http://13.232.72.61:8080/jspui/handle/123456789/106 2026-04-03T18:12:01Z http://13.232.72.61:8080/jspui/handle/123456789/796 Title: Analysis of Importance Sampling and Contingency in Electric Power System Security. Authors: Nandini, B. R.; Prakash, R.; Lekshmi, M. Abstract: Power system security has become one of the most important issues in power system operation due to intensive use of transmission network and it is strongly tied with contingency analysis. However with the introduction of more variable generation sources such as wind power and due to fast changing loads power system security analysis will also have to incorporate sudden changes in injected powers that are not due to generation outages. The probability of failure induced by changes in grid state is evaluated by the Monte Carlo simulation method. A comparison to crude Monte Carlo (CMC) and Importance sampling (IS) method is performed for standard IEEE-33 bus system. Importance sampling method indicates a major increase in simulation efficiency by reducing number of samples. 2013-06-01T00:00:00Z http://13.232.72.61:8080/jspui/handle/123456789/795 Title: Case Study On Fuzzy Logic Based Network Contingency Ranking. Authors: Ramesh, E.; Prakash, R.; Lekshmi, M.; Yogeesh, S. Abstract: Security assessment of a power system is very important function to detect any violation in the system and to ensure secure operation of the system in deregulated environment. Contingency ranking is the process of indexing the possible contingencies of the system on the basis of their severity. The method proposed in this research work takes the consideration of both apparent power overloading and voltage violations at the same time. From which Performance Indices (PI) is obtained. Masking effect is a very important factor which results in misclassification of contingencies which can be eliminated by using fuzzy logic. The proposed approach, in addition to real power loadings and bus voltage violations, voltage stability indices at the load buses are also used as the post-contingent quantities to evaluate the network contingency ranking of a Practical IEEE30 bus system. 2013-07-01T00:00:00Z http://13.232.72.61:8080/jspui/handle/123456789/794 Title: Voltage Source Converter Based HVDC Transmission Authors: Shri harsha, J.; Shilpa, G. N.; Ramesh, E.; Dayananda, L. N.; Nataraja, C. Abstract: High Voltage Direct Current system based on Voltage Source Converters (VSC-HVDC) is becoming a more effective, solution for long distance power transmission especially for off-shore wind plants and supplying power to remote regions. Since VSCs do not require commutating voltage from the connected ac grid, they are effective in supplying power to isolated and remote loads. Due to its advantages, it is possible that VSC-HVDC will be one of the most important components of power systems in the future. Power transmission using AC system over the past years has proven to be robust and efficient. One main problem with respect to AC power transmission is the complexities involved in precise power controllability. This problem may be overcome by using VSC based HVDC system of transmission. In the present work, possibility of using VSC based HVDC transmission for evacuating power is explored. 2012-09-01T00:00:00Z http://13.232.72.61:8080/jspui/handle/123456789/793 Title: Modeling and Simulation of Voltage Source Inverter Based on Space Vector Modulation Technique for Grid Connection Authors: Kulkarni, Harshavardhan Vijay Abstract: In this paper modeling and simulation of three phase two level 100 kVA space vector modulation controlled voltage source inverter and its comparison with sinusoidal pulse width modulation controlled VSI for L-C filter requirements, L-C and L-C-L filters are designed and simulation results for isolated grid are presented. The simulation is done using MatLab/Simulink® 7.4.0.287 (R2007a).The need for inverters in distributed generation systems reveals the significance of achieving low distortion, high quality power. The designed filter should attenuate switching frequency components and should meet the utility voltage, current and distortion limits. 2014-04-01T00:00:00Z