This paper presents an application of GRADE Algorithm based approach along with PV analysis to solve multi objective optimization problem of minimizing real power losses, improving the voltage profile and hence enhanc...This paper presents an application of GRADE Algorithm based approach along with PV analysis to solve multi objective optimization problem of minimizing real power losses, improving the voltage profile and hence enhancing the performance of power system. GRADE Algorithm is a hybrid technique combining genetic and differential evolution algorithms. Control variables considered are Generator bus voltages, MVAR at capacitor banks, transformer tap settings and reactive power generation at generator buses. The optimal values of the control variables are obtained by solving the multi objective optimization problem using GRADE Algorithm programmed using M coding in MATLAB platform. With the optimal setting for the control variables, Newton Raphson based power flow is performed for two test systems, viz, IEEE 30 bus system and IEEE 57 bus system for three loading conditions. Minimization of Real power loss and improvement of voltage profile obtained are compared with the results obtained using firefly and particle swarm optimization (PSO) techniques. Improvement of Loadability margin is established through PV curve plotted using continuation power flow with the real power load at the most affected bus as the bifurcation parameter. The simulated output shows improved results when compared to that of firefly and PSO techniques, in term of convergence time, reduction of real power loss, improvement of voltage profile and enhancement of loadability margin.展开更多
Discusses the significance of induction motor constant resistance (IM R) load on the lower part of the PV curve of a power system and determines the conditions for stable operation of IM R load using fuzzy techniques ...Discusses the significance of induction motor constant resistance (IM R) load on the lower part of the PV curve of a power system and determines the conditions for stable operation of IM R load using fuzzy techniques and load flow.展开更多
The static voltage stability of the power system integrating wind farms adopting different kinds of wind turbines is analyzed. Through the simulation of one certain local power grid in Xinjiang Uygur Autonomous Region...The static voltage stability of the power system integrating wind farms adopting different kinds of wind turbines is analyzed. Through the simulation of one certain local power grid in Xinjiang Uygur Autonomous Region, the PV curves at the point of common coupling (PCC), key buses and important substations are plotted; the variation of voltage as well as the limit and margin of static stability are analyzed. It is resulted from the simulation that the limit of static voltage at weak nodes is lower, and the static voltage of the power system with wind farms adopting doubly-fed induction generators (DFIG) is more stable than that with wind farms adopting common asynchronous generators.展开更多
Building integrated photovoltaic(BIPV)windows impact building performance by balancing daylighting availability,visual comfort,solar power generation,and building energy consumption.Optimizing this balance is crucial ...Building integrated photovoltaic(BIPV)windows impact building performance by balancing daylighting availability,visual comfort,solar power generation,and building energy consumption.Optimizing this balance is crucial for improving overall building energy efficiency and indoor environment quality.This study introduces a novel curved photovoltaic window design aimed at increasing daylight transmittance while maintaining the same photovoltaic area as a flat PV window.The annual daylighting availability,visual comfort and building energy performance of three types of flat/curved PV windows(180°,120°,0°-flat)in a reference office room was comparatively studied across five different climate zones in China(Xiamen,Harbin,Nanjing,Kunming,and Beijing).The PV model was validated by the experimental data.The results showed that the room with curved PV windows had significantly higher daylighting availability compared to flat windows,with the growth rates of the spatial useful daylight illuminance ranging of 3.94%–4.78%and 5.56%–5.94%,respectively,for the curved PV windows at central angles of 120°and 180°across different climate zones.The 120°curved PV windows achieved the lowest net energy used intensity(Net_EUI),suggesting the advantages of curved PV windows and proposed the existence of an optimal curvature for achieving the lowest Net_EUI.展开更多
Price decrease of photovoltaic(PV)energy in recent years allows to an increase in the use of small-scale PV modules,especially in the residential sector.Considering that houses and buildings are exposed to solar radia...Price decrease of photovoltaic(PV)energy in recent years allows to an increase in the use of small-scale PV modules,especially in the residential sector.Considering that houses and buildings are exposed to solar radiation during the day,it is possible to generate electricity by installing PV modules at strategic locations within the construction,using facades,windows,walls and roofs as Building Integrated Photovoltaic(BIPV)applications.Based on the above,it is analyzed the geometry of Colombian terraces corresponding to an area located on top of houses and buildings,which have flat open spaces that serve as roofs.Uses of terraces are related to drying clothes and cultivation;therefore,it is possible assign a portion of the entire area to the generation of electricity from the installation of PV modules.Occupation area due to integrated BIPV applications,is an important issue and is often limited to the flat geometry of most commercial solar panels.Thus,the goal of this work,is to generate curved photovoltaic surfaces that maximize the area exposed to the sun,seeking to increase the power of radiation captured and using the same area of occupation of conventional PV modules.To achieve this,a Genetic Algorithm(GA)is integrated into a computational ray tracing tool,in order to evaluate the radiation captured by a set of surfaces,which have a projected flat area on the terrace of 1m^(2),considering historical irradiance data in Medellín,Colombia.The optimal PV surface obtained,presents an additional 19.3%of captured energy and an additional area of 28%compared to the flat geometry.This is a promising finding because it shows a direct relationship between radiation capture and the geometric shape of the PV surface.The performance of the Optimal PV surface is validated and compared with flat geometry using TracePro.展开更多
文摘This paper presents an application of GRADE Algorithm based approach along with PV analysis to solve multi objective optimization problem of minimizing real power losses, improving the voltage profile and hence enhancing the performance of power system. GRADE Algorithm is a hybrid technique combining genetic and differential evolution algorithms. Control variables considered are Generator bus voltages, MVAR at capacitor banks, transformer tap settings and reactive power generation at generator buses. The optimal values of the control variables are obtained by solving the multi objective optimization problem using GRADE Algorithm programmed using M coding in MATLAB platform. With the optimal setting for the control variables, Newton Raphson based power flow is performed for two test systems, viz, IEEE 30 bus system and IEEE 57 bus system for three loading conditions. Minimization of Real power loss and improvement of voltage profile obtained are compared with the results obtained using firefly and particle swarm optimization (PSO) techniques. Improvement of Loadability margin is established through PV curve plotted using continuation power flow with the real power load at the most affected bus as the bifurcation parameter. The simulated output shows improved results when compared to that of firefly and PSO techniques, in term of convergence time, reduction of real power loss, improvement of voltage profile and enhancement of loadability margin.
文摘Discusses the significance of induction motor constant resistance (IM R) load on the lower part of the PV curve of a power system and determines the conditions for stable operation of IM R load using fuzzy techniques and load flow.
基金National Natural Science Foundation of China(5076700350867004)Autonomous university research projects(XJEDU2007105)
文摘The static voltage stability of the power system integrating wind farms adopting different kinds of wind turbines is analyzed. Through the simulation of one certain local power grid in Xinjiang Uygur Autonomous Region, the PV curves at the point of common coupling (PCC), key buses and important substations are plotted; the variation of voltage as well as the limit and margin of static stability are analyzed. It is resulted from the simulation that the limit of static voltage at weak nodes is lower, and the static voltage of the power system with wind farms adopting doubly-fed induction generators (DFIG) is more stable than that with wind farms adopting common asynchronous generators.
基金supported by the National Natural Science Foundation of China(No.52108098,No.52078443 and No.52308120)the Fundamental Research Funds for the Central Universities(No.20720220115 and No.20720240072)XMU Training Program of Innovation and Entrepreneurship for Undergraduates(No.S202410384553).
文摘Building integrated photovoltaic(BIPV)windows impact building performance by balancing daylighting availability,visual comfort,solar power generation,and building energy consumption.Optimizing this balance is crucial for improving overall building energy efficiency and indoor environment quality.This study introduces a novel curved photovoltaic window design aimed at increasing daylight transmittance while maintaining the same photovoltaic area as a flat PV window.The annual daylighting availability,visual comfort and building energy performance of three types of flat/curved PV windows(180°,120°,0°-flat)in a reference office room was comparatively studied across five different climate zones in China(Xiamen,Harbin,Nanjing,Kunming,and Beijing).The PV model was validated by the experimental data.The results showed that the room with curved PV windows had significantly higher daylighting availability compared to flat windows,with the growth rates of the spatial useful daylight illuminance ranging of 3.94%–4.78%and 5.56%–5.94%,respectively,for the curved PV windows at central angles of 120°and 180°across different climate zones.The 120°curved PV windows achieved the lowest net energy used intensity(Net_EUI),suggesting the advantages of curved PV windows and proposed the existence of an optimal curvature for achieving the lowest Net_EUI.
基金the framework of the ENERGETICA 2030 ResearchProgram,with code 58667 in the Colombia Cientfica initiative,funded by TheWorld Bank through the call 778-2017 Scientific Ecosystems,managed by the Colombian Ministry of Science,Technology and Innovation(Minciencias),with contract No.FP44842-210-2018。
文摘Price decrease of photovoltaic(PV)energy in recent years allows to an increase in the use of small-scale PV modules,especially in the residential sector.Considering that houses and buildings are exposed to solar radiation during the day,it is possible to generate electricity by installing PV modules at strategic locations within the construction,using facades,windows,walls and roofs as Building Integrated Photovoltaic(BIPV)applications.Based on the above,it is analyzed the geometry of Colombian terraces corresponding to an area located on top of houses and buildings,which have flat open spaces that serve as roofs.Uses of terraces are related to drying clothes and cultivation;therefore,it is possible assign a portion of the entire area to the generation of electricity from the installation of PV modules.Occupation area due to integrated BIPV applications,is an important issue and is often limited to the flat geometry of most commercial solar panels.Thus,the goal of this work,is to generate curved photovoltaic surfaces that maximize the area exposed to the sun,seeking to increase the power of radiation captured and using the same area of occupation of conventional PV modules.To achieve this,a Genetic Algorithm(GA)is integrated into a computational ray tracing tool,in order to evaluate the radiation captured by a set of surfaces,which have a projected flat area on the terrace of 1m^(2),considering historical irradiance data in Medellín,Colombia.The optimal PV surface obtained,presents an additional 19.3%of captured energy and an additional area of 28%compared to the flat geometry.This is a promising finding because it shows a direct relationship between radiation capture and the geometric shape of the PV surface.The performance of the Optimal PV surface is validated and compared with flat geometry using TracePro.
