The paper makes survey of operating principle of power management of photovoltaic system with supercapacitors and a maximum power tracker （MPT） control to achieve the maximum efficiency. Supercapacitors are well sui...The paper makes survey of operating principle of power management of photovoltaic system with supercapacitors and a maximum power tracker （MPT） control to achieve the maximum efficiency. Supercapacitors are well suited to replace classical batteries and conventional capacitors in photovoltaic applications to improve a dynamic behaviors and life-time. It describes the advantages of a supercapacitors solution and shows the results of comparison with convenient batteries. The paper presents different topologies of basic photovoltaic concepts with dc-dc converters and supercapacitors according to the power dimension. The mathematical equations describing the photovoltaic cells, temperature analyses and mathematical solution of MPT are shown in the paper and supported by measurements. The mathematical models were applied in the design of 50 W and 6 kW photovoltaic sources with MPT and supercapacitors. Both models were verified using experimental measurements on the photovoltaic setup.展开更多
A single-phase modular multilevel inverter based photovoltaic system for grid connection is proposed. This photovoltaic system utilizes two conversion stages： a boost converter for tracking the maximum power point an...A single-phase modular multilevel inverter based photovoltaic system for grid connection is proposed. This photovoltaic system utilizes two conversion stages： a boost converter for tracking the maximum power point and a modular multilevel inverter used as an interfacing unit. The maximum power point tracking is achieved with a fuzzy logic controller, and the modular multilevel inverter regulates the DC link voltage and synchronizes the grid voltage and current in order to achieve unity power factor operation. The proposed system provides high dynamic performance and power quality injected into the grid. The validity of the proposed system is confirmed by simulations.展开更多
To extract the maximum power from a photovoltaic （PV） energy system, the real-time maximum power point （MPP） of the PV array must be tracked closely. The non-linear and time-variant characteristics of the PV array...To extract the maximum power from a photovoltaic （PV） energy system, the real-time maximum power point （MPP） of the PV array must be tracked closely. The non-linear and time-variant characteristics of the PV array and the non-linear and non-minimum phase characteristics of a boost converter make it difficult to track the MPP for traditional control strategies. We propose a fuzzy neural network controller （FNNC）, which combines the reasoning capability of fuzzy logical systems and the learning capability of neural networks, to track the MPP. With a derived learning algorithm, the parameters of the FNNC are updated adaptively. A gradient estimator based on a radial basis function neural network is developed to provide the reference information to the FNNC. Simulation results show that the proposed control algorithm provides much better tracking performance compared with the filzzy logic control algorithm.展开更多
文摘The paper makes survey of operating principle of power management of photovoltaic system with supercapacitors and a maximum power tracker （MPT） control to achieve the maximum efficiency. Supercapacitors are well suited to replace classical batteries and conventional capacitors in photovoltaic applications to improve a dynamic behaviors and life-time. It describes the advantages of a supercapacitors solution and shows the results of comparison with convenient batteries. The paper presents different topologies of basic photovoltaic concepts with dc-dc converters and supercapacitors according to the power dimension. The mathematical equations describing the photovoltaic cells, temperature analyses and mathematical solution of MPT are shown in the paper and supported by measurements. The mathematical models were applied in the design of 50 W and 6 kW photovoltaic sources with MPT and supercapacitors. Both models were verified using experimental measurements on the photovoltaic setup.
文摘A single-phase modular multilevel inverter based photovoltaic system for grid connection is proposed. This photovoltaic system utilizes two conversion stages： a boost converter for tracking the maximum power point and a modular multilevel inverter used as an interfacing unit. The maximum power point tracking is achieved with a fuzzy logic controller, and the modular multilevel inverter regulates the DC link voltage and synchronizes the grid voltage and current in order to achieve unity power factor operation. The proposed system provides high dynamic performance and power quality injected into the grid. The validity of the proposed system is confirmed by simulations.
基金Project (No. 20576071) supported by the National Natural Science Foundation of China
文摘To extract the maximum power from a photovoltaic （PV） energy system, the real-time maximum power point （MPP） of the PV array must be tracked closely. The non-linear and time-variant characteristics of the PV array and the non-linear and non-minimum phase characteristics of a boost converter make it difficult to track the MPP for traditional control strategies. We propose a fuzzy neural network controller （FNNC）, which combines the reasoning capability of fuzzy logical systems and the learning capability of neural networks, to track the MPP. With a derived learning algorithm, the parameters of the FNNC are updated adaptively. A gradient estimator based on a radial basis function neural network is developed to provide the reference information to the FNNC. Simulation results show that the proposed control algorithm provides much better tracking performance compared with the filzzy logic control algorithm.
