Photovoltaic power generating is one of the primary methods of utilizing solar energy resources,with large-scale photovoltaic grid-connected power generation being the most efficient way to fully utilize solar energy....Photovoltaic power generating is one of the primary methods of utilizing solar energy resources,with large-scale photovoltaic grid-connected power generation being the most efficient way to fully utilize solar energy.In order to provide reference strategies for pertinent researchers as well as potential implementation,this paper tries to provide a survey investigation and technical analysis of machine learning-related approaches,statistical approaches and optimization techniques for solar power generation and forecasting.Deep learning-related methods,in particular,can theoretically handle arbitrary nonlinear transformations through proper model structural design,such as hidden layer topology optimization and objective function analysis to save information that can increase forecasting accuracy while filtering out irrelevant or less affected data for forecasting.The research’s results indicate that RBFNN-AG performed the best when applying the predetermined number of days,with an NRMSE value of 4.65%.RBFNN-AG performs better than sophisticated models like DenseNet(5.69%),SLFN-ELM(5.95%),and ANN-k-means-linear regression correction(6.11%).Additionally,scenario application and PV system investment techniques are provided to evaluate the current condition of new energy development and market trends both domestically and internationally.展开更多
Fuel poverty is one of the global concerns affecting not only users’financial capacity or affordability for maintaining housing operation but also the occupants’health and wellbeing.Space heating and cooling require...Fuel poverty is one of the global concerns affecting not only users’financial capacity or affordability for maintaining housing operation but also the occupants’health and wellbeing.Space heating and cooling require a relatively large amount of domestic energy use in housing.Therefore,this study was formed with the aim to propose an innovative approach to utilising free,clean renewable sources of energy applicable to the space heating and cooling of housing in both cold and hot regions.Accordingly,housing test facilities based in Melbourne,Australia,and Kuching,Malaysia,were selected and used for this study that examined the thermal performance of a proposed‘hydronic radiator’(HR)system through simulation and onsite measurements.The geothermal heat capacity of a‘vertical ground heat exchanger’(VGHE)installed in the house in Melbourne was examined previously by the authors and the VGHE measured data was also applied to this HR performance simulation.The water that circulates through the HRs is heated by sunlight and VGHE or cooled by night sky radiation.This study drew conclusions that the sole utilisation of renewable sources through these proposed HR space heating and cooling systems can provide thermally accessible or comfortable indoor living environments in both heating or cooling dominant regions.Thus,fuel poverty issues may be alleviated through HR system application.The HRs can remove a‘sensible’portion of metabolic heat,but they cannot effectively contribute to the‘latent’heat removal.Thus,the future potential use or effect of‘flow-through’HRs,which are integrated into a underfloor air distribution(UFAD)plenum,was also dsicussed in this study.In the test house located in Melbourne,the flow-through HR UFAD system is currently under development.Therefore,the performance will be measured once the system has come into operation for further testing.展开更多
This paper proposes a simple and practical approach to model the uncertainty of solar irradiance and determines the optimized day-ahead(DA)schedule of electricity mar-ket.The problem formulation incorporates the power...This paper proposes a simple and practical approach to model the uncertainty of solar irradiance and determines the optimized day-ahead(DA)schedule of electricity mar-ket.The problem formulation incorporates the power output of distributed solar photovoltaic generator(DSPVG)and forecasted load demands with a specified level of certainty.The proposed approach determines the certainty levels of the random variables(solar irradiance and forecasted load demand)from their probability density function curves.In this process of optimization,the energy storage system(ESS)has also been mod-eled based on the fact that the energy stored during low locational marginal price(LMP)periods and dispatched during high LMP periods would strengthen the economy of DA schedule.The objective of the formulated non-linear optimization problem is to maximize the social welfare of market participants,which incorporates the assured generation outputs of DSPVG,subject to real and reactive power balance and transmission capability constraints of the system and charging/dis-charging and energy storage constraints of ESS.The simulation has been performed on the Indian utility 62-bus system.The results are presented with a large number of cases to demonstrate the effectiveness of the proposed approach for the efficient,economic and reliable operation of DA electricity markets.展开更多
The photovoltaic virtual synchronous generator(PV-VSG)solves the problem of lack of inertia in the PV power-generation system.The existing PV plants without energy storage are required to participate in the power grid...The photovoltaic virtual synchronous generator(PV-VSG)solves the problem of lack of inertia in the PV power-generation system.The existing PV plants without energy storage are required to participate in the power grid’s frequency modulation(FM),but existing PV-VSGs with energy storage have high requirements for coordinated control.Therefore,the active power reserve PV-VSG(APR-PV-VSG)is studied.Based on the different methods to obtain the maximum power point(MPP),the peer-to-peer and master-slave APR-PV-VSG strategies are proposed.The PV inverters are deviated from the MPP to reserve active power,which is used as the virtual inertia and primary FM power.These methods equip the PV power station with FM capability.The effectiveness of the proposed control strategies is verified by simulation results.展开更多
This paper proposes a power system concept that integrates photovoltaic (PV) and thermoelectric (TE) technologies to harvest solar energy from a wide spectral range. By introduction of the 'spectrum beam splittin...This paper proposes a power system concept that integrates photovoltaic (PV) and thermoelectric (TE) technologies to harvest solar energy from a wide spectral range. By introduction of the 'spectrum beam splitting' technique, short wavelength solar radiation is converted directly into electricity in the PV cells, while the long wavelength segment of the spectrum is used to produce moderate to high temperature thermal energy, which then generates electricity in the TE device. To overcome the intermittent nature of solar radiation, the system is also coupled to a thermal energy storage unit. A systematic analysis of the integrated system is carried out, encompassing the system configuration, material properties, thermal management, and energy storage aspects. We have also attempted to optimize the integrated system. The results indicate that the system configuration and optimization are the most important factors for high overall efficiency.展开更多
基金supported by the National Natural Science Foundation of China(NSFC)(Nos.61902158,61806087).
文摘Photovoltaic power generating is one of the primary methods of utilizing solar energy resources,with large-scale photovoltaic grid-connected power generation being the most efficient way to fully utilize solar energy.In order to provide reference strategies for pertinent researchers as well as potential implementation,this paper tries to provide a survey investigation and technical analysis of machine learning-related approaches,statistical approaches and optimization techniques for solar power generation and forecasting.Deep learning-related methods,in particular,can theoretically handle arbitrary nonlinear transformations through proper model structural design,such as hidden layer topology optimization and objective function analysis to save information that can increase forecasting accuracy while filtering out irrelevant or less affected data for forecasting.The research’s results indicate that RBFNN-AG performed the best when applying the predetermined number of days,with an NRMSE value of 4.65%.RBFNN-AG performs better than sophisticated models like DenseNet(5.69%),SLFN-ELM(5.95%),and ANN-k-means-linear regression correction(6.11%).Additionally,scenario application and PV system investment techniques are provided to evaluate the current condition of new energy development and market trends both domestically and internationally.
文摘Fuel poverty is one of the global concerns affecting not only users’financial capacity or affordability for maintaining housing operation but also the occupants’health and wellbeing.Space heating and cooling require a relatively large amount of domestic energy use in housing.Therefore,this study was formed with the aim to propose an innovative approach to utilising free,clean renewable sources of energy applicable to the space heating and cooling of housing in both cold and hot regions.Accordingly,housing test facilities based in Melbourne,Australia,and Kuching,Malaysia,were selected and used for this study that examined the thermal performance of a proposed‘hydronic radiator’(HR)system through simulation and onsite measurements.The geothermal heat capacity of a‘vertical ground heat exchanger’(VGHE)installed in the house in Melbourne was examined previously by the authors and the VGHE measured data was also applied to this HR performance simulation.The water that circulates through the HRs is heated by sunlight and VGHE or cooled by night sky radiation.This study drew conclusions that the sole utilisation of renewable sources through these proposed HR space heating and cooling systems can provide thermally accessible or comfortable indoor living environments in both heating or cooling dominant regions.Thus,fuel poverty issues may be alleviated through HR system application.The HRs can remove a‘sensible’portion of metabolic heat,but they cannot effectively contribute to the‘latent’heat removal.Thus,the future potential use or effect of‘flow-through’HRs,which are integrated into a underfloor air distribution(UFAD)plenum,was also dsicussed in this study.In the test house located in Melbourne,the flow-through HR UFAD system is currently under development.Therefore,the performance will be measured once the system has come into operation for further testing.
文摘This paper proposes a simple and practical approach to model the uncertainty of solar irradiance and determines the optimized day-ahead(DA)schedule of electricity mar-ket.The problem formulation incorporates the power output of distributed solar photovoltaic generator(DSPVG)and forecasted load demands with a specified level of certainty.The proposed approach determines the certainty levels of the random variables(solar irradiance and forecasted load demand)from their probability density function curves.In this process of optimization,the energy storage system(ESS)has also been mod-eled based on the fact that the energy stored during low locational marginal price(LMP)periods and dispatched during high LMP periods would strengthen the economy of DA schedule.The objective of the formulated non-linear optimization problem is to maximize the social welfare of market participants,which incorporates the assured generation outputs of DSPVG,subject to real and reactive power balance and transmission capability constraints of the system and charging/dis-charging and energy storage constraints of ESS.The simulation has been performed on the Indian utility 62-bus system.The results are presented with a large number of cases to demonstrate the effectiveness of the proposed approach for the efficient,economic and reliable operation of DA electricity markets.
基金Supported by the Joint Funds of the National Natural Science Foundation of China(U1766207).
文摘The photovoltaic virtual synchronous generator(PV-VSG)solves the problem of lack of inertia in the PV power-generation system.The existing PV plants without energy storage are required to participate in the power grid’s frequency modulation(FM),but existing PV-VSGs with energy storage have high requirements for coordinated control.Therefore,the active power reserve PV-VSG(APR-PV-VSG)is studied.Based on the different methods to obtain the maximum power point(MPP),the peer-to-peer and master-slave APR-PV-VSG strategies are proposed.The PV inverters are deviated from the MPP to reserve active power,which is used as the virtual inertia and primary FM power.These methods equip the PV power station with FM capability.The effectiveness of the proposed control strategies is verified by simulation results.
基金supported by the Focused Deployment Project of the Chinese Academy of Sciences(KGZD-EW-302-1)the Key Technologies R&D Program of China(grant no.2012BAA03B03)a UK EPSRC grant under EP/K002252/1
文摘This paper proposes a power system concept that integrates photovoltaic (PV) and thermoelectric (TE) technologies to harvest solar energy from a wide spectral range. By introduction of the 'spectrum beam splitting' technique, short wavelength solar radiation is converted directly into electricity in the PV cells, while the long wavelength segment of the spectrum is used to produce moderate to high temperature thermal energy, which then generates electricity in the TE device. To overcome the intermittent nature of solar radiation, the system is also coupled to a thermal energy storage unit. A systematic analysis of the integrated system is carried out, encompassing the system configuration, material properties, thermal management, and energy storage aspects. We have also attempted to optimize the integrated system. The results indicate that the system configuration and optimization are the most important factors for high overall efficiency.