The introduction of daylight can improve buildings’energy efficiency and bring benefit to occupant satisfaction.However,the introduction of daylight may accompany with excessive heat.Properly counterbalancing the ene...The introduction of daylight can improve buildings’energy efficiency and bring benefit to occupant satisfaction.However,the introduction of daylight may accompany with excessive heat.Properly counterbalancing the energy consumption of air conditioning and lighting systems owing to the entry of daylight is a critical control target of dynamic shading adjustment in cooling season.Most dynamic shading control strategies in use only consider one single system.Additionally,for advanced control mode like performance-based control,the predictive model usually only examines the instantaneous effect of energy performance to determine the shading adjustment state,unable to quantify the overall influence of shading adjustment state on building energy consumption.In order to address this issue,special consideration is given to calculating the cumulative contribution of heat gains to cooling load in this study.An overall energy-efficient shading control metric is proposed and used as basis to develop optimized dynamic shading control strategy.An application example demonstrates that the SGR-Optimal control strategy can further save energy by 21.8%~38.8%when compared to the Rule-based control strategy,thus allowing a better exploration of the energy efficiency potential of daylight measure.展开更多
Tracking the maximum power point is a critical issue with solar systems.The power output of the solar panel varies due to variations in irradiance and temperature.Nonuniform irradiation due to partial shading conditio...Tracking the maximum power point is a critical issue with solar systems.The power output of the solar panel varies due to variations in irradiance and temperature.Nonuniform irradiation due to partial shading conditions has a direct impact on the characteristics of photovoltaic(PV)systems.To build a diversity of maximum power point tracking algorithms in solar PV systems,this work focuses on perturb and observe,incremental conductance,and fuzzy logic control methodologies.The suggested fuzzy logic control method outperformed the conventional incremental conductance and perturb and observe algorithms with a collection of 49 rules.This paper presents a novel series-parallel-cross-tied PV array configuration with a developed fuzzy methodology.To comment on the performance of a proposed system under various partial shading conditions,a series-parallel PV array configuration has been considered.The simulation result demonstrates that the fuzzy method has a percentage improvement in the global maximum power point tracking efficiency of 24.85%when compared to the perturb and observe method and a 65.5%improvement when compared to the incremental conductance method under long wide partial shading conditions.In the case of the middle partial shading condition,the fuzzy method has a percentage improvement in the global maximum power point tracking efficiency of 12.4%compared to the perturb and observe method and a 60.7%improvement compared to the incremental conductance method.展开更多
文摘The introduction of daylight can improve buildings’energy efficiency and bring benefit to occupant satisfaction.However,the introduction of daylight may accompany with excessive heat.Properly counterbalancing the energy consumption of air conditioning and lighting systems owing to the entry of daylight is a critical control target of dynamic shading adjustment in cooling season.Most dynamic shading control strategies in use only consider one single system.Additionally,for advanced control mode like performance-based control,the predictive model usually only examines the instantaneous effect of energy performance to determine the shading adjustment state,unable to quantify the overall influence of shading adjustment state on building energy consumption.In order to address this issue,special consideration is given to calculating the cumulative contribution of heat gains to cooling load in this study.An overall energy-efficient shading control metric is proposed and used as basis to develop optimized dynamic shading control strategy.An application example demonstrates that the SGR-Optimal control strategy can further save energy by 21.8%~38.8%when compared to the Rule-based control strategy,thus allowing a better exploration of the energy efficiency potential of daylight measure.
文摘Tracking the maximum power point is a critical issue with solar systems.The power output of the solar panel varies due to variations in irradiance and temperature.Nonuniform irradiation due to partial shading conditions has a direct impact on the characteristics of photovoltaic(PV)systems.To build a diversity of maximum power point tracking algorithms in solar PV systems,this work focuses on perturb and observe,incremental conductance,and fuzzy logic control methodologies.The suggested fuzzy logic control method outperformed the conventional incremental conductance and perturb and observe algorithms with a collection of 49 rules.This paper presents a novel series-parallel-cross-tied PV array configuration with a developed fuzzy methodology.To comment on the performance of a proposed system under various partial shading conditions,a series-parallel PV array configuration has been considered.The simulation result demonstrates that the fuzzy method has a percentage improvement in the global maximum power point tracking efficiency of 24.85%when compared to the perturb and observe method and a 65.5%improvement when compared to the incremental conductance method under long wide partial shading conditions.In the case of the middle partial shading condition,the fuzzy method has a percentage improvement in the global maximum power point tracking efficiency of 12.4%compared to the perturb and observe method and a 60.7%improvement compared to the incremental conductance method.
