Analysis of induction generators connection impact on voltage stability of electric power systems

Abstract

The voltage collapse in electric power systems is a problem that deserves special attention since it can lead to power supply interruptions and even to wide-area blackouts. To avoid the occurrence of this phenomena, a large number of studies must be carried out involving a huge number of computational costly simulations. In this context, the computational package MATPOWER, based on MATLAB, represents a good option to deal with these simulations in the academic level, because it is free and open-source software. Due to these reasons the MATPOWER has been adopted in the Power Systems Laboratory of UNICAMP to conduct power flow and voltage stability studies, in order to fulfill the objectives of the tematic project number 04/07567-7, granted by FAPESP. The objective of this project is to extend the usage of the MATPOWER to investigate the contradictory nature of induction generators when connected to the distribution grid to supply active power. On the one hand, these additional active power injections help to supply the local demand and, thus, reduce power losses and contribute to avoid an overloaded system condition, increasing the nodal voltage magnitude. On the other hand, this type of generator consumes reactive power from the grid and, consequently, has a negative impact on the voltage profile. By doing exaustive simulations in well-known electric power networks (IEEE-14, 30 and 118 buses networks), this work intends to assess the impacts on the proximity to the voltage collapse caused by the inclusion of multiple induction generators in different points of the system. (AU)