Most of the photo voltaic (PV) arrays often work in harsh outdoor environment, and undergo various faults, such as local material aging, shading, open circuit, short circuit and so on. The generation of these faults w...Most of the photo voltaic (PV) arrays often work in harsh outdoor environment, and undergo various faults, such as local material aging, shading, open circuit, short circuit and so on. The generation of these faults will reduce the power generation efficiency, and when a fault occurs in a PV model, the PV model and the systems connected to it are also damaged. In this paper, an on-line distributed monitoring system based on XBee wireless sensors network is designed to monitor the output current, voltage and irradiation of each PV module, and the temperature and the irradiation of the environment. A simulation PV module model is established, based on which some common faults are simulated and fault training samples are obtained. Finally, a memetic algorithm optimized Back Propagation ANN fault diagnosis model is built and trained by the fault samples data. Experiment result shows that the system can detect the common faults of PV array with high accuracy.展开更多
In this paper a fuzzy logic （FL） based model reference adaptive system （MRAS） speed observer for high performance AC drives is proposed. The error vector computation is made based on the rotor-flux derived from th...In this paper a fuzzy logic （FL） based model reference adaptive system （MRAS） speed observer for high performance AC drives is proposed. The error vector computation is made based on the rotor-flux derived from the reference and the adaptive model of the induction motor. The error signal is processed in the proposed fuzzy logic controller （FLC） for speed adaptation. The drive employs an indirect vector control scheme for achieving a good closed loop speed control. For powering the drive system, a standalone photovoltaic （PV） energy source is used. To extract the maximum power from the PV source, a constant voltage controller （CVC） is also proposed. The complete drive system is modeled in MATLAB/Simulink and the performance is analyzed for different operating conditions.展开更多
Solar photovoltaic(PV)systems have gained importance as a promising renewable energy source in recent years.PV arrays are prone to variable irradiance levels under partial shading conditions due to non-uniform shading...Solar photovoltaic(PV)systems have gained importance as a promising renewable energy source in recent years.PV arrays are prone to variable irradiance levels under partial shading conditions due to non-uniform shading.As a result,there will be a decrease in the amount of power produced and hotspots will occur.To overcome these issues,it is essential to select an appropriate PV material and a suitable array configuration.To obtain the maximum output power from a PV array under partial shading conditions,this paper suggests a novel triple-series–parallel ladder topology with monocrystalline PV material.Considering short and wide,long and wide,short and narrow,long and narrow,middle and diagonal shading situations,a 6×6-sized array has been considered and compared with other existing configurations such as total cross-tied,bridge-link,honeycomb,series–parallel and series–parallel cross-tied.The proposed configuration has an optimal number of cross ties to produce maximum power.It has 4 cross ties fewer than a honeycomb,3 cross ties fewer than a bridge link,16 cross ties fewer than a total cross-tied and 7 cross ties fewer than series–parallel cross-tied configurations.The proposed configuration has an improvement in power of 0.1%to 20%compared with other configurations under the considered shading scenarios.展开更多
The grid-connected or standalone PV central inverter architecture is comprised of several PV modules which are connected in different ways to form the PV array.The power generation capability of the PV array is primar...The grid-connected or standalone PV central inverter architecture is comprised of several PV modules which are connected in different ways to form the PV array.The power generation capability of the PV array is primarily affected by partial shading conditions(PSC).Due to PSCs,the power output of the PV array is dramatically reduced,and mismatching losses are induced in the PV modules.Based on the extent of these problems,multiple peaks also appear in the power-voltage(P-V)curve,which makes it very difficult to track the global maximum power point(GMPP).The main objective of this research paper is to model and simulate the series(S),series-parallel(SP),bridge-link(BL),honey-comb(HC),total-cross-tied(TCT)and proposed triple-tied(TT)solar PV array configurations under various partial shading scenarios.The performance of all PV configurations is evaluated under a uniform approach,considering eight different shading scenarios.The performance of the considered PV configurations is analyzed in terms of their mismatching power losses,fill factors,efficiency,global maximum power points(GMPPs),local maximum power points(LMPPs),voltages and currents at GMPPs,open circuit voltage and short circuit currents.The above-mentioned PV configurations are modeled and simulated in a Matlab/Simulink environment by considering the KC-200GT module parameters.展开更多
文摘Most of the photo voltaic (PV) arrays often work in harsh outdoor environment, and undergo various faults, such as local material aging, shading, open circuit, short circuit and so on. The generation of these faults will reduce the power generation efficiency, and when a fault occurs in a PV model, the PV model and the systems connected to it are also damaged. In this paper, an on-line distributed monitoring system based on XBee wireless sensors network is designed to monitor the output current, voltage and irradiation of each PV module, and the temperature and the irradiation of the environment. A simulation PV module model is established, based on which some common faults are simulated and fault training samples are obtained. Finally, a memetic algorithm optimized Back Propagation ANN fault diagnosis model is built and trained by the fault samples data. Experiment result shows that the system can detect the common faults of PV array with high accuracy.
文摘In this paper a fuzzy logic （FL） based model reference adaptive system （MRAS） speed observer for high performance AC drives is proposed. The error vector computation is made based on the rotor-flux derived from the reference and the adaptive model of the induction motor. The error signal is processed in the proposed fuzzy logic controller （FLC） for speed adaptation. The drive employs an indirect vector control scheme for achieving a good closed loop speed control. For powering the drive system, a standalone photovoltaic （PV） energy source is used. To extract the maximum power from the PV source, a constant voltage controller （CVC） is also proposed. The complete drive system is modeled in MATLAB/Simulink and the performance is analyzed for different operating conditions.
文摘Solar photovoltaic(PV)systems have gained importance as a promising renewable energy source in recent years.PV arrays are prone to variable irradiance levels under partial shading conditions due to non-uniform shading.As a result,there will be a decrease in the amount of power produced and hotspots will occur.To overcome these issues,it is essential to select an appropriate PV material and a suitable array configuration.To obtain the maximum output power from a PV array under partial shading conditions,this paper suggests a novel triple-series–parallel ladder topology with monocrystalline PV material.Considering short and wide,long and wide,short and narrow,long and narrow,middle and diagonal shading situations,a 6×6-sized array has been considered and compared with other existing configurations such as total cross-tied,bridge-link,honeycomb,series–parallel and series–parallel cross-tied.The proposed configuration has an optimal number of cross ties to produce maximum power.It has 4 cross ties fewer than a honeycomb,3 cross ties fewer than a bridge link,16 cross ties fewer than a total cross-tied and 7 cross ties fewer than series–parallel cross-tied configurations.The proposed configuration has an improvement in power of 0.1%to 20%compared with other configurations under the considered shading scenarios.
基金This work was supported by the Science and Engineering Research Board(SERB),Department of Science and Technology,Government of India under the Grant No:ECR/2017/000316。
文摘The grid-connected or standalone PV central inverter architecture is comprised of several PV modules which are connected in different ways to form the PV array.The power generation capability of the PV array is primarily affected by partial shading conditions(PSC).Due to PSCs,the power output of the PV array is dramatically reduced,and mismatching losses are induced in the PV modules.Based on the extent of these problems,multiple peaks also appear in the power-voltage(P-V)curve,which makes it very difficult to track the global maximum power point(GMPP).The main objective of this research paper is to model and simulate the series(S),series-parallel(SP),bridge-link(BL),honey-comb(HC),total-cross-tied(TCT)and proposed triple-tied(TT)solar PV array configurations under various partial shading scenarios.The performance of all PV configurations is evaluated under a uniform approach,considering eight different shading scenarios.The performance of the considered PV configurations is analyzed in terms of their mismatching power losses,fill factors,efficiency,global maximum power points(GMPPs),local maximum power points(LMPPs),voltages and currents at GMPPs,open circuit voltage and short circuit currents.The above-mentioned PV configurations are modeled and simulated in a Matlab/Simulink environment by considering the KC-200GT module parameters.
