- 标题
- 摘要
- 关键词
- 实验方案
- 产品
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Fixed frequency integral sliding-mode current-controlled MPPT boost converter for two-stage PV generation system
摘要： In two-stage grid-integrated photovoltaic (PV) system, usually a DC–DC converter is employed between the PV modules and the inverter. The dynamic interactions between the DC–DC converter, inverter, and the maximum power point tracking (MPPT) controller may affect the system performances. This study gives an integral procedure to design a stable sliding-mode controller (SMC) based on fixed frequency equivalent control approach to improve the transient response of PV system and to track the reference voltage supplied by the voltage-oriented MPPT controller in the presence of environmental and load perturbations and converter output sinusoidal perturbations imposed by the second harmonic of the grid frequency. The controller consists of fast current tracking inner current loop based on SMC law whose sliding surface is defined by the input capacitor and inductor current and outer PI controller maintains required PV voltage regulation. The superiority of the controller is validated at different operating conditions through PSIM software and its performance is compared with variable frequency hysteresis-based SMC. To check the static and transient performances of the system, various experiments are conducted. The results obtained show very fast transient response in settling time and alleviation of chattering magnitude at various operating conditions.
关键词： maximum power point tracking (MPPT),DC–DC converter,transient response,PSIM software,settling time,chattering magnitude,voltage regulation,photovoltaic (PV) system,fixed frequency,sliding-mode controller (SMC),hysteresis-based SMC
更新于2025-09-19 17:13:59
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[IEEE 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - Chicago, IL, USA (2019.6.16-2019.6.21)] 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - Thinking Beyond Limiting Efficiencies Of Advanced Concepts: Design Rules And Material Requirements For Realistic Devices
摘要： The current-fed dual active bridge (CF-DAB) dc–dc converter gains growing applications in photovoltaic (PV) and energy storage systems due to its advantages, e.g., a wide input voltage range, a high step-up ratio, a low input current ripple, and a multiport interface capability. In addition, the direct input current controllability and extra control freedom of the CF-DAB converter make it possible to buffer the double-line-frequency energy in grid-interactive PV systems without using electrolytic capacitors in the dc link. Therefore, a PV system achieves high reliability and highly ef?cient maximum power point tracking. This paper studies the optimized operation of a CF-DAB converter for a PV application in order to improve the system ef?ciency. The operating principle and soft-switching conditions over the wide operating range are thoroughly analyzed with phase-shift control and duty-cycle control, and an optimized operating mode is proposed to achieve the minimum root-mean-square transformer current. The proposed operating mode can extend the soft-switching region and reduce the power loss, particularly under a heavy load and a high input voltage. Moreover, the ef?ciency can be further improved with a higher dc-link voltage. A 5-kW hardware prototype was built in the laboratory, and experimental results are provided for veri?cation. This paper provides a design guideline for the CF-DAB converter applied to PV systems, as well as other applications with a wide input voltage variation.
关键词： root-mean-square (RMS) current,photovoltaic (PV),soft switching,optimized operation,Current-fed dual active bridge (CF-DAB)
更新于2025-09-19 17:13:59
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Automatic detection of photovoltaic module defects in infrared images with isolated and develop-model transfer deep learning
摘要： With the rising use of photovoltaic and ongoing installation of large-scale photovoltaic systems worldwide, the automation of photovoltaic monitoring methods becomes important, as manual/visual inspection has limited applications. This research work deals with automatic detection of photovoltaic module defects in Infrared images with isolated deep learning and develop-model transfer deep learning techniques. An Infrared images dataset containing infrared images of normal operating and defective modules is collected and used to train the networks. The dataset is obtained from Infrared imaging performed on normal operating and defective photovoltaic modules with lab induced defects. An isolated learned model is trained from scratch using a light convolutional neural network design that achieved an average accuracy of 98.67%. For transfer learning, a base model is first developed (pre-trained) from electroluminescence images dataset of photovoltaic cells and then fine-tuned on infrared images dataset, that achieved an average accuracy of 99.23%. Both frameworks require low computation power and less time; and can be implemented with ordinary hardware. They also maintained real time prediction speed. The comparison shows that the develop-model transfer learning technique can help to improve the performance. In addition, we reviewed different kind of defects detectable from infrared imaging of photovoltaic modules, that can help in manual labelling for identifying different defect categories upon access to new huge data in future studies. Last of all, the presented frameworks are applied for experimental testing and qualitative evaluation.
关键词： Isolated deep learning,Develop-model transfer deep learning,Automatic defect detection,Thermography,Infrared images,Photovoltaic (PV) modules
更新于2025-09-19 17:13:59
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Photovoltaic Module Reliability || Qualification Testing
摘要： Chapter 3 described the types of accelerated stress tests that are typically applied to photovoltaic (PV) modules. These tests are used in research to evaluate how well modules perform in relation to the specific stresses applied during these tests. However, what the industry needs is a defined set of accelerated stress tests that can be applied to all modules in the same way. Such a set of tests are called Qualification Tests or often in Europe are referred to as Type Approval Testing. Qualification tests are a set of well‐defined accelerated stress tests developed out of a reliability program. They incorporate strict pass/fail criteria. Hoffman and Ross [1] defined the purpose of qualification testing as a means of rapidly detecting the presence of known failure or degradation modes in the intended environment(s). The stress levels and durations are limited so the tests can be completed within a reasonable amount of time and cost. One of the goals of Qualification testing is for a significant number of commercial module types to pass and that all subsequent production modules will be built the same way as the modules that were tested. Passing the Qualification test says the product meets the specific set of criteria, but doesn’t predict product lifetime nor indicate which product will last longer or which will degrade in operation. However, if properly designed, the Qualification test will be a good indicator that modules passing the test sequence will not suffer from infant mortality – that is they will survive for a reasonable amount of time in the field. The real usefulness of such a Qualification test sequence can only be validated by assessing the field performance of products that have successfully passed the test sequence.
关键词： failure or degradation modes,reliability program,pass/fail criteria,photovoltaic (PV) modules,Type Approval Testing,field performance,Qualification Tests,infant mortality
更新于2025-09-19 17:13:59
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[IEEE 2019 Innovations in Power and Advanced Computing Technologies (i-PACT) - Vellore, India (2019.3.22-2019.3.23)] 2019 Innovations in Power and Advanced Computing Technologies (i-PACT) - Single-Stage Multifunction Multilevel Converter for Grid Interactive Photovoltaic System using Cascaded Two-level Inverter
摘要： This paper presents a single-stage multilevel converter for grid interactive Photovoltaic (PV) system using a Cascaded Two-Level Inverter (CTLI). The converter uses less number of switches, less isolated DC sources and no extra components like capacitors and diodes which are used in conventional multilevel inverters (MLIs). The CTLI based grid tied Photovoltaic system tracks the maximum power produced by the PV array under varying insolation conditions and injects the active power into the grid. Additionally, the PV system is able to perform the reactive power compensation along with harmonics elimination for nonlinear load within the capacity of inverter. These multi-functionality increases overall utilization of the system. The control scheme of the CTLI based grid interactive PV system is developed using instantaneous power (p-q) theory. The control of CTLI based multifunctional grid interactive PV system is verified through MATLAB/Simulink simulations. The simulation results validate the performance of CTLI based grid tied PV system for MPPT as well as active and reactive power control for changing insolation and load conditions.
关键词： Cascaded Two-Level Inverter (CTLI),Maximum Power Point Tracking (MPPT),Photovoltaic (PV),Multilevel Inverter (MLI)
更新于2025-09-19 17:13:59
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CNN based automatic detection of photovoltaic cell defects in electroluminescence images
摘要： Automatic defect detection is gaining huge importance in photovoltaic (PV) field due to limited application of manual/visual inspection and rising production quantities of PV modules. This study is conducted for automatic detection of PV module defects in electroluminescence (EL) images. We presented a novel approach using light convolutional neural network architecture for recognizing defects in EL images which achieves state of the art results of 93.02 % on solar cell dataset of EL images. It requires less computational power and time. It can work on an ordinary CPU computer while maintaining real time speed. It takes only 8.07 milliseconds for predicting one image. For proposing light architecture, we perform extensive experimentation on series of architectures. Moreover, we evaluate data augmentation operations to deal with data scarcity. Overfitting appears a significant problem; thus, we adopt appropriate strategies to generalize model. The impact of each strategy is presented. In addition, cracking patterns and defects that can appear in EL images are reviewed; which will help to label new images appropriately for predicting specific defect types upon availability of large data. The proposed framework is experimentally applied in lab and can help for automatic defect detection in field and industry.
关键词： PV cell cracking,Automatic defect detection,Convolutional neural network (CNN),Electroluminescence,Deep learning,Photovoltaic (PV) modules
更新于2025-09-19 17:13:59
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[IEEE 2019 Eleventh International Conference on Ubiquitous and Future Networks (ICUFN) - Zagreb, Croatia (2019.7.2-2019.7.5)] 2019 Eleventh International Conference on Ubiquitous and Future Networks (ICUFN) - Implement of 100-Gbps optical transceiver firmware for optical communication systems
摘要： This paper proposes a new fast technique, in which the slope of a photovoltaic (PV) inverter current is utilized to predict if the current is expected to exceed its rated value due to any grid faults. Two applications of this technique are demonstrated. In jurisdictions where grid codes require distributed generators (DGs) to disconnect after a fault occurrence, such as in Ontario, Canada, this technique is utilized to rapidly disconnect the PV solar system even before the inverter short circuit current actually exceeds the rated current of the inverter, thereby obviating the problem of any adverse short circuit current contribution into the grid. However, in regions where grid codes require DGs to stay connected and provide grid support, such as low-voltage ride through, this technique can be used to rapidly and autonomously transform the PV solar farm into a dynamic reactive power compensator STATCOM (termed PV-STATCOM) for providing voltage support function. In this paper, the PV-STATCOM is used to stabilize a critical induction motor load in the vicinity of the solar farm, which would have otherwise become unstable due to the grid fault. PSCAD-based simulation studies are performed on a realistic distribution network to demonstrate the effectiveness of this technique.
关键词： STATCOM,Distributed generator (DG),inverter,flexible AC transmission system (FACTS),protection,short circuit current,PV-STATCOM,photovoltaic (PV) systems
更新于2025-09-19 17:13:59
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[IEEE 2019 International Conference on Advanced Systems and Emergent Technologies (IC_ASET) - Hammamet, Tunisia (2019.3.19-2019.3.22)] 2019 International Conference on Advanced Systems and Emergent Technologies (IC_ASET) - MPPT Control of a Photovoltaic System based on Sliding Mode Control
摘要： In this paper, we introduce a PV system consisting of a photovoltaic panel and a boost converter. The output of photovoltaic systems is not fixed. It varies according to the temperature of the solar cells and the solar radiation. Generally, the temperature and solar radiation is not constant and thus affects the output of our panel. Furthermore, we proposed a sliding mode control for our chopper, which will leads to the maximum power point tracking (MPPT). Therefore, we performed simulation tests under different environmental conditions and discussed the results to confirm that slip control was effective to the Perturb and Observe (P&O) method.
关键词： sliding Control,P&O,boost converter,Maximum power point tracking,photovoltaic (PV)
更新于2025-09-19 17:13:59
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[IEEE 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - Chicago, IL, USA (2019.6.16-2019.6.21)] 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - Validation of Advanced Photovoltaic Module Materials and Processes by Combined-Accelerated Stress Testing (C-AST)
摘要： The current-fed dual active bridge (CF-DAB) dc–dc converter gains growing applications in photovoltaic (PV) and energy storage systems due to its advantages, e.g., a wide input voltage range, a high step-up ratio, a low input current ripple, and a multiport interface capability. In addition, the direct input current controllability and extra control freedom of the CF-DAB converter make it possible to buffer the double-line-frequency energy in grid-interactive PV systems without using electrolytic capacitors in the dc link. Therefore, a PV system achieves high reliability and highly ef?cient maximum power point tracking. This paper studies the optimized operation of a CF-DAB converter for a PV application in order to improve the system ef?ciency. The operating principle and soft-switching conditions over the wide operating range are thoroughly analyzed with phase-shift control and duty-cycle control, and an optimized operating mode is proposed to achieve the minimum root-mean-square transformer current. The proposed operating mode can extend the soft-switching region and reduce the power loss, particularly under a heavy load and a high input voltage. Moreover, the ef?ciency can be further improved with a higher dc-link voltage. A 5-kW hardware prototype was built in the laboratory, and experimental results are provided for veri?cation. This paper provides a design guideline for the CF-DAB converter applied to PV systems, as well as other applications with a wide input voltage variation.
关键词： soft switching,optimized operation,Current-fed dual active bridge (CF-DAB),photovoltaic (PV),root-mean-square (RMS) current
更新于2025-09-19 17:13:59
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[IEEE 2019 IEEE Conference on Power Electronics and Renewable Energy (CPERE) - Aswan City, Egypt (2019.10.23-2019.10.25)] 2019 IEEE Conference on Power Electronics and Renewable Energy (CPERE) - Virtual inertia impact on the performance of photovoltaic system
摘要： With the enormous stress of energy lack and air pollution, renewable energy sources such as photovoltaic sources become an effective solution to these problems. The penetration of photovoltaic sources into power system has adverse effects on overall moment of inertia and damping, this threatens system stability. To assist the stability, the concept of virtual synchronous generator (VSG) has introduced as an inverter control method to add virtual inertia to the system. This paper demonstrates the effects of adding virtual inertia on the system performance when fed from a photovoltaic source. The effects of changing the system and VSG parameters on the overall performance is also studied to show the appropriate change in each parameter that enhance the performance. The theoretical results that obtained using the MATLAB/SIMULINK are verified experimentally, using a DSP-based laboratory model that fed from a PV source.
关键词： Virtual synchronous generator (VSG),Distributed generator (DG),Photovoltaic (PV)
更新于2025-09-19 17:13:59