generation and unidirectional power flow. One of these problems is voltage quality, which is very important in terms of power systems, is affected by the distributed generation integration. Distributed genaration units cause an increase in voltage at and around the integration point. Incorrectly planned DG integration may cause over voltages which is closely related to the capacity of the DG unit integrated into the system. DG planning is quite important, in order to achieve maximum benefits from DG and to minimize the possible problems. DG planning is a versatile issue and there is a wide literature on this subject. In this thesis study, it is aimed to express the relationship between the capacity of the DG systems and the voltage values of the system after DG integration through a mathematical model. After the detemination of such a mathematical model, it is possible to calculate the maximum DG integration capacity which will not cause overvoltage problems in the system, and this will be able to contribute to the literature as a calculation tool used in DG planning studies. In the literature, there are various mathematical models which are focused on the same purpose. However, in the course of the derivation of these models, various assumptions and omissions have been taken as basis, and they are all derived based on the zero load case of the system. This study is two stage and in the first stage, it is aimed to propose a new mathematical model by developing the mathematical models derived from the unloaded state of the system. Subsequently, it is aimed to obtain a mathematical model that can be used for including the loads and generators of the systems into the calculations. In order to test the capabilities of the proposed mathematical models, a variety of case studies have been performed on a 34-Bus radial test system. The obtained results show that; the mathematical model proposed for the zero load case of the system gives higher and more consistent results than the alternatives given in the literature.