Analysis of the effects of distributed generation sources on power grid reliability

Distributed Generation (DG) sources such as solar and wind power sources are gaining an increased popularity due to the various advantages they provide over the traditional fossil-fuel-based power generation sources. However, their effects on the system operation, while expected to be positive, are not yet fully understood. In this paper, we study the effect of adding DG sources to the grid on the overall system reliability. We simulate the effect of gradually injecting limited amount of real power at the load buses of the IEEE 14 bus system, and combine that with a single-transmission line contingency to study the effect of the DG sources on improving the operation of the grid in terms of reducing the stress on the transmission network, and reducing the total number of and the amount of overloads that could possibly occur in the transmission lines, due to the line contingencies. Our results show a general improvement in the operation of the power grid, due to the addition of the DG sources, but also shows that the amount of injected power has to be limited to generally small values, and in some cases should be planned in a way that keeps in mind the capacities of the lines in the transmission network.