A novel maximum power-point tracking approach is proposed based on studies investigating the output characteristics of photovoltaic(PV)systems under partial shading conditions.The existence of partially shaded conditi...A novel maximum power-point tracking approach is proposed based on studies investigating the output characteristics of photovoltaic(PV)systems under partial shading conditions.The existence of partially shaded conditions leads to the presence of several peaks on PV curves,which decrease the efficiency of conventional techniques.Hence,the proposed algorithm,which is based on the modified particle-swarm optimization(MPSO)technique,increases the output power of PV systems under such abnormal conditions and has a better performance compared to other methods.The proposed method is examined under several scenarios for partial shading condition and non-uniform irradiation levels using Matlab,and to investigate its effectiveness adequately,the results of the proposed method are compared with those of the neural network technique.The experimental results show that the proposed method can decrease the interference of the local maximum power-point to cause the PV system to operate at a global maximum power-point.The efficiency of the MPSO is achieved with the least number of steady-state oscillations under partial shading conditions compared with the neural network method.展开更多
In recent years,voltage stability issues have become a serious concern with regard to the safety of electrical systems,these issues are more evident and have wider consequences in vertical networks with an insufficien...In recent years,voltage stability issues have become a serious concern with regard to the safety of electrical systems,these issues are more evident and have wider consequences in vertical networks with an insufficient reactive power reserve.Pakistan is currently suffering from the worst energy crisis in its history.Owing to an increase in energy demand,the current transmission system is becoming increasingly inadequate.It has thus become necessary to reduce losses and enhance the system voltage profile for more efficient energy utilization.In this study,the main emphasis is on assessing the feasibility of using flexible AC transmission system devices and distributed generation to compensate power failures on the power lines of the Pakistani power transmission system.The load flow and contingency analyses are performed on a 132 kV transmission system that feeds power to the Quetta electric supply company.The region of Baluchistan is studied to evaluate the effectiveness of the proposed method.The system is simulated using NEPLAN,which accurately models the details of all system elements and the optimal power flow.The simulation results indicate that the proposed method helps reduce system losses,voltage deviation,and power flow congestion,with all system constraints within permissible limits.展开更多
基金Supported by the Hubei Provincial Natural Science Foundation of China(2015CFA010)the Technology Project of State Grid Company“Soft Connection Mechanism and Modeling of Smart Grid Adapting to the Development of Global Energy Interconnection”the 111 Projects(B17040).
文摘A novel maximum power-point tracking approach is proposed based on studies investigating the output characteristics of photovoltaic(PV)systems under partial shading conditions.The existence of partially shaded conditions leads to the presence of several peaks on PV curves,which decrease the efficiency of conventional techniques.Hence,the proposed algorithm,which is based on the modified particle-swarm optimization(MPSO)technique,increases the output power of PV systems under such abnormal conditions and has a better performance compared to other methods.The proposed method is examined under several scenarios for partial shading condition and non-uniform irradiation levels using Matlab,and to investigate its effectiveness adequately,the results of the proposed method are compared with those of the neural network technique.The experimental results show that the proposed method can decrease the interference of the local maximum power-point to cause the PV system to operate at a global maximum power-point.The efficiency of the MPSO is achieved with the least number of steady-state oscillations under partial shading conditions compared with the neural network method.
基金Supported by the International Cooperation Project(1402/250000909).
文摘In recent years,voltage stability issues have become a serious concern with regard to the safety of electrical systems,these issues are more evident and have wider consequences in vertical networks with an insufficient reactive power reserve.Pakistan is currently suffering from the worst energy crisis in its history.Owing to an increase in energy demand,the current transmission system is becoming increasingly inadequate.It has thus become necessary to reduce losses and enhance the system voltage profile for more efficient energy utilization.In this study,the main emphasis is on assessing the feasibility of using flexible AC transmission system devices and distributed generation to compensate power failures on the power lines of the Pakistani power transmission system.The load flow and contingency analyses are performed on a 132 kV transmission system that feeds power to the Quetta electric supply company.The region of Baluchistan is studied to evaluate the effectiveness of the proposed method.The system is simulated using NEPLAN,which accurately models the details of all system elements and the optimal power flow.The simulation results indicate that the proposed method helps reduce system losses,voltage deviation,and power flow congestion,with all system constraints within permissible limits.
