M. Heydaripour, A. Akbari Foroud,
Volume 8, Issue 4 (12-2012)
Abstract
Congestion in the transmission lines is one of the technical problems that appear particularly in the deregulated environment. The voltage stability issue gets more important because of heavy loading in this environment. The main factor causing instability is the inability of the power system to meet the demand for reactive power. This paper presents a new approach for alleviation congestion relieving cost by feeding required reactive power of system in addition to re-dispatching active power of generators and load shedding. Furthermore with considering different static load models in congestion management problem with both thermal and voltage instability criteria, tries to the evaluated congestion management cost become more real, accurate and acceptable. The voltage stability is a dynamic phenomenon but often static tools are used for investigating the stability conditions, so this work offers new method that considers two snapshots after contingency to consider voltage stability phenomena more accurate. This algorithm uses different preventive and corrective actions to improve unsuitable voltage stability margin after contingency. The proposed method is tested on IEEE 24-bus Reliability test system, the simulation results shows the effectiveness of the method.
F. Amini, R. Kazemzadeh,
Volume 13, Issue 1 (3-2017)
Abstract
Development of distributed generations’ technology, trends in the use of these sources to improve some of the problems such as high losses, low reliability, low power quality and high costs in distributed networks. Choose the correct location to install and proper capacity of these sources, such as important things that must be considered in their use. Since distribution networks are actually unbalanced and asymmetric consumption loads are different, so in this paper with optimal placement and sizing of distributed generation sources that dependent on the load model and type of load connection and the uncertainties which caused by the generated power of wind turbines and solar panels, the positive effects of these sources have been examined on unbalanced distribution network. Hence with linear three-phase unbalanced load flow method and IPSO algorithm, allocation of distributed generation sources in IEEE standard of 37 bus unbalanced network have been done. Obtained results show improvement of voltage profile in each phase and reduction of network power losses and buses’ voltage unbalance factor.