M. Aghamohammadi, S. S. Hashemi, M. S. Ghazizadeh,
Volume 7, Issue 1 (3-2011)
Abstract
This paper presents a new approach for estimating and improving voltage stability margin from phase and magnitude profile of bus voltages using sensitivity analysis of Voltage Stability Assessment Neural Network (VSANN). Bus voltage profile contains useful information about system stability margin including the effect of load-generation, line outage and reactive power compensation so, it is adopted as input pattern for VSANN. In fact, VSANN establishes a functionality for VSM with respect to voltage profile. Sensitivity analysis of VSM with respect to voltage profile and reactive power compensation extracted from information stored in the weighting factor of VSANN, is the most dominant feature of the proposed approach. Sensitivity of VSM helps one to select most effective buses for reactive power compensation aimed enhancing VSM. The proposed approach has been applied on IEEE 39-bus test system which demonstrated applicability of the proposed approach.
D. S. Javan, H. Rajabi Mashhadi,
Volume 7, Issue 4 (12-2011)
Abstract
Deregulation of power system in recent years has changed static security assessment to the major concerns for which fast and accurate evaluation methodology is needed. Contingencies related to voltage violations and power line overloading have been responsible for power system collapse. This paper presents an enhanced radial basis function neural network (RBFNN) approach for on-line ranking of the contingencies expected to cause steady state bus voltage and power flow violations. Hidden layer units (neurons) have been selected with the growing and pruning algorithm which has the superiority of being able to choose optimal unit’s center and width (radius). A feature preference technique-based class separability index and correlation coefficient has been employed to identify the relevant inputs for the neural network. The advantages of this method are simplicity of algorithm and high accuracy in classification. The effectiveness of the proposed approach has been demonstrated on IEEE 14-bus power system.
Lambe Adesina, Ahmed Olaoye, Olalekan Ogunbiyi, Dalegan Dayo,
Volume 22, Issue 0 (3-2026)
Abstract
Power system analysis is crucial for network planning and operation, requiring knowledge of network parameters to assess system behavior. Power flow and contingency evaluations are key tools for monitoring and managing power systems. This paper focuses on analyzing an electric power system using power flow and contingency analysis, with a case study of a regional transmission network. Power flow solutions and contingency analysis were conducted using PSS software, evaluating the network’s performance before and after various N-1 contingency cases. Voltage and line loading violations were analyzed, and vulnerable buses were identified. The study explored the interaction between STATCOM and the regional network during N-1 contingency scenarios, highlighting its role in improving voltage stability and reducing line loading violations. To assess voltage collapse risk and the impact of outages on reactive power margin, QV curves were plotted for the most affected buses. STATCOM devices were placed on the affected buses to optimize performance, mitigating the N-1 contingency effects. The application of STATCOM significantly improved the voltage profile and increased the power handling capacity of the network, both before and after the contingency events. This work demonstrates the effectiveness of STATCOM in enhancing stability and capacity of the network under contingency conditions.
