Load flow analysis is a significant tool for proper planning,operation,and dynamic analysis of a power system that provides the steady-state values of voltage magnitudes and angles at the fundamental frequency.However...Load flow analysis is a significant tool for proper planning,operation,and dynamic analysis of a power system that provides the steady-state values of voltage magnitudes and angles at the fundamental frequency.However,due to the absence of a slack bus in an islanded microgrid,modified load flow algorithms should be adopted considering the system frequency as one of the solution variables.This paper proposes the application of nature-inspired hybrid optimization algorithms for solving the load flow problem of islanded microgrids.Several nature-inspired algorithms such as genetic algorithm(GA),differential evolution(DE),flower pollination algorithm(FPA),and grasshopper optimization algorithm(GOA)are separately merged with imperialistic competitive algorithm(ICA)to form four hybrid algorithms named as ICGA,ICDE,ICFPA,and ICGOA.Performances of these algorithms are tested on the 6-bus test system and the modified IEEE 37-bus test system.A comparison among the proposed algorithms is carried out in terms of statistical analysis conducted using SPSS statistics software.From the statistical analysis,it is identified that on an average,ICDE takes less number of iterations and consequently needs less execution time compared with other algorithms in solving the load flow problem of islanded microgrids.展开更多
This research focuses on restructuring medium-level voltage(MLV)distribution systems by integrating distributed renewable energy resources(DER)at multiple feed points.It examines the impact of incorporating renewable ...This research focuses on restructuring medium-level voltage(MLV)distribution systems by integrating distributed renewable energy resources(DER)at multiple feed points.It examines the impact of incorporating renewable energy and evaluates system performance metrics such as robustness,static voltage stability,line carrying capacity,utility grid effectiveness,and losses within the conventional radial distribution framework commonly used in educational institutions.The contingency ranking of the real-time radial distribution system(RTRDS)for a typical educational institution consisting of N buses was conducted.Parameters such as the Voltage Performance Index(PIV)and Flow Performance Index(PIF)were evaluated.The results support the integration of distributed renewable energy sources within the existing radial distribution grid infrastructure.This research proposes enhanced contingency analyses through a straightforward reconfiguration process involving an additional tie line(Nþ1)for the existing N bus radial distribution system(RDS).Load flow analysis of the RDS with distributed renewable energy resources(DER)for both N bus and Nþ1 bus systems was conducted using the Gauss-Seidel and Newton–Raphson methods.Simulation results indicate that baseline loading is consistently maintained by grid sources and DER sources connected at multiple feed points.The proposed configuration of the Nþ1 bus system for the existing RTRDS was evaluated for voltage performance and compared with the Grey Wolf Optimization(GWO)algorithm.The results indicate that the Nþ1 bus configuration modeled using the MiPower tool performed comparably to the GWO results.Additionally,the contingency ranking for the proposed Nþ1 configuration was validated using the IEEE 10 and 30 bus system.展开更多
The increased level of penetration of wind generators into modern power system has significant effect on network operation. The time varying nature of wind speed has significant effect on performance of wind generator...The increased level of penetration of wind generators into modern power system has significant effect on network operation. The time varying nature of wind speed has significant effect on performance of wind generator, therefore efficient mechanism for stabilizing the output of the wind generator is very much needed. Self-excited induction generators （SEIG） already existing in the network are sensitive to wind speeds. In this paper, a new method for voltage control of SEIG utilizing reactive power enhancing capabilities of doubly-fed induction generator （DFIG） is simulated and its effect on the network is analyzed for varying wind speeds. The choice of placing DFIG adjacent to SEIG or at another bus is also addressed in this paper with simulation results. The results show that this method of utilizing the reactive power capabilities of DFIG enhances voltage stability of SEIG as well as system stability.展开更多
As power system interconnections become more prevalent, there has been an increase in use of thyristor controlled shunt connected compensation devices for dynamic power compensation and enhancement of real power trans...As power system interconnections become more prevalent, there has been an increase in use of thyristor controlled shunt connected compensation devices for dynamic power compensation and enhancement of real power transmission capacity. In this paper, an enhancement technique of real power transfer capacity of transmission lines is presented. A SVC （static var compensator） is designed and applied to a simple power system for this purpose. Increase in power flow and improvement in bus voltage profile are observed after using the SVC. Stability analysis of the system after experiencing fault as well as consequent fault clearance by time domain analysis has also beeu performed and satisfactory results are obtained.展开更多
文摘Load flow analysis is a significant tool for proper planning,operation,and dynamic analysis of a power system that provides the steady-state values of voltage magnitudes and angles at the fundamental frequency.However,due to the absence of a slack bus in an islanded microgrid,modified load flow algorithms should be adopted considering the system frequency as one of the solution variables.This paper proposes the application of nature-inspired hybrid optimization algorithms for solving the load flow problem of islanded microgrids.Several nature-inspired algorithms such as genetic algorithm(GA),differential evolution(DE),flower pollination algorithm(FPA),and grasshopper optimization algorithm(GOA)are separately merged with imperialistic competitive algorithm(ICA)to form four hybrid algorithms named as ICGA,ICDE,ICFPA,and ICGOA.Performances of these algorithms are tested on the 6-bus test system and the modified IEEE 37-bus test system.A comparison among the proposed algorithms is carried out in terms of statistical analysis conducted using SPSS statistics software.From the statistical analysis,it is identified that on an average,ICDE takes less number of iterations and consequently needs less execution time compared with other algorithms in solving the load flow problem of islanded microgrids.
文摘This research focuses on restructuring medium-level voltage(MLV)distribution systems by integrating distributed renewable energy resources(DER)at multiple feed points.It examines the impact of incorporating renewable energy and evaluates system performance metrics such as robustness,static voltage stability,line carrying capacity,utility grid effectiveness,and losses within the conventional radial distribution framework commonly used in educational institutions.The contingency ranking of the real-time radial distribution system(RTRDS)for a typical educational institution consisting of N buses was conducted.Parameters such as the Voltage Performance Index(PIV)and Flow Performance Index(PIF)were evaluated.The results support the integration of distributed renewable energy sources within the existing radial distribution grid infrastructure.This research proposes enhanced contingency analyses through a straightforward reconfiguration process involving an additional tie line(Nþ1)for the existing N bus radial distribution system(RDS).Load flow analysis of the RDS with distributed renewable energy resources(DER)for both N bus and Nþ1 bus systems was conducted using the Gauss-Seidel and Newton–Raphson methods.Simulation results indicate that baseline loading is consistently maintained by grid sources and DER sources connected at multiple feed points.The proposed configuration of the Nþ1 bus system for the existing RTRDS was evaluated for voltage performance and compared with the Grey Wolf Optimization(GWO)algorithm.The results indicate that the Nþ1 bus configuration modeled using the MiPower tool performed comparably to the GWO results.Additionally,the contingency ranking for the proposed Nþ1 configuration was validated using the IEEE 10 and 30 bus system.
文摘The increased level of penetration of wind generators into modern power system has significant effect on network operation. The time varying nature of wind speed has significant effect on performance of wind generator, therefore efficient mechanism for stabilizing the output of the wind generator is very much needed. Self-excited induction generators （SEIG） already existing in the network are sensitive to wind speeds. In this paper, a new method for voltage control of SEIG utilizing reactive power enhancing capabilities of doubly-fed induction generator （DFIG） is simulated and its effect on the network is analyzed for varying wind speeds. The choice of placing DFIG adjacent to SEIG or at another bus is also addressed in this paper with simulation results. The results show that this method of utilizing the reactive power capabilities of DFIG enhances voltage stability of SEIG as well as system stability.
文摘As power system interconnections become more prevalent, there has been an increase in use of thyristor controlled shunt connected compensation devices for dynamic power compensation and enhancement of real power transmission capacity. In this paper, an enhancement technique of real power transfer capacity of transmission lines is presented. A SVC （static var compensator） is designed and applied to a simple power system for this purpose. Increase in power flow and improvement in bus voltage profile are observed after using the SVC. Stability analysis of the system after experiencing fault as well as consequent fault clearance by time domain analysis has also beeu performed and satisfactory results are obtained.
