Impact of distributed generation on the stability of electrical power systems

This paper aims at analysing the potential impacts that distributed generation might have on the stability of electrical power networks. In particular, the performance of a power system with significant penetration of distributed resources is described to assess different types of stability of the bulk network. For this purpose, a hypothetical network is simulated, assuming a large number of fuel cells and micro-turbines as dispersed units in the low-voltage area. The investigation is carried out at constant load demands but with different contributions from fuel cells and micro-turbines. Thus, the rated and supplied powers of the conventional synchronous generators are adjusted to achieve the power balance in the network. With each penetration level of the distributed generation, the performance of the network is studied and different stability classes are analysed. The results are compared with the performance of the network without any distributed generation, as a reference case, to highlight the influence of penetration levels of such units on the stability of the entire network.